{"id":8796,"date":"2020-12-04T08:07:04","date_gmt":"2020-12-04T08:07:04","guid":{"rendered":"http:\/\/besafenet.dgmedialink.com\/glissement-de-terrain\/"},"modified":"2024-06-11T14:07:33","modified_gmt":"2024-06-11T13:07:33","slug":"landslides","status":"publish","type":"page","link":"https:\/\/besafenet.net\/fr\/hazards\/landslides\/","title":{"rendered":"Glissement de terrain"},"content":{"rendered":"\t\t<div data-elementor-type=\"wp-page\" data-elementor-id=\"8796\" class=\"elementor elementor-8796 elementor-1539\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-68769c7 heading-section elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"68769c7\" data-element_type=\"section\" data-settings=\"{&quot;background_background&quot;:&quot;classic&quot;}\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-50 elementor-top-column elementor-element elementor-element-7067f8d\" data-id=\"7067f8d\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-9338fa5 elementor-widget elementor-widget-heading\" data-id=\"9338fa5\" data-element_type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">Risques Naturels<\/h2>\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-7d5d5d8 elementor-widget elementor-widget-heading\" data-id=\"7d5d5d8\" data-element_type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t<h1 class=\"elementor-heading-title elementor-size-default\">Glissement de terrain<\/h1>\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-50 elementor-top-column elementor-element elementor-element-feceaa3\" data-id=\"feceaa3\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-dc91ee1 elementor-widget-divider--view-line elementor-widget elementor-widget-divider\" data-id=\"dc91ee1\" data-element_type=\"widget\" data-widget_type=\"divider.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<div class=\"elementor-divider\">\n\t\t\t<span class=\"elementor-divider-separator\">\n\t\t\t\t\t\t<\/span>\n\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-9156ce1 small-txt elementor-widget elementor-widget-text-editor\" data-id=\"9156ce1\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><em>Pr\u00e9par\u00e9 par le CERG, Centre Europ\u00e9en sur les Risques G\u00e9omorphologiques (Strasbourg, France)<\/em><\/p>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-4875820 elementor-widget-divider--view-line elementor-widget elementor-widget-divider\" data-id=\"4875820\" data-element_type=\"widget\" data-widget_type=\"divider.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<div class=\"elementor-divider\">\n\t\t\t<span class=\"elementor-divider-separator\">\n\t\t\t\t\t\t<\/span>\n\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-9235812 elementor-section-height-min-height elementor-section-boxed elementor-section-height-default elementor-section-items-middle\" data-id=\"9235812\" data-element_type=\"section\" data-settings=\"{&quot;background_background&quot;:&quot;classic&quot;}\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-1471fc0\" data-id=\"1471fc0\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-8003f6b elementor-widget elementor-widget-image\" data-id=\"8003f6b\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"320\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/landslides-1024x320.jpg\" class=\"attachment-large size-large wp-image-1544\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/landslides-1024x320.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/landslides-300x94.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/landslides-768x240.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/landslides-1536x480.jpg 1536w, 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fill=\"#fff\"><\/path><\/svg><\/span><\/a><a aria-label=\"Email\" class=\"heateor_sss_email\" href=\"https:\/\/besafenet.net\/fr\/wp-json\/wp\/v2\/pages\/8796\" onclick=\"event.preventDefault();window.open('mailto:?subject=' + decodeURIComponent('Glissement%20de%20terrain').replace('&', '%26') + '&body=https%3A%2F%2Fbesafenet.net%2Ffr%2Fwp-json%2Fwp%2Fv2%2Fpages%2F8796', '_blank')\" title=\"Email\" rel=\"nofollow noopener\" style=\"font-size:32px!important;box-shadow:none;display:inline-block;vertical-align:middle\"><span class=\"heateor_sss_svg\" style=\"background-color:#649a3f;width:35px;height:35px;display:inline-block;opacity:1;float:left;font-size:32px;box-shadow:none;display:inline-block;font-size:16px;padding:0 4px;vertical-align:middle;background-repeat:repeat;overflow:hidden;padding:0;cursor:pointer;box-sizing:content-box\"><svg style=\"display:block;\" focusable=\"false\" aria-hidden=\"true\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"100%\" height=\"100%\" viewBox=\"-.75 -.5 36 36\"><path d=\"M 5.5 11 h 23 v 1 l -11 6 l -11 -6 v -1 m 0 2 l 11 6 l 11 -6 v 11 h -22 v -11\" stroke-width=\"1\" fill=\"#fff\"><\/path><\/svg><\/span><\/a><\/div><div class=\"heateorSssClear\"><\/div><\/div><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-16cbf0a elementor-widget elementor-widget-text-editor\" data-id=\"16cbf0a\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Un glissement de terrain correspond g\u00e9n\u00e9ralement \u00e0 un d\u00e9placement gravitaire de terrains meubles ou rocheux le long d&rsquo;une surface de rupture.<\/p>\n<p>Il s\u2019agit d\u2019un processus g\u00e9ologique appartenant \u00e0 la cat\u00e9gorie des \u00ab\u00a0MOUVEMENTS DE TERRAIN\u00a0\u00bb, terme d\u00e9signant un mouvement ext\u00e9rieur ou descendant de terrains meubles le long d\u2019une pente par gravit\u00e9. Les glissements de terrain se distinguent des autres mouvements de terrain par la pr\u00e9sence de limites nettes et une vitesse de d\u00e9placement sensiblement sup\u00e9rieure \u00e0 celle des autres d\u00e9placements observ\u00e9s sur les pentes adjacentes.<\/p>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-13d66e2 elementor-widget elementor-widget-accordion\" data-id=\"13d66e2\" data-element_type=\"widget\" data-widget_type=\"accordion.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<div class=\"elementor-accordion\" role=\"tablist\">\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-2081\" class=\"elementor-tab-title\" data-tab=\"1\" role=\"tab\" aria-controls=\"elementor-tab-content-2081\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">1. Qu\u2019est-ce qu\u2019un glissement de terrain ?<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-2081\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"1\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-2081\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"7917\" class=\"elementor elementor-7917 elementor-1558\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-c959c45 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"c959c45\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-5e018ad\" data-id=\"5e018ad\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-82cbe03 elementor-widget elementor-widget-text-editor\" data-id=\"82cbe03\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Un glissement de terrain correspond \u00e0 un d\u00e9placement gravitaire de terrains meubles ou rocheux le long d&rsquo;une surface de rupture.<\/p>\n<p>C\u2019est un processus g\u00e9ologique appartenant \u00e0 la cat\u00e9gorie des \u00ab\u00a0MOUVEMENTS DE TERRAIN\u00a0\u00bb, terme d\u00e9signant un mouvement ext\u00e9rieur ou descendant de terrains meubles le long d\u2019une pente par gravit\u00e9.<\/p>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-cad832c elementor-widget elementor-widget-image\" data-id=\"cad832c\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"350\" height=\"334\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/landslide.gif\" class=\"attachment-large size-large wp-image-1563\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-ae61162 elementor-widget elementor-widget-text-editor\" data-id=\"ae61162\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Les glissements de terrain se distinguent des autres mouvements de terrain par la pr\u00e9sence de limites nettes et une vitesse de d\u00e9placement sensiblement sup\u00e9rieure \u00e0 celle des autres d\u00e9placements observ\u00e9s sur les pentes adjacentes.<\/p>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-15ac279 elementor-widget elementor-widget-image\" data-id=\"15ac279\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"547\" height=\"387\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Landsl2.jpg\" class=\"attachment-large size-large wp-image-1568\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Landsl2.jpg 547w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Landsl2-300x212.jpg 300w\" sizes=\"(max-width: 547px) 100vw, 547px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Image commonly used to illustrate the parts of a landslide (from Varnes, 1978)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-710c6ce elementor-widget elementor-widget-text-editor\" data-id=\"710c6ce\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>La partie sup\u00e9rieure est la zone d\u2019affaissement (ou frange d\u2019alt\u00e9ration ou encore front d\u2019\u00e9rosion), point de d\u00e9part d\u2019une masse de terrain d\u00e9stabilis\u00e9e vers le bas d\u2019une pente.<\/p>\n<p>La masse \u00ab\u00a0gliss\u00e9e\u00a0\u00bb peut rester proche de la zone d\u2019affaissement ou poursuivre son glissement le long d\u2019un axe de ravinement pour former un bourrelet d\u2019accumulation au pied de la pente, ou encore se joindre \u00e0 d\u2019autres agents g\u00e9omorphologiques (rivi\u00e8re, mer, glacier, etc.). La distance parcourue par la masse gliss\u00e9e (distance de glissement) est une caract\u00e9ristique des diff\u00e9rents types de glissements de terrain.<\/p>\n<p>Les d\u00e9p\u00f4ts des glissements de terrain varient en texture d\u2019un amas de roches disloqu\u00e9es \u00e0 partir d\u2019une source intacte \u00e0 des s\u00e9diments finement fragment\u00e9s formant une masse non stratifi\u00e9e de d\u00e9bris de tous types.<\/p>\n<p>Les glissements de terrain se classent en sept \u00e9tats d\u2019activit\u00e9, dont deux principaux :<\/p>\n<p><strong>Actif\u00a0<\/strong>: le glissement de terrain a \u00e9volu\u00e9 au cours des douze derniers mois.<br \/>\n<strong>Inactif\u00a0<\/strong>: le glissement de terrain n\u2019a pas \u00e9volu\u00e9 au cours des douze derniers mois.<\/p>\n<p>Plus pr\u00e9cis\u00e9ment, un glissement de terrain peut \u00eatre\u00a0:<\/p>\n<ul>\n<li><strong>actif\u00a0<\/strong>: actuellement en mouvement\u00a0;<\/li>\n<li><strong>en suspens\u00a0<\/strong>: en mouvement au cours des douze derniers mois mais inactif pour le moment\u00a0;<\/li>\n<li><strong>r\u00e9activ\u00e9\u00a0<\/strong>: glissement actif \u00e0 la suite d\u2019une p\u00e9riode d\u2019inactivit\u00e9\u00a0;<\/li>\n<li><strong>latent\u00a0<\/strong>: glissement inactif pouvant \u00eatre r\u00e9activ\u00e9 par ses \u00e9l\u00e9ments d\u00e9clencheurs ou par d\u2019autres causes\u00a0;<\/li>\n<li><strong>naturellement stabilis\u00e9\u00a0<\/strong>: glissement inactif n\u2019\u00e9tant plus soumis \u00e0 ses \u00e9l\u00e9ments d\u00e9clencheurs ;<\/li>\n<li><strong>artificiellement stabilis\u00e9\u00a0<\/strong>: glissement inactif isol\u00e9 de ses \u00e9l\u00e9ments d\u00e9clencheurs par des moyens correctifs\/palliatifs anthropiques\u00a0;<\/li>\n<li><strong>ancien\u00a0<\/strong>: glissement inactif d\u00e9velopp\u00e9 dans des conditions climatiques et g\u00e9omorphologiques sensiblement diff\u00e9rentes des conditions actuelles.<\/li>\n<\/ul>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-ddc114d elementor-widget elementor-widget-accordion\" data-id=\"ddc114d\" data-element_type=\"widget\" data-widget_type=\"accordion.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<div class=\"elementor-accordion\" role=\"tablist\">\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-2321\" class=\"elementor-tab-title\" data-tab=\"1\" role=\"tab\" aria-controls=\"elementor-tab-content-2321\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">1.1 More information on \u2018landslide form\u2019<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-2321\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"1\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-2321\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"1578\" class=\"elementor elementor-1578\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-c746853 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"c746853\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-f560c57\" data-id=\"f560c57\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-555dc72 elementor-widget elementor-widget-text-editor\" data-id=\"555dc72\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>There are several morphological features that can be recognized to a greater or lesser extent in most landslides. The uppermost part is the depletion or concave zone (erosional, generating or failure zone) where slope material has failed and become displaced downslope. In some cases the displacement may be only a few metres while in others the failure zone will be completely evacuated to expose the surface of rupture and to leave a distinctive scar on the hillslope.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-83048db elementor-widget elementor-widget-image\" data-id=\"83048db\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"547\" height=\"387\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Landsl2.jpg\" class=\"attachment-large size-large wp-image-1568\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Landsl2.jpg 547w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Landsl2-300x212.jpg 300w\" sizes=\"(max-width: 547px) 100vw, 547px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 1. Image commonly used to illustrate the part of a landslide (from Varnes, 1978)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-e1fb10d elementor-widget elementor-widget-image\" data-id=\"e1fb10d\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"786\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/RBSUnt_018-1024x786.jpg\" class=\"attachment-large size-large wp-image-1582\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/RBSUnt_018-1024x786.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/RBSUnt_018-300x230.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/RBSUnt_018-768x589.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/RBSUnt_018-1536x1179.jpg 1536w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/RBSUnt_018.jpg 1539w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 2. Translational rock slide, occured in Novembre 1994 in the Langhe Hills (Piemonte Region), in which can be clearly distiguished the main scarp, the flanks and the displaced material (photo from Archivio CNR-IRPI, Torino)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-0891e34 elementor-widget elementor-widget-text-editor\" data-id=\"0891e34\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>The displaced mass may remain close to the failure zone or it may continue to travel downslope leaving a transport track ending in a colluvial accumulation zone or acting as a supply to some other geomorphic agent (e.g. river, sea or glacier). The distance that landslide material travels (runout) is a characteristic of the type of land- slide. For example, controlled by the height of fall and volume, rock avalanches can travel at high velocity for several kilometres. Runout distance and velocity for other types of landslide are controlled by factors such as volume, slope angle and morphology, clay content, water content, and surface frictional characteristics of the runout pathway.<\/p><p>For the references herein and for knowing sources of didactic material go to 1.3 Selected references<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p>\n<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-2322\" class=\"elementor-tab-title\" data-tab=\"2\" role=\"tab\" aria-controls=\"elementor-tab-content-2322\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">1.2 More information on \u2018landslide activity\u2019<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-2322\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"2\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-2322\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"1589\" class=\"elementor elementor-1589\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-9d2cf01 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"9d2cf01\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-7d2d45e\" data-id=\"7d2d45e\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-bddc811 elementor-widget elementor-widget-text-editor\" data-id=\"bddc811\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Case of landslide mainly governed by climatic conditions:<\/p><p>1. Slope is stable: Water table is at its lowest level. The safety factor F is &gt; 1 (the resisting forces are superior to the driving forces).<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-bb94f13 elementor-widget elementor-widget-image\" data-id=\"bb94f13\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"675\" height=\"587\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Stades_Glissement_A.jpg\" class=\"attachment-large size-large wp-image-1594\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Stades_Glissement_A.jpg 675w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Stades_Glissement_A-300x261.jpg 300w\" sizes=\"(max-width: 675px) 100vw, 675px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-5cdc820 elementor-widget elementor-widget-text-editor\" data-id=\"5cdc820\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>2.\u00a0First failure phase: Due to the water table rises, the safety factor F is &lt; 1. The Archimedes thrust lifts or lightens the soil. Thus, a decrease in the friction forces along the slip surface promotes movement. Rate of displacement can be more or less important. According to the climatic conditions, water table level could decrease and the slope could be \u201ctemporarily\u201d stabilized (active or dormant!).<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-628facc elementor-widget elementor-widget-image\" data-id=\"628facc\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"675\" height=\"587\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Stades_Glissement_B.jpg\" class=\"attachment-large size-large wp-image-1599\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Stades_Glissement_B.jpg 675w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Stades_Glissement_B-300x261.jpg 300w\" sizes=\"(max-width: 675px) 100vw, 675px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-83f487d elementor-widget elementor-widget-text-editor\" data-id=\"83f487d\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>3. Second failure phase: In the event of rainy conditions, water table rises at a high level and major displacements occur. Main scarp is clearly observed. In the rear of the main scarp, on of the landslide crown, new cracks could appear.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-3e71dfc elementor-widget elementor-widget-image\" data-id=\"3e71dfc\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"675\" height=\"587\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Stades_Glissement_C.jpg\" class=\"attachment-large size-large wp-image-1604\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Stades_Glissement_C.jpg 675w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Stades_Glissement_C-300x261.jpg 300w\" sizes=\"(max-width: 675px) 100vw, 675px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-8457a51 elementor-widget elementor-widget-text-editor\" data-id=\"8457a51\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>4.Reactivation: If water table rises at its highest level, reactivation along extended slip surface occurs. Secondary scarp is now well observed. According to the predisposition factors (morphological features, geological factors, land cover), water table level (or triggering threshold) which provoke the instability is different for each slope.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-6df1cab elementor-widget elementor-widget-image\" data-id=\"6df1cab\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"675\" height=\"587\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Stades_Glissement_D.jpg\" class=\"attachment-large size-large wp-image-1609\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Stades_Glissement_D.jpg 675w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Stades_Glissement_D-300x261.jpg 300w\" sizes=\"(max-width: 675px) 100vw, 675px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 1: Example of the Villerville-Cricqueboeuf landslide (&gt;&gt;see case study Villerville-Cricqueboeuf landslide): four states of instability in relation with piezometric variations and effective annual rainfall. Major displacements correspond to a repetition of these four phases with time (from Maquaire and Malet, 2006)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-797ed83 elementor-widget elementor-widget-text-editor\" data-id=\"797ed83\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><strong>Note:<\/strong>\u00a0delay between each phase can be very short (several days or months) or very long (several years or centuries!) &#8211; Notion of landslide activity<\/p><p>Landslide activity and morphological indicators:<\/p><p><strong>Seven states of activity are recognized and can be classified in two categories:<\/strong><\/p><ul><li>Active: landslide has moved within the last twelve months,<\/li><li>Inactive: landslide has not moved within the last twelve months.<\/li><\/ul><p>In detail, landslides can be:<\/p><ul><li>Active: landslide is currently moving,<\/li><li>Suspended: landslide has moved within the last twelve months but is not active at present,<\/li><li>Reactivated: landslide is active but has been inactive.<\/li><li>Dormant: inactive landslide can be reactivated by its original causes or by other causes<\/li><li>Abandoned: inactive landslide is no longer affected by its original causes<\/li><li>Stabilised: inactive landslide has been protected from its original causes by remedial measures<\/li><li>Relict: inactive landslide which developed under climatic or geomorphological conditions considerably different from those at present. It can not be reactivated.<\/li><\/ul><p>Figure 2 shows the seven states of activity of a landslide and morphological characteristics associated (from Dikau et al., 1996):<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-392eac2 elementor-widget elementor-widget-image\" data-id=\"392eac2\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"267\" height=\"153\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/dikau1.jpg\" class=\"attachment-medium size-medium wp-image-1614\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">A. Active landslide: erosion at the toe of the slope causes the topple of a block<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-a3974a9 elementor-widget elementor-widget-image\" data-id=\"a3974a9\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"264\" height=\"153\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/dikau2.jpg\" class=\"attachment-medium size-medium wp-image-1619\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">B. Suspended landslide: local cracking (red colour) in the crown of the topple<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-5be607b elementor-widget elementor-widget-image\" data-id=\"5be607b\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"270\" height=\"153\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/dikau3a.jpg\" class=\"attachment-medium size-medium wp-image-1624\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">C. Reactivated landslide: another block topples, disturbing the previously displaced material<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-36bfa3e elementor-widget elementor-widget-image\" data-id=\"36bfa3e\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"258\" height=\"163\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/dikau4.jpg\" class=\"attachment-medium size-medium wp-image-1629\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">D. Dormant landslide: the displaced mass begins to regain its tree cover, scarps are modified by weathering<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-905782c elementor-widget elementor-widget-image\" data-id=\"905782c\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"271\" height=\"163\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/dikau5.jpg\" class=\"attachment-medium size-medium wp-image-1634\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">E. Abandoned landslide: fluvial deposition has protected the toe of the slope &#8211; F. Stabilised landslide: a wall protects the toe of the slope<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-7020252 elementor-widget elementor-widget-image\" data-id=\"7020252\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"289\" height=\"163\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/dikau8.jpg\" class=\"attachment-medium size-medium wp-image-1639\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">G. Relict landslide: uniform tree cover has been established.<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-c4d1341 elementor-widget elementor-widget-text-editor\" data-id=\"c4d1341\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>These stages can be successive in time. Figure 3 shows the block diagrams of morphological changes with time of a rotational slide, from active state to dormant state, in arid or semiarid climate (from Keaton and Degraaf, 1996). Morphological features are great indicators to assess the state of activity of a landslide:<\/p><p><strong>1. Active or recently active landslide:\u00a0<\/strong>features are sharply defined and distinct. Bedrock is freshly exposed in the main scarp or the flanks. Water is ponded in closed depressions caused by rotational movement or by blockage of original runoff paths.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-1cb7b0c elementor-widget elementor-widget-image\" data-id=\"1cb7b0c\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"713\" height=\"449\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/keaton_couleur.jpg\" class=\"attachment-large size-large wp-image-1646\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/keaton_couleur.jpg 713w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/keaton_couleur-300x189.jpg 300w\" sizes=\"(max-width: 713px) 100vw, 713px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-d532e09 elementor-widget elementor-widget-text-editor\" data-id=\"d532e09\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><strong>2. Dormant-young landslide:<\/strong>\u00a0features remain clear but are not sharply defined owing to slope wash and shallow mass movements on steep scarps. Although bedrock is still visible in many places, weathering has obscured the original structure. Drainage lines are not established.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-df98c03 elementor-widget elementor-widget-image\" data-id=\"df98c03\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"652\" height=\"459\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/keaton_couleur2.jpg\" class=\"attachment-large size-large wp-image-1651\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/keaton_couleur2.jpg 652w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/keaton_couleur2-300x211.jpg 300w\" sizes=\"(max-width: 652px) 100vw, 652px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-57eab05 elementor-widget elementor-widget-text-editor\" data-id=\"57eab05\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><strong>3. Dormant-mature landslide:<\/strong>\u00a0Drainage follows rifts and sags on slide mass, internal blocks are slightly dissected and material is eroded from slide mass.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-3c364f2 elementor-widget elementor-widget-image\" data-id=\"3c364f2\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"874\" height=\"574\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/keaton_couleur3.jpg\" class=\"attachment-large size-large wp-image-1662\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/keaton_couleur3.jpg 874w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/keaton_couleur3-300x197.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/keaton_couleur3-768x504.jpg 768w\" sizes=\"(max-width: 874px) 100vw, 874px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-a53cd1b elementor-widget elementor-widget-text-editor\" data-id=\"a53cd1b\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><strong>4. Dormant-old landslide:<\/strong>\u00a0features are weak and often subtle. Slide mass is almost completely removed, drainage network shows weak structural control, valley drainage re-establishes its pre-slide profile.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-c05d134 elementor-widget elementor-widget-image\" data-id=\"c05d134\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"869\" height=\"570\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/keaton_couleur4.jpg\" class=\"attachment-large size-large wp-image-1657\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/keaton_couleur4.jpg 869w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/keaton_couleur4-300x197.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/keaton_couleur4-768x504.jpg 768w\" sizes=\"(max-width: 869px) 100vw, 869px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-59d31ce elementor-widget elementor-widget-text-editor\" data-id=\"59d31ce\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Figure 4 shows the block diagrams of morphological changes with time of a rotational slide, from active state to dormant state, in humid climate (from Keaton and Degraaf, 1996):<\/p><p><strong>A. Active or recently active landslide:<\/strong>\u00a0features are sharply defined and distinct. Bedrock is freshly exposed in the main scarp or the flanks. Many cracks exist above and subparallel to the main scarp; cracks extend across the slide; radial cracks occur within the toe portion. Original vegetation has been disrupted. The present orientation of vegetation indicates direction of principal movement and rotation (figure 5). Water is ponded in closed depressions caused by rotational movement or by blockage of original runoff paths.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-ca94fd1 elementor-widget elementor-widget-image\" data-id=\"ca94fd1\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"567\" height=\"375\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/keaton.jpg\" class=\"attachment-large size-large wp-image-1668\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/keaton.jpg 567w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/keaton-300x198.jpg 300w\" sizes=\"(max-width: 567px) 100vw, 567px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-a20d8f4 elementor-widget elementor-widget-text-editor\" data-id=\"a20d8f4\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><strong>B. Dormant-young landslide:<\/strong>\u00a0features remain clear but are not sharply defined owing to slope wash and shallow mass movements on steep scarps. Although bedrock is still visible in many places, weathering has obscured the original structure. Cracks are no longer visible within or adjacent to the slide mass. Hydrophilic vegetation has established itself in the ponded areas. Minor scarps and transverse ridges have been modified and the ground has a distinctive hummocky appearance.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-37c7dab elementor-widget elementor-widget-image\" data-id=\"37c7dab\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"623\" height=\"485\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/keaton2.jpg\" class=\"attachment-large size-large wp-image-1673\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/keaton2.jpg 623w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/keaton2-300x234.jpg 300w\" sizes=\"(max-width: 623px) 100vw, 623px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-7134951 elementor-widget elementor-widget-text-editor\" data-id=\"7134951\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><strong>C. Dormant-mature landslide:\u00a0<\/strong>features are modified by surface drainage, internal erosion and vegetation. Erosion has reduced the slopes of the scarp, flank and toe regions. Erosion has resulted in gullies and establishment of new drainage paths within and adjacent to the landslide. Likewise the original hummocky surface has been somewhat subdued.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-90e2757 elementor-widget elementor-widget-image\" data-id=\"90e2757\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"575\" height=\"415\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/keaton3.jpg\" class=\"attachment-large size-large wp-image-1679\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/keaton3.jpg 575w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/keaton3-300x217.jpg 300w\" sizes=\"(max-width: 575px) 100vw, 575px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-a731b67 elementor-widget elementor-widget-text-editor\" data-id=\"a731b67\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><strong>D. dormant-old landslide:<\/strong>\u00a0features are weak and often subtle. Slope breaks are indistinguishable from scarp, flank and toe regions. Neither vegetation nor developed runoff paths reflect original landslide boundaries. The disturbed area has been completely filled with silt and heavy vegetation has disguised its location.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-90104af elementor-widget elementor-widget-image\" data-id=\"90104af\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"619\" height=\"438\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/keaton4.jpg\" class=\"attachment-large size-large wp-image-1684\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/keaton4.jpg 619w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/keaton4-300x212.jpg 300w\" sizes=\"(max-width: 619px) 100vw, 619px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-540ded2 elementor-widget elementor-widget-text-editor\" data-id=\"540ded2\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><strong>Use of vegetation:<\/strong><\/p><p>Vegetation is also used as indicator of landslide activity. It can permit to assess the degree of activity, age, type and component parts of a landslide. The term \u201cdendrogeomorphology\u201d (in Greek \u201cdendro\u201d means \u201ctree\u201d) is used to define the study of geomorphic processes using data gathered from trees. Tree growing on an instable slope is liable to develop a tilting or a curvature in the direction of the movement. Analysis of external deformations of the tree gives information on landslide activity.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-0ad76e0 elementor-widget elementor-widget-image\" data-id=\"0ad76e0\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"625\" height=\"398\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/curvedtree_brunsden.jpg\" class=\"attachment-large size-large wp-image-1689\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/curvedtree_brunsden.jpg 625w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/curvedtree_brunsden-300x191.jpg 300w\" sizes=\"(max-width: 625px) 100vw, 625px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 5: Characteristically deformed tree on partially stabilized landslide (from Brunsden and Prior, 1984)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-45d0159 elementor-widget elementor-widget-text-editor\" data-id=\"45d0159\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Trees that have been tilted from the vertical also undergo changes to internal tissue as they respond to the altered growing conditions. Coniferous trees support new growth by adding \u201ccompression tissue\u201d on the lower side of the trunk, whereas deciduous trees develop \u201ctension tissue\u201d mainly on the upper side. Investigation of tissue disturbance in combination with analysis of the eccentricity of the tree annual rings can be used to determine dates of significant movement of the slope.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-173186c elementor-widget elementor-widget-image\" data-id=\"173186c\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"430\" height=\"336\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/braam.jpg\" class=\"attachment-large size-large wp-image-1696\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/braam.jpg 430w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/braam-300x234.jpg 300w\" sizes=\"(max-width: 430px) 100vw, 430px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 6: Mass movement induced movement of a coniferous tree, curvature of the trunk and consequent eccentric growth of annual rings (from Braam and al., 1987)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-a35bda4 elementor-widget elementor-widget-text-editor\" data-id=\"a35bda4\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Dendrogeomorphology is used to assess slide activity, debris flow activity and also rock fall activity.<\/p><p>For the references herein and for knowing sources of didactic material go to 1.3 Selected references\u00a0<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p>\n<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-2323\" class=\"elementor-tab-title\" data-tab=\"3\" role=\"tab\" aria-controls=\"elementor-tab-content-2323\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">1.3 Selected references<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-2323\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"3\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-2323\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"1702\" class=\"elementor elementor-1702\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-18805d5 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"18805d5\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-8761e5e\" data-id=\"8761e5e\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-9164709 elementor-widget elementor-widget-text-editor\" data-id=\"9164709\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>BRAAM R.R., WEISS E.E.J., BURROUGH P.A., 1987. Spatial and temporal analysis of mass movement using dendrochronology. Catena, vol. 14, 1987b. p. 573-584<br \/><br \/>BRUNSDEN D., PRIOR D., 1984. Slope instability. John Wiley &amp; Sons Ltd, Chichester<br \/><br \/>CROZIER M.J., 2004. Landslide in GOUDIE A.S. (Ed.), 2004. Encyclopedia of Geomorphology. Vol. 2, 605-608. Routledge, London and New York<br \/><br \/>CRUDEN, D.M. &amp; VARNES, D.J., 1996. Landslides Types and Processes. In: A.K. TURNER &amp; R.L. SCHUSTER (Editors), Landslides: Investigation and Mitigation. Transportation Research Board, National Academy of Sciences, Washington D.C., Special Report 247, pp. 36-75.<br \/><br \/>DIKAU R., BRUNSDEN D., SCHROTT L., IBSEN M.-L. (eds.), 1996. Landslide Recognition: Identification, Movement and Causes. John Wiley &amp; Sons Ltd, Chichester.<br \/><br \/>FLAGEOLLET, J.-C., MALET, J.-P., MAQUAIRE, O., SCHMUTZ, M., 2004. Integrated investigations on landslides: example of the Super-Sauze earthflow. In Margottini, C. (Ed): Natural Disasters and Sustainable Development, Springer-Verlag, Berlin, Chapter 14, 213-238.<br \/><br \/>GLADE, T., ANDERSON , M., CROZIER M., J. (ed.s), 2009. Landslide hazard and natural risks. John Wiley &amp; Sons Ltd, Chichester.<br \/><br \/>HIGHLAND L. M., BOBWROSKY P., 2008. The Landslide Handbook &#8211; A Guide to Understanding Landslides. Downloadable at USGS website. http:\/\/pubs.usgs.gov\/circ\/1325\/<br \/><br \/>IAEG (Commission on Landslides), 1990. Suggested nomenclature for Landslides. IAEG Bull., 41: 13-16.<br \/><br \/>KEATON, J.R., DEGRAAF, J.V., 1996. Surface Observation and Geologic Mapping. In: TURNER, SCHUSTER (EDS) \u201cLandslides : investigation and mitigation\u201d. Transportation Research Board &#8211; National Research Council, Special Report 247, Washington, D.C., National Academy Press, pp. 178-230.<br \/><br \/>MALET, J.-P., MAQUAIRE, O.. 2004. Hydrological behaviour of earthflows developed in clay-shales: investigation, concept and modelling. In Picarelli, L. (Ed): The Occurrence and Mechanisms of Flows in Natural Slopes and Earthfills, Patron Editore, Bologna, 175-193.<br \/><br \/>MAQUAIRE, O., 2005. Geomorphic hazards and natural risks, In: Koster, E., A. (ed.), The Physical Geography of Western Europe, Oxford Regional Environments, Oxford University Press, Chapter 18, 354-377.<br \/><br \/>MAQUAIRE, O., MALET J.-P., 2006. Shallow landslidings. In BOARDMAN, J. A, POESEN, J. (Eds): Soil Erosion in Europe, Wiley, Chapter 2.8, 583-598.<br \/><br \/>PASUTO\u00a0A.&amp; SCHROTT L. &#8211; 1997.\u00a0 Eurolandslide. A visual journey through european mass movements. CNR &#8211; IRPI , Padova Italy. CD-ROM\u00a0Windows-Macintosh<br \/><br \/>SASSA K. (ed.), 1999. Landslides of the World. Kyoto University Press, Kyoto,<br \/><br \/>TURNER A.K. &amp; SCHUSTER R.L. (eds.),1996. Landslides: Investigation and Mitigation. Transportation Research Board, Special Report 247, National Academy Press, Washington D.C..<br \/><br \/>VALLARIO A., 1992. Frane e territorio. Liguori Editore, Napoli.<br \/><br \/>VARNES, D.J., 1978. Slope movements: types and processes. In: R.L. SCHUSTER &amp; R.J. KRIZEK (Editors), Landslides: Analysis and Control. Transportation Research Board, National Academy of Sciences, Washington D.C., Special Report, 176, pp. 11-33.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p>\n<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-2082\" class=\"elementor-tab-title\" data-tab=\"2\" role=\"tab\" aria-controls=\"elementor-tab-content-2082\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">2. What types of landslides are there?<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-2082\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"2\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-2082\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"7921\" class=\"elementor elementor-7921 elementor-1706\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-6e7f88f elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"6e7f88f\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-d5cd1f3\" data-id=\"d5cd1f3\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-6e68e57 elementor-widget elementor-widget-text-editor\" data-id=\"6e68e57\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Les formes et les dynamiques des glissements de terrain, tr\u00e8s diverses, r\u00e9pondent \u00e0 une classification pr\u00e9cise.<\/p>\n<p>Les principaux crit\u00e8res utilis\u00e9s pour classer les glissements de terrain sont les suivants\u00a0:<\/p>\n<ul>\n<li>type de mouvement (\u00e9boulement, basculement, glissement, extension lat\u00e9rale et \u00e9coulement par exemple),<\/li>\n<li>nature des mat\u00e9riaux gliss\u00e9s (roches, d\u00e9bris, terre par exemple),<\/li>\n<li>forme de la surface de rupture (incurv\u00e9e ou plane par exemple),<\/li>\n<li>intensit\u00e9 du mouvement de terrain,<\/li>\n<li>cin\u00e9matique du mouvement de terrain.\n<p>Ce dernier crit\u00e8re rev\u00eat une importance pratique non n\u00e9gligeable dans le sens o\u00f9 il traduit indirectement les probabilit\u00e9s que les populations expos\u00e9es au mouvement de terrain aient le temps ou non d\u2019y \u00e9chapper.<br \/>\nLa cin\u00e9matique varie \u00e9norm\u00e9ment d\u2019un mouvement de terrain \u00e0 un autre. Elle peut\u00a0:<\/li>\n<\/ul>\n<ul>\n<li>se limiter \u00e0 quelques centim\u00e8tres par an pendant des d\u00e9cennies pour certains glissements de terrain, ou<\/li>\n<li>atteindre 100 km\/h pour certains glissements de d\u00e9bris, voire 350 km\/h pour les avalanches rocheuses.<\/li>\n<\/ul>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-e2a872c elementor-widget elementor-widget-image\" data-id=\"e2a872c\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"483\" height=\"374\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/landslide2_1.jpg\" class=\"attachment-large size-large wp-image-1711\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/landslide2_1.jpg 483w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/landslide2_1-300x232.jpg 300w\" sizes=\"(max-width: 483px) 100vw, 483px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-5d98e9a elementor-widget elementor-widget-text-editor\" data-id=\"5d98e9a\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Une m\u00e9thode simple pour classifier les glissements de terrain consiste \u00e0 combiner le type de mouvement et le type de mat\u00e9riaux gliss\u00e9s. Cette m\u00e9thode de classification \u00e9l\u00e9mentaire a \u00e9t\u00e9 propos\u00e9e par Cruden et Varnes (1996). Sa premi\u00e8re version (Varnes, 1978) est pr\u00e9sent\u00e9e dans le tableau ci-dessous. L\u2019image qui suit repr\u00e9sente la classification des mouvements de terrain en blocs-diagrammes propos\u00e9e par Cruden et Varnes.<\/p>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-1e2b6cb elementor-widget elementor-widget-image\" data-id=\"1e2b6cb\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"931\" height=\"301\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Varnes1978.jpg\" class=\"attachment-large size-large wp-image-1717\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Varnes1978.jpg 931w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Varnes1978-300x97.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Varnes1978-768x248.jpg 768w\" sizes=\"(max-width: 931px) 100vw, 931px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-f14f263 elementor-widget elementor-widget-image\" data-id=\"f14f263\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"700\" height=\"931\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/landslip_types_www_bgs_ac_uk.jpg\" class=\"attachment-large size-large wp-image-1722\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/landslip_types_www_bgs_ac_uk.jpg 700w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/landslip_types_www_bgs_ac_uk-226x300.jpg 226w\" sizes=\"(max-width: 700px) 100vw, 700px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-f52bb07 elementor-widget elementor-widget-text-editor\" data-id=\"f52bb07\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>The block scheme of the Cruden &amp; Varnes&rsquo; landslide classification. Source:\u00a0British Geological Survey &#8211;\u00a0www.bgs.ac.uk Go to 2.1 More information on different types of landslide)<\/p>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-4939a18 elementor-widget elementor-widget-accordion\" data-id=\"4939a18\" data-element_type=\"widget\" data-widget_type=\"accordion.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<div class=\"elementor-accordion\" role=\"tablist\">\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-7671\" class=\"elementor-tab-title\" data-tab=\"1\" role=\"tab\" aria-controls=\"elementor-tab-content-7671\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">2.1 More information on different types of landslide<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-7671\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"1\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-7671\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"1730\" class=\"elementor elementor-1730\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-f2b2e58 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"f2b2e58\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-f2d2a25\" data-id=\"f2d2a25\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-71797ee elementor-widget elementor-widget-text-editor\" data-id=\"71797ee\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Criteria generally used to distinguish different types of landslide include: the movement mechanism (e.g. fall, topple, slide, spread and flow), the nature of the slope material involved (rock, debris, earth), the form (curved or planar) of the surface of rupture, the degree of disruption of the displaced mass, the rate of movement. To distinguish different types of landslide we privilege here the rate of movement as it indirectly expresses the opportunity given to people to escape at the onset of the phenomenon.<\/p><p>Rates of movement for different types of landslide are highly variable:<\/p><ul><li>Some landslides record only a few centimetres of movement a year, sustaining this rate for decades.<\/li><li>Certain debris flows have recorded velocities of 100 km\/h while large rock avalanches are capable of reaching velocities of 350 km\/h.<\/li><\/ul>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-3d11dd5 elementor-widget elementor-widget-image\" data-id=\"3d11dd5\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"640\" height=\"276\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Picture2.jpg\" class=\"attachment-large size-large wp-image-1733\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Picture2.jpg 640w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Picture2-300x129.jpg 300w\" sizes=\"(max-width: 640px) 100vw, 640px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-2c9a4ee elementor-widget elementor-widget-text-editor\" data-id=\"2c9a4ee\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><strong>To keep things simple, we distinguish two main classes:<\/strong><\/p><p><strong>Slow movements\u00a0<\/strong>The deformation is progressive and may be accompanied by rupture, but in principle with no sudden acceleration: it accelerates progressively and ends up in a sudden rupture after a phase of warning signs (cracks, deformations, subsidence), being not a direct threat if adequately monitored and controlled.<br \/>Go to 2.1.1 More details on slow movements.<\/p><p><strong>Rapid movements<\/strong><\/p><p>Movements may accelerate suddenly and they can be subdivided into two groups, depending on whether the material is propagated as a mass or reworked. These movements are more difficult to monitor and control and are consequently a major threat to personal safety.<br \/>Go to 2.1.2 More details on rapid movements<\/p><p>To be complete, at these two classes, we could add a third class which corresponding a spread. These are movements characterised by lateral spreading, typical of a jointed rock mass and often combined with subsidence occurring in softer, less competent underlying materials; sometimes it is not possible to recognise a basal slip surface nor well defined ductile deformation zones. Generally, the rock lateral spreading is a very slow movement but it can be very fast in the soil (debris) material: soil (debris)lateral spreading;<br \/>Go to 2.1.3 More details on lateral spreading<\/p><p>Another criterion used by the researchers in the identification of the landslide categories is the type of movement, whereas a further subdivision is made on the basis of the type of material.<br \/>Go to 2.1.4More information on classification<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-5d9bbc9 elementor-widget elementor-widget-accordion\" data-id=\"5d9bbc9\" data-element_type=\"widget\" data-widget_type=\"accordion.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<div class=\"elementor-accordion\" role=\"tablist\">\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-9811\" class=\"elementor-tab-title\" data-tab=\"1\" role=\"tab\" aria-controls=\"elementor-tab-content-9811\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">2.1.1 More details on slow movements<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-9811\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"1\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-9811\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"1741\" class=\"elementor elementor-1741\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-bdb1941 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"bdb1941\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-0e38772\" data-id=\"0e38772\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-53157d2 elementor-widget elementor-widget-text-editor\" data-id=\"53157d2\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Slow movements may be distinguished by the following:<\/p><p><strong>Sinking<\/strong><\/p><p>Sinking is the process of soil consolidation under load. It affects compressible soils (peats, clays, etc). Sinking is a differential process and can cause damage to structures and buildings. Sinking is like a limited progressive subsidence.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-bb8e253 elementor-widget elementor-widget-image\" data-id=\"bb8e253\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"185\" height=\"128\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Sinking_scheme_eng.jpg\" class=\"attachment-medium size-medium wp-image-1745\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-733518c elementor-widget elementor-widget-text-editor\" data-id=\"733518c\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><strong>Shrinking and swelling<\/strong><\/p><p>Shrinking is a process caused by the desiccation of the soils due to intense and\/or long periods of dryness. Shrinking produces slow, low amplitude, vertical deformations of the ground surface. Shrinking can be followed by progressive swelling processes when soil humidity is increased in the wet seasons. Clayey soils are particularly sensitive to shrinking and swelling because of the specific properties of clay minerals. Shrinking can damage buildings by partial and irregular sinking of the ground.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-f644b51 elementor-widget elementor-widget-image\" data-id=\"f644b51\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"217\" height=\"126\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Shrinking_Swelling_scheme_eng.jpg\" class=\"attachment-medium size-medium wp-image-1750\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-4e6c2ab elementor-widget elementor-widget-text-editor\" data-id=\"4e6c2ab\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><strong>Progressive subsidence<\/strong><\/p><p>Progressive subsidence is the process of slow surface deformation with or without fractures due to the evolution of natural or artificial caves (subterranean quarry or mines -iron, salt, coal, etc.-), circular or oval cavities or depressions appeared in surface. Go to 2.1.1.1 More information on progressive subsidence<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-9c85e2e elementor-widget elementor-widget-image\" data-id=\"9c85e2e\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"300\" height=\"132\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Progressive_subsidence_scheme_eng-300x132.jpg\" class=\"attachment-medium size-medium wp-image-1756\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Progressive_subsidence_scheme_eng-300x132.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Progressive_subsidence_scheme_eng.jpg 399w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-0d01d1b elementor-widget elementor-widget-text-editor\" data-id=\"0d01d1b\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><strong>Slide and Mudslide (or slump-earthflow):<\/strong><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-d463cf2 elementor-widget elementor-widget-image\" data-id=\"d463cf2\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"271\" height=\"152\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Rotational_slide.gif\" class=\"attachment-medium size-medium wp-image-1766\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-d8b5328 elementor-widget elementor-widget-image\" data-id=\"d8b5328\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"335\" height=\"157\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Translationnal_slide.gif\" class=\"attachment-large size-large wp-image-1761\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-2ed370f elementor-widget elementor-widget-text-editor\" data-id=\"2ed370f\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>The movement takes place by means of a shear displacement along one or more surfaces or along thin zones of intense shear strain. Either rotational slides (slumps), in which the movement occurs along a curved and concave failure surface, or translational slides, in which the mass moves along a plane or undulating surface, can be found. Go to 2.1.1.2 More information on slide<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-63f9d67 elementor-widget elementor-widget-image\" data-id=\"63f9d67\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"323\" height=\"188\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Mudslide.jpg\" class=\"attachment-large size-large wp-image-1772\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Mudslide.jpg 323w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Mudslide-300x175.jpg 300w\" sizes=\"(max-width: 323px) 100vw, 323px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-c03b634 elementor-widget elementor-widget-text-editor\" data-id=\"c03b634\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>In some cases, a slide can change into a mudslide or slump-earthflow, especially on steep slopes, in highly tectonized clays or silty formations (Picarelli, 2001; Maquaire et al., 2003). As shown in figure 13, three morphological units can be distinguished: a primary source area with the main scarp and cracks, a track zone thinly covered by a flow (the paleotopography is still clearly discernible), and an accumulation zone, sometimes with several successive lobes. Go to 2.1.1.2 More information on slide&gt;&gt; &lt;&lt; Return to More information on different types of landslide<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-ebef521 elementor-widget elementor-widget-accordion\" data-id=\"ebef521\" data-element_type=\"widget\" data-widget_type=\"accordion.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<div class=\"elementor-accordion\" role=\"tablist\">\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-2471\" class=\"elementor-tab-title\" data-tab=\"1\" role=\"tab\" aria-controls=\"elementor-tab-content-2471\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">2.1.1.1 More information on progressive subsidence<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-2471\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"1\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-2471\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"1780\" class=\"elementor elementor-1780\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-c758daa elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"c758daa\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-0638cb2\" data-id=\"0638cb2\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-86df9a8 elementor-widget elementor-widget-image\" data-id=\"86df9a8\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"530\" height=\"224\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/landslides2_1_1_11.jpg\" class=\"attachment-large size-large wp-image-1793\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/landslides2_1_1_11.jpg 530w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/landslides2_1_1_11-300x127.jpg 300w\" sizes=\"(max-width: 530px) 100vw, 530px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Progressive subsidence scheme (from Maquaire, 2005)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-6e2a6a4 elementor-widget elementor-widget-text-editor\" data-id=\"6e2a6a4\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Progressive subsidence is the process of slow surface deformation with or without fractures due to the evolution of natural or artificial caves (subterranean quarry or mines -iron, salt, coal, etc.-), circular or oval cavities or depressions appeared in surface,<\/p><p><strong>What is a progressive subsidence phenomenon?<\/strong><\/p><p>Subsidence, like sinking, is a very slow process of vertical deformation of large extent. The deformations are triggered by:<\/p><ul><li>The natural dissolution of soluble materials (karst phenomena),<\/li><li>The extraction of materials (calcareous, etc.) or extraction of ores (iron, salt, coal, etc.).<\/li><\/ul><p>Subsidence is a phenomenon relatively slow which can last of many years. It generally occurs in ground terrains with flexible behaviour, or in the case of artificial cavities (subterranean quarry or mines), when the depth of exploitation is important compared to the thickness of the size. Subsidence can be the precursor sign of an evolution by rapid subsidence. Subsidence (with vertical component of the movement) results in low depth of vast topographic depressions, generating relative deformations prejudicial to the structures, or, on a large scale, a disorganization of the system of drainage. In limit of these depressions (called sink hole in case of a karst dissolution), zones in extension (with shearing and traction, yielding stresses) can lead to the appearance of cracks.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-b186eea elementor-widget elementor-widget-image\" data-id=\"b186eea\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"478\" height=\"233\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/landslides2_1_1_12.jpg\" class=\"attachment-large size-large wp-image-1788\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/landslides2_1_1_12.jpg 478w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/landslides2_1_1_12-300x146.jpg 300w\" sizes=\"(max-width: 478px) 100vw, 478px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-a0885ea elementor-widget elementor-widget-text-editor\" data-id=\"a0885ea\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Scheme of the progressive subsidence process above a subterranean quarry by slow and progressive deformation of the ground terrain with flexible behaviour. With these indications: below, the extension of the subsidence zone, and. above, the extension of the influenced zone (from BRGM, website BDcavit\u00e9.net, developed by BRGM).<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-69c9a64 elementor-widget elementor-widget-image\" data-id=\"69c9a64\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"323\" height=\"215\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/landslides2_1_1_13.jpg\" class=\"attachment-large size-large wp-image-1783\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/landslides2_1_1_13.jpg 323w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/landslides2_1_1_13-300x200.jpg 300w\" sizes=\"(max-width: 323px) 100vw, 323px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Karstic doline in Vercors due to the dissolution of limestones (Photo: O Maquaire, Cerg)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-4cda3d9 elementor-widget elementor-widget-text-editor\" data-id=\"4cda3d9\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><strong>References:<\/strong><br \/>COTE, PH., FAUCHARD, C., POTHERAT, P. (2005). M\u00e9thodes g\u00e9ophysiques pour la localisation de cavit\u00e9s souterraines : potentialit\u00e9s et limites. In Evaluation et gestion es risques li\u00e9s aux carri\u00e8res souterraines abandonn\u00e9es. Actes des journ\u00e9es scientifiques du LCPC, pp. 8-17.<\/p><p>EMBLETON, C., AND EMBLETON C. (EDS.) (1997), Geomorphological Hazards of Europe. Developments in Earth Surface Processes 5. Amsterdam : Elsevier, 524p.<\/p><p>FLAGEOLLET, J. C. (1988), Les mouvements de terrain et leur pr\u00e9vention, Paris : Masson, 224p. LCPC (2000). Guide technique pour la caract\u00e9risation et cartographie de l\u2019al\u00e9a d\u00fb aux mouvements de terrain. Collection \u2018les risques naturels\u2019. Laboratoire Central des Ponts et Chauss\u00e9es, 91 p.<\/p><p>MAQUAIRE, O., (2005). Geomorphic hazards and natural risks, In: Koster, E., A. (ed.), The Physical Geography of Western Europe, Oxford Regional Environments, Oxford University Press, Chapter 18, 354-377.<\/p><p>MINISTERE DE L\u2019ENVIRONNEMENT, (1997), Plans de pr\u00e9vention des risques naturels (PPR) : guide g\u00e9n\u00e9ral.. La Documentation Fran\u00e7aise, Paris, 76p.<\/p><p>MINISTERE DE L\u2019ENVIRONNEMENT, (1999), Plans de pr\u00e9vention des risques naturels (PPR) : risques de mouvements de terrain. Guide m\u00e9thodologique.. La Documentation Fran\u00e7aise, Paris, 71p.<\/p><p>MINISTERE DE L\u2019ECOLOGIE ET DU DEVELOPPEMENT DURABLE, (2004). Dossier d\u2019information sur le risque Mouvement de terrains, 20 p. (\u00e0 t\u00e9l\u00e9charger sur site du MEDD).<\/p><p>POTHERAT, P. (2005). L\u2019op\u00e9ration de recherche \u00ab Carri\u00e8res souterraines abandonn\u00e9es \u00bb. Localisation, diagnostic de stabilit\u00e9, gestion. Rapport de synth\u00e8se. G\u00e9otechnique et risques naturels, GT 77. LCPC, 132 p.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-2472\" class=\"elementor-tab-title\" data-tab=\"2\" role=\"tab\" aria-controls=\"elementor-tab-content-2472\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">2.1.1.2 More info on slide phenomenon<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-2472\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"2\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-2472\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"1800\" class=\"elementor elementor-1800\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-b34267a elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"b34267a\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-5d0f995\" data-id=\"5d0f995\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-025cf80 elementor-widget elementor-widget-text-editor\" data-id=\"025cf80\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Extract from Maquaire and Malet, 2006)<\/p><p>A slide is a mass movement of material throughout the length of a \u2018rupture\u2019 or \u2018sliding\u2019 surface. Slide could be rotational (the sliding surface is curved) or translational (the sliding surface is more or less straight). It depends on the materials but also on the shape and length of the slope. The 1:10 ratio between depth and length is a criterion for the classification of a landslide rotational or translational. Many slides are composite and the movement takes place over the length of a sliding surface which is concave upstream and flat downstream. Many slides also occur over an irregular surface (Flageollet, 1988), and they vary considerably because of the nature and size of the materials (fragments of coherent rock, loose rock, soil) and the velocity.<\/p><p><strong>Rotational slides<\/strong><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-4ffac54 elementor-widget elementor-widget-image\" data-id=\"4ffac54\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"708\" height=\"407\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig1.gif\" class=\"attachment-large size-large wp-image-1803\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-3ed2e26 elementor-widget elementor-widget-text-editor\" data-id=\"3ed2e26\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>A single rotational slide is a \u2018more or less rotational movement, about an axis that is parallel to the slope contours, involving shear displacement (sliding) along a concavely upward-curving failure surface, which is visible or may reasonably be inferred\u2019 (Varnes, 1978). The morphology of the rotational slide is typical (Figure): upstream a main scarp with a steep slope, which is the visible part of the sliding surface, and tilted blocks (counterslopes) curtailed by scars along which slide striations are sometimes visible.<\/p><p>Figure 1: Typical block diagram of a rotational slide (from Dikau et al., 1996)<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-8da06bf elementor-widget elementor-widget-image\" data-id=\"8da06bf\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"746\" height=\"352\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig2.gif\" class=\"attachment-large size-large wp-image-1809\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 2: Typical block diagram of a rotational slide (from Dikau et al., 1996) <\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-605f938 elementor-widget elementor-widget-image\" data-id=\"605f938\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"594\" height=\"591\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig3.gif\" class=\"attachment-large size-large wp-image-1819\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 3: Oblique aerial photographs of the main scarp and multiple rotational landslides on the sea cliff at Stonebarrow Hill, Dorset, UK (from Dikau et al., 1996)\u00a0<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-b2b1310 elementor-widget elementor-widget-text-editor\" data-id=\"b2b1310\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>They may be single, multiple, with several movements of the same type close to each other, or successive, i.e. interlocking (Figure). Rotational slides can vary from terracettes with an area of only a few square meters (in this case, they are considered as shallow landslides) to large slides of several hectares.\u00a0<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-ef0cf9c elementor-widget elementor-widget-image\" data-id=\"ef0cf9c\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"526\" height=\"394\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig4a.gif\" class=\"attachment-large size-large wp-image-1824\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 4: Rotational earth slide in clay formation in the Panaro River valley, Northern Apennines, Italy (photos by D. Castaldini)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-2e5a47d elementor-widget elementor-widget-text-editor\" data-id=\"2e5a47d\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><strong>Translational slides<\/strong><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-8fe83e0 elementor-widget elementor-widget-image\" data-id=\"8fe83e0\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"632\" height=\"323\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig5.gif\" class=\"attachment-large size-large wp-image-1829\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 5: Schematic block diagram of a typical translational slide (from Dikau et al. 1996)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-1bf90a9 elementor-widget elementor-widget-text-editor\" data-id=\"1bf90a9\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>In translational slides, the material displaces along a planar or undulating surface of rupture, sliding out over the original ground surface. Translational slides often follow discontinuities more or less parallel to the slope, and are often superficial (such as contact between the rock and residual soils). Deeper, they occur along structural faults, joints, or bedding planes.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-31e7784 elementor-widget elementor-widget-image\" data-id=\"31e7784\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"335\" height=\"157\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Translationnal_slide.gif\" class=\"attachment-large size-large wp-image-1761\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-5cda50e elementor-widget elementor-widget-image\" data-id=\"5cda50e\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"394\" height=\"264\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig6.gif\" class=\"attachment-large size-large wp-image-1835\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 6: Cross-section and aerial view at Le Bouffay, northen France, displaying the translational horizontal slide and the subsequent collapse (from Maquaire, 1990)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-8f53eb7 elementor-widget elementor-widget-text-editor\" data-id=\"8f53eb7\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Translational slides on single discontinuities in rock masses have been called rock block slides (Figure 7g) or planar slides (Cruden and Varnes, 1996). Sometimes the surface of rupture may be formed by two discontinuities that cause the contained rock mass to displace down the line of intersection of the discontinuities, forming a wedge slide (Figure 7h). A stepped slide may result if two or more sets of discontinuities, such as bedding surfaces and some joint sets, penetrate the rock masses (Figure 7i).This type of slide is usually very rapid. Smooth discontinuities or thin clay levels may act as a lubricant; infiltration water reduces friction, triggers excess pore pressures and provokes the sliding of one rigid block on another.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-7a3834b elementor-widget elementor-widget-image\" data-id=\"7a3834b\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"203\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig7-1024x203.gif\" class=\"attachment-large size-large wp-image-1840\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig7-1024x203.gif 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig7-300x59.gif 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig7-768x152.gif 768w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 7: Different types of rock block slide (from Maquaire and Malet, 2006, adapted from Cruden and Varnes, 1996; Dikau et al., 1996)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-6f26176 elementor-widget elementor-widget-image\" data-id=\"6f26176\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"555\" height=\"313\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig8.gif\" class=\"attachment-large size-large wp-image-1845\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 8: Debris slide (from Maquaire and Malet, 2006, adapted from Cruden and Varnes, 1996; Dikau et al., 1996)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-de7739d elementor-widget elementor-widget-image\" data-id=\"de7739d\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"591\" height=\"638\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig9a.gif\" class=\"attachment-large size-large wp-image-1851\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-a834b51 elementor-widget elementor-widget-image\" data-id=\"a834b51\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"591\" height=\"603\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig9b.gif\" class=\"attachment-large size-large wp-image-1856\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-10ae604 figure-caption elementor-widget elementor-widget-text-editor\" data-id=\"10ae604\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p style=\"text-align: center;\">Translational slides can occur along soil-bedrock discontinuities or permeable\/impermeable soil junctions in slopes formed by coherent, fine soils or coarser debris. In this case, translational slides are termed soil slides, debris slides (Figure j) or slab slides. Debris slides and slab slides are normally shallow according to their length and width. Their velocities are linked to seasonal variations in groundwater levels and in the saturated conditions.<\/p><p style=\"text-align: center;\"><em>Figure 9: Oblique (on the left) and vertical (on the right) aerial photograph of the Bindon translational slide Devon, UK (from Dikau et al. 1996)<\/em><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-745fdd0 elementor-widget elementor-widget-image\" data-id=\"745fdd0\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"379\" height=\"283\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig10a.gif\" class=\"attachment-large size-large wp-image-1862\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-c4ea264 elementor-widget elementor-widget-image\" data-id=\"c4ea264\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"379\" height=\"283\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig10b.gif\" class=\"attachment-large size-large wp-image-1867\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-64d90c6 figure-caption elementor-widget elementor-widget-text-editor\" data-id=\"64d90c6\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p style=\"text-align: center;\"><em>Figure 10: Translational earth slide in predominantly fine material at Deva County, Romania (photos by D. Castaldini)<\/em><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-dd03c01 elementor-widget elementor-widget-image\" data-id=\"dd03c01\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"573\" height=\"394\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig11a.gif\" class=\"attachment-large size-large wp-image-1872\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-881234a elementor-widget elementor-widget-image\" data-id=\"881234a\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"426\" height=\"283\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig11b.gif\" class=\"attachment-large size-large wp-image-1877\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-6de0713 figure-caption elementor-widget elementor-widget-text-editor\" data-id=\"6de0713\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p style=\"text-align: center;\"><em>Figure 11: Translational rock slides occurred in November 1994 in Piemonte Apennines, Italy (Photos Archivio CNR IRPI, Torino)<\/em><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-c4ef837 elementor-widget elementor-widget-image\" data-id=\"c4ef837\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"724\" height=\"284\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig12.gif\" class=\"attachment-large size-large wp-image-1882\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 12: Panoramic views of the body and of the rock-slide surface of the Vajont landslide (from Dikau et al. 1996) Mudslide (or slump-earthflow)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-7f3e392 elementor-widget elementor-widget-image\" data-id=\"7f3e392\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"323\" height=\"188\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Mudslide.jpg\" class=\"attachment-large size-large wp-image-1772\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Mudslide.jpg 323w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Mudslide-300x175.jpg 300w\" sizes=\"(max-width: 323px) 100vw, 323px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 13: Mudslide (from Maquaire and Malet, 2006, adapted from Cruden and Varnes, 1996; Dikau et al., 1996)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-8d40bcb elementor-widget elementor-widget-image\" data-id=\"8d40bcb\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"584\" height=\"359\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig_14_Mudslide_Corps.jpg\" class=\"attachment-large size-large wp-image-1887\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig_14_Mudslide_Corps.jpg 584w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig_14_Mudslide_Corps-300x184.jpg 300w\" sizes=\"(max-width: 584px) 100vw, 584px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-47c661f figure-caption elementor-widget elementor-widget-text-editor\" data-id=\"47c661f\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p style=\"text-align: center;\">In some cases, a slide can change into a mudslide or slump-earthflow, especially on steep slopes, in highly tectonized clays or silty formations (Picarelli, 2001; Maquaire et al., 2003). As shown in figure 13, three morphological units can be distinguished: a primary source area with the main scarp and cracks, a track zone thinly covered by a flow (the paleotopography is still clearly discernible), and an accumulation zone, sometimes with several successive lobes.<\/p><p style=\"text-align: center;\"><em>Figure 14: Mudslide triggered near the town of Corps in the Spring of 2001 (Tri\u00e8ves, South Alps, France, May 2001).<\/em><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-5ca3681 elementor-widget elementor-widget-image\" data-id=\"5ca3681\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"590\" height=\"394\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig15.gif\" class=\"attachment-large size-large wp-image-1814\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 15: Lobate earthflow, 1969, Black Ven, Dorset, UK (from Dikau et al., 1996)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-e53d4fe elementor-widget elementor-widget-image\" data-id=\"e53d4fe\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"394\" height=\"590\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig14.gif\" class=\"attachment-large size-large wp-image-1893\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 16: Earthflow near Cortina d\u2019Ampezzo, Dolomites, E Alps, Italy (from Dikau et al., 1996)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-e4cb7c9 elementor-widget elementor-widget-image\" data-id=\"e4cb7c9\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"300\" height=\"313\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Rotational_slide3.gif\" class=\"attachment-large size-large wp-image-1899\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-5f4aa7e elementor-widget elementor-widget-image\" data-id=\"5f4aa7e\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"389\" height=\"283\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig17.gif\" class=\"attachment-large size-large wp-image-1904\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-4018de0 figure-caption elementor-widget elementor-widget-text-editor\" data-id=\"4018de0\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p style=\"text-align: center;\"><em>Figure 17: Boschi di Valoria earth flow, northern Apennines, Italy in 1996 (on the left) and in 2001 after its reactivation (on the rigth) (photos by A. Corsini)<\/em><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-0cd9da5 elementor-widget elementor-widget-image\" data-id=\"0cd9da5\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"378\" height=\"284\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig18.gif\" class=\"attachment-large size-large wp-image-1911\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 18: Super-Sauze earth flow, Alps, France (photo by M. Soldati) (see Case Study Super-Sauze)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-c373721 elementor-widget elementor-widget-text-editor\" data-id=\"c373721\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><strong>References:<\/strong><\/p><p>For the references herein and for knowing sources of didactic material go to 1.3 Selected references.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-9812\" class=\"elementor-tab-title\" data-tab=\"2\" role=\"tab\" aria-controls=\"elementor-tab-content-9812\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">2.1.2 More details on rapid movements<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-9812\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"2\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-9812\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"1918\" class=\"elementor elementor-1918\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-2db242e elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"2db242e\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-d873329\" data-id=\"d873329\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-cba6649 elementor-widget elementor-widget-text-editor\" data-id=\"cba6649\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Movements may accelerate suddenly and they can be subdivided into two groups, depending on whether the material is propagated as a mass or reworked. These movements are more difficult to monitor and control and are consequently a major threat to personal safety.<\/p><p>Tow groups of rapid movements can be distinguished, depending on whether the materials are propagated in a mass or reworked: The first comprises:<\/p><ul><li>rapid subsidence by rapid spontaneous collapse producing sinkholes or shafts caused by the rapid rupture of natural or artificial subterranean cave vaults,<\/li><li>fall: rock fall, stone fall, pebble fall, boulder fall, debris fall, soil fall arising from the mechanical development of cliffs or extensively fractured rocky escarpments,<\/li><li>rockfall avalanche, topple, rockslide, of slabs from cliffs or rocky escarpments, depending on pre-existing discontinuity slabs,<\/li><\/ul><p><strong>Rapid subsidence<\/strong><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-f3b1e2c elementor-widget elementor-widget-image\" data-id=\"f3b1e2c\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"556\" height=\"338\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Rapid_subsidence_scheme_eng.jpg\" class=\"attachment-large size-large wp-image-1922\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Rapid_subsidence_scheme_eng.jpg 556w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Rapid_subsidence_scheme_eng-300x182.jpg 300w\" sizes=\"(max-width: 556px) 100vw, 556px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-533de52 elementor-widget elementor-widget-text-editor\" data-id=\"533de52\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Rapid subsidence is the process of brutal spontaneous collapse producing sinkholes or shafts caused by the rapid rupture of natural or artificial subterranean cave vaults (subterranean quarry or mines -iron, salt, coal, etc.-). Go to 2.1.2.1 More information on rapid subsidence<\/p><p><strong>Fall<\/strong><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-5398613 elementor-widget elementor-widget-image\" data-id=\"5398613\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"790\" height=\"292\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fall.jpg\" class=\"attachment-large size-large wp-image-1927\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fall.jpg 790w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fall-300x111.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fall-768x284.jpg 768w\" sizes=\"(max-width: 790px) 100vw, 790px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-61ec543 elementor-widget elementor-widget-text-editor\" data-id=\"61ec543\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Generally the mass is detached from a very steep slope along a surface on which little or no shear displacement takes place. It occurs mainly in the air and the phenomenon includes the material&rsquo;s free fall, saltation, bouncing and rolling. Go to 2.1.2.2 More information on fall&gt;&gt;<\/p><p><strong>Rockfall avalanche<\/strong><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-0432018 elementor-widget elementor-widget-image\" data-id=\"0432018\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"518\" height=\"317\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Topple.jpg\" class=\"attachment-large size-large wp-image-1932\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Topple.jpg 518w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Topple-300x184.jpg 300w\" sizes=\"(max-width: 518px) 100vw, 518px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-6bf9833 elementor-widget elementor-widget-text-editor\" data-id=\"6bf9833\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>The movement is due to stresses which cause a toppling momentum around a rotation point situated below the centre of gravity of the rock mass affected. The phenomenon can evolve into either a fall (rapid movement) or slide (slow deformation).<\/p><p>Go to 2.1.2.4 More information on topple<\/p><p>The second group corresponds to the flow phenomenon. Flow is characterised by continuous movements in space fall within this class; in them the shear surfaces (or thin zones of distributed shear) are short-lived, closely spaced and not usually preserved. From the kinematic standpoint the movement could be compared to that of a viscous fluid.<\/p><p>This second group comprises:<\/p><ul><li>debris flow arising from the transport of material in viscous or fluid flows in mountain stream beds or on hillslopes for the debris avalanche,<\/li><li>mudslide or slump-earthflow, mudflow, soil flow, generally due to the evolution of the front of landslips. Their propagation mode is somewhere between mass displacement and viscous or fluid transport.<\/li><\/ul><p><strong>Debris flow and debris avalanche:<\/strong><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-cec11a7 elementor-widget elementor-widget-image\" data-id=\"cec11a7\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"392\" height=\"248\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Picture11.gif\" class=\"attachment-large size-large wp-image-1937\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-28275b9 elementor-widget elementor-widget-image\" data-id=\"28275b9\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"568\" height=\"331\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/debris_avalanche.jpg\" class=\"attachment-large size-large wp-image-1942\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/debris_avalanche.jpg 568w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/debris_avalanche-300x175.jpg 300w\" sizes=\"(max-width: 568px) 100vw, 568px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-abba53a elementor-widget elementor-widget-text-editor\" data-id=\"abba53a\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Debris flow is a very rapid to extremely rapid flow (&gt; 1 m.s-1) of saturated non-plastic debris in a steep channel (Figure 1.m). The key characteristic of a debris flow is the presence of an established channel or regular confined path, unlike debris avalanches which are thin, partly or totally saturated, and which occur on hillslopes.<\/p><p>Go to 2.1.2.5. More information on flow (debris flow and debris avalanche)<\/p><p><strong>Mudflow (soil flow)<\/strong><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-d14a0d1 elementor-widget elementor-widget-image\" data-id=\"d14a0d1\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"466\" height=\"281\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Picture14.gif\" class=\"attachment-large size-large wp-image-1947\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-64beb61 elementor-widget elementor-widget-text-editor\" data-id=\"64beb61\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Small mudflow (from Dikau et al., 1996)<\/p><p><strong>Soil flows<\/strong>\u00a0occur in wet sands or in silty-clays which are so reworked with water or so liquefied by structural collapse that they adopt a flow mode (Locat and Leroueil, 1997; Hight et al., 1998). A common term used for these conditions is mudflow. These are similar in form and behaviour to debris flows.<\/p><p>Go to 2.1.2.5 More information on flow (mudlow or soil flow)<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-5205403 elementor-widget elementor-widget-accordion\" data-id=\"5205403\" data-element_type=\"widget\" data-widget_type=\"accordion.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<div class=\"elementor-accordion\" role=\"tablist\">\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-8601\" class=\"elementor-tab-title\" data-tab=\"1\" role=\"tab\" aria-controls=\"elementor-tab-content-8601\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">2.1.2.1 More information on rapid subsidence<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-8601\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"1\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-8601\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"1953\" class=\"elementor elementor-1953\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-0cc09c4 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"0cc09c4\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-bac389e\" data-id=\"bac389e\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-3a5975e elementor-widget elementor-widget-image\" data-id=\"3a5975e\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"556\" height=\"338\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Rapid_subsidence_scheme_eng.jpg\" class=\"attachment-large size-large wp-image-1922\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Rapid_subsidence_scheme_eng.jpg 556w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Rapid_subsidence_scheme_eng-300x182.jpg 300w\" sizes=\"(max-width: 556px) 100vw, 556px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Rapid subsidence scheme (from Maquaire, 2005)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-6455a80 elementor-widget elementor-widget-text-editor\" data-id=\"6455a80\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Rapid subsidence is the process of brutal spontaneous collapse producing sinkholes or shafts caused by the rapid rupture of natural or artificial subterranean cave vaults (subterranean quarry or mines -iron, salt, coal, etc.-).<\/p><p><strong>What is a rapid subsidence process?<\/strong><\/p><p>Rapid subsidence is a brutal spontaneous collapse producing sinkholes or shafts of a more or less large extent (diameter of a few meters to several hectares) and a variable depth (a few meters to many hundreds of meters). Rapid subsidence can occur after a progressive subsidence. Commonly, rapid subsidence occurs above man-made voids, such as tunnels, wells and covered subterranean quarries or mines (iron, salt, coal, etc.) It is also frequent in karst terrains, where dissolution of limestone by fluid flow in the subsurface causes the creation of voids (i.e. caves). If the roof of these voids becomes too weak, it can collapse and the overlying rock and earth will fall into the space, causing subsidence at the surface.<\/p><p>In uban zones, rapid subsidence can cause numerous victims. A well known disaster occurred in 1958 in Roosburg (Belgium) when 18 people were killed by a tunnel collapse of an ancient subterranean quarry. In Clamart and Issy-les-Moulineaux (France), 21 people died as an ancient subterranean quarry collapsed in 1961.<\/p><p><strong>Why and how does the collapsing happen?<\/strong><\/p><p>The Process of roof collapsing<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-809a851 elementor-widget elementor-widget-image\" data-id=\"809a851\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"190\" height=\"324\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/roofcollapsing1b.jpg\" class=\"attachment-large size-large wp-image-1961\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/roofcollapsing1b.jpg 190w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/roofcollapsing1b-176x300.jpg 176w\" sizes=\"(max-width: 190px) 100vw, 190px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-67f0749 elementor-widget elementor-widget-image\" data-id=\"67f0749\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"367\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/roofcollapsing1c-1024x367.jpg\" class=\"attachment-large size-large wp-image-1956\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/roofcollapsing1c-1024x367.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/roofcollapsing1c-300x107.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/roofcollapsing1c-768x275.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/roofcollapsing1c.jpg 1027w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Schemes of the process of roof collapsing from subterranean cave: 1. Degradation of the roof of the gallery; 2. Roof fall down; 3 &amp; 4. Development of roof collapsing; 4. The roof collapsing is not detected and reached the surface.<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-2014ef3 elementor-widget elementor-widget-text-editor\" data-id=\"2014ef3\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>When a funnel or a shallow hole of a few meters of diameter and a few meters of depth suddenly occurs at the surface it is scientifically termed roof collapsing. Its dimensions depend on the size of the void and the nature of the bedrock which separates it from the surface.<\/p><p>How does this happen? For example, in the beginning there may be a gallery consisting of several vaults. These vaults may increase little by little until they finally reach the surface. Still, the roof collapsing will not occur if the gallery is sufficiently deep, because the expansion of the blocks of the roof comes to fill the void before it does not reach surface. The hazard\/threat of roof collapsing is reduced if a thick and resistant bench stops progressive degradation<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-31ad635 elementor-widget elementor-widget-image\" data-id=\"31ad635\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"396\" height=\"264\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/1Picture20.gif\" class=\"attachment-large size-large wp-image-1981\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Roof collapsing above subterranean caves in limestone, Pays d\u2019Auge, Normandy, France (Photo : O. Maquaire, Cerg)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-3830262 elementor-widget elementor-widget-image\" data-id=\"3830262\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"394\" height=\"265\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/1Picture21.gif\" class=\"attachment-large size-large wp-image-1976\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-25fa728 elementor-widget elementor-widget-image\" data-id=\"25fa728\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"395\" height=\"264\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/1Picture22.gif\" class=\"attachment-large size-large wp-image-1971\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-7700ffa figure-caption elementor-widget elementor-widget-text-editor\" data-id=\"7700ffa\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p style=\"text-align: center;\"><em>Subterranean carrier in limestone (Tours, France): progressive degradation of the pillar (diminution of its width) and roof fall (Photos: O. Maquaire, CERG).<\/em><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-760079d elementor-widget elementor-widget-image\" data-id=\"760079d\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"393\" height=\"265\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/1Picture23.gif\" class=\"attachment-large size-large wp-image-1966\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Karstic network in Jurassic limestones near Port-en-Bessin, Normandy (Photo: O. Maquaire, CERG)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-6a29c0c elementor-widget elementor-widget-text-editor\" data-id=\"6a29c0c\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><strong>References<\/strong><\/p><p>C\u00f4te, PH., fauchard, C., Poth\u00e9rat, P. (2005). M\u00e9thodes g\u00e9ophysiques pour la localisation de cavit\u00e9s souterraines : potentialit\u00e9s et limites. In Evaluation et gestion des risques li\u00e9s aux carri\u00e8res souterraines abandonn\u00e9es. Actes des journ\u00e9es scientifiques du LCPC, pp. 8-17.<\/p><p>Embleton, C., and Embleton C. (eds.) (1997), Geomorphological Hazards of Europe. Developments in Earth Surface Processes 5. Amsterdam : Elsevier, 524p.<\/p><p>Flageollet, J. C. (1988), Les mouvements de terrain et leur pr\u00e9vention, Paris : Masson, 224p. LCPC (2000). Guide technique pour la caract\u00e9risation et cartographie de l\u2019al\u00e9a d\u00fb aux mouvements de terrain. Collection \u2018les risques naturels\u2019.<\/p><p>Laboratoire Central des Ponts et Chauss\u00e9es, 91 p.<\/p><p>Maquaire, O., (2005). Geomorphic hazards and natural risks, In: Koster, E., A. (ed.), The Physical Geography of Western Europe, Oxford Regional Environments, Oxford University Press, Chapter 18, 354-377.<\/p><p>Minist\u00e8re de l\u2019Environnement, 1997, Plans de pr\u00e9vention des risques naturels (PPR) : guide g\u00e9n\u00e9ral.. La Documentation Fran\u00e7aise, Paris, 76p.<\/p><p>Minist\u00e8re de l\u2019Environnement, 1999, Plans de pr\u00e9vention des risques naturels (PPR) : risques de mouvements de terrain. Guide m\u00e9thodologique.. La Documentation Fran\u00e7aise, Paris, 71p.<\/p><p>Minist\u00e8re de l\u2019Ecologie et du D\u00e9veloppement Durable, 2004. Dossier d\u2019information sur le risque Mouvement de terrains, 20 p. (\u00e0 t\u00e9l\u00e9charger sur site du MEDD).<\/p><p>Poth\u00e9rat, P. (2005). L\u2019op\u00e9ration de recherche \u00ab Carri\u00e8res souterraines abandonn\u00e9es \u00bb. Localisation, dignostic de stabilit\u00e9, gestion. Rapport de synth\u00e8se. G\u00e9otechnique et risques naturels, GT 77. LCPC, 132 p.<\/p><p><strong>Internet Links:<\/strong><\/p><p><a href=\"http:\/\/fr.wikipedia.org\/wiki\/Subsidence\" target=\"_blank\" rel=\"noopener\">http:\/\/fr.wikipedia.org\/wiki\/Subsidence<\/a><\/p><p><a href=\"http:\/\/www.lorraine.drire.gouv.fr\/mines\/g_cadreDomaine.asp?droite=2_ApresMines.asp&amp;bas=g_MinesNavig.asp?DEST=APMINES\" target=\"_blank\" rel=\"noopener\">http:\/\/www.lorraine.drire.gouv.fr\/mines\/g_cadreDomaine.asp?droite=2_ApresMines.asp&amp;bas=g_MinesNavig.asp?DEST=APMINES<\/a><\/p><p><a href=\"http:\/\/www.cgm.org\/themes\/soussol\/mines\/\" target=\"_blank\" rel=\"noopener\">http:\/\/www.cgm.org\/themes\/soussol\/mines\/<\/a><\/p><p><a href=\"http:\/\/www.cavite.net\/\" target=\"_blank\" rel=\"noopener\">http:\/\/www.cavite.net<\/a><\/p><p><a href=\"http:\/\/www.prim.net\/professionnel\/documentation\/dossiers_info\/nat\/low\/mouvtTerr.pdf\" target=\"_blank\" rel=\"noopener\">http:\/\/www.prim.net\/professionnel\/documentation\/dossiers_info\/nat\/low\/mouvtTerr.pdf<\/a><\/p><p><a href=\"http:\/\/www.catp-asso.org\/cavites37\/pages\/missions.htm\" target=\"_blank\" rel=\"noopener\">http:\/\/www.catp-asso.org\/cavites37\/pages\/missions.htm<\/a><\/p><p><a href=\"http:\/\/clamart.cyberkata.org\/\" target=\"_blank\" rel=\"noopener\">http:\/\/clamart.cyberkata.org\/<\/a><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-8602\" class=\"elementor-tab-title\" data-tab=\"2\" role=\"tab\" aria-controls=\"elementor-tab-content-8602\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">2.1.2.2 More information on fall<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-8602\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"2\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-8602\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"1987\" class=\"elementor elementor-1987\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-bb10051 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"bb10051\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-75ad654\" data-id=\"75ad654\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-962677e elementor-widget elementor-widget-text-editor\" data-id=\"962677e\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Fall<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-7e757b7 elementor-widget elementor-widget-image\" data-id=\"7e757b7\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"311\" height=\"114\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fall_01.jpg\" class=\"attachment-large size-large wp-image-1991\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fall_01.jpg 311w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fall_01-300x110.jpg 300w\" sizes=\"(max-width: 311px) 100vw, 311px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-eb96acb elementor-widget elementor-widget-text-editor\" data-id=\"eb96acb\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Generally the mass is detached from a very steep slope along a surface on which little or no shear displacement takes place. It occurs mainly in the air and the phenomenon includes the material&rsquo;s free fall, saltation, bouncing and rolling.<\/p><p><strong>What is a fall phenomenon?<\/strong><\/p><p>(Extract from Maquaire and Malet, 2006)<\/p><p>Falls (and also topples) comprise a free movement of material from steep slopes or cliffs. A topple is very similar to a fall in many aspects, but normally involves a pivoting action rather than a complete separation at the base of the failure.<\/p><p>Their general characteristics are as follows: the shape of the rupture surface is usually smooth and vertical; the material falls suddenly from a main scarp following a preparation phase during which a slice of material is separated, damaging the intact mass; the volume and size of the fallen material are extremely variable, depending on the morpho-structural and lithological conditions of the slope. These phenomena occur on cliffs when the base is eroded by the action of the sea or of rivers. The falls are always sudden and very quick, while topples vary in speed from extremely slow to extremely quick, with acceleration and deceleration phases (Maquaire and Malet, 2006).<\/p><p>A fall starts with the detachment of rock or soil from a steep slope along a surface on which little or no shear displacement takes place. The trajectory of the fallen material is rectilinear and vertical for slopes with an inclination of more than 70\u00b0 (Cruden et Varnes, 1996).<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-4546944 elementor-widget elementor-widget-image\" data-id=\"4546944\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"218\" height=\"162\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fall_02.jpg\" class=\"attachment-large size-large wp-image-1996\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-f16539b elementor-widget elementor-widget-text-editor\" data-id=\"f16539b\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>For a rock fall, material on slopes with an inclination of between 45 and 70\u00b0 moves by successive rebounds, depending on the size of the material, the restitution coefficient and the angle between the slope and the trajectory of the falling mass. Throughout the length of slopes of less than 45\u00b0 the falling material may roll. In the latter two cases, the material, which is very mobile, may move considerable distances from the source zone. Debris falls and soil falls are typically shallow landslides. Debris and soil falls are triggered in loose materials and their volume varies from a few cubic metres to tens of cubic metres. The accumulated material, which is not consolidated, may be easily mobilized and transported.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-c938f7a elementor-widget elementor-widget-image\" data-id=\"c938f7a\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"394\" height=\"264\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fall_03.jpg\" class=\"attachment-large size-large wp-image-2001\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fall_03.jpg 394w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fall_03-300x201.jpg 300w\" sizes=\"(max-width: 394px) 100vw, 394px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 1: Block diagram of a typical coastal rock fall (from Dikau et al., 1996)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-00630ff elementor-widget elementor-widget-image\" data-id=\"00630ff\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"336\" height=\"237\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fall_04.jpg\" class=\"attachment-large size-large wp-image-2007\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fall_04.jpg 336w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fall_04-300x212.jpg 300w\" sizes=\"(max-width: 336px) 100vw, 336px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-370e19b elementor-widget elementor-widget-image\" data-id=\"370e19b\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"342\" height=\"232\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fall_05.jpg\" class=\"attachment-large size-large wp-image-2012\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fall_05.jpg 342w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fall_05-300x204.jpg 300w\" sizes=\"(max-width: 342px) 100vw, 342px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-a3bcc52 figure-caption elementor-widget elementor-widget-text-editor\" data-id=\"a3bcc52\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p style=\"text-align: center;\"><em>Fig. 2: Ma\u00e8 Valley (NE Italian Alps): January 1985 rock fall (Archivio CNR &#8211; IRPI, Padova)<\/em><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-6490861 elementor-widget elementor-widget-image\" data-id=\"6490861\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"375\" height=\"282\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fall_06.jpg\" class=\"attachment-large size-large wp-image-2017\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fall_06.jpg 375w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fall_06-300x226.jpg 300w\" sizes=\"(max-width: 375px) 100vw, 375px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-4a1bc2f elementor-widget elementor-widget-image\" data-id=\"4a1bc2f\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"372\" height=\"279\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fall_07.jpg\" class=\"attachment-large size-large wp-image-2022\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fall_07.jpg 372w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fall_07-300x225.jpg 300w\" sizes=\"(max-width: 372px) 100vw, 372px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-bf0dab3 figure-caption elementor-widget elementor-widget-text-editor\" data-id=\"bf0dab3\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p style=\"text-align: center;\"><em>Fig. 3: Rock fall in progress at Piz Sompluf peak, Dolomites, NE italian Alps (photos Summer 2006, from Archivio Provincia di Bolzano)<\/em><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-68235cf elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"68235cf\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-99b2548\" data-id=\"99b2548\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-626128d elementor-widget elementor-widget-image\" data-id=\"626128d\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"252\" height=\"337\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fall_08.jpg\" class=\"attachment-large size-large wp-image-2027\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fall_08.jpg 252w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fall_08-224x300.jpg 224w\" sizes=\"(max-width: 252px) 100vw, 252px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 4: Pietra di Bismantova (Northern Apennines, Italy): big boulders of a relict rock fall (photo by D. Castaldini)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-7ec513f elementor-widget elementor-widget-image\" data-id=\"7ec513f\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"336\" height=\"260\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fall_09.jpg\" class=\"attachment-large size-large wp-image-2032\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fall_09.jpg 336w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fall_09-300x232.jpg 300w\" sizes=\"(max-width: 336px) 100vw, 336px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-ac6fb70 elementor-widget elementor-widget-image\" data-id=\"ac6fb70\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"311\" height=\"276\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fall_10.jpg\" class=\"attachment-large size-large wp-image-2037\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fall_10.jpg 311w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fall_10-300x266.jpg 300w\" sizes=\"(max-width: 311px) 100vw, 311px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-ee070f6 figure-caption elementor-widget elementor-widget-text-editor\" data-id=\"ee070f6\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p style=\"text-align: center;\"><em>Fig. 5: Randa rockfalls, Switzerland, occurred on 18th April, 9th May 1991. The events blocked the road, rail way and river which have subsequently been diverted (from Dikau et al., 1996)<\/em><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-6815045 elementor-widget elementor-widget-image\" data-id=\"6815045\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"390\" height=\"296\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fall_11.jpg\" class=\"attachment-large size-large wp-image-2042\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fall_11.jpg 390w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fall_11-300x228.jpg 300w\" sizes=\"(max-width: 390px) 100vw, 390px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-adc7a1f elementor-widget elementor-widget-image\" data-id=\"adc7a1f\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"386\" height=\"290\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fall_12.jpg\" class=\"attachment-large size-large wp-image-2047\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fall_12.jpg 386w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fall_12-300x225.jpg 300w\" sizes=\"(max-width: 386px) 100vw, 386px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-3bda7af figure-caption elementor-widget elementor-widget-text-editor\" data-id=\"3bda7af\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p style=\"text-align: center;\"><em>Fig. 6: Rockfall at the west coast of Zakynthos Island Greece (Photo by M. Soldati)<\/em><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-0c46daf elementor-widget elementor-widget-image\" data-id=\"0c46daf\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"373\" height=\"280\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fall_13.jpg\" class=\"attachment-large size-large wp-image-2052\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fall_13.jpg 373w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fall_13-300x225.jpg 300w\" sizes=\"(max-width: 373px) 100vw, 373px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 7: Big boulders due to rockfalls at the northwestern coast of Malta Island (Photo by M. Soldati)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-a923e81 elementor-widget elementor-widget-image\" data-id=\"a923e81\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"352\" height=\"264\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fall_14.jpg\" class=\"attachment-large size-large wp-image-2057\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fall_14.jpg 352w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fall_14-300x225.jpg 300w\" sizes=\"(max-width: 352px) 100vw, 352px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 8: Big boulders due to rock fall at Ericeira, central coast of Portugal (photo by D. Castaldini)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-67a124d elementor-widget elementor-widget-text-editor\" data-id=\"67a124d\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><strong>References:<\/strong><\/p><p>For the references herein and for knowing sources of didactic material go to1.3 Selected references<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-8603\" class=\"elementor-tab-title\" data-tab=\"3\" role=\"tab\" aria-controls=\"elementor-tab-content-8603\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">2.1.2.3 More information on rockfall avalanche<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-8603\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"3\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-8603\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"2063\" class=\"elementor elementor-2063\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-b3b2720 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"b3b2720\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-749dbe0\" data-id=\"749dbe0\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-0eba85e elementor-widget elementor-widget-image\" data-id=\"0eba85e\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"430\" height=\"217\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Picture9.gif\" class=\"attachment-large size-large wp-image-2066\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-b1ff573 elementor-widget elementor-widget-text-editor\" data-id=\"b1ff573\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>A rock avalanche is a large bulk of mostly dry rock debris deriving from the collapse of a slope or cliff and moving at a high velocity and for a long distance, even on a gentle slope.<\/p><p><strong>What is a rockfall avalanche?<\/strong><\/p><p>(Extract from Dikau et al., 1996)<\/p><p>A rock avalanche is a large bulk of mostly dry rock debris deriving from the collapse of a slope or cliff and moving at a high velocity and for a long distance, even on a gentle slope. Its speed can be in the order of tens of meters per second, the travel distance in the order of kilometres. In the area of accumulation, its volume can exceed 1 x 106 m3, covering a total surface of over 0.1 km\u00b2. Owing to its velocity and dimensions, this kind of landslide can be extremely costly in terms of human lives.<\/p><p>The rock avalanche can develop in two ways: first, by the fall or slide of a rock body which during movement progressively looses its cohesion by turning into dry debris and thus continues its advancement as a debris avalanche; secondly, by the sudden mobilisation of a debris avalanche, debris flow, either because of the fall of an overhanging rock mass or because of a seismic shock.<\/p><p><strong>The Valpola rockfall avalanche (Italy): 28 July 1987<\/strong><\/p><p>For the latter it is important to describe the phases that occurred on 28 July 1987 which led to be sliding of a portion of Mont Zandila in Valtellina (Italian Central Alp). At 7:25 a.m., after a preliminary phase lasting less than four days and without any sign of preceding seismic events, the detachment of a large rock volume of about 34 million cubic meters suddenly occurred. Although the collapse took place at a great velocity, its main phases of development can nevertheless be reconstructed thanks to direct witnesses and morphological evidence recorded after the event:<\/p><ul><li>The first displacements, which were relatively limited in volume, happened because of a progressive uphill widening of the crown generated by the falls occurring an hour earlier;<\/li><li>After a few seconds, the entire rock mass started to slide along two main shear panes: the first was known to have 45\u00b0 dip to the east, the second was a neo-formation plane dipping 35\u00b0 to the north;<\/li><li>Along the latter plane, the translational movements to the north, that is, toward the deep valley-floor of Valpola, took place initially with a series of short successive impulses and progressively increasing accelerations until it eventually came to a stop after the impact with a rock bluff which bordered the unstable slope. The thickness of the rock body that came into collision was estimated to be in excess of 70 m;\u00a0<\/li><li>Following the impact, the displaced rock, which up to that moment had remained fairly compact, was subdivided into several fragments of various dimensions, falling to the valley-floor in an easterly direction from altitudes ranging from 600 to 850 m. Therefore during this phase the gravitational event which had started as a slide, rapidly turned into rock avalanche, involving in its movement also the wood cover and the debris deposits distributed along the underlying slope. The fragmented collapsed rocks, after having obstructed a large area of the valley-floor, went up the opposite slope to a height of about 300 m, preceded by a cloud of dust which raised an altitude of 200 m.<\/li><\/ul><p>A portion of the collapsed material fell into a previously formed barrier-lake, causing a mud wave which destroyed the village of Aquilone, located a few kilometres upstream, and claimed several lives. The volume of the accumulation deposit was estimated as 40 million m3, with a maximum thickness of 90 m. On the surface of the landslide deposit the finer fraction was composed of millimetre to decimetre fragments, while the coarser material was concentrated along the flanks of the mass movement route.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-0b68df8 elementor-widget elementor-widget-image\" data-id=\"0b68df8\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"774\" height=\"1024\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/7_1-774x1024.jpg\" class=\"attachment-large size-large wp-image-2071\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/7_1-774x1024.jpg 774w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/7_1-227x300.jpg 227w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/7_1-768x1017.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/7_1.jpg 868w\" sizes=\"(max-width: 774px) 100vw, 774px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-660f3f1 elementor-widget elementor-widget-image\" data-id=\"660f3f1\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"264\" height=\"394\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Valpola_rockavalanchec.jpg\" class=\"attachment-large size-large wp-image-2076\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Valpola_rockavalanchec.jpg 264w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Valpola_rockavalanchec-201x300.jpg 201w\" sizes=\"(max-width: 264px) 100vw, 264px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-1372355 figure-caption elementor-widget elementor-widget-text-editor\" data-id=\"1372355\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p style=\"text-align: center;\"><em>Fig. 1: The Valpola rock avalanche occurred on 28 July 1987 in the Italian Central Alps: left, aerial view to the west; right, general view to the south (from Dikau et al., 1996)<\/em><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-8604\" class=\"elementor-tab-title\" data-tab=\"4\" role=\"tab\" aria-controls=\"elementor-tab-content-8604\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">2.1.2.4 More information on topple<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-8604\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"4\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-8604\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"2082\" class=\"elementor elementor-2082\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-f88c5e7 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"f88c5e7\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-d0ea257\" data-id=\"d0ea257\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-d1a3e66 elementor-widget elementor-widget-text-editor\" data-id=\"d1a3e66\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><strong>Topple:<\/strong><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-b02e3c7 elementor-widget elementor-widget-image\" data-id=\"b02e3c7\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"518\" height=\"317\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Topple.jpg\" class=\"attachment-large size-large wp-image-1932\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Topple.jpg 518w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Topple-300x184.jpg 300w\" sizes=\"(max-width: 518px) 100vw, 518px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-f871e44 elementor-widget elementor-widget-text-editor\" data-id=\"f871e44\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>The movement is due to stresses which cause a toppling momentum around a rotation point situated below the centre of gravity of the rock mass affected. The phenomenon can evolve into either a fall or slide.<\/p><p><strong>What is a topple phenomenon?<\/strong><\/p><p>(Extract from Maquaire and Malet, 2006)<\/p><p>Topples (and also falls) comprise a free movement of material from steep slopes or cliffs. A topple is very similar to a fall in many aspects, but normally involves a pivoting action rather than a complete separation at the base of the failure.<\/p><p>Their general characteristics are as follows: the shape of the rupture surface is usually smooth and vertical; the material falls suddenly from a main scarp following a preparation phase during which a slice of material is separated, damaging the intact mass; the volume and size of the fallen material are extremely variable, depending on the morpho-structural and lithological conditions of the slope. These phenomena occur on cliffs when the base is eroded by the action of the sea or of rivers. The falls are always sudden and very quick, while topples vary in speed from extremely slow to extremely quick, with acceleration and deceleration phases (Maquaire and Malet, 2006).<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-a24b375 elementor-widget elementor-widget-image\" data-id=\"a24b375\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"588\" height=\"121\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/tropple_2.jpg\" class=\"attachment-large size-large wp-image-2086\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/tropple_2.jpg 588w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/tropple_2-300x62.jpg 300w\" sizes=\"(max-width: 588px) 100vw, 588px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 1: Different types of topple (from Maquaire and Malet, 2006 adapted from Cruden and Varnes, 1996; Dikau et al., 1996;)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-dc6ace6 elementor-widget elementor-widget-text-editor\" data-id=\"dc6ace6\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>A topple is the forward rotation of a mass of rock or soil about an axis located below the centre of gravity of the displaced mass (Figure 1.c). Topples may lead to falls or slides of the displaced mass, depending on the geometry of the rupture surface and the orientation and extent of the kinematically active discontinuities. Cruden and Varnes (1996) state that the way in which topples occur may be very varied: flexural toppling occurs in rocks with one preferred discontinuity system, oriented to present a rock slope with semi-continuous cantilever beams which may develop into retrogressive complex rock topple-rock fall (Figure 1.d); block toppling occurs where the individual columns are divided by widely-spaced joints; chevron toppling occurs along complex structural configuration, where the change of dip is concentrated at the surface of rupture to give a complex rock topple-rock slide (Figure 1.e).<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-a302332 elementor-widget elementor-widget-image\" data-id=\"a302332\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"276\" height=\"265\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/tropple_3.jpg\" class=\"attachment-large size-large wp-image-2092\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 2: Typical block diagram of a topple (from Dikau et al., 1996)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-f1490fe elementor-widget elementor-widget-image\" data-id=\"f1490fe\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"267\" height=\"400\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/tropple_4.jpg\" class=\"attachment-large size-large wp-image-2097\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/tropple_4.jpg 267w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/tropple_4-200x300.jpg 200w\" sizes=\"(max-width: 267px) 100vw, 267px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 3: Topple in limestone Rheinland-Pflaz, Germany (from Dikau et al. 1996)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-3913591 elementor-widget elementor-widget-image\" data-id=\"3913591\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"266\" height=\"399\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/tropple_5.jpg\" class=\"attachment-large size-large wp-image-2102\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/tropple_5.jpg 266w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/tropple_5-200x300.jpg 200w\" sizes=\"(max-width: 266px) 100vw, 266px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 4: Toppling failure at Vera, Almeria, Spain (from Dikau et al. 1996)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-da7c460 elementor-widget elementor-widget-image\" data-id=\"da7c460\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"383\" height=\"378\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/tropple_6.jpg\" class=\"attachment-large size-large wp-image-2108\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/tropple_6.jpg 383w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/tropple_6-300x296.jpg 300w\" sizes=\"(max-width: 383px) 100vw, 383px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 5: Tension crack toppling affecting sea cliffs at Stonebarrow Hill, West Dorset, UK (from Dikau et al., 1996)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-50838cb elementor-widget elementor-widget-text-editor\" data-id=\"50838cb\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><strong>References:<\/strong><\/p><p>For the references herein and for knowing sources of didactic material go to 1.3 Selected references\u00a0<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-8605\" class=\"elementor-tab-title\" data-tab=\"5\" role=\"tab\" aria-controls=\"elementor-tab-content-8605\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">2.1.2.5 More information on flow<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-8605\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"5\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-8605\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"2114\" class=\"elementor elementor-2114\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-bf5b585 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"bf5b585\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-d827980\" data-id=\"d827980\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-d1cbf0d elementor-widget elementor-widget-text-editor\" data-id=\"d1cbf0d\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><strong>What is a flow phenomenon?<\/strong><br \/>(Extract from Maquaire and Malet, 2006)<\/p><p>A flow is a landslide in which the individual particles travel separately within a moving mass. Unlike slides, occurring along more or less well-defined shear zones, flow-like landslides are characterised by internal differential movements that are distributed throughout the mass (Picarelli, 2001). Their flow-like morphologies are much longer than they are wide and their uneven topography shows successive lobes. They have a considerable erosive capacity and can carry material eroded from slopes or banks over considerable distances and cover sizeable surfaces with varying thicknesses. They contribute to positive erosion balances, as the material can be carried outside the slope basin. Coussot (1993) suggests a rheological classification of these flows. Hungr et al. (2001) distinguish several types of shallow flow-like landslides.<\/p><p><strong>Debris flow and debris avalanche:<\/strong><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-c81d011 elementor-widget elementor-widget-gallery\" data-id=\"c81d011\" data-element_type=\"widget\" data-settings=\"{&quot;gallery_layout&quot;:&quot;justified&quot;,&quot;lazyload&quot;:&quot;yes&quot;,&quot;ideal_row_height&quot;:{&quot;unit&quot;:&quot;px&quot;,&quot;size&quot;:200,&quot;sizes&quot;:[]},&quot;ideal_row_height_tablet&quot;:{&quot;unit&quot;:&quot;px&quot;,&quot;size&quot;:150,&quot;sizes&quot;:[]},&quot;ideal_row_height_mobile&quot;:{&quot;unit&quot;:&quot;px&quot;,&quot;size&quot;:150,&quot;sizes&quot;:[]},&quot;gap&quot;:{&quot;unit&quot;:&quot;px&quot;,&quot;size&quot;:10,&quot;sizes&quot;:[]},&quot;gap_tablet&quot;:{&quot;unit&quot;:&quot;px&quot;,&quot;size&quot;:10,&quot;sizes&quot;:[]},&quot;gap_mobile&quot;:{&quot;unit&quot;:&quot;px&quot;,&quot;size&quot;:10,&quot;sizes&quot;:[]},&quot;link_to&quot;:&quot;file&quot;,&quot;overlay_background&quot;:&quot;yes&quot;,&quot;content_hover_animation&quot;:&quot;fade-in&quot;}\" data-widget_type=\"gallery.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<div class=\"elementor-gallery__container\">\n\t\t\t\t\t\t\t<a class=\"e-gallery-item elementor-gallery-item elementor-animated-content\" href=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Picture11.gif\" data-elementor-open-lightbox=\"yes\" data-elementor-lightbox-slideshow=\"all-c81d011\" data-elementor-lightbox-title=\"Picture11\" data-e-action-hash=\"#elementor-action%3Aaction%3Dlightbox%26settings%3DeyJpZCI6MTkzNywidXJsIjoiaHR0cHM6XC9cL2Jlc2FmZW5ldC5uZXRcL3dwLWNvbnRlbnRcL3VwbG9hZHNcLzIwMjBcLzExXC9QaWN0dXJlMTEuZ2lmIiwic2xpZGVzaG93IjoiYWxsLWM4MWQwMTEifQ%3D%3D\">\n\t\t\t\t\t<div class=\"e-gallery-image elementor-gallery-item__image\" data-thumbnail=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Picture11.gif\" data-width=\"392\" data-height=\"248\" aria-label=\"\" role=\"img\" ><\/div>\n\t\t\t\t\t\t\t\t\t\t\t<div class=\"elementor-gallery-item__overlay\"><\/div>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/a>\n\t\t\t\t\t\t\t<a class=\"e-gallery-item elementor-gallery-item elementor-animated-content\" href=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/debris_avalanche.jpg\" data-elementor-open-lightbox=\"yes\" data-elementor-lightbox-slideshow=\"all-c81d011\" data-elementor-lightbox-title=\"debris_avalanche\" data-e-action-hash=\"#elementor-action%3Aaction%3Dlightbox%26settings%3DeyJpZCI6MTk0MiwidXJsIjoiaHR0cHM6XC9cL2Jlc2FmZW5ldC5uZXRcL3dwLWNvbnRlbnRcL3VwbG9hZHNcLzIwMjBcLzExXC9kZWJyaXNfYXZhbGFuY2hlLmpwZyIsInNsaWRlc2hvdyI6ImFsbC1jODFkMDExIn0%3D\">\n\t\t\t\t\t<div class=\"e-gallery-image elementor-gallery-item__image\" data-thumbnail=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/debris_avalanche.jpg\" data-width=\"568\" data-height=\"331\" aria-label=\"\" role=\"img\" ><\/div>\n\t\t\t\t\t\t\t\t\t\t\t<div class=\"elementor-gallery-item__overlay\"><\/div>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-a18f045 elementor-widget elementor-widget-text-editor\" data-id=\"a18f045\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Debris flow is a very rapid to extremely rapid flow (&gt; 1 m.s-1) of saturated non-plastic debris in a steep channel. The key characteristic of a debris flow is the presence of an established channel or regular confined path, unlike debris avalanches which are thin, partly or totally saturated, and which occur on hillslopes. Debris flows and debris avalanches are complex movements. They consist of a mixture of coarse material (gravel and boulders) embedded in a sandy-silty matrix, with a variable quantity of water (Costa and Wieczorek, 1987; Iverson et al., 1997). In spite of varying velocities and total solid fractions debris flows and debris avalanches show many similarities, particularly in the way they are triggered. Debris flows and debris avalanches are commonly triggered by an excess of water: intense rainfall, rapid snowmelt, and more rarely, glacier or lake overflows which mobilize unconsolidated material in their path. Rainfall intensity and duration, along with antecedent rainfall conditions, are strong controls for debris flow triggering (Dikau et al., 1996).<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-1c771c0 elementor-widget elementor-widget-gallery\" data-id=\"1c771c0\" data-element_type=\"widget\" data-settings=\"{&quot;gallery_layout&quot;:&quot;justified&quot;,&quot;ideal_row_height&quot;:{&quot;unit&quot;:&quot;px&quot;,&quot;size&quot;:500,&quot;sizes&quot;:[]},&quot;overlay_description&quot;:&quot;caption&quot;,&quot;lazyload&quot;:&quot;yes&quot;,&quot;ideal_row_height_tablet&quot;:{&quot;unit&quot;:&quot;px&quot;,&quot;size&quot;:150,&quot;sizes&quot;:[]},&quot;ideal_row_height_mobile&quot;:{&quot;unit&quot;:&quot;px&quot;,&quot;size&quot;:150,&quot;sizes&quot;:[]},&quot;gap&quot;:{&quot;unit&quot;:&quot;px&quot;,&quot;size&quot;:10,&quot;sizes&quot;:[]},&quot;gap_tablet&quot;:{&quot;unit&quot;:&quot;px&quot;,&quot;size&quot;:10,&quot;sizes&quot;:[]},&quot;gap_mobile&quot;:{&quot;unit&quot;:&quot;px&quot;,&quot;size&quot;:10,&quot;sizes&quot;:[]},&quot;link_to&quot;:&quot;file&quot;,&quot;overlay_background&quot;:&quot;yes&quot;,&quot;content_hover_animation&quot;:&quot;fade-in&quot;}\" data-widget_type=\"gallery.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<div class=\"elementor-gallery__container\">\n\t\t\t\t\t\t\t<a class=\"e-gallery-item elementor-gallery-item elementor-animated-content\" href=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_1_2_53.jpg\" data-elementor-open-lightbox=\"yes\" data-elementor-lightbox-slideshow=\"all-1c771c0\" data-elementor-lightbox-title=\"2_1_2_53\" data-e-action-hash=\"#elementor-action%3Aaction%3Dlightbox%26settings%3DeyJpZCI6MjEyNCwidXJsIjoiaHR0cHM6XC9cL2Jlc2FmZW5ldC5uZXRcL3dwLWNvbnRlbnRcL3VwbG9hZHNcLzIwMjBcLzExXC8yXzFfMl81My5qcGciLCJzbGlkZXNob3ciOiJhbGwtMWM3NzFjMCJ9\">\n\t\t\t\t\t<div class=\"e-gallery-image elementor-gallery-item__image\" data-thumbnail=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_1_2_53.jpg\" data-width=\"289\" data-height=\"432\" aria-label=\"\" role=\"img\" ><\/div>\n\t\t\t\t\t\t\t\t\t\t\t<div class=\"elementor-gallery-item__overlay\"><\/div>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<div class=\"elementor-gallery-item__content\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<div class=\"elementor-gallery-item__description\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\tFig. 1: Debris flow catchment showing all the main features, Genestaza valley Asturias, Spain (from Dikau et al., 1996)\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t\t<\/a>\n\t\t\t\t\t\t\t<a class=\"e-gallery-item elementor-gallery-item elementor-animated-content\" href=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_1_2_54.jpg\" data-elementor-open-lightbox=\"yes\" data-elementor-lightbox-slideshow=\"all-1c771c0\" data-elementor-lightbox-title=\"2_1_2_54\" data-e-action-hash=\"#elementor-action%3Aaction%3Dlightbox%26settings%3DeyJpZCI6MjExOSwidXJsIjoiaHR0cHM6XC9cL2Jlc2FmZW5ldC5uZXRcL3dwLWNvbnRlbnRcL3VwbG9hZHNcLzIwMjBcLzExXC8yXzFfMl81NC5qcGciLCJzbGlkZXNob3ciOiJhbGwtMWM3NzFjMCJ9\">\n\t\t\t\t\t<div class=\"e-gallery-image elementor-gallery-item__image\" data-thumbnail=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_1_2_54.jpg\" data-width=\"345\" data-height=\"430\" aria-label=\"\" role=\"img\" ><\/div>\n\t\t\t\t\t\t\t\t\t\t\t<div class=\"elementor-gallery-item__overlay\"><\/div>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<div class=\"elementor-gallery-item__content\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<div class=\"elementor-gallery-item__description\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\tsource area and flow track at Tures valley, E italian Alps (Photo by D. Piacentini)\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t\t<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-8645b63 elementor-widget elementor-widget-image\" data-id=\"8645b63\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"378\" height=\"256\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_1_2_55.jpg\" class=\"attachment-large size-large wp-image-2132\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_1_2_55.jpg 378w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_1_2_55-300x203.jpg 300w\" sizes=\"(max-width: 378px) 100vw, 378px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 2: Source area of Cancia debris flow, Dolomites, E Alps, Italy (photo by A. Pasuto)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-3f9f6ab elementor-widget elementor-widget-gallery\" data-id=\"3f9f6ab\" data-element_type=\"widget\" data-settings=\"{&quot;gallery_layout&quot;:&quot;justified&quot;,&quot;ideal_row_height&quot;:{&quot;unit&quot;:&quot;px&quot;,&quot;size&quot;:290,&quot;sizes&quot;:[]},&quot;overlay_description&quot;:&quot;caption&quot;,&quot;lazyload&quot;:&quot;yes&quot;,&quot;ideal_row_height_tablet&quot;:{&quot;unit&quot;:&quot;px&quot;,&quot;size&quot;:150,&quot;sizes&quot;:[]},&quot;ideal_row_height_mobile&quot;:{&quot;unit&quot;:&quot;px&quot;,&quot;size&quot;:150,&quot;sizes&quot;:[]},&quot;gap&quot;:{&quot;unit&quot;:&quot;px&quot;,&quot;size&quot;:10,&quot;sizes&quot;:[]},&quot;gap_tablet&quot;:{&quot;unit&quot;:&quot;px&quot;,&quot;size&quot;:10,&quot;sizes&quot;:[]},&quot;gap_mobile&quot;:{&quot;unit&quot;:&quot;px&quot;,&quot;size&quot;:10,&quot;sizes&quot;:[]},&quot;link_to&quot;:&quot;file&quot;,&quot;overlay_background&quot;:&quot;yes&quot;,&quot;content_hover_animation&quot;:&quot;fade-in&quot;}\" data-widget_type=\"gallery.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<div class=\"elementor-gallery__container\">\n\t\t\t\t\t\t\t<a class=\"e-gallery-item elementor-gallery-item elementor-animated-content\" href=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_1_2_56.jpg\" data-elementor-open-lightbox=\"yes\" data-elementor-lightbox-slideshow=\"all-3f9f6ab\" data-elementor-lightbox-title=\"2_1_2_56\" data-e-action-hash=\"#elementor-action%3Aaction%3Dlightbox%26settings%3DeyJpZCI6MjE0MywidXJsIjoiaHR0cHM6XC9cL2Jlc2FmZW5ldC5uZXRcL3dwLWNvbnRlbnRcL3VwbG9hZHNcLzIwMjBcLzExXC8yXzFfMl81Ni5qcGciLCJzbGlkZXNob3ciOiJhbGwtM2Y5ZjZhYiJ9\">\n\t\t\t\t\t<div class=\"e-gallery-image elementor-gallery-item__image\" data-thumbnail=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_1_2_56.jpg\" data-width=\"366\" data-height=\"239\" aria-label=\"\" role=\"img\" ><\/div>\n\t\t\t\t\t\t\t\t\t\t\t<div class=\"elementor-gallery-item__overlay\"><\/div>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<div class=\"elementor-gallery-item__content\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<div class=\"elementor-gallery-item__description\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\tFig. 3: Deposit area of debris flow at S. Vigilio di Marebbe , Dolomites, E Alps, Italy (photo by M. Marchetti) \t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t\t<\/a>\n\t\t\t\t\t\t\t<a class=\"e-gallery-item elementor-gallery-item elementor-animated-content\" href=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_1_2_57.jpg\" data-elementor-open-lightbox=\"yes\" data-elementor-lightbox-slideshow=\"all-3f9f6ab\" data-elementor-lightbox-title=\"2_1_2_57\" data-e-action-hash=\"#elementor-action%3Aaction%3Dlightbox%26settings%3DeyJpZCI6MjEzOCwidXJsIjoiaHR0cHM6XC9cL2Jlc2FmZW5ldC5uZXRcL3dwLWNvbnRlbnRcL3VwbG9hZHNcLzIwMjBcLzExXC8yXzFfMl81Ny5qcGciLCJzbGlkZXNob3ciOiJhbGwtM2Y5ZjZhYiJ9\">\n\t\t\t\t\t<div class=\"e-gallery-image elementor-gallery-item__image\" data-thumbnail=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_1_2_57.jpg\" data-width=\"324\" data-height=\"242\" aria-label=\"\" role=\"img\" ><\/div>\n\t\t\t\t\t\t\t\t\t\t\t<div class=\"elementor-gallery-item__overlay\"><\/div>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<div class=\"elementor-gallery-item__content\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<div class=\"elementor-gallery-item__description\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\tLe Chatelaret, Alps, France (photo by M. Soldati)\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t\t<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-2a46590 elementor-widget elementor-widget-image\" data-id=\"2a46590\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"305\" height=\"229\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_1_2_58.jpg\" class=\"attachment-large size-large wp-image-2152\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_1_2_58.jpg 305w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_1_2_58-300x225.jpg 300w\" sizes=\"(max-width: 305px) 100vw, 305px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 4: Debris flows in the Tagliole Valley, Northern Apennines, Italy (photo by D. Castaldini)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-7900d1c elementor-widget elementor-widget-image\" data-id=\"7900d1c\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"198\" height=\"294\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_1_2_59.jpg\" class=\"attachment-large size-large wp-image-2157\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 5: Debris flow occurred at TsingShan (Photo by Hungr)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-6bea3a7 elementor-widget elementor-widget-text-editor\" data-id=\"6bea3a7\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><strong>Mudflow (soil flow)<\/strong><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-e1d861e elementor-widget elementor-widget-image\" data-id=\"e1d861e\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"466\" height=\"281\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Picture14.gif\" class=\"attachment-large size-large wp-image-1947\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Small mudflow (from Dikau et al., 1996)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-7bd94d6 elementor-widget elementor-widget-text-editor\" data-id=\"7bd94d6\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Mudflows (or Soil flows) are similar in form and behaviour to debris flows. They can be very slow to very mobile and can flow downslope quite quickly. They tend to follow gullies or shallow depressions to spread out into a flat, bulbous fan or even a thin sheet.<\/p><p><strong>References:<\/strong><\/p><p>For the references herein and for knowing sources of didactic material go to 1.3 Selected references<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-9813\" class=\"elementor-tab-title\" data-tab=\"3\" role=\"tab\" aria-controls=\"elementor-tab-content-9813\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">2.1.3 More details on lateral spreading<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-9813\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"3\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-9813\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"2165\" class=\"elementor elementor-2165\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-0bb1ab2 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"0bb1ab2\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-8fac0ce\" data-id=\"8fac0ce\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-b4a7884 elementor-widget elementor-widget-text-editor\" data-id=\"b4a7884\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><strong>What is a lateral spreading phenomenon?<\/strong><br \/>(Extract from Maquaire and Malet, 2006)<\/p><p>Lateral spreading are lateral displacements situated at a certain depth and resting on stable formations. When they occur in coherent rock, whether or not resting on clay deposits or on plastic marl, they may affect a rock massif over considerable thicknesses and are therefore considered as deep-seated landslides. For further information the reader should refer to the following: Jahn, 1964; Bentley and Smalley, 1984.<\/p><p><strong>Soil (debris) lateral spreading<\/strong><br \/>(from Maquaire and Malet, 2006)<\/p><p>We will confine our discussion to shallow lateral spreading occurring in non-cohesive heterogeneous materials such as moraine deposits (debris spreading) or fine clay or sand formations (soil spreading). Fine formations particularly sensitive to this type of movement include varved clays deposited on the banks of the great Pleistocene glaciers in Scandinavia or over smaller areas in the old pro-glacier lakes of the Swiss Alpine border or in the Alpine valleys (Tri\u00e8ves in France; Nieuwenhuis, 1991). Their sensitivity is due to their very low plasticity. Sands may easily liquefy and give rise to this type of movement. Lateral spreading may also develop in coarse and heterogeneous moraine formations (Noverraz et al., 2001).<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-975676a elementor-widget elementor-widget-image\" data-id=\"975676a\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"626\" height=\"233\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/lattering_spreading_01.jpg\" class=\"attachment-large size-large wp-image-2168\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/lattering_spreading_01.jpg 626w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/lattering_spreading_01-300x112.jpg 300w\" sizes=\"(max-width: 626px) 100vw, 626px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Block diagram of soil lateral spreading failure in fine sand and silt seams (from Dikau et al., 1996 adapted from Varnes, 1978)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-54f5ade elementor-widget elementor-widget-text-editor\" data-id=\"54f5ade\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>These movements may occur on very gentle slopes of 5\u00b0 or less. They display a characteristic morphology (Figure): upstream at the source, a scarp with multiple lobes dominates the displaced part where horsts or rift valleys appear; downstream these shapes are elongated by perpendicular folds in the direction of the movement. The space affected by these movements is often as wide as it is long and they often occur over a very short period of time.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-ab3563b elementor-widget elementor-widget-image\" data-id=\"ab3563b\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"512\" height=\"342\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/lattering_spreading_02.jpg\" class=\"attachment-large size-large wp-image-2174\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/lattering_spreading_02.jpg 512w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/lattering_spreading_02-300x200.jpg 300w\" sizes=\"(max-width: 512px) 100vw, 512px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Soil spreading near Namdaelen, Norway (from Dikau et al., 1996)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-3abd6c7 elementor-widget elementor-widget-text-editor\" data-id=\"3abd6c7\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><strong>Rock lateral spreading<\/strong><br \/>(From Dikau et al., 1996)<\/p><p>Rock spreading consists of lateral extensions of rock masses either in homogeneous rock or in cohesive rock overlying ductile materials. The latter occur along shears with tensile fractures occurring on overlying coherent rock. Though often decribed as part of complex slope movements, in certain geological conditions they give rise to such peculiar morphological features that they are considered as a separate type of movement.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-1604b48 elementor-widget elementor-widget-image\" data-id=\"1604b48\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"362\" height=\"212\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/lattering_spreading_03.jpg\" class=\"attachment-large size-large wp-image-2180\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/lattering_spreading_03.jpg 362w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/lattering_spreading_03-300x176.jpg 300w\" sizes=\"(max-width: 362px) 100vw, 362px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-e6fbfb7 elementor-widget elementor-widget-image\" data-id=\"e6fbfb7\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"475\" height=\"216\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/lattering_spreading_04.jpg\" class=\"attachment-large size-large wp-image-2185\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/lattering_spreading_04.jpg 475w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/lattering_spreading_04-300x136.jpg 300w\" sizes=\"(max-width: 475px) 100vw, 475px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-289b40e figure-caption elementor-widget elementor-widget-text-editor\" data-id=\"289b40e\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p style=\"text-align: center;\"><em>Schematic block diagram showing lateral spreading in homogeneous (a) and non-homogeneous (b) rocks (from Dikau et al. 1996)<\/em><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-811f97f elementor-widget elementor-widget-image\" data-id=\"811f97f\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"292\" height=\"219\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/lattering_spreading_05.jpg\" class=\"attachment-large size-large wp-image-2191\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Rock spreading and \u201ccollateral movements\u201d at Cinque Torri, Cortina d\u2019Ampezzo, Dolomites, E Alps, Italy (photo by M. Soldati)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-68cb91d elementor-widget elementor-widget-image\" data-id=\"68cb91d\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"294\" height=\"219\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/lattering_spreading_06.jpg\" class=\"attachment-large size-large wp-image-2197\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Rock spreading at Mt. Cimone area, Northern Apennines, Italy (Photo by D. Castaldini)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-ff7e392 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"ff7e392\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-50 elementor-top-column elementor-element elementor-element-c073b2c\" data-id=\"c073b2c\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-840ad39 elementor-widget elementor-widget-image\" data-id=\"840ad39\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"407\" height=\"270\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/lattering_spreading_07.jpg\" class=\"attachment-large size-large wp-image-2207\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/lattering_spreading_07.jpg 407w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/lattering_spreading_07-300x199.jpg 300w\" sizes=\"(max-width: 407px) 100vw, 407px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-50 elementor-top-column elementor-element elementor-element-7c29885\" data-id=\"7c29885\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-e174781 elementor-widget elementor-widget-image\" data-id=\"e174781\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"401\" height=\"267\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/lattering_spreading_08.jpg\" class=\"attachment-large size-large wp-image-2202\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/lattering_spreading_08.jpg 401w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/lattering_spreading_08-300x200.jpg 300w\" sizes=\"(max-width: 401px) 100vw, 401px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-ff68fa1 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"ff68fa1\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-b5c9096\" data-id=\"b5c9096\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-29c213b figure-caption elementor-widget elementor-widget-text-editor\" data-id=\"29c213b\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p style=\"text-align: center;\"><em>Lateral spreading at Simoncello and Sasso di Simone, northern Apennines, Italy. In the right photos a detail of cracks and trenches on the Sasso di Simone. (from Dikau et al. 1996<\/em><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-4f3c245 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"4f3c245\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-50 elementor-top-column elementor-element elementor-element-5c64a52\" data-id=\"5c64a52\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-1d51661 elementor-widget elementor-widget-image\" data-id=\"1d51661\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"322\" height=\"240\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/lattering_spreading_09.jpg\" class=\"attachment-large size-large wp-image-2219\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/lattering_spreading_09.jpg 322w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/lattering_spreading_09-300x224.jpg 300w\" sizes=\"(max-width: 322px) 100vw, 322px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-50 elementor-top-column elementor-element elementor-element-e3aae14\" data-id=\"e3aae14\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-7c870f0 elementor-widget elementor-widget-image\" data-id=\"7c870f0\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"325\" height=\"244\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/lattering_spreading_10.jpg\" class=\"attachment-large size-large wp-image-2214\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/lattering_spreading_10.jpg 325w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/lattering_spreading_10-300x225.jpg 300w\" sizes=\"(max-width: 325px) 100vw, 325px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-d518971 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"d518971\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-4c8010e\" data-id=\"4c8010e\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-82a5884 figure-caption elementor-widget elementor-widget-text-editor\" data-id=\"82a5884\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p style=\"text-align: center;\"><em>Panoramic view (left) and trench details of the lateral spreading at Popeye Village, NW coast of Malta: (photos by M. Soldati)<\/em><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-3f492ce elementor-widget elementor-widget-text-editor\" data-id=\"3f492ce\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><strong>References:<\/strong><\/p><p>BENTLEY SP, SMALLEY IJ.. 1984. Landslips in sensitive clays. In Slope Instability, BRUNSDEN D, PRIOR DB. (eds.). Wiley: Chichester; 457-490.<\/p><p>JAHN A. 1964. Slope morphological features resulting from gravitation. Zeitschrift f\u00fcr Geomorphologie, Supplement Band 5: 59-72.<\/p><p>NIEUWENHUIS JD. 1991. Variations in the stability and displacements of a shallow seasonal landslide in varved clays. Balkema: Rotterdam.<\/p><p>NOVERRAZ F., BONNARD C, DUPRAZ H, HUGUENIN L. 2001. Versinclim: comportement pass\u00e9, pr\u00e9sent et futur des grands versants instables en fonction de l\u2019\u00e9volution climatique. Hochschulverlag AG: Z\u00fcrich.<\/p><p>For the other references herein and for knowing sources of didactic material go to 1.3 Selected references.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-9814\" class=\"elementor-tab-title\" data-tab=\"4\" role=\"tab\" aria-controls=\"elementor-tab-content-9814\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">2.1.4 More information on landslides classification <\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-9814\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"4\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-9814\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"2227\" class=\"elementor elementor-2227\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-c60711e elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"c60711e\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-6879d05\" data-id=\"6879d05\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-cd295b2 elementor-widget elementor-widget-text-editor\" data-id=\"cd295b2\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>By Alessandro Pasuto1, Mauro Soldati2, &amp; Doriano Castaldini<br \/>21 CNR &#8211; IRPI Padova (Italy)<br \/>2 Dipartimento di Scienze della Terra, Universit\u00e0 di Modena e Reggio Emilia (Italy)<\/p><p>When a study of mass movements is enterprised, which also aims to define landslide hazard, it is of paramount importance to use clear terminology which can be universally understood also by non-specialists (IAEG, 1990). It is therefore important for these phenomena to be immediately identified and subdivided according to the characteristics directly observable. In scientific literature, there are several \u00ab\u00a0classifications\u00a0\u00bb regarding to slope movements which have been proposed since the beginning of the 20th century. These often complied with the needs of various authors but more recently an effort has been made to use the least ambiguous terminology.<\/p><p>Most recent classifications try to emphasize both the processes leading to the development of a landslide and the materials involved; others are based on morphology, landslide mechanism, deformation velocity, causes of movement, geometry of the failure area and the deposits, age, etc. This section does not aim to describe the numerous \u00ab\u00a0classifications\u00a0\u00bb proposed but particular attention will be given to the most commonly accepted, that is illustrated and subsequently modified by Varnes (Varnes, 1978; Cruden &amp; Varnes, 1996) Varnes proposed his first subdivision in 1958; subsequent elaborations were carried out in 1978 and 1996 and at the moment this subdivision is universally accepted.<\/p><p>The main criterion used by the author in the identification of the landslide categories is the type of movement, whereas a further subdivision is made on the basis of the type of material. As for the type of movement, five categories are represented: falls, topples, slides, spreads and flows. On the other hand, the materials are divided into two types: rock and engineering soil; the latter is further subdivided into debris and earth. In this way a landslide can be described by means of two words: the first one describing the material and the second one the type of movement (Table 1).<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-8ba721e elementor-widget elementor-widget-image\" data-id=\"8ba721e\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"865\" height=\"227\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/more_on_classifications_1.jpg\" class=\"attachment-large size-large wp-image-2230\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/more_on_classifications_1.jpg 865w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/more_on_classifications_1-300x79.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/more_on_classifications_1-768x202.jpg 768w\" sizes=\"(max-width: 865px) 100vw, 865px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Table 1. Abbreviated classification of Slope Movements (from Cruden &amp; Varnes, 1996)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-38f2d8e elementor-widget elementor-widget-text-editor\" data-id=\"38f2d8e\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Complex: is the result of the combination of two or more of the five classes above illustrated. In the Cruden &amp; Varnes (1996) classification the term \u00abcomplex\u00bb has been retained as a description of the style of activity of a landslide. Moreover, other attributes are introduced so that the definition becomes more elaborate but more information is thus available on the gravitational movement. The type of landslide is described by a series of adjectives placed in sequence which provide information about the activity, the rate of movement, the moisture content, the material and type of movement (e.g. active rapid wet rock slide).<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-a3c580f elementor-widget elementor-widget-image\" data-id=\"a3c580f\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"426\" height=\"317\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/more_on_classifications_2.jpg\" class=\"attachment-large size-large wp-image-2235\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/more_on_classifications_2.jpg 426w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/more_on_classifications_2-300x223.jpg 300w\" sizes=\"(max-width: 426px) 100vw, 426px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Gaiato active complex landslide, Northern Apennines, Italy: rock fall in the upper part, earth flow in the mid-lower part of the slope (photo D. Castaldini).<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-e5b7865 elementor-widget elementor-widget-text-editor\" data-id=\"e5b7865\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<div class=\"tdFaqCond row\"><p>For the references herein and for knowing sources of didactic material go to 1.3 Selected references.<\/p><\/div>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p>\n<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-2083\" class=\"elementor-tab-title\" data-tab=\"3\" role=\"tab\" aria-controls=\"elementor-tab-content-2083\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">3. Comment s\u2019expliquent les glissements de terrain ?<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-2083\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"3\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-2083\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"7923\" class=\"elementor elementor-7923 elementor-2241\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-89c20c3 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"89c20c3\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-49ceb8b\" data-id=\"49ceb8b\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-02cee40 elementor-widget elementor-widget-text-editor\" data-id=\"02cee40\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Les glissements de terrain sont la manifestation de masses de terrain d\u00e9stabilis\u00e9es sous l\u2019effet de\u00a0:<\/p>\n<ul>\n<li><strong>pr\u00e9dispositions\u00a0:<\/strong>\n<ul>\n<li><u>morphologiques<\/u>\u00a0: g\u00e9om\u00e9trie de la pente (hauteur, longueur, forme, d\u00e9clivit\u00e9, aspect, etc.),<\/li>\n<li><u>g\u00e9ologiques<\/u>\u00a0:\u00a0composition du sol ou lithologie (argile, calcaire, mat\u00e9riau meuble, \u00e9rod\u00e9, etc.), structure et discontinuit\u00e9s (stratification, schistosit\u00e9, foliation, failles, fractures, etc.),<\/li>\n<li><u>v\u00e9g\u00e9tales<\/u>\u00a0:\u00a0couvert forestier, prairies naturelles, p\u00e2turages, terres arables, cultures permanentes, roches nues, etc.<\/li>\n<\/ul>\n<\/li>\n<li><strong>facteurs d\u00e9clenchants\u00a0:<\/strong>\n<ul>\n<li><u>causes physiques<\/u>\u00a0:\u00a0s\u00e9ismes, \u00e9ruptions volcaniques, conditions climatiques (pluies abondantes, fonte des neiges, alternance gel\/d\u00e9gel, etc.),<\/li>\n<li><u>causes g\u00e9omorphologiques<\/u>\u00a0: \u00e9rosion de berges ou du littoral au pied d\u2019une pente, d\u00e9p\u00f4t, surcharge, etc.<\/li>\n<li><u>causes anthropiques<\/u>\u00a0:\u00a0terrassement, vibration, d\u00e9forestation, exploitation de mat\u00e9riaux ou de la nappe phr\u00e9atique, excavation, construction routi\u00e8re, exploitation mini\u00e8re, carri\u00e8re, travaux de chargement, etc.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p>Les causes de glissements de terrain, g\u00e9n\u00e9ralement multiples, se manifestent sous forme d\u2019une combinaison ou d\u2019une superposition de diff\u00e9rents facteurs.<\/p>\n<p>On divise g\u00e9n\u00e9ralement ces causes en deux cat\u00e9gories\u00a0:<\/p>\n<ul>\n<li><strong>causes internes<\/strong>,\u00a0li\u00e9es aux forces de r\u00e9sistance.\n<ul>\n<li>Ces causes conduisent \u00e0 l\u2019affaissement de la pente sans intervention de changements manifestes \u00e0 la surface\u00a0; il s\u2019agit de facteurs qui affaiblissent la r\u00e9sistance du terrain au cisaillement. Les causes internes \u00e0 l\u2019origine de l\u2019instabilit\u00e9 d\u2019une pente sont sa morphologie, sa g\u00e9ologie et les conditions climatiques.<\/li>\n<\/ul>\n<\/li>\n<li><strong>causes externes<\/strong>, li\u00e9es aux forces motrices (gravit\u00e9, infiltrations d\u2019eau, pression par exemple).\n<ul>\n<li>Ces causes contribuent \u00e0 augmenter les contraintes de cisaillement au moyen de modifications plus ou moins manifestes de la morphologie de la pente. Parmi les plus importantes figurent les suivantes\u00a0: sapement d\u00fb \u00e0 l\u2019\u00e9rosion d\u2019un cours d\u2019eau ou \u00e0 des travaux d\u2019excavation pour la construction d\u2019une route, exploitation de carri\u00e8res ou de mines \u00e0 ciel ouvert, surcharge, suppression de supports lat\u00e9raux, pression lat\u00e9rale, activit\u00e9 tectonique, effet de la v\u00e9g\u00e9tation.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p>Une pente est stable lorsque les forces de r\u00e9sistance sont sup\u00e9rieures ou \u00e9gales aux forces motrices (ou d\u00e9stabilisatrices). Le ratio entre les forces de r\u00e9sistance et les forces motrices est appel\u00e9 facteur de s\u00e9curit\u00e9. On l\u2019utilise habituellement comme mesure de la stabilit\u00e9 d\u2019une pente.<\/p>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-9cc2664 elementor-widget elementor-widget-image\" data-id=\"9cc2664\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"766\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/DSCN4491AndS_PhAbove-1024x766.jpg\" class=\"attachment-large size-large wp-image-2252\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/DSCN4491AndS_PhAbove-1024x766.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/DSCN4491AndS_PhAbove-300x224.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/DSCN4491AndS_PhAbove-768x575.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/DSCN4491AndS_PhAbove-1536x1149.jpg 1536w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/DSCN4491AndS_PhAbove-2048x1532.jpg 2048w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-011e36a elementor-widget elementor-widget-image\" data-id=\"011e36a\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"766\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/DSCN4523PhBelow-1024x766.jpg\" class=\"attachment-large size-large wp-image-2257\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/DSCN4523PhBelow-1024x766.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/DSCN4523PhBelow-300x224.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/DSCN4523PhBelow-768x575.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/DSCN4523PhBelow-1536x1149.jpg 1536w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/DSCN4523PhBelow-2048x1532.jpg 2048w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-268948c figure-caption elementor-widget elementor-widget-text-editor\" data-id=\"268948c\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><em>Sol\u00e0, Andorre-La-Vieille (Andorre)<br \/>\nLe 20 avril 2008, un pan rocheux se d\u00e9tache d\u2019une falaise suite \u00e0 des pluies abondantes et explose en une centaine de blocs. Les deux plus gros fragments franchissent les \u00e9crans pare-bloc au pied de la pente. L\u2019un finira sa course dans un entrep\u00f4t.<br \/>\n(cr\u00e9dit photo\u00a0: D. Castaldini, septembre 2008)<\/em><\/p>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-ed672d0 elementor-widget elementor-widget-image\" data-id=\"ed672d0\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"768\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/franaMaieratonew-1024x768.png\" class=\"attachment-large size-large wp-image-2247\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/franaMaieratonew-1024x768.png 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/franaMaieratonew-300x225.png 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/franaMaieratonew-768x576.png 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/franaMaieratonew-1536x1152.png 1536w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/franaMaieratonew-2048x1536.png 2048w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-cc75289 figure-caption elementor-widget elementor-widget-text-editor\" data-id=\"cc75289\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><em>(photo http:\/\/www.ansa.it\/)<br \/>\nFig. 1. Glissement de terrain survenu le 15 f\u00e9vrier 2010 \u00e0 proximit\u00e9 de la ville italienne de Maierato (Calabre) \u00e0 la suite de fortes pluies. Aucun d\u00e9c\u00e8s ni blessure ne fut \u00e0 d\u00e9plorer, mais environ 2\u00a0300 habitants de la ville durent \u00e9vacuer la zone lorsqu\u2019un flanc de la colline c\u00e9da, ensevelissant leurs maisons sous des tonnes de terre, de roche et de d\u00e9bris. Malgr\u00e9 l\u2019absence de victimes, les \u00e9quipes d\u2019intervention envoy\u00e9es sur place d\u00e9crivirent un spectacle \u00ab\u00a0apocalyptique\u00a0\u00bb de d\u00e9vastation et compar\u00e8rent Maierato \u00e0 une \u00ab\u00a0ville fant\u00f4me\u00a0\u00bb. Une vid\u00e9o du glissement de terrain montre la colline en train de s\u2019affaisser lentement (http:\/\/daveslandslideblog.blogspot.com\/2010\/02\/watch-this-extraordinary-landslide.html)<\/em><\/p>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-ecdf9b7 elementor-widget elementor-widget-accordion\" data-id=\"ecdf9b7\" data-element_type=\"widget\" data-widget_type=\"accordion.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<div class=\"elementor-accordion\" role=\"tablist\">\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-2481\" class=\"elementor-tab-title\" data-tab=\"1\" role=\"tab\" aria-controls=\"elementor-tab-content-2481\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">3.1. More informations on Factors and Causes<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-2481\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"1\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-2481\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"2264\" class=\"elementor elementor-2264\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-0948993 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"0948993\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-5c6f503\" data-id=\"5c6f503\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-d43a040 elementor-widget elementor-widget-text-editor\" data-id=\"d43a040\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Landslides are associated with a displacement of masses of destabilized earth due to:<\/p><ul><li><strong>Conditioning factors<\/strong><ul><li>Morphological features: slope geometry (i.e., its height, length, shape, slope angle and aspect),<\/li><li>Geological factors: nature of the soil parent materials or lithology (i.e. clay, limestone, weak material, weathered material etc.) and structure and discontinuities (bedding planes, schistosity and foliation planes, faults, fractures etc.), Landcover: forest, natural grasslands, pastures, arable lands, permanent crops, bare rocks, etc.<\/li><\/ul><\/li><li><strong>Triggering factors:<\/strong><ul><li><strong>\u200b<\/strong>Physical processes: earthquakes, volcanic eruptions, climatic conditions (abnormally heavy rainfalls, snow melt, freeze and thaw etc.),<\/li><li>Geomorphologic processes: fluvial or wave erosion at the toe of the slope, deposition, loading etc.<\/li><li>Man-made processes: terracing, vibration, deforestation, the exploitation of materials or water tables, excavation, road construction, mining and quarrying, loading etc.<\/li><\/ul><\/li><\/ul><p>The causes of landslides are thus generally multiple, a conjunction or superimposition of several factors.<\/p><p>Causes are also often divided into two large categories:<\/p><ul><li><strong>Internal causes,<\/strong>\u00a0which are related to resisting forces.<ul><li>They lead to the failure of the slope without the intervention of perceptible changes on the surface; they are in fact causes which reduce the material&rsquo;s shear strength. The internal causes which condition the instability of a slope are geological factors, morphological features and climatic conditions.<\/li><\/ul><\/li><li><strong>External causes,\u00a0<\/strong>which are related to driving forces (e.g. gravity, water through flow, pressure).<ul><li>They determine an increase of the shear stresses by means of more or less evident modifications of slope morphology. Among these processes the following are particularly important: Undercutting due to the erosion of a watercourse or to the excavation for road construction, exploitation of quarries or open pits, overloading, removal of lateral support, lateral pressure, tectonic activity, effect of vegetation.<\/li><\/ul><\/li><\/ul><p>A slope is stable when the resisting forces are superior or equal to the driving forces (or destabilising forces). The ratio between resisting forces and driving forces is the safety Factor. It is conventionally taken as the measure for the stability of a slope.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-695157e elementor-widget elementor-widget-image\" data-id=\"695157e\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"768\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/franaMaieratonew-1024x768.png\" class=\"attachment-large size-large wp-image-2247\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/franaMaieratonew-1024x768.png 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/franaMaieratonew-300x225.png 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/franaMaieratonew-768x576.png 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/franaMaieratonew-1536x1152.png 1536w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/franaMaieratonew-2048x1536.png 2048w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-b30ab08 figure-caption elementor-widget elementor-widget-text-editor\" data-id=\"b30ab08\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p style=\"text-align: center;\"><em>(photo by http:\/\/www.ansa.it\/)\u00a0<br \/>Fig. 1. The landslide near the southern Italian town of Maierato (Calabria region) which occurred on 15th february 2010 caused by heavy rains. No deaths or injuries have been reported, but about 2300 residents of the town were forced to evacuate when a section of hillside broke off burying their homes under rubble and debris. Though there were no injuries or deaths, relief workers on the scene described \u00a0\u00bbapocalyptic\u00a0\u00bb devastation and said that Maierato had been reduced to a \u00a0\u00bbghost town\u00a0\u00bb. A video of the landslide shows the hillside slowly moving forward (e.g. see video at: http:\/\/daveslandslideblog.blogspot.com\/2010\/02\/watch-this-extraordinary-landslide.html)<\/em><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-872a5de elementor-widget elementor-widget-accordion\" data-id=\"872a5de\" data-element_type=\"widget\" data-widget_type=\"accordion.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<div class=\"elementor-accordion\" role=\"tablist\">\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-1411\" class=\"elementor-tab-title\" data-tab=\"1\" role=\"tab\" aria-controls=\"elementor-tab-content-1411\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">3.1.1 More details on the role of water<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-1411\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"1\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-1411\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"2268\" class=\"elementor elementor-2268\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-9d88c5d elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"9d88c5d\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-70b3f72\" data-id=\"70b3f72\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-b6bbdf8 elementor-widget elementor-widget-text-editor\" data-id=\"b6bbdf8\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>The role of water is significant but very varied. In the first instance it acts on the state or consistency of materials, for example, for clay and for an increase in water holding capacity, passage from a solid to a plastic and then to a liquid state. Secondly, the water transports material. Finally and most important, it acts on the underground water by means of the Archimedes thrust (Terzaghi\u2019s law) which lifts or lightens the soil (Terzaghi, 1950). In the soil, the \u201cArchimede thrust\u201d is characterized by a decrease of effective normal stress (transmitted by the solid soil skeleton). The soil is lightened and the bulk unit weight is like: g &#8211; gw = g\u2019<\/p><p>The consequence for the slopes is a decrease in the friction forces along the surfaces of the rupture, which promotes movement. Everyone can observe this phenomenon in the bath or in the swimming pool!<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-56cc6de elementor-widget elementor-widget-image\" data-id=\"56cc6de\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"286\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/meca41-1024x286.gif\" class=\"attachment-large size-large wp-image-2272\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/meca41-1024x286.gif 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/meca41-300x84.gif 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/meca41-768x215.gif 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/meca41-1536x429.gif 1536w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-2b0f2ef elementor-widget elementor-widget-text-editor\" data-id=\"2b0f2ef\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Effective normal stress (s\u2019) Due to the decrease of the effective normal stress at the surface of the bathroom with the body, the man could easily move and fall down in the water!! The role of water may be appreciated by studying previous climatic conditions, both close and distant, which will contribute to feeding the water table (see case study: Villerville-Cricqueboeuf landslide IS MISSING).<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-1412\" class=\"elementor-tab-title\" data-tab=\"2\" role=\"tab\" aria-controls=\"elementor-tab-content-1412\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">3.1.2 More information on landslides causes<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-1412\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"2\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-1412\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"2278\" class=\"elementor elementor-2278\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-2d524a6 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"2d524a6\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-9ec3208\" data-id=\"9ec3208\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-41f19e4 elementor-widget elementor-widget-text-editor\" data-id=\"41f19e4\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>By Alessandro Pasuto1, Mauro Soldati2, &amp; Doriano Castaldini2<br \/>1 CNR &#8211; IRPI Padova (Italy)<br \/>2 Dipartimento di Scienze della Terra, Universit\u00e0 di Modena e Reggio Emilia (Italy)<\/p><p>As regards the causes of mass movements, they can be divided into two large categories:<\/p><ul><li>internal causes: they lead to the failure of the slope without the intervention of perceptible changes on the surface; they are in fact causes which reduce the material&rsquo;s shear strength;<\/li><li>external causes: they determine an increase of the shear stresses by means of more or less evident modifications of slope morphology.<\/li><\/ul><p>Naturally, the factors belonging to these two categories can be combined to varying extents so they do not fit in with any particular classification.<\/p><p>Let us now consider more in detail the internal causes which condition the stability of a slope.<\/p><ul><li>Geological factors.<\/li><li>Morphological features.<\/li><li>Climatic conditions.<\/li><\/ul><p>As regards external causes which result in an increase of shear stresses, those processes giving rise to changes in slope geometry, mainly with an increase of the gradient, should first be considered. Among these processes the following are particularly important:<\/p><ul><li>Undercutting due to the erosion of a watercourse or to the excavation for road construction,<\/li><li>Exploitation of quarries or open pits<\/li><li>Overloading<\/li><li>emoval of lateral support<\/li><li>Lateral pressure<\/li><li>Tectonic activity<\/li><li>Effect of vegetation<\/li><\/ul><p>External causes are related to driving forces (Geometrical changes, Unloading, Loading, Shocks and vibrations). They determine an increase of the shear stresses by means of more or less evident modifications of slope morphology. Internal causes are related to resisting forces (Progressive failure, Weathering, Seepage erosion, Water regime change). They lead to the failure of the slope without the intervention of perceptible changes on the surface; they are in fact causes which reduce the material&rsquo;s shear strength<\/p><p><strong>Geological factors.<\/strong><br \/>They are given by all the primary characteristics that make up a slope, first of all lithology which includes both the rock&rsquo;s mineralogical and textural composition and its structure. Among rock types more easily subject to disarrangement phenomena, clays are to be quoted, both those of primary origin and those derived from the meteoric weathering of volcanic materials. Argillaceous soils are particularly subject to instability phenomena such as flows.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-c72ad9c elementor-widget elementor-widget-image\" data-id=\"c72ad9c\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"610\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/1_soilslipscassiano-1024x610.jpg\" class=\"attachment-large size-large wp-image-2283\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/1_soilslipscassiano-1024x610.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/1_soilslipscassiano-300x179.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/1_soilslipscassiano-768x457.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/1_soilslipscassiano-1536x914.jpg 1536w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/1_soilslipscassiano.jpg 1984w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-eaba50e figure-caption elementor-widget elementor-widget-text-editor\" data-id=\"eaba50e\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p style=\"text-align: center;\"><em>Fig. 1: Superficial earth slide (Soil slip) in weathered volcanic materials at S. Cassiano, Dolomites, E Alps, Italy (photo by M. Marchetti)<\/em><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-5b0afad elementor-widget elementor-widget-image\" data-id=\"5b0afad\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"766\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2a_DSCN8552-1024x766.jpg\" class=\"attachment-large size-large wp-image-2288\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2a_DSCN8552-1024x766.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2a_DSCN8552-300x225.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2a_DSCN8552-768x575.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2a_DSCN8552-1536x1150.jpg 1536w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2a_DSCN8552.jpg 1578w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-a16f4d1 elementor-widget elementor-widget-image\" data-id=\"a16f4d1\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"766\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2b_DSCN1980franPratog-1024x766.jpg\" class=\"attachment-large size-large wp-image-2293\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2b_DSCN1980franPratog-1024x766.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2b_DSCN1980franPratog-300x225.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2b_DSCN1980franPratog-768x575.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2b_DSCN1980franPratog-1536x1150.jpg 1536w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2b_DSCN1980franPratog.jpg 1578w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-e7f8ef2 figure-caption elementor-widget elementor-widget-text-editor\" data-id=\"e7f8ef2\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p style=\"text-align: center;\"><em>Fig. 2: Earth flows in clay materials in the Torrent Tiepido valley, Northern Apennines Italy (photos by D. Castaldini)<\/em><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-092a2fa elementor-widget elementor-widget-text-editor\" data-id=\"092a2fa\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Also the structure of the formation involved is very important. For example, formations made up of alternating layers, such as flysch, where rock types showing ductile mechanical behaviour overlie brittle rocks, are usually subject to widespread and vast landslides. Also discontinuities, both primary (bedding planes) and secondary (schistosity and foliation planes), play an important role in the materials&rsquo; geomechanical behaviour especially with regard to mass movements such as the attitude of layers (low-angle dip-downstream beds will generally be more prone to sliding than dip-upstream levels).<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-f782b9a elementor-widget elementor-widget-image\" data-id=\"f782b9a\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"686\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/3_98C5-1024x686.jpg\" class=\"attachment-large size-large wp-image-2300\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/3_98C5-1024x686.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/3_98C5-300x201.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/3_98C5-768x514.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/3_98C5-1536x1029.jpg 1536w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/3_98C5.jpg 1763w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 3: Rock block slide in formation made up of alternating layers with low-angle dip-downstream beds, Northern Apennines, Italy (photo Archivio CNR-IRPI, Torino)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-a54dd7a elementor-widget elementor-widget-text-editor\" data-id=\"a54dd7a\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Of course, all these intrinsic characteristics of the materials can undergo changes of varying intensity and rapidity during the stages of a slope&rsquo;s evolution. In fact, certain kinds of processes which to some extent modify the materials&rsquo; chemico-physical characteristics can take place, causing a consequent decrease of shear strength. Among geological factors, also the tectonic history of the slope should be considered. The presence of important structural discontinuities such as faults, fractures, cleavage, joints, slickenside or even folds, fault-folds etc. induce an intrinsic weakness of the internal bonds thus making the slope particularly prone to landsliding.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-24de610 elementor-widget elementor-widget-image\" data-id=\"24de610\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"766\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/4a_BB050516-039-1024x766.jpg\" class=\"attachment-large size-large wp-image-2305\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/4a_BB050516-039-1024x766.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/4a_BB050516-039-300x225.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/4a_BB050516-039-768x575.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/4a_BB050516-039-1536x1150.jpg 1536w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/4a_BB050516-039.jpg 1578w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-ac8c717 elementor-widget elementor-widget-image\" data-id=\"ac8c717\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"766\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/4b_BB050516044-1024x766.jpg\" class=\"attachment-large size-large wp-image-2310\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/4b_BB050516044-1024x766.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/4b_BB050516044-300x225.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/4b_BB050516044-768x575.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/4b_BB050516044-1536x1150.jpg 1536w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/4b_BB050516044.jpg 1578w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-3fd8611 figure-caption elementor-widget elementor-widget-text-editor\" data-id=\"3fd8611\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p style=\"text-align: center;\"><em>Fig. 4: Rock fall (below) in fractured volcanic formation (above) at Bletterbach Gorge, Northern Italy (photos by D. Castaldini)<\/em><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-93eb62a elementor-widget elementor-widget-text-editor\" data-id=\"93eb62a\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><strong>Morphological features.<\/strong><br \/>They include first of all the slope geometry, i.e. its height, length, shape, slope angle and aspect. The influence of the slope gradient is quite evident with respect to stability; indeed, very vast and steep slopes are more predisposed to disarrangement; on the other hand, even low-angle slopes can be subject to particular types of landsliding such as, for example, flows.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-9b1e8b3 elementor-widget elementor-widget-image\" data-id=\"9b1e8b3\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"667\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/5_lavilla-1024x667.jpg\" class=\"attachment-large size-large wp-image-2316\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/5_lavilla-1024x667.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/5_lavilla-300x196.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/5_lavilla-768x501.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/5_lavilla-1536x1001.jpg 1536w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/5_lavilla.jpg 1812w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 5: Incipient earth flow in low-angle slope made up of predominantly fine material, La Villa, Dolomites, E Italian Alps (photo by M. Marchetti)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-2df78f5 elementor-widget elementor-widget-text-editor\" data-id=\"2df78f5\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><strong style=\"font-size: 1rem; text-align: left;\">Climatic conditions.<\/strong><\/p><p>Although there are several climatic parameters playing some role in the starting of landslides, the most important one is without doubt rainfall. Rainfall should be considered not only as the triggering pluviometric event (considering therefore only its intensity) but also as the amount of rain falling and accumulating during a certain period (considering also the length of time). If the percolation velocity is low, the rainfall duration assumes predominant importance for the triggering of the movement; on the contrary, in soils characterised by high hydraulic conductivity the function played by rainfall intensity becomes of paramount importance. The role of water mainly consists of an increase in porewater pressures caused by variations of the groundwater level. The cyclicity of these changes is a determining factor in weakening the internal bonds of the materials making up the slope. The influence of the various types of rainfall will of course be different according to the type of landslide. (go to 3.1.1 More details on the role of water)<\/p><p>Therefore, intense and time-concentrated rainfall will be particularly effective in triggering spatially limited movements such as debris flows, soil slips, mud flows, whilst prolonged precipitations could mainly give rise to slides and complex phenomena.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-2550169 elementor-widget elementor-widget-image\" data-id=\"2550169\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"1006\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/6a_Noasca-Arianas-1024x1006.jpg\" class=\"attachment-large size-large wp-image-2322\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/6a_Noasca-Arianas-1024x1006.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/6a_Noasca-Arianas-300x295.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/6a_Noasca-Arianas-768x755.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/6a_Noasca-Arianas.jpg 1202w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-ca0b96c elementor-widget elementor-widget-image\" data-id=\"ca0b96c\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"689\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/6b_soil-slip_cebano-1024x689.jpg\" class=\"attachment-large size-large wp-image-2327\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/6b_soil-slip_cebano-1024x689.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/6b_soil-slip_cebano-300x202.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/6b_soil-slip_cebano-768x517.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/6b_soil-slip_cebano-1536x1034.jpg 1536w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/6b_soil-slip_cebano.jpg 1755w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-2649529 figure-caption elementor-widget elementor-widget-text-editor\" data-id=\"2649529\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p style=\"text-align: center;\"><em>Fig. 6: Examples of debris flow and soil slip, following an intense rainy period in autumn 1994, which caused roads interruptions Piemonte Region, NW Italy) (photos by F. Luino)<\/em><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-f6b6cc6 elementor-widget elementor-widget-image\" data-id=\"f6b6cc6\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"696\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/7_CommEpiscopio-1024x696.jpg\" class=\"attachment-large size-large wp-image-2333\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/7_CommEpiscopio-1024x696.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/7_CommEpiscopio-300x204.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/7_CommEpiscopio-768x522.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/7_CommEpiscopio-1536x1044.jpg 1536w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/7_CommEpiscopio.jpg 1738w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 7: Episcopio, Campania, Southern Italy: aerial views of the mud flows which occured on 5th and 6th May 1998, following a period of prolonged rainfall (photo by Commissariato di Governo per l\u2019Emergenza Idrogeologica in Campania, http:\/\/www.commissario2994.it)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-11d7410 elementor-widget elementor-widget-text-editor\" data-id=\"11d7410\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">As regards external causes which result in an increase of shear stresses, those processes giving rise to changes in slope geometry, mainly with an increase of the gradient, should first be considered. Among these processes the following are particularly important:<\/span><\/p><ul><li>Undercutting due to the erosion of a watercourse or to the excavation for road construction,<\/li><li>Exploitation of quarries or open pits<\/li><li>Overloading<\/li><li>Removal of lateral support<\/li><li>Lateral pressure<\/li><li>Tectonic activity<\/li><li>Effect of vegetation<\/li><\/ul>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-c3c81f8 elementor-widget elementor-widget-image\" data-id=\"c3c81f8\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"766\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/8_FraPanRoncob-1024x766.jpg\" class=\"attachment-large size-large wp-image-2339\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/8_FraPanRoncob-1024x766.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/8_FraPanRoncob-300x225.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/8_FraPanRoncob-768x575.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/8_FraPanRoncob-1536x1150.jpg 1536w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/8_FraPanRoncob.jpg 1578w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 8: Rotational earth slide in clay formation due to the erosion of the River Panaro at the foot of the slope. Northern Apennines, Italy (photo by D. Castaldini)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-e2a3ddd elementor-widget elementor-widget-image\" data-id=\"e2a3ddd\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"766\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/9_DSCN0911cavaRoncobot-1024x766.jpg\" class=\"attachment-large size-large wp-image-2344\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/9_DSCN0911cavaRoncobot-1024x766.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/9_DSCN0911cavaRoncobot-300x225.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/9_DSCN0911cavaRoncobot-768x575.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/9_DSCN0911cavaRoncobot-1536x1150.jpg 1536w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/9_DSCN0911cavaRoncobot.jpg 1578w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 9: Earth slides in clay formation due to exploitation of a quarry located in the same area of Fig.7 River Panaro valley, Northern Apennines, Italy (photo by D. Castaldini)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-68c835e elementor-widget elementor-widget-image\" data-id=\"68c835e\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"766\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/10_DSCN9746EriceiraRF-1024x766.jpg\" class=\"attachment-large size-large wp-image-2349\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/10_DSCN9746EriceiraRF-1024x766.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/10_DSCN9746EriceiraRF-300x225.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/10_DSCN9746EriceiraRF-768x575.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/10_DSCN9746EriceiraRF-1536x1150.jpg 1536w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/10_DSCN9746EriceiraRF.jpg 1578w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 10: Rock fall due to the erosion of the Atlantic Ocean at the foot of the cliff. Ericeira, Central coast of Portugal (photo by D. Castaldini)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-f45dcba elementor-widget elementor-widget-text-editor\" data-id=\"f45dcba\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">Slope geometry can change also because of phenomena taking place underground: for example, the formation of large cavities owing to mineral chemical solution or squeezing out of underlying ductile materials.<\/span><\/p><p>Overloading can be another phenomenon inducing an increase of applied shear stresses. This can happen owing to both natural causes, such as soil imbibition by rain or snow melt, accumulation of materials from volcanic eruptions, avalanches, debris flow or other movements, types of vegetation etc., or human activities as, for example, in embankment construction, buildings or other structures, in accumulation of tailings from mines and pits or in lacustrine basins or artificial reservoirs.<\/p><p>Also the removal of lateral support exerting a counterthrust on the slope could be a cause of unbalance. For example, a glacier&rsquo;s withdrawal is one of the most frequent causes which determined vast post-glacial landslides in the Alps. To this category also tectonic phenomena such as activities along fault planes and subsidence should be ascribed, besides gravitational movements themselves. It is, in fact, obvious that the detachment of a portion of slope induces in the in-place material a redistribution of the stresses which can eventually cause a new movement.<\/p><p>Another factor which can favour the development of mass movements is lateral pressure. It can be exerted by water percolating into joints or by ice; also swellings due to hydratation could induce considerable lateral pressures as well as the mobilisation of residual tectonic stresses.<\/p><p>Tectonic activity can be a direct cause of slope movements in the case of regional tilting or uplift. Also in this case the effect of the tectonic process takes place essentially by means of an increase of the slope gradient. Finally, superficial deformations induced by volcanic processes can increase the shear stress within a slope also locally.<\/p><p>A particular discussion should be reserved for seismic shocks and other transitory stresses such as vibrations induced by operating machines, explosions, rock falls etc. These events can cause both a reduction of the materials&rsquo; shear strength and an increase, although temporary, of shear stresses. The former can be exemplified by phenomena such as liquefaction induced by sudden, cyclic increases of porewater pressures with a consequent instantaneous decline of the soil&rsquo;s resistance and the collapse of the slope. This happens most frequently in saturated cohesionless medium-fine materials such as sands, silts, clays etc. The increase of shear stresses is on the contrary linked to both the accelerations to which the materials are submitted during vibrations and the temporary increment of the gradient angle in unstable slopes.<\/p><p>One of the first earthquake-triggered landslide was documented as early as 372-373 B.C. when Helice, a Greek city on the northern coast of the Peloponnese, slid into the sea after having been razed to the ground.<\/p><p>Thousands other examples occurred in historical and recent times. For instance the earthquake that occurred in Friuli (eastern Italy) on 6th May, 1976, with a main shock of magnitude 6.4 and intensity IX-X (Mercalli scale), produced numerous landslides activated; they mainly consisted of rock falls and, to a lesser extent, block-slides.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-4db5b3a elementor-widget elementor-widget-image\" data-id=\"4db5b3a\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"685\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/11a_friuli-1024x685.jpg\" class=\"attachment-large size-large wp-image-2355\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/11a_friuli-1024x685.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/11a_friuli-300x201.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/11a_friuli-768x514.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/11a_friuli-1536x1028.jpg 1536w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/11a_friuli.jpg 1765w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-fe450f7 elementor-widget elementor-widget-image\" data-id=\"fe450f7\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"676\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/11b_friuli-1024x676.jpg\" class=\"attachment-large size-large wp-image-2360\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/11b_friuli-1024x676.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/11b_friuli-300x198.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/11b_friuli-768x507.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/11b_friuli-1536x1013.jpg 1536w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/11b_friuli.jpg 1790w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-cce63fe figure-caption elementor-widget elementor-widget-text-editor\" data-id=\"cce63fe\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p style=\"text-align: center;\"><em>Fig. 11: Landslides induced by the earthquake which occurred in Friuli (North- Eastern Italy) on 6th May, 1976, magnitude 6.4, intensity IX-X (photos by M. Panizza)<\/em><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-7ed42b9 elementor-widget elementor-widget-image\" data-id=\"7ed42b9\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"676\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/12a_irpinia-1024x676.jpg\" class=\"attachment-large size-large wp-image-2365\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/12a_irpinia-1024x676.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/12a_irpinia-300x198.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/12a_irpinia-768x507.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/12a_irpinia-1536x1013.jpg 1536w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/12a_irpinia.jpg 1790w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-8a99416 elementor-widget elementor-widget-image\" data-id=\"8a99416\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"672\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/12b_irpinia-1024x672.jpg\" class=\"attachment-large size-large wp-image-2370\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/12b_irpinia-1024x672.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/12b_irpinia-300x197.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/12b_irpinia-768x504.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/12b_irpinia-1536x1008.jpg 1536w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/12b_irpinia.jpg 1799w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-b73fac2 figure-caption elementor-widget elementor-widget-text-editor\" data-id=\"b73fac2\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p style=\"text-align: center;\"><em>Fig. 12: Landslides induced by the earthquake which occurred in Campania and Basilicata (Southern Italy) on 23rd November 1980, magnitude 6.8, intensity X (photos by M. Panizza)<\/em><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-ebc2f19 elementor-widget elementor-widget-text-editor\" data-id=\"ebc2f19\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">Finally, the effect of vegetation on slope stability may be twofold: sometimes it promotes stability by reducing the action of climatic agents on the slopes, protecting the soil from precipitations, wind and sunshine; it retains a considerable amount of rain water by means of leaves, branches etc. and eliminates water through evapotranspiration; runoff and erosion decrease and there is an increase in shear resistance of the slope thanks to the roots. On the other hand, the presence of vegetation may originate negative effects by increasing the load on slopes, enhancing the action of wind forces on the trees and disjointing the soil through the action of tree roots which widen cracks and favour infiltration.<\/span><\/p><p><strong>References:<\/strong><\/p><p>PASUTO S. and SOLDATI M. Landslide Hazard in PANIZZA M (1996). Environmental Geomorphology. Developments in Earth Surface Processes 4. Elsevier Science B.V., 180 -187, Amsterdam.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-1413\" class=\"elementor-tab-title\" data-tab=\"3\" role=\"tab\" aria-controls=\"elementor-tab-content-1413\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">3.1.3 More details on safety factor<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-1413\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"3\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-1413\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"2376\" class=\"elementor elementor-2376\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-979e108 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"979e108\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-cbcc878\" data-id=\"cbcc878\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-c89734f elementor-widget elementor-widget-text-editor\" data-id=\"c89734f\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>A slope is stable when the resisting forces are superior or equal to the driving forces (or destabilising forces). The ratio between resisting forces and driving forces is the safety factor F. It is conventionally taken as the measure for the stability of a slope. Parameters involved in calculation of the safety factor can be summarized with figure 1 (from Besson, 2005):<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-e2a0860 elementor-widget elementor-widget-image\" data-id=\"e2a0860\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"734\" height=\"404\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/sumo.jpg\" class=\"attachment-large size-large wp-image-2379\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/sumo.jpg 734w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/sumo-300x165.jpg 300w\" sizes=\"(max-width: 734px) 100vw, 734px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-1fb045a elementor-widget elementor-widget-text-editor\" data-id=\"1fb045a\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>With:<br \/>Sumo is the overload<br \/>The other man is the thrust force<br \/>P: weight of material (force)<br \/>Zoom corresponds to the characteristic of the slipping contact surfaces<\/p><p>Resisting forces:<br \/>Pn: normal component of P<br \/>Normal component of the overload (Pn)<br \/>Normal component of the thrust force (Pn)<\/p><p>Driving forces (or destabilising forces):<br \/>Pt: tangential component of P<br \/>U1 and U2: hydrostatic pressure due to the \u201cArchimedes thrust\u201d<br \/>E: flow pressure<br \/>Tangential component of the overload (Pt)<br \/>Tangential component of the thrust force (Pt)<br \/>The safety factor is also defined as the ratio between shear stress and shear strength in a loaded mass:<br \/>F =1\/\uf074\/\uf0740<br \/>With \uf074 = available shear strength and \uf0740 = shear stress at the speed of 0<\/p><p>Shear strength: cohesion and effective inter-particle friction; internal resistance of a material to shear stress. The shear strength is function of temperature, confining pressure, shape, size, loading rate and amount of pores. It is an important parameter in the determination of engineering and geomorphic properties of materials.<br \/>Shear stress: two perpendicular loads or stresses applied tangential to the surface of material, producing angular deformation in the material.<\/p><p>A safety factor less than or equal to1 indicates that the slope is instable. Indeed, as the shear stress approaches the maximum available shear strength, the safety factor becomes 1 and failure is imminent. If the slope is destabilized by triggering factors (earthquake, rainfall, etc.), the apparent increase of the shear stress over the available shear strength is equivalent to the acceleration of the sliding mass. Three stages can be distinguished (figure 2):<\/p><ul><li>Stable, F&gt;1,5: the margin of stability of the slope is sufficiently high to withstand all destabilising forces;<\/li><li>Marginally stable, 1,0<\/li><li>Actively unstable, F~1,0: destabilising forces produce acceleration of the sliding mass (continuous or intermittent movements).<\/li><\/ul><p>Moreover, safety factor value is time-dependent (figure 2). The movement phase is split into pre-failure, failure and post-failure stages with the possibilities of occasional reactivation. All types of movements at a given stage are associated with specific controlling variables that are subdivided into predisposition and triggering factors. Slope instability responds to a combination of these factors. The predisposition factors change most times only gradually over time whereas the triggering factors are transient. Triggering factors may either increase the shear stress, decrease the shear strength of the material or both.\u00a0<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-2df25af elementor-widget elementor-widget-image\" data-id=\"2df25af\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"755\" height=\"349\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig2_safety-factor_van-asch.jpg\" class=\"attachment-large size-large wp-image-2384\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig2_safety-factor_van-asch.jpg 755w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig2_safety-factor_van-asch-300x139.jpg 300w\" sizes=\"(max-width: 755px) 100vw, 755px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 2: Evolution of safety factor through time &#8211; time influence of predisposition and triggering factors on instability (from Van Asch et al., 2007)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-4350b2f elementor-widget elementor-widget-text-editor\" data-id=\"4350b2f\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><strong style=\"font-size: 1rem; text-align: left;\">References:<\/strong><\/p><p>BESSON L., 2005. Les risques naturels: de la connaissance pratique \u00e0 la gestion administrative. Editions Techni. Cit\u00e9s, Voiron, 60 p.<\/p><p>VAN ASCH T., MALET J.P., VAN BEEK L., AMITRANO D., 2007. Techniques, issues and advances in numerical modelling of landslide hazard. Bulletin de la soci\u00e9t\u00e9 g\u00e9ologique de France, n\u00b0178, p. 265-288<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p>\n<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-2084\" class=\"elementor-tab-title\" data-tab=\"4\" role=\"tab\" aria-controls=\"elementor-tab-content-2084\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">4. O\u00f9 les glissements de terrain se produisent-ils ?<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-2084\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"4\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-2084\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"7925\" class=\"elementor elementor-7925 elementor-2391\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-cd28a30 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"cd28a30\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-fbbc799\" data-id=\"fbbc799\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-3e3e8a6 elementor-widget elementor-widget-text-editor\" data-id=\"3e3e8a6\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Ces ph\u00e9nom\u00e8nes sont g\u00e9n\u00e9ralement observ\u00e9s dans les montagnes ou les r\u00e9gions c\u00f4ti\u00e8res, o\u00f9 les pentes et falaises sont les plus instables. Mais on les rencontre \u00e9galement en plaine ou sur les plateaux, lorsque les sous-sols sont surexploit\u00e9s ou affaiblis.<\/p>\n<p>Les glissements de terrain peuvent \u00eatre\u00a0:<\/p>\n<ul>\n<li><em>a\u00e9riens\u00a0<\/em>(ph\u00e9nom\u00e8ne se manifestant au-dessus du sol et affectant les objets se trouvant \u00e0 sa surface) ou<\/li>\n<li><em>sous-marins<\/em>.<\/li>\n<\/ul>\n<p>On note une nette augmentation des catastrophes naturelles, et des glissements de terrain en particulier, depuis la fin du si\u00e8cle dernier.<\/p>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-a5651ac elementor-widget elementor-widget-image\" data-id=\"a5651ac\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"766\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/DSCN9576FranaHinterstein-1024x766.jpg\" class=\"attachment-large size-large wp-image-2397\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/DSCN9576FranaHinterstein-1024x766.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/DSCN9576FranaHinterstein-300x224.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/DSCN9576FranaHinterstein-768x575.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/DSCN9576FranaHinterstein-1536x1149.jpg 1536w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/DSCN9576FranaHinterstein-2048x1532.jpg 2048w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Panoramic view of a landslide in the Ostrachtal near Hinterstein (Bavaria, Germany) (Photo by D. Castaldini)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-ef29dd7 elementor-widget elementor-widget-text-editor\" data-id=\"ef29dd7\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Des glissements de terrain de grande ampleur se produisent un peu partout dans le monde. Le tableau ci-dessous r\u00e9pertorie quelques-uns des \u00e9v\u00e9nements de ce type les plus meurtriers du XX<sup>e\u00a0<\/sup>si\u00e8cle :<\/p>\n<p>&nbsp;<\/p>\n<p>Les glissements de terrain les plus graves se sont d\u00e9clench\u00e9s sous l\u2019effet d\u2019un s\u00e9isme ou d\u2019une \u00e9ruption volcanique.<\/p>\n<p>L\u2019un d\u2019entre eux a eu lieu au P\u00e9rou en 1970, sur les pentes du mont Huascar\u00e1n (au nord du P\u00e9rou) lorsque, par suite d\u2019un s\u00e9isme, une avalanche de d\u00e9bris a enseveli les villes de Yungay et de Ranrahirca. Le bilan en pertes humaines s\u2019\u00e9leva \u00e0 18\u00a0000 victimes pour l\u2019avalanche seule, et \u00e0 66\u00a0000 en tout, en comptant celles dues au s\u00e9isme. Le m\u00eame ph\u00e9nom\u00e8ne s\u2019\u00e9tait d\u00e9j\u00e0 produit en 1962, faisant 5\u00a0000 victimes.<\/p>\n<p>Le plus important glissement de terrain de l\u2019histoire, en termes de volumes de mat\u00e9riaux gliss\u00e9s, eut lieu en 1980 lorsque le mont Saint Helens, un volcan de la cha\u00eene des Cascades (\u00c9tat de Washington, \u00c9tats-Unis) entra en \u00e9ruption. Cette \u00e9ruption d\u00e9clencha une avalanche de roches et de d\u00e9bris d\u2019un volume total de 2,8 km\u00b3. L\u2019\u00e9vacuation permit de sauver de nombreuses vies. L\u2019avalanche tua entre 10 et 57 personnes (les chiffres varient suivant les sources), mais provoqua surtout d\u2019\u00e9normes d\u00e9g\u00e2ts mat\u00e9riels (logements, routes, etc.).<\/p>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-040879e elementor-widget elementor-widget-image\" data-id=\"040879e\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"758\" height=\"451\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Mount-S-Helen.jpg\" class=\"attachment-large size-large wp-image-2403\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Mount-S-Helen.jpg 758w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Mount-S-Helen-300x178.jpg 300w\" sizes=\"(max-width: 758px) 100vw, 758px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">The Mount St. Helen rock slide-debris avalanche ( http:\/\/www.fs.fed.us\/gpnf\/global\/images\/20070727-1401-hd-lg.jpg)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-8780c6e elementor-widget elementor-widget-text-editor\" data-id=\"8780c6e\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>En Europe, le glissement de terrain le plus meurtrier eut lieu le 9 octobre 1963 au barrage de Vajont, en Italie, lorsqu\u2019une avalanche de roches (270 millions de m<sup>3<\/sup>) se d\u00e9clencha lors de son remplissage. Les rochers termin\u00e8rent leur course folle dans le lac artificiel, formant des vagues de plus de 100 m\u00e8tres. Celles-ci franchirent le barrage de Vajont, coururent le long de l\u2019\u00e9troite gorge du m\u00eame nom puis s\u2019abattirent sur les villages de Longarone et d\u2019autres villages bordant la vall\u00e9e du Piave. 1\u00a0909 personnes trouv\u00e8rent la mort.<\/p>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-98280ee elementor-widget elementor-widget-accordion\" data-id=\"98280ee\" data-element_type=\"widget\" data-widget_type=\"accordion.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<div class=\"elementor-accordion\" role=\"tablist\">\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-1591\" class=\"elementor-tab-title\" data-tab=\"1\" role=\"tab\" aria-controls=\"elementor-tab-content-1591\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">4.1. More information on Where do landslides occur<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-1591\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"1\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-1591\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"2409\" class=\"elementor elementor-2409\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-113da53 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"113da53\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-49cee0a\" data-id=\"49cee0a\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-6ea5b6c elementor-widget elementor-widget-text-editor\" data-id=\"6ea5b6c\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\tAs these phenomena are usually to be found in mountain or coastal regions owing to the instability of slopes and cliffs as well as on plains and plateaux when associated with the use or dissolution of the sub-soil, they can happen all over the world.\n\nSlides can occur in various areas. In hilly and mountainous regions, many shallow slides occur in depressions or small valleys, where slopes converge because it corresponds to preferential location of water. Mountainous marly and clayey slopes are often affected by shallow or deep slides. In these materials, slides are classically associated with gullies. An example is the Barcelonnette Basin, in the French Southern Alps, affected by both slides and gullying processes since several centuries. Rotational slides generally occur in homogeneous loosed formations (substratum or superficial deposits). Slides are also often associated with flows in materials such as marl, flysch, clay, schist. Near St-Jean-de-Maurienne, in France, flows and slides mainly occur on schistose slopes. Many coastal slides exist in Normandy, France. Sub-marine slides also occur. Falls, by definition, occur on steep slopes or cliffs. Moreover, climatic factors play a direct part in the triggering of falls, in particular the alternate freezing and thawing of infiltrated water, which is particularly active in high mountainous areas or at high latitudes.\n\nFalls affect sedimentary (limestone, sandstone), eruptive (basalt, dolerite) or metamorphic (schist) rocks. In the latter the exfoliation into small columns may provoke slow tilting which gives rise to colluvial deposits. As for falls, topples occur on steep slopes or cliffs. Topples in rocks usually require high cliffs, whereas topples in debris and soil fail on lower cliffs. Topples are frequent in coherent, tectonised and fractured rocks. Topples affect sedimentary (limestone, sandstone), eruptive (basalt, dolerite) or metamorphic (schist) rocks. In the latter the exfoliation into small columns may provoke slow tilting which gives rise to colluvial deposits. Loose earth types prone to topples include more or less compacted sand and clayey soils in which desiccation and humidification cracks may appear.\n\nFlows occur in highly fractured rocks, clastic debris in a fine matrix or a simple, usually fine, grain size. Debris flows and debris avalanches usually start in the upper parts of slopes from slides (debris slide, slab slide) in loose unconsolidated rocks and soil debris, especially where the vegetative cover has been removed by logging or fire. They are also frequent in topographic concavities or hollows at first-order watersheds. This geometry favours the accumulation of colluvium and the convergence of groundwater flow necessary to cause the failure. Soil flows occur in wet sands or in silty-clays which are so reworked with water or so liquefied by structural collapse that they adopt a flow mode. Soil flows may also occur in dry sand (dry sand flow); these are potentially very destructive but very rare. They originate when large masses of dry non-cohesive fine-grained material fall from steep slopes and fluidise on impact. Rock flows are produced only where slopes are high enough to induce strong gravitational stress in the bedrock. Such condition is typical of valley slopes in strongly uplifted areas, mountain fronts, high coastal cliffs and recently deglaciated mountain areas.\n\nThere are a lot of large landslides all over the world. To have an idea is possible to see the short list below on the worldwide catastrophic landslides of the 20th century :\n\n<div class=\"table-responsive\">\n<table class=\"table table-striped\">\n<thead>\n<tr>\n<th>Year<\/th>\n<th>Place<\/th>\n<th>Event<\/th>\n<th>Cause<\/th>\n<th>Deaths<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>1933<\/td>\n<td>Sichuan, Deixi<\/td>\n<td>landslide<\/td>\n<td>EQ* M=7.5<\/td>\n<td>6800<\/td>\n<\/tr>\n<tr>\n<td>1949<\/td>\n<td>Tadzhik, Kahit<\/td>\n<td>rock slide<\/td>\n<td>EQ* M=7.5<\/td>\n<td>ca 15000<\/td>\n<\/tr>\n<tr>\n<td>1958<\/td>\n<td>Japan, Kanogawa<\/td>\n<td>debris flow<\/td>\n<td>Typhoon<\/td>\n<td>1094<\/td>\n<\/tr>\n<tr>\n<td>1962<\/td>\n<td>Peru Huascaran<\/td>\n<td>debris aval.<\/td>\n<td>?<\/td>\n<td>ca 5000<\/td>\n<\/tr>\n<tr>\n<td>1962<\/td>\n<td>Peru Huascaran<\/td>\n<td>debris aval.<\/td>\n<td>?<\/td>\n<td>ca 5000<\/td>\n<\/tr>\n<tr>\n<td>1963<\/td>\n<td>Italy , Vaiont<\/td>\n<td>rock slide<\/td>\n<td>Reservoir fillin<\/td>\n<td>1909<\/td>\n<\/tr>\n<tr>\n<td>1964<\/td>\n<td>Alaska<\/td>\n<td>slides<\/td>\n<td>EQ* M= 9.4<\/td>\n<td><\/td>\n<\/tr>\n<tr>\n<td>1970<\/td>\n<td>Peru, Huascaran<\/td>\n<td>debris aval.<\/td>\n<td>EQ* M=7.7<\/td>\n<td>18000<\/td>\n<\/tr>\n<tr>\n<td>1980<\/td>\n<td>Washington<\/td>\n<td>debris aval.<\/td>\n<td>Volcanic<\/td>\n<td><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n*Earthquake\n\nMany of the catastrophic landslides occurred as an effect induced by earthquakes and volcanic eruptions. For more details go to 4.1.1. Catastrophic landslides of the 20th century worldwide or to\u00a0<a href=\"http:\/\/landslides.usgs.gov\/learning\/majorls.php\" target=\"_blank\" rel=\"noopener\">http:\/\/landslides.usgs.gov\/learning\/majorls.php<\/a>\n\nOne of the most worldwide catastrophic landslides has been the debris avalanche from Nevado Huascaran, in the northern coast of Peru&rsquo;. In 1970, an earthquake-induced a debris avalanche on Mt. Huascaran which buried the towns of Yungay and Ranrahirca. The death toll from the Debris Avalanche was 18,000 (total fatalities from the earthquake and the debris flow was 66,000). The avalanche started as a sliding mass of glacial ice and rock about 3,000 feet wide and one mile long. The avalanche swept about 11 miles to the village of Yungay at an average speed of about 280 km\/h. The fast-moving mass picked up glacial deposits and by the time it reached Yungay, it is estimated to have consisted of about 80 million cubic yards of water, mud, and rocks. The same phenomenon occurred in the same place on 1962 and caused ca 5000 deaths.\n\nFor more details on 1962 and 1970 phenomena go to\n<a href=\"http:\/\/news.bbc.co.uk\/onthisday\/hi\/dates\/stories\/january\/11\/newsid_3306000\/3306665.stm\" target=\"_blank\" rel=\"noopener\">http:\/\/news.bbc.co.uk\/onthisday\/hi\/dates\/stories\/january\/11\/newsid_3306000\/3306665.stm<\/a>\n<a href=\"http:\/\/landslides.usgs.gov\/learning\/photos\/international\/peru_earthquake_mt._huascaran_1970\/nevadohuascaran.gif\" target=\"_blank\" rel=\"noopener\">http:\/\/landslides.usgs.gov\/learning\/photos\/international\/peru_earthquake_mt._huascaran_1970\/nevadohuascaran.gif<\/a>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-739376f elementor-widget elementor-widget-image\" data-id=\"739376f\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"335\" height=\"481\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/4-1-1970.jpg\" class=\"attachment-large size-large wp-image-2413\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/4-1-1970.jpg 335w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/4-1-1970-209x300.jpg 209w\" sizes=\"(max-width: 335px) 100vw, 335px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Image of the 1970 debris avalanche from Mt. Huascaran (Peru&rsquo;) (Photo courtesy of Servicio Aerofotografico Nacional de Peru, 13 June 1970; from http:\/\/news.bbc.co.uk\/onthisday\/hi\/dates\/stories\/january\/11\/newsid_3306000\/3306665.stm)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-b994e2e elementor-widget elementor-widget-text-editor\" data-id=\"b994e2e\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Anyhow, the world&rsquo;s biggest historic landslide, in terms of volume of material involved, occurred during the 1980 eruption of Mount St. Helens, a volcano in the Cascade Mountain Range in the State of Washington. USA. It has been a rock slide &#8211; debris avalanche and the volume of material was 2.8 km\u00b3. The phenomenon began as rock slide deteriorated into 23-km-long debris avalanche with average velocity of 125 km\/hr.;surface remobilized into 95-km-long debris flow The evacuation saved lives; in fact, the rock slide &#8211; debris avalanche took low deaths (only between 10 and 57 human fatalities, according to different information sources) but major destruction of homes, highways, etc.occurred<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-de83bb4 elementor-widget elementor-widget-image\" data-id=\"de83bb4\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"758\" height=\"451\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Mount-S-Helen.jpg\" class=\"attachment-large size-large wp-image-2403\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Mount-S-Helen.jpg 758w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Mount-S-Helen-300x178.jpg 300w\" sizes=\"(max-width: 758px) 100vw, 758px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">The Mount St. Helen rock slide &#8211; debris avalanche (Photo by http:\/\/www.fs.fed.us\/gpnf\/global\/images\/20070727-1401-hd-lg.jpg)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-7f98b0d elementor-widget elementor-widget-text-editor\" data-id=\"7f98b0d\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>For more information go to<br \/><a href=\"http:\/\/pubs.usgs.gov\/fs\/2000\/fs036-00\/\" target=\"_blank\" rel=\"noopener\">http:\/\/pubs.usgs.gov\/fs\/2000\/fs036-00\/<\/a><br \/><a href=\"http:\/\/news.bbc.co.uk\/onthisday\/hi\/dates\/stories\/may\/19\/newsid_2511000\/2511133.stm\" target=\"_blank\" rel=\"noopener\">http:\/\/news.bbc.co.uk\/onthisday\/hi\/dates\/stories\/may\/19\/newsid_2511000\/2511133.stm<\/a><\/p><p>As concerns Europe, the largest catastrophic landslide was the rock slide (volume of 270 million m3) which on 9 october 1963, with high-velocity, fall into Vaiont Reservoir (see photo in the Landslides introductory page). It caused 100-m-high waves that overtop the Vaiont Dam, channellized into the narrow Vajont gorge, plunging like a drop hammer onto Longarone and other villages along the Piave River valley.<br \/>This phenomenon caused 1909 victims.<br \/>For more information go to 13.1 Vajont study case<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-6444f89 elementor-widget elementor-widget-image\" data-id=\"6444f89\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"835\" height=\"1024\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Locatio2-835x1024.gif\" class=\"attachment-large size-large wp-image-2418\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Locatio2-835x1024.gif 835w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Locatio2-245x300.gif 245w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Locatio2-768x941.gif 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Locatio2-1253x1536.gif 1253w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Locatio2-1671x2048.gif 1671w\" sizes=\"(max-width: 835px) 100vw, 835px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-3836a16 elementor-widget elementor-widget-text-editor\" data-id=\"3836a16\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Location of the main region prone to landslides in West Europe<br \/>In blue: plateaux and plains with subsidence;<br \/>In yellow: high mountains and hilly areas<\/p><p>As concern the subsidence (progressive and rapid subsidence processes) in Western Europe, accordingly to the geologic conditions which advantage this phenomenon, it is mainly located in areas:<\/p><ul><li>Where natural cavities exist, i.e. in soluble bedrocks like limestone, chalk, gypsum, salt, etc. In karst areas the creation of tunnels and cavities can be very rapid when aggressive water (i.e. water with a high content of carbonic acid) dissolves soluble rocks like gypsum or salt, . In such locations the development of large cavities can occur in a few years, whereas dissolution is much slower in limestones or chalks where the development of cavities can take far more than a hundred years;<\/li><li>Where anthropogenic cavities exist (subterranean quarries or mines), i.e. in the main coal, saline and iron basins (mining), and in many urban zones (quarries) (Link with study case Caen-Carries) because a lot of cities were built with stones or materials extracted in direct vicinity, and urbanization often forced the settlement into the zones of exploitation. Go to 4.1.2. Where subsidence occur in Western Europe<\/li><\/ul><p>Shrinking is a process caused by the desiccation of the soils due to intense and\/or long periods of dryness. Shrinking produces slow, low amplitude, vertical deformations of the ground surface. Shrinking can be followed by progressive swelling processes when soil humidity is increased in the wet seasons In many regions, these vertical movements have generated high damage to buildings, in particular to small single, individual houses. Go to 4.1.3. Where shrinking-swelling occur in France<\/p><p><strong>References:<\/strong><\/p><p>&#8211; DIKAU R., BRUNSDEN D., SCHROTT L. &amp; IBSEN M.-L. (eds.), 1996. Landslide Recognition: Identification, Movement and Causes. John Wiley &amp; Sons Ltd, Chichester FLAGEOLLET J.C., 1988. Les mouvements de terrain et leur pr\u00e9vention, Masson, Paris, 224 p.\u00a0<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-bd6e2d5 elementor-widget elementor-widget-accordion\" data-id=\"bd6e2d5\" data-element_type=\"widget\" data-widget_type=\"accordion.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<div class=\"elementor-accordion\" role=\"tablist\">\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-1981\" class=\"elementor-tab-title\" data-tab=\"1\" role=\"tab\" aria-controls=\"elementor-tab-content-1981\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">4.1.2 Where subsidence occur in Western Europe<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-1981\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"1\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-1981\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"2424\" class=\"elementor elementor-2424\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-8c86705 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"8c86705\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-8a9c94d\" data-id=\"8a9c94d\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-3431278 elementor-widget elementor-widget-text-editor\" data-id=\"3431278\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Main locations of subsidence (paragraph common to progressive and rapid subsidence processes)<\/p><p>Accordingly to the geologic conditions which advantage subsidence, it is mainly located in areas:<\/p><ul><li>Where natural cavities exist, i.e. in soluble bedrocks like limestone, chalk, gypsum, salt, etc. In karst areas the creation of tunnels and cavities can be very rapid when aggressive water (i.e. water with a high content of carbonic acid) dissolves soluble rocks like gypsum or salt, . In such locations the development of large cavities can occur in a few years, whereas dissolution is much slower in limestones or chalks where the development of cavities can take far more than a hundred years;<\/li><li>Where anthropogenic cavities exist (subterranean quarries or mines), i.e. in the main coal, saline and iron basins (mining), and in many urban zones (quarries) (Link with study case Caen-Carries) because a lot of cities were built with stones or materials extracted in direct vicinity, and urbanization often forced the settlement into the zones of exploitation.<\/li><\/ul><p>According to Embleton and Embleton (1997) to Maquaire (2005), for some countries in Western Europe the zones prone to subsidence processes are: In Luxembourg in the Walfendigen sector: Some collapses caused by natural dissolution and the mining of gypsum. In The Netherlands near Maastricht and St Pietersberg: Subsidence caused by coal mining from 1900 to the mid 1970s, and by the marl excavation since the seventeenth century. Furthermore, subsidence is still occurring in regions where oil and gas are extracted at or close to the coastline, in particularly near the Groningue basin. Further causes for subsidence in coastal areas of the Netherlands are the compaction of Holocene sediments and a decrease of the water table pressure in recent polders. These polders have been artificially filled with a one meter layer of sand to improve the state of the built-up land (Flageollet, 1988). In Germany in the region of the Hartz Mountains and along the fringes of other central German uplands (Mittelgebirge) in Hesse, Lower Saxony and Thuringia, and also at a few localities in the north German lowlands: Soluble formations in subterranean caves have collapsed (sulphate and chloritic rocks, to a lesser extent calcareous rocks) due to karst processes. Natural karst processes, which seem to have been more active in the early Tertiary and late Pleistocene, actually show only weak effects, but mining engineering, copper and salt mining, and water pumping have intensified and modified these natural processes, sometimes leading to local damage (Garleff et al., 1997). At L\u00fcneburg (Lower Saxony), 169 buildings were demolished between 1949 and 1973 because of subsidence caused by salt mining and the karstification of gypsum (Flageollet, 1988).<\/p><p>In Belgium, there are mass movements and subsidence associated with karst processes in the limestone fringe along the north of the Ardennes, in the Condroz region and also near Doornik and the region of \u201cPays de Herve\u201d (Heyse, 1997). Furthermore, collapses and subsidence due to marl excavation occur regularly since the seventeenth century in the Muizenberg, associated with the marl excavation in various part of Belgium (areas of Zichen-Zussen-Bolder, Riemst, Kanne and Hoegaarden). Coal mining causes subsidence and considerable damage to buildings, roads and infrastructure in the Campine region as well as in Wallonia, in the Borinage, and in the Li\u00e8ge Basin.<\/p><p>In France, subsidence caused by human activity has been observed in the coal basins, the Lorraine iron and salt mine, above underground quarries (marl, gypsum, chalk\u2026) in the Paris region, the North Pas-de-Calais basin, the Val-de-Loire, the Bordelais and the Touraine, the city of Caen (link Study case) ; the Pays d\u2019Auge and the plateaux in the Seine-Maritime and the Eure. The dissolution of karst also entails subsidence, in the Paris region in the gypsum, in the Orleans region in the chalk, in the Causses du Quercy, in Perigord, etc.<\/p><p><strong>Bibliography:<\/strong><\/p><p>Embleton, C., and Embleton C. (eds.) (1997), Geomorphological Hazards of Europe. Developments in Earth Surface Processes 5. Amsterdam : Elsevier, 524p.<br \/>Flageollet, J. C. (1988), Les mouvements de terrain et leur pr\u00e9vention, Paris : Masson, 224p.<br \/>Maquaire, O., (2005). Geomorphic hazards and natural risks, In: Koster, E., A. (ed.), The Physical Geography of Western Europe, Oxford Regional Environments, Oxford University Press, Chapter 18, 354-377.<br \/>Minist\u00e8re de l\u2019Ecologie et du D\u00e9veloppement Durable, 2004. Dossier d\u2019information sur le risque Mouvement de terrains, 20 p. (\u00e0 t\u00e9l\u00e9charger sur site du MEDD).<\/p><p><strong>Liens Internet :<\/strong><\/p><p><a href=\"http:\/\/fr.wikipedia.org\/wiki\/Subsidence\" target=\"_blank\" rel=\"noopener\">http:\/\/fr.wikipedia.org\/wiki\/Subsidence<\/a><br \/><a href=\"http:\/\/www.lorraine.drire.gouv.fr\/mines\/g_cadreDomaine.asp?droite=2_ApresMines.asp&amp;bas=g_MinesNavig.asp?DEST=APMINES\" target=\"_blank\" rel=\"noopener\">http:\/\/www.lorraine.drire.gouv.fr\/mines\/g_cadreDomaine.asp?droite=2_ApresMines.asp&amp;bas=g_MinesNavig.asp?DEST=APMINES<\/a><br \/><a href=\"http:\/\/www.cgm.org\/themes\/soussol\/mines\/\" target=\"_blank\" rel=\"noopener\">http:\/\/www.cgm.org\/themes\/soussol\/mines\/<\/a><br \/><a href=\"http:\/\/www.cavite.net\/\" target=\"_blank\" rel=\"noopener\">http:\/\/www.cavite.net<\/a><br \/><a href=\"http:\/\/www.prim.net\/professionnel\/documentation\/dossiers_info\/nat\/low\/mouvtTerr.pdf\" target=\"_blank\" rel=\"noopener\">http:\/\/www.prim.net\/professionnel\/documentation\/dossiers_info\/nat\/low\/mouvtTerr.pdf<\/a><br \/><a href=\"http:\/\/www.catp-asso.org\/cavites37\/pages\/missions.htm\" target=\"_blank\" rel=\"noopener\">http:\/\/www.catp-asso.org\/cavites37\/pages\/missions.htm<\/a><br \/><a href=\"http:\/\/clamart.cyberkata.org\/\" target=\"_blank\" rel=\"noopener\">http:\/\/clamart.cyberkata.org\/<\/a><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-1982\" class=\"elementor-tab-title\" data-tab=\"2\" role=\"tab\" aria-controls=\"elementor-tab-content-1982\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">4.1.3 Where shrinking-swelling occur in France<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-1982\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"2\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-1982\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"2428\" class=\"elementor elementor-2428\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-93fb70e elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"93fb70e\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-3a81cac\" data-id=\"3a81cac\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-7646995 elementor-widget elementor-widget-image\" data-id=\"7646995\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"573\" height=\"529\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/CommunesCatNat_om.jpg\" class=\"attachment-large size-large wp-image-2431\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/CommunesCatNat_om.jpg 573w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/CommunesCatNat_om-300x277.jpg 300w\" sizes=\"(max-width: 573px) 100vw, 573px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-b2a9c73 elementor-widget elementor-widget-text-editor\" data-id=\"b2a9c73\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Hence, high damage related to shrinking and swelling has been recorded. Since 1989, it is more than 5 000 communes for 75 departments, which were affected par the shrinking-swelling. This phenomenon is largely distributed. However, certain areas are more particularly affected in close relation with the geological nature of the ground. It is the case in particular of the plain of Flandres, the southern part of the Basin of Paris, the graben of Limagne, the area of Apt and especially of the whole of the molassic slopes of South-west, between Agen and Toulouse and many others to a somewhat lesser extent.<\/p><p>In the figure we could see a number of times that a commune was recognized in a \u2018state of natural disaster\u2019 (following the law of 13 July 1982) with respect to shrinking-swelling until August 15, 2006 (from\u00a0<a href=\"http:\/\/www.argiles.fr\/\" target=\"_blank\" rel=\"noopener\">http:\/\/www.argiles.fr\/<\/a>)<\/p><p><strong>References:<\/strong><br \/>Bekkouche N. et al., 1990. Foundation problems in Champlain clays during droughts: I \u2013 rainfall deficits in Montreal (1930-1988). Revue Canadienne de G\u00e9otechnique, vol. 27, n\u00b03, pp. 285-293.<br \/>Bekkouche N. et al., 1992. Foundation problems in Champlain clays during droughts: II \u2013 Cases histories. Revue Canadienne de G\u00e9otechnique, vol. 29, n\u00b02, pp. 169-187.<br \/>Biddle P.J. 1983. Pattern of soil drying and moisture deficit in the vicinity of trees on city soils. G\u00e9otechnique, vol. 33, n\u00b02, pp.107-126.<br \/>Driscoll R. 1983. The influence of vegetation on the swelling and shrinking of clay soils in Britain. G\u00e9otechnique, vol. 33, n\u00b02, pp.93-105.<br \/>Maquaire, O., 2005. Geomorphic hazards and natural risks, In: Koster, E., A. (ed.), The Physical Geography of Western Europe, Oxford Regional Environments, Oxford University Press, Chapter 18, 354-377.<br \/>Margron P., Mouroux P. &amp; Pinte J.C. 1988. La construction \u00e9conomique sur sols gonflants. BRGM-REXCOOP. BRGM Ed., Manuels et m\u00e9thodes, 125 p.<br \/>Minist\u00e8re de l\u2019Environnement, 1993, S\u00e9cheresse et construction : guide de pr\u00e9vention. La Documentation Fran\u00e7aise, 51p.<\/p><p><strong>Internet links :<\/strong><br \/><a href=\"http:\/\/www.prim.net\/professionnel\/documentation\/dossiers_info\/nat\/low\/mouvtTerr.pdf\" target=\"_blank\" rel=\"noopener\">http:\/\/www.prim.net\/professionnel\/documentation\/dossiers_info\/nat\/low\/mouvtTerr.pdf<\/a><br \/><a href=\"http:\/\/www.argiles.fr\/\" target=\"_blank\" rel=\"noopener\">http:\/\/www.argiles.fr\/<\/a><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p>\n<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-2085\" class=\"elementor-tab-title\" data-tab=\"5\" role=\"tab\" aria-controls=\"elementor-tab-content-2085\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">5. Quelles sont les cons\u00e9quences des glissements de terrain ?<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-2085\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"5\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-2085\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"7927\" class=\"elementor elementor-7927 elementor-2438\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-b046302 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"b046302\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-cff9bdc\" data-id=\"cff9bdc\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-c8ddc57 elementor-widget elementor-widget-text-editor\" data-id=\"c8ddc57\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Les risques li\u00e9s aux glissements de terrain sont souvent sous-estim\u00e9s (\u00e0 l\u2019\u00e9chelle mondiale) par rapport \u00e0 d\u2019autres types de risques\u00a0(sismiques ou volcaniques par exemple), car plus occasionnels, d\u2019amplitude moindre et aux effets plus limit\u00e9s.<\/p>\n<p>Mais certains glissements de terrain peuvent provoquer des dommages graves et co\u00fbteux en raison de leur diversit\u00e9, de leur fr\u00e9quence et de leur large r\u00e9partition g\u00e9ographique.<\/p>\n<p>Leurs cons\u00e9quences peuvent \u00eatre\u00a0:<\/p>\n<ul>\n<li><strong>directes\u00a0<\/strong>(d\u00e9t\u00e9riorations infrastructurelles ou routi\u00e8res par exemple) ;<\/li>\n<li><strong>indirectes\u00a0<\/strong>(perturbations, interruption de la circulation ferroviaire ou routi\u00e8re, etc.) assorties de pertes \u00e9conomiques aux r\u00e9percussions perceptibles bien apr\u00e8s l\u2019incident.<\/li>\n<\/ul>\n<p>En fait, il existe, outre les mouvements de terrain de forte intensit\u00e9 somme toute plut\u00f4t rares, quantit\u00e9 de glissements de terrain de taille r\u00e9duite \u00e0 moyenne, si r\u00e9pandus que leur co\u00fbt total pour la soci\u00e9t\u00e9 humaine exc\u00e8de celui des glissements les plus dommageables.<\/p>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-b2be1aa elementor-widget elementor-widget-image\" data-id=\"b2be1aa\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"664\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Franavalvenostanew-1024x664.jpg\" class=\"attachment-large size-large wp-image-2443\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Franavalvenostanew-1024x664.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Franavalvenostanew-300x194.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Franavalvenostanew-768x498.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Franavalvenostanew-1536x996.jpg 1536w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Franavalvenostanew.jpg 1822w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 1. The train derailed in a landslide occurred on 12\/04\/2010 near Merano (Alto Adige, Northern Italy) (photo by http:\/\/www.ansa.it\/)11<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-9f86794 elementor-widget elementor-widget-text-editor\" data-id=\"9f86794\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Neuf passagers sont morts et, sur les 28 bless\u00e9s, sept ont \u00e9t\u00e9 hospitalis\u00e9s. Il s\u2019agissait d\u2019un petit train diesel \u00e0 deux wagons circulant sur la ligne du val Venosta, entre Adige et montagnes. Le train \u00e9tait rempli de navetteurs et d\u2019\u00e9tudiants. Le mouvement de terrain, un glissement en surface, a \u00e9t\u00e9 caus\u00e9 par des infiltrations d\u2019eau, \u00e0 la suite de la rupture d\u2019un syst\u00e8me d\u2019irrigation souterrain dans une pommeraie. La rupture de la tuyauterie a gorg\u00e9 le terrain d\u2019eau qui, d\u00e9stabilis\u00e9, a commenc\u00e9 \u00e0 glisser. Le glissement de terrain s\u2019est produit \u00e0 une dizaine de m\u00e8tres\u00a0; il a heurt\u00e9 le train lors de son passage. Une rang\u00e9e d\u2019arbres a emp\u00each\u00e9 la rame de chuter dans l\u2019Adige, \u00e9pargnant \u00e0 ses passagers un sort encore plus tragique.<\/p>\n<p>De plus en plus de pertes sont imputables \u00e0 des activit\u00e9s humaines responsables d\u2019\u00e9v\u00e9nements de faible intensit\u00e9 mais tr\u00e8s fr\u00e9quents. Ces activit\u00e9s (travaux routiers, carri\u00e8res, etc.) tendent \u00e0 amplifier le risque de glissements de terrain en aggravant la vuln\u00e9rabilit\u00e9 de certaines zones.<\/p>\n<p>Une part consid\u00e9rable des dommages mat\u00e9riels ou humains associ\u00e9s aux s\u00e9ismes et \u00e9ruptions volcaniques est \u00e9galement due aux glissements de terrain qui en r\u00e9sultent.<\/p>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-6534b1d elementor-widget elementor-widget-image\" data-id=\"6534b1d\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"768\" height=\"1150\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_2_-Holbeck-768x1150.jpg\" class=\"attachment-medium_large size-medium_large wp-image-2448\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_2_-Holbeck-768x1150.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_2_-Holbeck-200x300.jpg 200w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_2_-Holbeck-684x1024.jpg 684w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_2_-Holbeck.jpg 946w\" sizes=\"(max-width: 768px) 100vw, 768px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig.2: The destructive failure at Holbeck hall (Hotel) in Scarborough, Yorkshire, UK (1992) (Photo by R.Moore)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-8b15735 elementor-widget elementor-widget-text-editor\" data-id=\"8b15735\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Go to 5.1 More information on consequences of landslides<\/p>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-82feccc elementor-widget elementor-widget-accordion\" data-id=\"82feccc\" data-element_type=\"widget\" data-widget_type=\"accordion.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<div class=\"elementor-accordion\" role=\"tablist\">\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-1371\" class=\"elementor-tab-title\" data-tab=\"1\" role=\"tab\" aria-controls=\"elementor-tab-content-1371\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">5.1 More information on landslides consequences<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-1371\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"1\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-1371\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"2454\" class=\"elementor elementor-2454\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-7177528 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"7177528\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-9e69ff4\" data-id=\"9e69ff4\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-fe8e854 elementor-widget elementor-widget-text-editor\" data-id=\"fe8e854\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Landslides consequences are generally lower\u00a0 compared to other types of hazards, such as seismic and volcanic hazards, as they are mostly occasional phenomena, of low amplitude and limited effects.<br \/>But some landslides cause extensive and costly damage because of their diversity, their frequency and their wide geographic distribution. These consequences could be direct (i.e. building or road damages) or indirect (i.e. perturbations, disruptions of railway, road traffic \u2026) with economic losses during long time after the event.<br \/>Historically, one of the major landslides disasters in Europe occurred in France in 1248 when a rock fall at the Mont Granier (Savoy) destroyed 5 villages killing 2000 to 5000 people.<br \/><br \/><a href=\"http:\/\/www.ccsti-chambery.org\/index_dos.htm\" target=\"_blank\" rel=\"noopener\">more details on that event &gt;&gt; http:\/\/www.ccsti-chambery.org\/index_dos.htm\u00a0<\/a>(in french).<\/p><p>But other major disasters have caused damage and cost lives in Europe during the last decades:<br \/>\u2022 Belgium 1958: Rapid subsidence of ancient subterranean quarry at Roosburg; 18 victims;<br \/>\u2022 France 1961: Rapid subsidence in Clamart &amp; Issy-les-Moulineaux; 21 victims;<br \/>\u00a0<br \/><a href=\"http:\/\/clamart.cyberkata.org\/\" target=\"_blank\" rel=\"noopener\">more details on that event &gt;&gt; http:\/\/clamart.cyberkata.org\/\u00a0<\/a>(in french)<br \/><br \/>\u2022 Belgium 1961: Flow of Jupille; 11 victims and 17 houses destroyed;<br \/>\u2022 Italy 1963: Rockslide of Vajont dam; 1909 victims<br \/>\u00a0<br \/>more details on that event &gt;&gt; Go to 13.1.Vajont Case Study<br \/><br \/>\u2022 France 1970: Mudflow of Assy plateau (Hte-Savoie); destruction of a sanatorium, 72 victims;<br \/>\u2022 France 1994: Slide, Salle-en-Beaumont (Is\u00e8re), 4 victims,<br \/>\u2022 Italy 1998: Mudflows of Sarno (Campania); 160 victims, 115 people injured and 1210 became homeless<br \/><br \/>more details on that event &gt;&gt; Go to 13.2.Sarno Case Study<\/p><p>Actually, besides high-magnitude mass movements which occur quite seldom, there is a huge number of medium to small sized landslides which are so widespread that the related cost for human society is even higher than that of catastrophic events. Increasing losses due to low-magnitude, high-frequency events are fostered by human activity which tends to increase landslide hazard (road cuts, quarries etc.) and favours vulnerability situations.<br \/>Furthermore, a considerable proportion of damage and casualties generally related to earthquakes and volcanic eruptions is due to landslides occurring as an effect induced by these phenomena.<\/p><p>Go to More details on different landslides types consequences:<br \/><a href=\"http:\/\/www.besafenet.net\/en-gb\/natural-hazards-landslides#faq82\">5.1.1. Sinking consequences<\/a><br \/><a href=\"http:\/\/www.besafenet.net\/en-gb\/natural-hazards-landslides#faq83\">5.1.2 Shrinking and swelling consequences (e.g. in France)<\/a><br \/><a href=\"http:\/\/www.besafenet.net\/en-gb\/natural-hazards-landslides#faq84\">5.1.3 Slide consequences<\/a><br \/><a href=\"http:\/\/www.besafenet.net\/en-gb\/natural-hazards-landslides#faq85\">5.1.4 Fall (rockfall avalanche, topple) consequences<\/a><br \/><a href=\"http:\/\/www.besafenet.net\/en-gb\/natural-hazards-landslides#faq86\">5.1.5 Flow consequences<\/a><br \/><br \/>Go to 5. What could be the consequences of LANDSLIDES?<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-a780475 elementor-widget elementor-widget-accordion\" data-id=\"a780475\" data-element_type=\"widget\" data-widget_type=\"accordion.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<div class=\"elementor-accordion\" role=\"tablist\">\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-1751\" class=\"elementor-tab-title\" data-tab=\"1\" role=\"tab\" aria-controls=\"elementor-tab-content-1751\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">5.1.1. More details on sinking consequences<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-1751\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"1\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-1751\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"2457\" class=\"elementor elementor-2457\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-9971c8c elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"9971c8c\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-0810c4f\" data-id=\"0810c4f\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-3e6dfab elementor-widget elementor-widget-text-editor\" data-id=\"3e6dfab\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Sinking is a very slow process of vertical deformation with a limited extent (like limited progressive subsidence). The differential deformations can be caused by:<\/p><ul><li>The natural consolidation of recent soil formations (Quaternary), under load (weight of overlying grounds and additional weight of constructions). Typical examples for constructional problems\/damage due to sinking are the Towers of Pisa and Bologna (Italy), and the Church Saint-Jean in Caen (France);<\/li><li>The lowering of groundwater table by pumping. Typical examples are the cities Mexico, Venice, and Bangkok;<\/li><li>The exploitation of fluids (like oil in California) or gas (in the Plain of the Po) in soil and rocks.<\/li><li>The alternation of humidification and desiccation cycles in clayey soils (e.g. shrinking and swelling);<\/li><li>The modification of the stresses in granular soils (liquefiable sands).<\/li><\/ul>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-e1f2707 elementor-widget elementor-widget-image\" data-id=\"e1f2707\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"268\" height=\"447\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_1_Campanile_Bologna.jpg\" class=\"attachment-large size-large wp-image-2460\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_1_Campanile_Bologna.jpg 268w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_1_Campanile_Bologna-180x300.jpg 180w\" sizes=\"(max-width: 268px) 100vw, 268px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig.1.Differential sinking beneath the foundation of the Tower of Bologna (Italy) (Photo: Maquaire, Cerg)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-509b729 elementor-widget elementor-widget-image\" data-id=\"509b729\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"768\" height=\"1026\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_2_DSCN3879pisa-768x1026.jpg\" class=\"attachment-medium_large size-medium_large wp-image-2465\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_2_DSCN3879pisa-768x1026.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_2_DSCN3879pisa-225x300.jpg 225w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_2_DSCN3879pisa-766x1024.jpg 766w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_2_DSCN3879pisa-1150x1536.jpg 1150w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_2_DSCN3879pisa.jpg 1181w\" sizes=\"(max-width: 768px) 100vw, 768px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig.2.Differential sinking affecting the Tower of Pisa (Photo: Castaldini, Cerg).<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-d187ba1 elementor-widget elementor-widget-image\" data-id=\"d187ba1\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"768\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_3_StJeanCaen02_juin06_-028_AR.jpg\" class=\"attachment-large size-large wp-image-2470\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_3_StJeanCaen02_juin06_-028_AR.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_3_StJeanCaen02_juin06_-028_AR-300x225.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_3_StJeanCaen02_juin06_-028_AR-768x576.jpg 768w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig.3.Topple and deformation of the Saint-Jean Church (Caen, France) due to a major sinking underneath its foundations. The church has been built in the XVth century in a marshy zone of the alluvial plain of the Orne River and is constructed on oak piles. As sinking has appeared during the construction phase, the high of the tower has been limited to reduce its total weight and to decrease the toppling force. (Photo: Maquaire, Cerg).<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-1752\" class=\"elementor-tab-title\" data-tab=\"2\" role=\"tab\" aria-controls=\"elementor-tab-content-1752\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">5.1.2 More details on shrinking and swelling consequences (e.g. in France)<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-1752\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"2\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-1752\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"2478\" class=\"elementor elementor-2478\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-3695bb8 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"3695bb8\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-9c71100\" data-id=\"9c71100\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-b7b22fa elementor-widget elementor-widget-text-editor\" data-id=\"b7b22fa\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Shrinking and swelling of clayey soils constitutes a natural hazard, which is indeed less spectacular than sudden and rapid landslides. However, prolonged dry conditions have caused an intense desiccation of sensitive clayey soils. The desiccation cracks reached depths of up to two meters. Subsequent soil compression was induced by an increase in soil moisture during the wet seasons, and finally swelling of the underground. In many regions, these vertical movements have generated high damage to buildings, in particular to small single, individual houses. In France, in the period between 1989 and 1992, the amount of damages was more than 2 billions of Euros. At the end of the year 2002, the total amount of refundings carried out was evaluated to approximately 3,3 billion euros, which corresponds to several hundreds of thousands of damaged houses on the whole of France since 1989.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-bd40e4d elementor-widget elementor-widget-image\" data-id=\"bd40e4d\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"381\" height=\"347\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Retrait-Gonflement.jpg\" class=\"attachment-large size-large wp-image-2481\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Retrait-Gonflement.jpg 381w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Retrait-Gonflement-300x273.jpg 300w\" sizes=\"(max-width: 381px) 100vw, 381px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-d77c159 elementor-widget elementor-widget-text-editor\" data-id=\"d77c159\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Cracks caused by shrinking of clayey soils in the Centre of France (Orl\u00e9ans region). In this specific case, the amplitude of the cracks is increased due to the presence of trees inducing root suction (differential sinking) (Photo: Maquaire, CERG)<\/p><p>Factors enforcing shrinking and swelling consequences<\/p><p>Differential compression can be amplified locally by tree or bush suction or by soil heterogeneity (in example, house partially located on sensitive clayey soils and on insensitive formation, e.g. limestone). This causes cracks and damage on bulding structures, and sometimes even the complete destruction of houses.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-70ad5fb elementor-widget elementor-widget-image\" data-id=\"70ad5fb\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"768\" height=\"614\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Shrinking_English2Converti-768x614.jpg\" class=\"attachment-medium_large size-medium_large wp-image-2486\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Shrinking_English2Converti-768x614.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Shrinking_English2Converti-300x240.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Shrinking_English2Converti-1024x818.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Shrinking_English2Converti-1536x1227.jpg 1536w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Shrinking_English2Converti-2048x1636.jpg 2048w\" sizes=\"(max-width: 768px) 100vw, 768px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-cef9d96 elementor-widget elementor-widget-text-editor\" data-id=\"cef9d96\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Shrinking-swelling process<\/p><p>Is there a specific house type which is especially vulnerable to this hazard?<br \/>The damage has often pinpointed certain deficiencies in constructions: insufficient depths of the foundations, and a high rigidity of the foundation structures and therefore inability to compensate the deformations of the underground.<\/p><p>A national analysis of approximately 800 cases has indicated the \u201ctypical\u201d vulnerable construction: an individual house with a simple ground floor, a non- or inadequately steeled strip foundation, low anchoring depths (&lt; 0.8m) in clayey soils or clayey-sandy soils, and masonry without any horizontal chaining. The susceptible soils are classed sensitive (15&lt;Ip&lt;30) to very sensitive (Ip&gt;30) according to soil humidity variations (with Ip: Plastic index).<\/p><p>Go to 5. What could be the consequences of LANDSLIDES?<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-1753\" class=\"elementor-tab-title\" data-tab=\"3\" role=\"tab\" aria-controls=\"elementor-tab-content-1753\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">5.1.3 Details on consequences of the slide process<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-1753\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"3\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-1753\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"2493\" class=\"elementor elementor-2493\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-4b99b78 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"4b99b78\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-3c1ff87\" data-id=\"3c1ff87\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-9255f8e elementor-widget elementor-widget-text-editor\" data-id=\"9255f8e\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Contrary to fall events, slide events are in most cases slow phenomenon. Thus, human losses caused by slides are exceptional, but possible (figures 2 to 5). Damages to buildings are frequent, from simple cracking to total ruin. Slides can also cause interruption of roadway systems. According to the extent of the slide phenomenon, damaged area is more or less important.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-30fc8a9 elementor-widget elementor-widget-image\" data-id=\"30fc8a9\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"820\" height=\"251\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig01_Slide_effects.jpg\" class=\"attachment-large size-large wp-image-2497\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig01_Slide_effects.jpg 820w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig01_Slide_effects-300x92.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig01_Slide_effects-768x235.jpg 768w\" sizes=\"(max-width: 820px) 100vw, 820px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 1: Different effects of a slide event on a house (modified from L\u00e9one and al., 1996<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-d4edccf elementor-widget elementor-widget-image\" data-id=\"d4edccf\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"498\" height=\"314\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig02_salleenbeaumont.jpg\" class=\"attachment-large size-large wp-image-2503\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig02_salleenbeaumont.jpg 498w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig02_salleenbeaumont-300x189.jpg 300w\" sizes=\"(max-width: 498px) 100vw, 498px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 2: House damaged by the landslide of La Salle en Beaumont, near Grenoble, France, on January 8 1994.<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-63d846c elementor-widget elementor-widget-text-editor\" data-id=\"63d846c\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">Because of very heavy rainfalls during 2 consecutive days, a 1,3 millions m3 slide triggered during the night. First a crown appeared and destroyed a house. Then a 15-meters-thick slide advanced into the gorge of a stream. Finally, 9 houses were damaged and 4 people were killed while they were sleeping (from www.irma-grenoble.com)<\/span><\/p><p>In 1985, in Puerto Rico, a 300,000 m3 rock-block-slide destroyed 120 houses and killed 129 people at least. This landslide was caused by extraordinarily heavy rainfalls during 24 hours. The landslide failed in 3 distinct phases between 3:00 and 4: am on October 7 1985. The first two phases involved 12 meters-thick translational slides. The third phase involved the toppling failure of a block that disaggregated and form a rock fall on the western part of the slide. Subsidiary flow failures onto the toe and from the downstream face of the toe were triggered by the heavy rainfalls and the rupture of a water pipe that emptied as much as 4 million litres of water onto the slide (Figures 3 to 5).<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-d7e9a9c elementor-widget elementor-widget-image\" data-id=\"d7e9a9c\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"611\" height=\"424\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig03_rockblockslide.jpg\" class=\"attachment-large size-large wp-image-2508\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig03_rockblockslide.jpg 611w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig03_rockblockslide-300x208.jpg 300w\" sizes=\"(max-width: 611px) 100vw, 611px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 3: Disrupted area above the toe of the landslide. House debris are visible on the surface (from Slosson and al., 1992)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-16e2c9e elementor-widget elementor-widget-image\" data-id=\"16e2c9e\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"480\" height=\"341\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig04_rockblockslide3.jpg\" class=\"attachment-large size-large wp-image-2513\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig04_rockblockslide3.jpg 480w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig04_rockblockslide3-300x213.jpg 300w\" sizes=\"(max-width: 480px) 100vw, 480px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 4: Oblique aerial photograph of the landslide toe (from Slosson and al., 1992)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-ab246b9 elementor-widget elementor-widget-image\" data-id=\"ab246b9\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"612\" height=\"417\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig05_rockblockslide2.jpg\" class=\"attachment-large size-large wp-image-2518\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig05_rockblockslide2.jpg 612w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig05_rockblockslide2-300x204.jpg 300w\" sizes=\"(max-width: 612px) 100vw, 612px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 5: Photograph showing cracks in ground surface on second main landslide block (from Slosson and al., 1992)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-1b53ccb elementor-widget elementor-widget-image\" data-id=\"1b53ccb\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"492\" height=\"335\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig06_glissementroute.jpg\" class=\"attachment-large size-large wp-image-2523\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig06_glissementroute.jpg 492w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig06_glissementroute-300x204.jpg 300w\" sizes=\"(max-width: 492px) 100vw, 492px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 6: Road cut off by a translational slide in Merlas, Is\u00e8re, France, on June 6 2004 (from www.irma-grenoble.com)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-ed53705 elementor-widget elementor-widget-image\" data-id=\"ed53705\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"487\" height=\"329\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig07_glissementRN.jpg\" class=\"attachment-large size-large wp-image-2528\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig07_glissementRN.jpg 487w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig07_glissementRN-300x203.jpg 300w\" sizes=\"(max-width: 487px) 100vw, 487px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 7: Translational slide in a highway slope, Voiron, Is\u00e8re, France, on November 18 2002 (from www.irma-grenoble.com)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-ca3307c elementor-widget elementor-widget-image\" data-id=\"ca3307c\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"575\" height=\"268\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig08_Rotational_Landslide_VilniusLithuania.jpg\" class=\"attachment-large size-large wp-image-2533\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig08_Rotational_Landslide_VilniusLithuania.jpg 575w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig08_Rotational_Landslide_VilniusLithuania-300x140.jpg 300w\" sizes=\"(max-width: 575px) 100vw, 575px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 8: Building damaged by a rotational slide in Vilnius, Lithuania (from Malet, 2003)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-0e8dce1 elementor-widget elementor-widget-image\" data-id=\"0e8dce1\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"364\" height=\"541\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig09_LACONCHITA.jpg\" class=\"attachment-large size-large wp-image-2538\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig09_LACONCHITA.jpg 364w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig09_LACONCHITA-202x300.jpg 202w\" sizes=\"(max-width: 364px) 100vw, 364px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 9: Houses damaged by the rotational slide of La Conchita, Californie, USA (from Malet, 2003)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-5d3a0c2 elementor-widget elementor-widget-image\" data-id=\"5d3a0c2\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"498\" height=\"307\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig10_camion.jpg\" class=\"attachment-large size-large wp-image-2543\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig10_camion.jpg 498w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig10_camion-300x185.jpg 300w\" sizes=\"(max-width: 498px) 100vw, 498px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 10: Truck knocked down by a slide in front of a residential area, France (from MATE, METL, 1999)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-7f3c242 elementor-widget elementor-widget-image\" data-id=\"7f3c242\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"585\" height=\"394\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig11_EarthFlowPanaro68.jpg\" class=\"attachment-large size-large wp-image-2548\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig11_EarthFlowPanaro68.jpg 585w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/fig11_EarthFlowPanaro68-300x202.jpg 300w\" sizes=\"(max-width: 585px) 100vw, 585px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 11: Bridge destroyed by an earth flow in 1968 in the River Panaro valley (photo by M. Pellegrini)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-9949c51 elementor-widget elementor-widget-text-editor\" data-id=\"9949c51\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><strong style=\"font-size: 1rem; text-align: left;\">References:<\/strong><\/p><p>LEONE F., ASTE JP., LEROI E., 1996. Vulnerability assessment of elements exposed to mass movements: working toward a better risk perception. In: Senesset K (Ed): Landslides, Proceedings of the 7th International Symposium on landslides, Balkema, Rotterdam<br \/>MALET J.P. Les \u00ab glissement de type \u00e9coulement \u00bb dans les marnes noires des Alpes du sud. Morphologie, fonctionnement et mod\u00e9lisation hydrom\u00e9canique. PhD Thesis: Institut de Physique du Globe, Universit\u00e9 Louis Pasteur de Strasbourg, 2003. 353 p.<br \/>MATE, METL, 1999. Plans de pr\u00e9vention des risques naturels pr\u00e9visibles (PPR) : Risques de mouvements de terrain. Guide g\u00e9n\u00e9ral. La Documentation fran\u00e7aise, Paris, 71 p.<br \/>SLOSSON E., KEENE A.G., JOHNSON J.A., 1992. Landslides\/Landslide mitigation. In: Reviews of Engineering Geology, Volume IX, Colorado<\/p><p><strong>Websites:<\/strong><br \/><a href=\"http:\/\/www.irma-grenoble.com\/\" target=\"_blank\" rel=\"noopener\">www.irma-grenoble.com<\/a><br \/><a href=\"http:\/\/www.prim.net\/\" target=\"_blank\" rel=\"noopener\">www.prim.net<\/a><\/p><p>Go to 5. What could be the consequences of LANDSLIDES?<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-1754\" class=\"elementor-tab-title\" data-tab=\"4\" role=\"tab\" aria-controls=\"elementor-tab-content-1754\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">5.1.4 Details on consequences of the fall process<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-1754\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"4\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-1754\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"2554\" class=\"elementor elementor-2554\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-c153496 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"c153496\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-a015937\" data-id=\"a015937\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-b241080 elementor-widget elementor-widget-text-editor\" data-id=\"b241080\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Because of their sudden and (in many cases) unpredictable nature, fall events can be very dangerous for the infrastructures and the population.<\/p><p>Damages extent depends on energy of the falling material (function of weight and velocity). Rock falls can damage housing, interrupt roadway systems and cause human losses.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-9b635d4 elementor-widget elementor-widget-image\" data-id=\"9b635d4\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"333\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/1_fallImpacts-1024x333.jpg\" class=\"attachment-large size-large wp-image-2556\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/1_fallImpacts-1024x333.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/1_fallImpacts-300x98.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/1_fallImpacts-768x250.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/1_fallImpacts.jpg 1217w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 1: Different effects of a fall event on a house (modified from L\u00e9one and al., 1996)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-9d23880 elementor-widget elementor-widget-image\" data-id=\"9d23880\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"407\" height=\"548\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_rockfallhouse.jpg\" class=\"attachment-large size-large wp-image-2562\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_rockfallhouse.jpg 407w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_rockfallhouse-223x300.jpg 223w\" sizes=\"(max-width: 407px) 100vw, 407px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 2: House damaged by a block fall, Norway (from www.ngi.no)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-245ac04 elementor-widget elementor-widget-image\" data-id=\"245ac04\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"465\" height=\"340\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/3_rockfallhouse2.jpg\" class=\"attachment-large size-large wp-image-2567\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/3_rockfallhouse2.jpg 465w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/3_rockfallhouse2-300x219.jpg 300w\" sizes=\"(max-width: 465px) 100vw, 465px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 3: Buildings on the train station quay damaged by Aigueblanche rockfall, Savoie, France, in 1977 (from Besson, 2005)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-4ffce2f elementor-widget elementor-widget-image\" data-id=\"4ffce2f\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"493\" height=\"334\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/4_rockfall-house3_irma.jpg\" class=\"attachment-large size-large wp-image-2572\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/4_rockfall-house3_irma.jpg 493w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/4_rockfall-house3_irma-300x203.jpg 300w\" sizes=\"(max-width: 493px) 100vw, 493px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 4: House and car damaged by a 30 ton block fallen in Lumbin, Is\u00e8re, France, on January 2 2002 (from www.irma-grenoble.com)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-265bb26 elementor-widget elementor-widget-image\" data-id=\"265bb26\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"494\" height=\"330\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/5_rockfallroadirma.jpg\" class=\"attachment-large size-large wp-image-2577\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/5_rockfallroadirma.jpg 494w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/5_rockfallroadirma-300x200.jpg 300w\" sizes=\"(max-width: 494px) 100vw, 494px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 5: Road damaged by a 2000 m3 rock fall, Saint-Quentin-sur-Is\u00e8re, France (from www.irma-grenoble.com)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-ddc8052 elementor-widget elementor-widget-image\" data-id=\"ddc8052\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"491\" height=\"315\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/6_rockfall-road2_irma.jpg\" class=\"attachment-large size-large wp-image-2582\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/6_rockfall-road2_irma.jpg 491w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/6_rockfall-road2_irma-300x192.jpg 300w\" sizes=\"(max-width: 491px) 100vw, 491px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 6: Road damaged by a rock fall, Laffrey, Is\u00e8re, France (from www.irma-grenoble.com)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-db48bb5 elementor-widget elementor-widget-image\" data-id=\"db48bb5\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"244\" height=\"169\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/7_choranche2.jpg\" class=\"attachment-large size-large wp-image-2587\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 7: Rock fall near Choranche, Is\u00e8re, France, on January 31 2004: 2000 m3 rock falled on a departmental road. A car has been ran down, the two passengers have been killed (from www.geolithe.com)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-94a38be elementor-widget elementor-widget-image\" data-id=\"94a38be\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"389\" height=\"294\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/8_choranche.jpg\" class=\"attachment-large size-large wp-image-2592\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/8_choranche.jpg 389w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/8_choranche-300x227.jpg 300w\" sizes=\"(max-width: 389px) 100vw, 389px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 8: Rock fall on the same road than in fig. 15, on November 2 2007 : 5 m3 rock landed on a car and killed two of the five passengers of the vehicle (from rhone-alpes-auvergne.france3.fr)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-85055a0 elementor-widget elementor-widget-text-editor\" data-id=\"85055a0\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p style=\"text-align: center;\"><em style=\"font-size: 1rem; text-align: left;\">Fig. 9: Car damaged by a rock fall at Upper Island Cove, Canada, on February 14 1999. A 8 ton block toppled from the top of a 100 m slope, ran roughly 150 m, struck a house, and landed on the top of a car parked beside the house (from\u00a0<a href=\"http:\/\/www.heritage.nf.ca\/\" target=\"_blank\" rel=\"noopener\">www.heritage.nf.ca<\/a>)<\/em><\/p><p>Constructive layouts exist to protect housing, such as reinforcement of the exposed fa\u00e7ade or the roof. But the best way is to avoid building in vulnerable areas and to use protection techniques.<\/p><p>Consequences of the rockfall avalanche process<\/p><p>Rock fall avalanches are incredibly destructive, they move with great rapidity and obliterate everything in their path. Perhaps the most important, once an event has occurred, is to discover whether the avalanche has dammed the valley. If it has, and a lake has formed, maximum effort must be given to take control of the breaching dam, because the resulting flow may cause a second disaster.<\/p><p>Consequences of the topple process<\/p><p>Topples are potentially very dangerous because they develop at first by loading, then by progressive basal failure and rotation, and eventually sudden collapse. This failure is dramatic, the break-up spectacular and the velocity of loose boulders and run-out high.<\/p><p>Damages on the infrastructures and population are the same than concerning fall risk (see details on fall).<\/p><p><strong>References:<\/strong><br \/>BESSON L., 2005. Les risques naturels: de la connaissance pratique \u00e0 la gestion administrative. Editions Techni. Cit\u00e9s, Voiron, 60 p.<br \/>LEONE F., ASTE JP., LEROI E., 1996. Vulnerability assessment of elements exposed to mass movements: working toward a better risk perception. In: Senesset K (Ed): Landslides, Proceedings of the 7th International Symposium on landslides, Balkema, Rotterdam<\/p><p><strong>Websites:<\/strong><br \/><a href=\"http:\/\/www.irma-grenoble.com\/\" target=\"_blank\" rel=\"noopener\">www.irma-grenoble.com<\/a><br \/><a href=\"http:\/\/www.prim.net\/\" target=\"_blank\" rel=\"noopener\">www.prim.net<\/a><\/p><p>Go to 5. What could be the consequences of LANDSLIDES?<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-1755\" class=\"elementor-tab-title\" data-tab=\"5\" role=\"tab\" aria-controls=\"elementor-tab-content-1755\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">5.1.5 Consequences of the flow process<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-1755\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"5\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-1755\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"2598\" class=\"elementor elementor-2598\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-b774a01 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"b774a01\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-9e9c894\" data-id=\"9e9c894\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-fe930fe elementor-widget elementor-widget-text-editor\" data-id=\"fe930fe\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>The damages caused by a flow event depend on the quantity of material (debris, soil, mud) displaced. In the deposit areas, flows develop successive lobes and can spread on considerable surfaces. These are rapid phenomenon, thus they can be very dangerous for the infrastructures and the population. The socio-economic impact and the loss of life, property and agriculture can be catastrophic in the case of large flows through populated areas. In the case of channelized flows (debris flows), material often overflows the banks and interrupts roadway systems. The deposits are also responsible for severe indirect damages and hazards such as damming of rivers or sudden debris supply to river systems.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-570a4c8 elementor-widget elementor-widget-image\" data-id=\"570a4c8\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"299\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/1_Flows_Impacts-1024x299.jpg\" class=\"attachment-large size-large wp-image-2602\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/1_Flows_Impacts-1024x299.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/1_Flows_Impacts-300x88.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/1_Flows_Impacts-768x224.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/1_Flows_Impacts.jpg 1244w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 1: Different effects of a flow event on a house (modified from L\u00e9one and al., 1996)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-53a8d75 elementor-widget elementor-widget-image\" data-id=\"53a8d75\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"768\" height=\"1148\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_Schlans_DebrisFlow-768x1148.jpg\" class=\"attachment-medium_large size-medium_large wp-image-2607\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_Schlans_DebrisFlow-768x1148.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_Schlans_DebrisFlow-201x300.jpg 201w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_Schlans_DebrisFlow-685x1024.jpg 685w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_Schlans_DebrisFlow-1027x1536.jpg 1027w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_Schlans_DebrisFlow-1370x2048.jpg 1370w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_Schlans_DebrisFlow-scaled.jpg 1712w\" sizes=\"(max-width: 768px) 100vw, 768px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 2: Debris flows at Schlans, Switzerland, in 2000 caused the destruction of a part of the village and the death of about 10 people (from Rema\u00eetre, 2006)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-458cd49 elementor-widget elementor-widget-image\" data-id=\"458cd49\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"254\" height=\"337\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/3_gondo_remaitre.jpg\" class=\"attachment-large size-large wp-image-2612\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/3_gondo_remaitre.jpg 254w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/3_gondo_remaitre-226x300.jpg 226w\" sizes=\"(max-width: 254px) 100vw, 254px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 3: Mudflow at Gondo, Switzerland, in 2000. About 10 people were killed (from Rema\u00eetre, 2006)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-85739a7 elementor-widget elementor-widget-image\" data-id=\"85739a7\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"416\" height=\"308\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/4_tasch_ancey.jpg\" class=\"attachment-large size-large wp-image-2617\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/4_tasch_ancey.jpg 416w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/4_tasch_ancey-300x222.jpg 300w\" sizes=\"(max-width: 416px) 100vw, 416px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 4: The village of T\u00e4sch, Switzerland, damaged by a debris flow in June 2001 (from Ancey, 2007)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-99ab692 elementor-widget elementor-widget-image\" data-id=\"99ab692\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"576\" height=\"390\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/5_DebrisFlowTrack_SanMateo_California.jpg\" class=\"attachment-large size-large wp-image-2622\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/5_DebrisFlowTrack_SanMateo_California.jpg 576w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/5_DebrisFlowTrack_SanMateo_California-300x203.jpg 300w\" sizes=\"(max-width: 576px) 100vw, 576px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 5: Houses damaged by a debris flow at San Mat\u00e9o, California (from Cannon et Ellen, 1985)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-e09da6a elementor-widget elementor-widget-image\" data-id=\"e09da6a\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"576\" height=\"428\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/6_DebrisFlow_USGS.jpg\" class=\"attachment-large size-large wp-image-2628\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/6_DebrisFlow_USGS.jpg 576w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/6_DebrisFlow_USGS-300x223.jpg 300w\" sizes=\"(max-width: 576px) 100vw, 576px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 6: House damaged by a debris flow (from USG)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-a34f326 elementor-widget elementor-widget-image\" data-id=\"a34f326\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"288\" height=\"189\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/7_hashi_remaitre.jpg\" class=\"attachment-large size-large wp-image-2638\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 7: Road cut off by a debris flow at Hashi, Japan, in 2004 (from Rema\u00eetre, 2006)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-03202de elementor-widget elementor-widget-image\" data-id=\"03202de\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"768\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/8_stage-DDAF-90-1024x768.jpg\" class=\"attachment-large size-large wp-image-2633\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/8_stage-DDAF-90-1024x768.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/8_stage-DDAF-90-300x225.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/8_stage-DDAF-90-768x576.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/8_stage-DDAF-90-1536x1152.jpg 1536w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/8_stage-DDAF-90.jpg 2048w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 8: Bridge destroyed by a debris flow occurred in the Pisse torrent, in Reallon, Hautes-Alpes, France, on June 18 2005 (photo by Arnaud)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-d35fa61 elementor-widget elementor-widget-image\" data-id=\"d35fa61\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"498\" height=\"354\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/9_faucon96.jpg\" class=\"attachment-large size-large wp-image-2643\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/9_faucon96.jpg 498w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/9_faucon96-300x213.jpg 300w\" sizes=\"(max-width: 498px) 100vw, 498px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 9: Bridge and road damaged by a debris flow occurred in the Faucon torrent, in the Barcelonnette Basin, France, on August 19 1996. Debris overflowed 50 cm above the bridge. At the confluence with the Ubaye river, 2 to 4 m-thick debris spread up to a width of 250 m (from Sivan, 2000)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-18b2d88 elementor-widget elementor-widget-image\" data-id=\"18b2d88\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"274\" height=\"182\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/10_faucon-2003.jpg\" class=\"attachment-large size-large wp-image-2649\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 10: House damaged by a debris flow also occurred in the Faucon torrent, in the Barcelonnette Basin, France, on August 5 2003. The road and the bridge were cut off again, and six houses were damaged (photo by Peyron)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-4376603 elementor-widget elementor-widget-image\" data-id=\"4376603\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"291\" height=\"199\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/11_angra-dos-reis_remaitre.jpg\" class=\"attachment-large size-large wp-image-2654\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 11: Inhabitants of Angra dos Reis, Brazil, during a mudflow in 2002 (from Rema\u00eetre, 2006)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-49407c1 elementor-widget elementor-widget-image\" data-id=\"49407c1\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"505\" height=\"343\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/12_schields-canyon.jpg\" class=\"attachment-large size-large wp-image-2659\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/12_schields-canyon.jpg 505w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/12_schields-canyon-300x204.jpg 300w\" sizes=\"(max-width: 505px) 100vw, 505px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 12: Effects of a debris flows in Shields Canyon, California, February 1978 (from Slosson and al., 1992)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-2575c08 elementor-widget elementor-widget-text-editor\" data-id=\"2575c08\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><strong style=\"font-size: 1rem; text-align: left;\">References:<\/strong><\/p><p>ANCEY C., 2007. Notes de cours &#8211; Risques hydrologiques et am\u00e9nagement du territoire. Laboratoire hydraulique environnementale, \u00c9cole Polytechnique F\u00e9d\u00e9rale de Lausanne<br \/>LEONE F., ASTE JP., LEROI E., 1996. Vulnerability assessment of elements exposed to mass movements: working toward a better risk perception. In: Senesset K (Ed): Landslides, Proceedings of the 7th International Symposium on landslides, Balkema, Rotterdam<br \/>REMAITRE A., 2006. Morphologie et dynamique des laves torrentielles : Applications aux torrents des Terres Noires du bassin de Barcelonnette (Alpes du Sud). PhD Thesis: Laboratoire Geophen, Universit\u00e9 de Caen\/Basse-Normandie, 487 p.<br \/>SLOSSON E., KEENE A.G., JOHNSON J.A., 1992. Landslides\/Landslide mitigation. In: Reviews of Engineering Geology, Volume IX, Colorado<\/p><p><strong>Websites:<\/strong><br \/><a href=\"http:\/\/www.irma-grenoble.com\/\" target=\"_blank\" rel=\"noopener\">www.irma-grenoble.com<\/a><br \/><a href=\"http:\/\/www.prim.net\/\" target=\"_blank\" rel=\"noopener\">www.prim.net<\/a><\/p><p>Go to 5. What could be the consequences of LANDSLIDES?<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p>\n<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-2086\" class=\"elementor-tab-title\" data-tab=\"6\" role=\"tab\" aria-controls=\"elementor-tab-content-2086\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">6. Les causes des glissements de terrain peuvent-elles \u00eatre influenc\u00e9es par le comportement humain ?<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-2086\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"6\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-2086\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"7929\" class=\"elementor elementor-7929 elementor-2665\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-ceb7fff elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"ceb7fff\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-0e21c04\" data-id=\"0e21c04\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-ef80194 elementor-widget elementor-widget-text-editor\" data-id=\"ef80194\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Les activit\u00e9s humaines (terrassement, vibration, d\u00e9forestation, exploitation de mat\u00e9riaux ou de nappe phr\u00e9atique, excavation, construction routi\u00e8re, exploitation mini\u00e8re, carri\u00e8re, travaux de chargement, etc.) peuvent influencer le d\u00e9clenchement de mouvements de terrain, en agissant comme des causes externes.<\/p>\n<p>On parle d\u2019effondrement (affaissement rapide du sol) lorsque le sol se d\u00e9robe brutalement, produisant un aven (ou une doline) d\u2019effondrement ou un puits de plus ou moins grandes dimensions (diam\u00e8tre de quelques m\u00e8tres \u00e0 plusieurs hectares et profondeur de quelques m\u00e8tres \u00e0 plusieurs centaines de m\u00e8tres). Un ph\u00e9nom\u00e8ne de subsidence progressive (affaissement lent) peut pr\u00e9c\u00e9der un effondrement.<\/p>\n<p>Les \u00e9pisodes d\u2019effondrement se produisent g\u00e9n\u00e9ralement au-dessus de cavit\u00e9s creus\u00e9es par l\u2019homme (tunnels, puits, carri\u00e8res souterraines recouvertes ou mines \u2013\u00a0de fer, de sel, de charbon, etc.)<\/p>\n<p>Ils sont \u00e9galement fr\u00e9quents dans les terrains karstiques, o\u00f9 la dissolution du calcaire par l\u2019eau sous la surface cr\u00e9e des cavit\u00e9s naturelles (des grottes par exemple). Si le toit de la cavit\u00e9 devient trop fragile, il peut s\u2019effondrer, emportant roche et terre dans sa chute et cr\u00e9ant un effondrement en surface.<\/p>\n<p>Les effondrements peuvent faire de nombreuses victimes dans les zones habit\u00e9es\u00a0: en 1958, \u00e0 Roosburg (Belgique), 18\u00a0personnes sont mortes \u00e0 la suite de l\u2019effondrement d\u2019un tunnel\u00a0; en 1961, \u00e0 Clamart et \u00e0 Issy-les-Moulineaux (France), 21\u00a0personnes ont p\u00e9ri lors de l\u2019effondrement d\u2019une ancienne carri\u00e8re souterraine.<\/p>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-223360b elementor-widget elementor-widget-image\" data-id=\"223360b\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"795\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/SinkholeGuatemalaCitynew-1024x795.jpg\" class=\"attachment-large size-large wp-image-2667\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/SinkholeGuatemalaCitynew-1024x795.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/SinkholeGuatemalaCitynew-300x233.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/SinkholeGuatemalaCitynew-768x596.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/SinkholeGuatemalaCitynew.jpg 1521w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Doline d\u2019effondrement g\u00e9ante apparue le dimanche 30 mai 2010 en plein centre de Guatemala, engloutissant un immeuble de trois \u00e9tages.<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-3b0fb8a elementor-widget elementor-widget-text-editor\" data-id=\"3b0fb8a\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Selon S. Bonis, g\u00e9ologue au Dartmouth College (New Hampshire, \u00c9tats-Unis) vivant actuellement \u00e0 Guatemala, l\u2019activit\u00e9 humaine, et non naturelle, est probablement responsable de l\u2019effondrement de cette doline g\u00e9ante\u00a0: une rupture dans une conduite d\u2019\u00e9gout ou d\u2019eau pluviale a sans doute creus\u00e9 le sous-sol, ce qui a permis la formation du gouffre. Cette doline, estim\u00e9e \u00e0 18\u00a0m\u00e8tres en largeur et 100 m\u00e8tres en profondeur, semble s\u2019\u00eatre effondr\u00e9e \u00e0 la suite du passage diluvien de la temp\u00eate Agatha. Mais la cavit\u00e9 s\u2019est form\u00e9e \u00e0 l\u2019origine parce que la ville et ses infrastructures souterraines reposent sur une couche de plusieurs centaines de m\u00e8tres de pierres ponces, d\u00e9pos\u00e9es par les \u00e9ruptions volcaniques pass\u00e9es. Dans la ville de Guatemala, ces pierres ponces ne se sont pas encore consolid\u00e9es (en une roche indur\u00e9e). Elles s\u2019effritent donc rapidement, notamment sous l\u2019effet d\u2019un d\u00e9bit d\u2019eau rapide. Les r\u00e8gles de zonage et les codes d\u2019urbanisme sont en g\u00e9n\u00e9ral assez laxistes \u00e0 Guatemala, selon Bonis, et les quelques normes existantes sont rarement respect\u00e9es. Par cons\u00e9quent, des canalisations ont pu fuir pendant suffisamment longtemps pour cr\u00e9er les conditions favorables \u00e0 la formation d\u2019une doline. Celle-ci partage des similarit\u00e9s frappantes avec une autre apparue dans la m\u00eame ville en 2007\u00a0: toutes deux, tr\u00e8s similaires en apparence, se sont effondr\u00e9es dans le m\u00eame quartier. Il faut y voir plus qu\u2019une co\u00efncidence, surtout si les conduites d\u00e9faillantes associ\u00e9es \u00e0 la doline de 2010 m\u00e8nent \u00e0 des conduites proches de celle de 2007.<\/p>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-4236516 elementor-widget elementor-widget-accordion\" data-id=\"4236516\" data-element_type=\"widget\" data-widget_type=\"accordion.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<div class=\"elementor-accordion\" role=\"tablist\">\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-6941\" class=\"elementor-tab-title\" data-tab=\"1\" role=\"tab\" aria-controls=\"elementor-tab-content-6941\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">6.1. More information on human behaviour which can influence the landslides causes<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-6941\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"1\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-6941\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"2674\" class=\"elementor elementor-2674\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-00128ec elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"00128ec\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-05de79b\" data-id=\"05de79b\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-8fc73ef elementor-widget elementor-widget-text-editor\" data-id=\"8fc73ef\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Man transforms, corrects and modifies natural processes by increasing or decreasing their rate of action and by causing the rupture of certain equilibria which Nature will try to reconstitute in different ways. With the passing of time this modifying action has assumed increasingly widespread and intense patterns.<\/p><p>Actually, besides high-magnitude mass movements which occur quite seldom, there is a huge number of medium to small sized landslides which are so widespread that the related cost for human society is even higher than that of catastrophic events. Increasing losses due to low-magnitude, high-frequency events are fostered by human activity which tends to increase landslide hazard and favours vulnerability situations.<\/p><p>Man-made processes, can influence the triggering of mass movements acting on the landslides external causes.<\/p><p>As regards external causes, which result in an increase of shear stresses, those processes giving rise to changes in slope geometry, mainly with an increase of the gradient, should be considered. Among these processes the following due to the human activity are particularly important: excavation, road construction, mining and quarrying, exploitation of materials or water tables overloading, deforestation, terracing etc.<\/p><p>In particular, human activity in the vicinity of a slope may increase the forces tending to cause failure.<br \/>Human induced modifications thay may adversely affect external loads are: i) grading of the existing slope or of adjacent slopes; ii) adjacent construction; iii) construction blast damage; iv) vibrations of passing vehicles.<\/p><p>Slope re-garding may result in a condition similar to that caused by natural erosion and deposition in which the toe become s oversteep or material is accumulated on the crest. Costruction adjacent to the crest of a slope can surcharge a slope. Grading adjacent to a slope can consist of excavation or filling; excavation would create oversteepened slopes, whereas filling would create a surcharge. These conditions should be anticipated or prevented so that an appropriate stability analysis can be made.<\/p><p>Excavation blasting can cause excessive fracturing of otherwise intact rock material. Improper blasting loosens the rocks, decreases the density and strength, and increases the permeabilit\u00e0. These conditions should be recognized in the field so that slope remediation can be carried out durino or immediately after construction.<\/p><p>Most vibrations of passing vehicles impose small loads on adjacent slopes, but some vibrations can influente slope stability. For instance, a freight train moving on tracks a shortb distance from a steep slope with with shallow groundwater may induce vibrations at a frequency and amplitude that could cause permanent deformation or failure of the slope.<\/p><p>Some examples of human activity, which influenced the triggering of landslides are found in the River Panaro valley (Modena Apennines).<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-29acb50 elementor-widget elementor-widget-image\" data-id=\"29acb50\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"766\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_1_cavaRoncobotto-1024x766.jpg\" class=\"attachment-large size-large wp-image-2677\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_1_cavaRoncobotto-1024x766.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_1_cavaRoncobotto-300x225.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_1_cavaRoncobotto-768x575.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_1_cavaRoncobotto-1536x1150.jpg 1536w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_1_cavaRoncobotto.jpg 1578w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 1: Earth slides in clay formation due to exploitation of the Roncobotto quarry (photo by D. Castaldini)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-7dad155 elementor-widget elementor-widget-image\" data-id=\"7dad155\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"766\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_2_DSCN3081Ca-1024x766.jpg\" class=\"attachment-large size-large wp-image-2682\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_2_DSCN3081Ca-1024x766.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_2_DSCN3081Ca-300x224.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_2_DSCN3081Ca-768x575.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_2_DSCN3081Ca-1536x1149.jpg 1536w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_2_DSCN3081Ca-2048x1532.jpg 2048w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 2: The cutting of the slope for the construction of the \u201cAl Boschetto Restaurant\u201d (on the left), reactived a dormant landslide. The construction of a retaining wall was not sufficient as protection measure. Therefore a new retaining wall with an anchor system has been built in 2007 (photo by D. Castaldini)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-cc87d20 elementor-widget elementor-widget-text-editor\" data-id=\"cc87d20\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">The Ca\u2019 Bonettini landslide body (Fig. 3 and 4) resumed movement on 15th September 2003, just a few hours after a M 5.0 seismic shock .<\/span><\/p><p>Considering the distance of the landslide from the epicentre (35 km away in the Bologna Apennines) and the fact that locally the quake was not felt by the population but was recorded only at an instrument level, it is unlikely that a low-energy shock might be considered as the main, intrinsic cause of landslide reactivation.<\/p><p>Field observations, subsurface investigations and laboratory tests seem to indicate that the predisposing causes of the Ca\u2019 Bonettini landslide could be found in the deep shrinkage fissures that dismembered the whole clayey slope as a consequence of a 3.5-month long summer drought, with a progressive decline of shear strength parameters. In addition, another important factor in further reducing stability was identified in major construction works at the foot of the landslide body, with the removal of large amounts of earth. These works were carried out without considering that the area chosen for industrial development corresponded to the foot of a dormant landslide. Therefore, the 14th September 2003 low-intensity quake was only the triggering cause of a slope movement which would have probably started all the same a few days or weeks later, as the removal of soil from the landslide foot continued as planned.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-a2eb1df elementor-widget elementor-widget-image\" data-id=\"a2eb1df\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"526\" height=\"394\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_3CaBonett.jpg\" class=\"attachment-large size-large wp-image-2688\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_3CaBonett.jpg 526w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_3CaBonett-300x225.jpg 300w\" sizes=\"(max-width: 526px) 100vw, 526px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 3 Ca\u2019 Bonettini landslide. The industrial settlement is located at the foot of a landslide (photo by D. Castaldini)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-5b9f5d9 elementor-widget elementor-widget-image\" data-id=\"5b9f5d9\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"766\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_4CaBonett-1024x766.jpg\" class=\"attachment-large size-large wp-image-2693\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_4CaBonett-1024x766.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_4CaBonett-300x224.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_4CaBonett-768x575.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_4CaBonett-1536x1149.jpg 1536w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_4CaBonett-2048x1532.jpg 2048w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 4. Detail of the crown of the Ca\u2019 Bonettini landslide (photo by D. Castaldini)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-020d4b8 elementor-widget elementor-widget-text-editor\" data-id=\"020d4b8\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">Rapid subsidence is a brutal spontaneous collapse producing sinkholes or shafts of a more or less large extent (diameter of a few meters to several hectares) and a variable depth (a few meters to many hundreds of meters). Rapid subsidence can occur after a progressive subsidence.<\/span><\/p><p>Commonly, rapid subsidence occurs above man-made voids, such as tunnels, wells and covered subterranean quarries or mines (iron, salt, coal, etc.) It is also frequent in karst terrains, where dissolution of limestone by fluid flow in the subsurface causes the creation of voids (i.e. caves). If the roof of these voids becomes too weak, it can collapse and the overlying rock and earth will fall into the space, causing subsidence at the surface.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-def24d4 elementor-widget elementor-widget-image\" data-id=\"def24d4\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"394\" height=\"264\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_5_fontispaysauge.jpg\" class=\"attachment-large size-large wp-image-2699\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_5_fontispaysauge.jpg 394w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_5_fontispaysauge-300x201.jpg 300w\" sizes=\"(max-width: 394px) 100vw, 394px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 5 Roof collapsing above subterranean caves in limestone, Pays d\u2019Auge, Normandy, France (Photo : O. Maquaire, Cerg)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-769a4c0 elementor-widget elementor-widget-text-editor\" data-id=\"769a4c0\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">In urban zones, rapid subsidence can cause numerous victims. A well known disaster occurred in 1958 in Roosburg (Belgium) when 18 people were killed by a tunnel collapse of an ancient subterranean quarry. In Clamart and Issy-les-Moulineaux (France), 21 people died as an ancient subterranean quarry collapsed in 1961.<\/span><\/p><p>A large sinkhole was produced by a major rock collapse on 10 february 1989 at Utsunomiya City (Japan)(Sassa1999). The plan shape of the initial sinkhole was elliptical with a length of 70 m and with of 60 m; the original ground surface (Fig.6). A factory of a building stone company collapsed into the sinkhole without casualties, fortunately, as the factory was unoccupied at that time.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-ace4136 elementor-widget elementor-widget-image\" data-id=\"ace4136\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"654\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_6Utsonomiya-collapse1-1024x654.jpg\" class=\"attachment-large size-large wp-image-2705\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_6Utsonomiya-collapse1-1024x654.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_6Utsonomiya-collapse1-300x192.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_6Utsonomiya-collapse1-768x491.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_6Utsonomiya-collapse1-1536x981.jpg 1536w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_6Utsonomiya-collapse1.jpg 1684w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig.6. The first subsidence at Utsunomiya City on 10 february 1989 (Photo by Sassa, 1999)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-bd60cb2 elementor-widget elementor-widget-text-editor\" data-id=\"bd60cb2\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">A second collapse, which enlarged the the first sinkhole, took place on 5 march 1989 (Fig.7). Its plane shape become lenticular (140 m in the NS direction and 90 m in the EW direction) and its area reached 10,000 m2. The depth of the sinkhole was about 30 m and the hole volume was estimated at 300,000 m3. A third failure occurred on 18 march 1989. It was 30 m long and 15 m wide along the western rim of the 2nd collapse.<\/span><\/p><p>The movement of the first collapse was largely a vertical fall or rapid subsidence. That of the second one was a combination of sinking and sliding in the northern part and sinking in the eastern part. The third one looks like a slump.<br \/>The sinkhole area is one of several important areas of stone production for building material in the Kanto region. Stone is cut in underground quarries from a Miocene Tuff formation. The tuff has been used as building material since the 8th century. The typical mining method utilizes rooms up to 10 m wide. 100 m long and 15 m high. The rooms are separated by pillars. It is not known if the the initial collapse involved a pillar failure or roof caving. People living near the sinkhole had heard sounds of low frequency for two months before the first collapse. However no cracks or deformation were recognized the ground surface. After the first collapse, many cracks were observed at the ground surface near the hole.<br \/>Important factors causing the collapse could be: I) shallow depth of the quarries (less than 40 m); ii) presence of two levels of underground workings at shallow depth over a wide area.<\/p><p>Since 1959, similar sinkholes due to rock collapse have occurred at least twenty time in that area as result of the underground quarrying (3 persons have been killed).<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-b72827d elementor-widget elementor-widget-image\" data-id=\"b72827d\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"654\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_7Utsonomiya-collapse2-1024x654.jpg\" class=\"attachment-large size-large wp-image-2710\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_7Utsonomiya-collapse2-1024x654.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_7Utsonomiya-collapse2-300x192.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_7Utsonomiya-collapse2-768x491.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_7Utsonomiya-collapse2-1536x981.jpg 1536w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Fig_7Utsonomiya-collapse2.jpg 1684w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig.7. The second collapse at Utsunomiya City on 5 march 1989 (Photo by Sassa, 1999)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-ab5329a elementor-widget elementor-widget-text-editor\" data-id=\"ab5329a\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><strong style=\"font-size: 1rem; text-align: left;\">References<\/strong><\/p><p>Embleton, C., and Embleton C. (eds.) (1997), Geomorphological Hazards of Europe. Developments in Earth Surface Processes 5. Amsterdam : Elsevier, 524p.<br \/>Flageollet, J. C. (1988), Les mouvements de terrain et leur pr\u00e9vention, Paris : Masson, 224p.<br \/>Maquaire, O., (2005). Geomorphic hazards and natural risks, In: Koster, E., A. (ed.), The Physical Geography of Western Europe, Oxford Regional Environments, Oxford University Press, Chapter 18, 354-377.<br \/>Sassa K. (Ed.), 1999. landslides of the world. Kyoto University Press. 413, pp<br \/>Tosatti G. (2004) \u2013Frane del bacino del Panaro correlabili ad eventi sismici. In Mordini A. &amp; Pellegrini M. (a cura di) \u2013 Contributi per la conoscenza delle frane dell\u2019Appennino Modenese. Rassegna Frignanese, n.33 (2003), Tip. Benedetti. Pavullo nel Frignano, 119-136.<br \/>Tosatti G., Castaldini D, Barbieri M., D&rsquo;amato-Avanzi G., Giannecchini R., Mandrone G., Pellegrini M., Perego S., Puccinelli A., Romeo R.W., &amp; Tellini C. (2008 &#8211; Factors of seismically-related landslides in the Northern Apennines, Italy. Revista de geomorfologie.<br \/>Turner A.K. and Schuster R.L. (Ed.s), 1996. Landslides. Investigation and Mitigation. Special Report 247. National Academy Press, Washington D.C., 673 pp.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p>\n<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-2087\" class=\"elementor-tab-title\" data-tab=\"7\" role=\"tab\" aria-controls=\"elementor-tab-content-2087\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">7. Les cons\u00e9quences des glissements de terrain peuvent-elles \u00eatre influenc\u00e9es par le comportement humain ?<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-2087\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"7\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-2087\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"7931\" class=\"elementor elementor-7931 elementor-2716\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-86c22b9 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"86c22b9\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-e258b05\" data-id=\"e258b05\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-e832425 elementor-widget elementor-widget-text-editor\" data-id=\"e832425\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>L\u2019homme a la capacit\u00e9 d\u2019influencer les cons\u00e9quences des glissements de terrain en r\u00e9pondant au \u00ab\u00a0quand\u00a0?\u00a0\u00bb, au \u00ab\u00a0pourquoi\u00a0?\u00a0\u00bb et au \u00ab\u00a0o\u00f9\u00a0?\u00a0\u00bb de ce ph\u00e9nom\u00e8ne et en proc\u00e9dant \u00e0 une planification territoriale appropri\u00e9e.<\/p>\n<p>D\u2019un point de vue pratique, cela se traduit par la mise en \u0153uvre d\u2019un zonage fiable des dangers et des risques li\u00e9s aux glissements de terrain.<\/p>\n<p>Ce zonage devrait servir en particulier \u00e0 \u00e9viter tout accroissement des risques susceptible de mener \u00e0 des dommages humains et \u00e9conomiques inacceptables.<\/p>\n<p>Dans de nombreux pays, l\u2019expansion des zones urbaines se fait dans des zones sensibles aux glissements de terrain, avec ou sans \u00e9valuation pr\u00e9alable des risques \u00e0 l\u2019\u00e9chelle locale.<\/p>\n<p>Le zonage des secteurs \u00e0 risque n\u2019est cependant pas une mince affaire, car les terrains peuvent glisser sous l\u2019effet combin\u00e9 de pr\u00e9dispositions (morphologie et g\u00e9ologie du terrain, v\u00e9g\u00e9tation) et de diff\u00e9rents facteurs d\u00e9clenchants (causes physiques, g\u00e9omorphologiques, artificielles).<\/p>\n<p>Une \u00e9tape indispensable des \u00e9tudes de risques est souvent l\u2019\u00e9tablissement de cartes. Il peut s\u2019agir soit de documents simples (cartes g\u00e9omorphologiques et cartes des glissements de terrain), soit de cartes de susceptibilit\u00e9 aux mouvements de terrain et de zonage des risques.<\/p>\n<p>Go to 7.1. More information on the consequences of Landslides influenced by human behaviour<\/p>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-d9db5c8 elementor-widget elementor-widget-image\" data-id=\"d9db5c8\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"696\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/CommEpiscopiomudflow.jpg\" class=\"attachment-large size-large wp-image-2718\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Aerial view of the May 1998 mudflows in the town of Episcopio, Campania Region, Southern Italy (photo by http:\/\/www.commissario2994.it\/)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-6ca39d4 elementor-widget elementor-widget-accordion\" data-id=\"6ca39d4\" data-element_type=\"widget\" data-widget_type=\"accordion.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<div class=\"elementor-accordion\" role=\"tablist\">\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-1131\" class=\"elementor-tab-title\" data-tab=\"1\" role=\"tab\" aria-controls=\"elementor-tab-content-1131\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">7.1. More information on the consequences of Landslides influenced by human behaviour<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-1131\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"1\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-1131\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"2723\" class=\"elementor elementor-2723\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-8d604a3 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"8d604a3\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-f1f6e69\" data-id=\"f1f6e69\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-11be0e2 elementor-widget elementor-widget-text-editor\" data-id=\"11be0e2\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>The consequences of landslides can be influenced by human behaviour in relation to the possibility to answer to the questions \u201cwhere?\u201d, \u201cwhy?\u201d and \u201cwhen?\u201d a landslide phenomenon will occur and to realize an appropriate territorial planning.<\/p><p>From a practical point of vieuw it means to implement a reliable landslide hazard and risk zoning.<\/p><p>In particular, hazard zoning should be devoted to prevent further increase of risk, which could produce both an unacceptable number of casualties and economic hardship.<\/p><p>For example, in many countries the development of urban areas takes place in landslide prone areas with a fair or without control by a local planning.<\/p><p>Landslide hazard and risk zoning anyhow is not, however a simple topic because the landslides are associated with a displacement of masses due to several conditioning factors and under the effect of different triggering factors.<br \/><br \/>Go to 3.1. More informations on Factors and Causes<\/p><p>Go to 12.1 More information on Landslides Mapping<\/p><p>Several case histories teach that if the man is able to read the preliminary signs of a disaster many casualties can be avoid.<\/p><p><strong>References<\/strong><br \/>Cascini L,. Bonnard C., Corominas J., Jibson R. and Montero-Olarte J. 2005. Landslide hazard and Risk zoning for urban planning and development. Proc. of the Int. Conf. on Landslide Risk Management, Vancouver 31 may-3 june 2005, pp. 199-235, Ed. Balkema,<\/p><p>Go to 7. Can the consequences of landslides be influenced by human behaviour?<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p>\n<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-2088\" class=\"elementor-tab-title\" data-tab=\"8\" role=\"tab\" aria-controls=\"elementor-tab-content-2088\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">8. Les glissements de terrain sont-ils pr\u00e9visibles ?<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-2088\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"8\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-2088\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"7933\" class=\"elementor elementor-7933 elementor-2727\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-015da78 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"015da78\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-f647db0\" data-id=\"f647db0\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-0ba0e13 elementor-widget elementor-widget-text-editor\" data-id=\"0ba0e13\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>En comparaison d\u2019autres types de risques naturels, les glissements de terrain offrent un excellent potentiel de pr\u00e9vision spatiale et temporelle.<\/p>\n<p>Le lieu (\u00ab\u00a0o\u00f9\u00a0?\u00a0\u00bb) et les raisons (\u00ab\u00a0pourquoi\u00a0?\u00a0\u00bb) du d\u00e9clenchement d\u2019un mouvement de terrain d\u00e9pendent de son type\u00a0; il est plus ou moins ais\u00e9 de les d\u00e9terminer en analysant les donn\u00e9es g\u00e9ologiques, g\u00e9omorphologiques et g\u00e9otechniques du terrain.<\/p>\n<p>Le moment (\u00ab\u00a0quand\u00a0?\u00a0\u00bb) du d\u00e9clenchement peut quant \u00e0 lui \u00eatre pr\u00e9vu en analysant les donn\u00e9es climatiques et l\u2019historique des mouvements.<\/p>\n<p>Le d\u00e9clenchement (ou la r\u00e9activation) d\u2019un glissement de terrain peut faire suite \u00e0 diff\u00e9rents types d\u2019\u00e9pisodes m\u00e9t\u00e9orologiques. Cela \u00e9tant, certains mouvements de terrain n\u2019ont aucun lien apparent avec la m\u00e9t\u00e9orologie r\u00e9cente ou pass\u00e9e. Trois types de situations ont \u00e9t\u00e9 d\u00e9finis, en fonction du type de glissement de terrain\u00a0:<\/p>\n<ul>\n<li>pluies intenses (fortes pr\u00e9cipitations sur une courte dur\u00e9e),<\/li>\n<li>cumul de pr\u00e9cipitations sur une p\u00e9riode de dur\u00e9e variable avec apparition d\u2019un seuil de d\u00e9clenchement,<\/li>\n<li>cumul de pr\u00e9cipitations sur une p\u00e9riode de dur\u00e9e variable sans seuil de d\u00e9clenchement identifi\u00e9.<\/li>\n<\/ul>\n<p>On se rend compte, au vu de la grande diversit\u00e9 des ph\u00e9nom\u00e8nes, que les conditions de d\u00e9clenchement sont tr\u00e8s h\u00e9t\u00e9rog\u00e8nes.<\/p>\n<p>Une instabilit\u00e9 peut appara\u00eetre apr\u00e8s des mois de relative s\u00e9cheresse, pr\u00e9c\u00e9d\u00e9e ou non par de fortes pr\u00e9cipitations annuelles.<\/p>\n<p>A contrario, des pr\u00e9cipitations abondantes des ann\u00e9es, voire des d\u00e9cennies, auparavant peuvent suffire \u00e0 cr\u00e9er une instabilit\u00e9, m\u00eame si les pluies ont \u00e9t\u00e9 limit\u00e9es depuis. Le type de glissement de terrain joue bien \u00e9videmment un r\u00f4le fondamental dans cette relation.<\/p>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-8686680 elementor-widget elementor-widget-image\" data-id=\"8686680\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"784\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/VueLaValette_RiouChanal-1024x784.jpg\" class=\"attachment-large size-large wp-image-2732\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/VueLaValette_RiouChanal-1024x784.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/VueLaValette_RiouChanal-300x230.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/VueLaValette_RiouChanal-768x588.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/VueLaValette_RiouChanal.jpg 1273w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Location of the La Valette mudslide (photo by J.-P. Malet) In La Valette (Southern French Alps), about 200 buildings constructed below the slope were directly threatened when the mudslide triggered. Thus, a combination of protection and prevention techniques, monitoring systems and survey methods were necessary to reduce the risk and control the evolution of the landslide.<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-f29a07b elementor-widget elementor-widget-accordion\" data-id=\"f29a07b\" data-element_type=\"widget\" data-widget_type=\"accordion.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<div class=\"elementor-accordion\" role=\"tablist\">\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-2541\" class=\"elementor-tab-title\" data-tab=\"1\" role=\"tab\" aria-controls=\"elementor-tab-content-2541\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\"> 8.1. Landslides prevention, prediction and protection<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-2541\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"1\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-2541\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"2738\" class=\"elementor elementor-2738\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-a541949 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"a541949\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-5adba3a\" data-id=\"5adba3a\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-45e07f4 elementor-widget elementor-widget-text-editor\" data-id=\"45e07f4\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>The prevention of disasters due to landslides involves defining where a given type of movement will occur &#8211; the zone in which the probability of the occurrence is greatest. The answers to the questions \u201cwhere?\u201d and \u201cWhy?\u201d depend on the type of movement and are more or less easy to answer. Maps and documents written have been compiled by analysing geologic, geomorphologic and geotechnical data, using a historical inventory containing archives, photographs and the result of local investigations. The data may be analysed by statistical probability methods, using a GIS (Geographical Information System), for example, to demonstrate the respective weight of the various instability factors (Turner and Schuster, 1996).<\/p><p>The geological, geomorphological data on landslides involves research into indications of instability and the geotechnical information. The data may be analysed by statistical probability methods, using a GIS (Geographical Information System), for example, to demonstrate the respective weight of the various instability factors (Turner and Schuster, 1996).<\/p><p>(go to 8.1.1.More information on landslide investigation techniques)<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-2dcc914 elementor-widget elementor-widget-image\" data-id=\"2dcc914\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"715\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/RiskQuestiontessinaEnglish-1024x715.jpg\" class=\"attachment-large size-large wp-image-2741\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/RiskQuestiontessinaEnglish-1024x715.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/RiskQuestiontessinaEnglish-300x209.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/RiskQuestiontessinaEnglish-768x536.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/RiskQuestiontessinaEnglish-1536x1073.jpg 1536w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/RiskQuestiontessinaEnglish.jpg 1657w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-291155d elementor-widget elementor-widget-text-editor\" data-id=\"291155d\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>The answer to the question \u201cWhen?\u201d is obtained by analysing climatic conditions, in the vicinity or at a distance, which encourage instability and by establishing a relationship between the recorded earth movements (Maquaire, 1990; Matthews et al., 1997; Flageollet et al., 1999).<\/p><p>This amounts to defining the types of climate and their relationship to landslides. Flageollet et al. (1999) showed that the triggering or reactivation of landslides may be explained by several types of climate situation. However some landslides bear no obvious relation to climatic conditions, be they recent or more distant. They defined three main situations, depending on the type of landslide:<\/p><ul><li>heavy rainfall over a short period,<\/li><li>cumulative rainfall over a period of varying duration with establishment of a triggering threshold<\/li><li>cumulative rainfall over a period of varying duration without identification of a triggering threshold.<\/li><\/ul><p>The great diversity of the phenomena indicated that the conditions triggering them cannot be uniform. For deep slides, they involve the analysis of rainfall over previous weeks or months and the resulting piezometric variations must be taken into account, whereas for surface mudslides it is the intensity and quantity of rain falling over previous days and hours that is most relevant. In general, at a regional level there is a wide diversity in the relationships between the different types of landslide recorded and the climatic conditions, giving rise to a number of complex combinations. As frequently observed elsewhere, rainfall is only one element of the system that accelerates or triggers landslides and is combined with other factors, such as land-use. Generally, however, it is by far the most important element of the system.<\/p><p>Instability can even occur following relatively dry months, whether or not they are preceded by heavy annual rainfall. Conversely, heavy rainfall in earlier years or decades can be enough to trigger instability even if little rain has fallen over the preceding years. The type of landslide, of course, plays a fundamental role in this relationship. The complexity of relations between landslides and climatic conditions makes it difficult to define \u201cuniversal laws\u201d. Before that happens, further investigation is needed into such relations in a given area, taking account of the types of landslide, their generation (triggering or reactivation), the season of occurrence and, finally, the resulting initial degree of slope stability.<\/p><p>The risk from earth movements can be reduced and protection can be assured by preventive or curative works of two types. Active defence tackles the causes of the active or potential and mainly involves deep drainage or reforestation. Passive defence contains the materials which are or may be in movement, which generally involve terracing, reprofiling and retaining structures. For example, in some natural or artificial underground spaces in urban zones the space is frequently filled by injecting concrete, sand and bentonite.<\/p><p>In high-risk cases where there is considerable vulnerability and no way of reducing the hazard level the slopes must be monitored. Generally surface movements and variations in the water level are recorded continually and an alert is sounded automatically when a fixed threshold is exceeded.<\/p><p>In France, for example, two main sites in the Alps are fitted with instruments \u2013 the Clapi\u00e8re landslide at St. Etienne-de-Tin\u00e9e (Alpes-Maritimes) and the rockfall at the \u201cRuines de S\u00e9chilienne\u201d near Vizille (Is\u00e8re)<br \/>(<a href=\"http:\/\/www-lgit.obs.ujf-grenoble.fr\/observations\/omiv\/SECHILIENNE\/index.html\">http:\/\/www-lgit.obs.ujf-grenoble.fr\/observations\/omiv\/SECHILIENNE\/index.html<\/a>). Some sites are also fitted with instruments to serve as observatories for scientists involved in national or international research projects, in order to provide a better understanding of the various development processes and to develop and validate predictive models. The experimental site of the Super-Sauze earthflow (Go to 13.4. Super-Sauze,Study case) in the Alpes-de-Haute-Provence has been sounded, monitored and modelled since 1995 (Flageollet et al., 2000; Malet et al., 2000; Malet et al., 2001; Maquaire et al., 2001).<\/p><p>(Go to 13.7. Tessina Study case. To be sent by Pasuto)<br \/>Go to 8 Can LANDSLIDES be predicted?<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-adbc81b elementor-widget elementor-widget-accordion\" data-id=\"adbc81b\" data-element_type=\"widget\" data-widget_type=\"accordion.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<div class=\"elementor-accordion\" role=\"tablist\">\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-1821\" class=\"elementor-tab-title\" data-tab=\"1\" role=\"tab\" aria-controls=\"elementor-tab-content-1821\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">8.1.1. More information on landslide investigation techniques<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-1821\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"1\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-1821\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"2746\" class=\"elementor elementor-2746\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-2730dd9 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"2730dd9\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-0a548de\" data-id=\"0a548de\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-d259891 elementor-widget elementor-widget-text-editor\" data-id=\"d259891\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Investigation of existing landslides and sites of potential landslides plays an important role in landslide loss mitigation and in landslide research. Landslide investigations are used for different purposes:<\/p><ul><li>Identification and characterisation of unstable zones: triggering mechanisms? Causative factors (such as earthquakes or high rainfall events)? Estimated velocities?<\/li><li>Movements monitoring: long, medium and short term behaviour of the unstable slopes? Climatic conditions?<\/li><li>Movements modelling: how to explain the past movements? How to quantify these movements? How to predict future movements?<\/li><li>Hazard assessment: what will be the intensity and the frequency of crisis? Which scenario has to be taken into account?<\/li><li>Planning of stabilisation measures: how to decrease the movements? How to reduce the crises impacts?<\/li><\/ul><p>Different parameters are needed to be investigated:<\/p><ul><li>Ground properties: geometry, geology, hydrology, mechanical characteristics (stresses and forces), etc.<\/li><li>Surface and subsurface displacements<\/li><li>Groundwater levels and pressures<\/li><\/ul><p>Several techniques are used to determine these parameters. The figure 1 summarizes these techniques, which concern different domains such as geotechnics, geophysics, hydrology, remote-sensing:<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-b342946 elementor-widget elementor-widget-image\" data-id=\"b342946\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"709\" height=\"478\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/1_schema_van-asch.jpg\" class=\"attachment-large size-large wp-image-2749\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/1_schema_van-asch.jpg 709w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/1_schema_van-asch-300x202.jpg 300w\" sizes=\"(max-width: 709px) 100vw, 709px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 1: Multi-source strategy of investigation and monitoring of a slope movement (from Van Asch and al., 2007)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-0236f0f elementor-widget elementor-widget-text-editor\" data-id=\"0236f0f\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">The following parts describe the different methods indicated in the figure 1.<\/span><\/p><p><u><strong>A. Investigations of ground properties:<\/strong><\/u><\/p><p><strong>1. Ground geometry:<\/strong><\/p><p>Electrical tomography is a geophysical technique for imaging sub-surfaces structures from electrical measurements made at the surface. An electrical wave is propagated through the ground between two couples of electrodes anchored at the surface (A-B and M-N, figure 2). The resistivity of the terrain is measured. The more distant the couples of electrods are, the deeper the ground is investigated. Thus, resistivity is measured between different couples of electrodes along a line (figure 2).<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-8a66c64 elementor-widget elementor-widget-image\" data-id=\"8a66c64\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"768\" height=\"449\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_Electrictomography3-768x449.jpg\" class=\"attachment-medium_large size-medium_large wp-image-2754\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_Electrictomography3-768x449.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_Electrictomography3-300x175.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_Electrictomography3-1024x599.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_Electrictomography3-1536x898.jpg 1536w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_Electrictomography3-2048x1198.jpg 2048w\" sizes=\"(max-width: 768px) 100vw, 768px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 2: Principle of the electric tomography: measure of resistivity between two different couples of electrodes and at different depths<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-bd33f69 elementor-widget elementor-widget-text-editor\" data-id=\"bd33f69\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">Analysis of the resistivity values allows to determine the presence of different geological layers and their properties (nature, thickness). Indeed, different materials have not the same resistivity value (from Filliat, 1981):<\/span><\/p>\n<table class=\"table table-striped\">\n<thead>\n<tr>\n<th>Material<\/th>\n<th>Resistivity (ohm\/m)<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Clay<\/td>\n<td>3-30<\/td>\n<\/tr>\n<tr>\n<td>Marl<\/td>\n<td>10-100<\/td>\n<\/tr>\n<tr>\n<td>Schist<\/td>\n<td>30-300<\/td>\n<\/tr>\n<tr>\n<td>Sand and gravel<\/td>\n<td>100-1000<\/td>\n<\/tr>\n<tr>\n<td>Limestone<\/td>\n<td>300-3000<\/td>\n<\/tr>\n<tr>\n<td>Crystalline rocks<\/td>\n<td>1000-10000<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>Combination of the resistivity values allows to give information about ground structure in two dimensions (2D), establishing a resistivity profile (figure 3). It is possible to image ground to a depth of 100 metres.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-aee7d9b elementor-widget elementor-widget-image\" data-id=\"aee7d9b\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"768\" height=\"653\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/3_Resistivity1-768x653.jpg\" class=\"attachment-medium_large size-medium_large wp-image-2760\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/3_Resistivity1-768x653.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/3_Resistivity1-300x255.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/3_Resistivity1-1024x870.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/3_Resistivity1-1536x1305.jpg 1536w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/3_Resistivity1.jpg 1691w\" sizes=\"(max-width: 768px) 100vw, 768px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 3: Resistivity profile between two boreholes (from www.geotomographie.de\/lib\/elek2_en.gif)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-315e33c elementor-widget elementor-widget-image\" data-id=\"315e33c\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"428\" height=\"261\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/4_Electrode1.jpg\" class=\"attachment-large size-large wp-image-2765\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/4_Electrode1.jpg 428w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/4_Electrode1-300x183.jpg 300w\" sizes=\"(max-width: 428px) 100vw, 428px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 4: Electrode (photo by Arnaud, 2007)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-0e763c0 elementor-widget elementor-widget-image\" data-id=\"0e763c0\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"316\" height=\"277\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/5_resistivimetre1.jpg\" class=\"attachment-large size-large wp-image-2770\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/5_resistivimetre1.jpg 316w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/5_resistivimetre1-300x263.jpg 300w\" sizes=\"(max-width: 316px) 100vw, 316px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 5: Resistivimetre: fixed electrodes A and B which generate an electrical wave (photo by Arnaud, 2007)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-41868b4 elementor-widget elementor-widget-text-editor\" data-id=\"41868b4\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">Seismic tomography is also a geophysical technique for imaging sub-surfaces structures. It uses digital seismographic records to image the interior of the ground and thus determine geometry of the stratigraphic layers. An artificial seismic wave (acoustic wave) is generated by a shaking (explosion) at the ground surface. This seismic wave is propagated through the ground, directly or by refraction or reflection. Layers of different geological nature modify direction and velocity of the wave (figure 6).<\/span><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-ee6c779 elementor-widget elementor-widget-image\" data-id=\"ee6c779\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"557\" height=\"270\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/6_seismic_besson.jpg\" class=\"attachment-large size-large wp-image-2776\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/6_seismic_besson.jpg 557w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/6_seismic_besson-300x145.jpg 300w\" sizes=\"(max-width: 557px) 100vw, 557px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 6: Principle of the seismic tomography (from Besson, 2005)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-75f257e elementor-widget elementor-widget-text-editor\" data-id=\"75f257e\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">The time that the wave arrives at the seismic station is used to calculate the speed of the wave and to determine the presence of layers and some of their physical properties (density, thickness, etc.). Indeed, as the density of the material increases, the speed of the wave also increases (from Filliat, 1981):<\/span><\/p><p>Material Velocity (m\/s)<br \/>Mud and peat 50<br \/>Clay and silt 400-1500<br \/>Sand and gravel 300-1200<br \/>Altered rocks 800-2500<br \/>Massive rocks 2000-6000<\/p><p>Combination of values from several transmitting and receiving stations allows to give information about ground structure in 2D or 3D.<\/p><p>Georadar, or Ground-penetrating radar (GPR) is an other geophysical technique for imaging sub-surfaces structures. It uses electromagnetic radiation in the microwave band of the radio spectrum, and detects the reflected signals from subsurface structures. GPR uses transmitting and receiving antennas. The principles involved are similar to seismic tomography, except that electromagnetic energy is used instead of acoustic energy: the transmitting antenna radiates short pulses of the radio waves into the ground. When the wave hits a boundary with different dielectric constants, the receiving antenna records variations in the reflected return signal (figure 7).<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-ece7e72 elementor-widget elementor-widget-image\" data-id=\"ece7e72\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"241\" height=\"302\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/7_GPR.jpg\" class=\"attachment-large size-large wp-image-2782\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/7_GPR.jpg 241w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/7_GPR-239x300.jpg 239w\" sizes=\"(max-width: 241px) 100vw, 241px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 7: Principle of the GPR (from http:\/\/ilotresor.com\/prospection\/pro_gpr_accueil.html)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-cb84691 elementor-widget elementor-widget-text-editor\" data-id=\"cb84691\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">To carry out investigations on a large terrain, the distance between the two antennas remains constant and the couple of antennas is moved, or the middle between the two antennas remains constant and each antenna is moved.<\/span><\/p><p>The depth range of GPR is limited by the electrical conductivity of the ground (100 mS\/m), and the transmitting frequency. As conductivity increases, the penetration depth also decreases. Higher frequencies do not penetrate as far as lower frequencies, but give better resolution. Frequencies between 10 MHz and 1,5 GHz are generally used.<\/p><p>Depth penetration can reach 50 m. Optimal depth penetration is achieved in dry sandy soils or massive dry materials such as granite, limestone, and concrete. In moist and\/or clay laden soils and soils with high electrical conductivity, penetration is sometimes only a few centimetres.<\/p><p><strong>2. Mechanical characteristics:<\/strong><\/p><p>Vane shear testing is a geotechnical method. It is one of the most common in situ methods for the estimation of the undrained shear strength of soils. The equipment consists of a stainless steel vane, consisting of four rectangular blades, attached to the end of a steel rod. The vane is introduced into the ground to the depth where the measurement of the undrained shear strength is required. Then it is rotated and the torsional force required to cause shearing is calculated (figure 8). Figure 9 shows a manual vane shear test. The vane is rotated at a specified rate that should not exceed 0,1 degrees per second. The amount of rotation is specified in the green arrow whereas the red arrow has a device that measures the required Torque.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-8306f0b elementor-widget elementor-widget-image\" data-id=\"8306f0b\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"361\" height=\"424\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/8_vane_besson.jpg\" class=\"attachment-large size-large wp-image-2787\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/8_vane_besson.jpg 361w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/8_vane_besson-255x300.jpg 255w\" sizes=\"(max-width: 361px) 100vw, 361px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 8: Principle of the Vane shear test (from Besson, 2005)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-79ccf29 elementor-widget elementor-widget-image\" data-id=\"79ccf29\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"213\" height=\"244\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/9_vane-test.jpg\" class=\"attachment-large size-large wp-image-2792\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 9: Manual vane shear test for characterization of a site in the Bay Area, California (from www.geoengineer.org:vane.html)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-c3cafcc elementor-widget elementor-widget-image\" data-id=\"c3cafcc\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"185\" height=\"247\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/10_vane-tip.jpg\" class=\"attachment-large size-large wp-image-2797\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 10: Vane shear tip used in tests. The tip has a diameter of 7,5 cm and a height of 11,2 cm. Typically the ration of height to diameter should be 2 (from www.geoengineer.org:vane.html)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-8ef188b elementor-widget elementor-widget-text-editor\" data-id=\"8ef188b\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>This test is particularly well suited to measurements in soft clays.<\/p><p>Penetration test is also a geotechnical method. Penetration can be dynamic or static. It provides information on the penetration resistance and on the density of the material.<\/p><p>The dynamic penetration test uses a thick-walled sample tube which is driven into the ground by blows from a sliding hammer (figure 11). The sample tube is driven 150 mm into the ground and then the number of blows needed for the tube to penetrate each 150 mm is recorded. The sum of the number of blows required for the second and third 150 mm of penetration is the \u00ab\u00a0standard penetration resistance,\u00a0\u00bb or the \u00ab\u00a0N-value\u00a0\u00bb. The blow count provides an indication of the density of the ground, and it is used in many empirical geotechnical engineering formulae.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-b4c970a elementor-widget elementor-widget-image\" data-id=\"b4c970a\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"397\" height=\"512\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/11_penetrometr_besson.jpg\" class=\"attachment-large size-large wp-image-2802\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/11_penetrometr_besson.jpg 397w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/11_penetrometr_besson-233x300.jpg 233w\" sizes=\"(max-width: 397px) 100vw, 397px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 11: Principle of the dynamic penetration test (from Besson, 2005)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-175c5e5 elementor-widget elementor-widget-text-editor\" data-id=\"175c5e5\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">The main purpose of this test is to give information about the relative density of granular deposits such as gravels, sands or sandy clay from which it is often impossible to obtain undisturbed samples to study in laboratory. In conditions where the quality of the undisturbed sample is suspect, it is often advantageous to alternate the sampling with standard penetration tests to check the strength. The following table indicates standard values of penetration resistance for some materials (from Filliat, 1981):<\/span><\/p><p>Material Penetration resistance (MPa: 1 MPa = 10 bars)<br \/>Soft clay 0,02-0,2<br \/>Compact clay 0,2-0,8<br \/>Clayey sand 0,3-5<br \/>Sand 1,5-10<br \/>Sandy gravel 5-50<\/p><p>Finally, the dynamic penetration test is simple and inexpensive.<\/p><p>The cone penetration test is a static test which also measures the penetration resistance. It is rather used to investigate soft soils. It consists in pushing a cone tip into the ground at a constant and controlled rate (usually 2 centimeters\/second). The resolution of the cone penetration test in delineating stratigraphic layers is related to the size of the cone tip, with typical cone tips having diameters of around 4 cm.<\/p><p>The original cone penetrometers involved simple mechanical measurements of the total penetration resistance. Different methods were employed to separate the total measured resistance into components generated by the conical tip and friction generated by the rod string. Now, modern electronic cones also employ a pressure transducer with a filter to gather pore water pressure data. It aids determining stratigraphy and is primarily used to correct tip friction values. Moreover, the basic penetration probe has now additional instruments such as geophones or accelerometers to allow seismic investigations, or cameras for capturing video imagery.<\/p><p>Finally, compared to the dynamic penetration test, the cone penetration test is gaining popularity by its increased accuracy, speed of deployment and reduced cost.<\/p><p>Pressuremeter and dilatometer tests are also in situ geotechnical methods, which are loading tests run up to soil failure. They consist in pushing a cylindrical probe into a borehole. The diameter of the probe can be expanded by injecting pressurized air. These stresses are exerted on the walls of the borehole at different depths in order to determine layers the most sensitive to deformations (figure 12).<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-6eec7ea elementor-widget elementor-widget-image\" data-id=\"6eec7ea\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"442\" height=\"373\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/12_pressuremeter.jpg\" class=\"attachment-large size-large wp-image-2807\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/12_pressuremeter.jpg 442w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/12_pressuremeter-300x253.jpg 300w\" sizes=\"(max-width: 442px) 100vw, 442px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 12: Principle of the pressuremeter and the dilatometer tests (from www.roctest.com)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-e5ee403 elementor-widget elementor-widget-text-editor\" data-id=\"e5ee403\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">For a given depth, a pressuremeter test consists in regularly increasing the pressure and measuring the volume increment. The Menard test, which is called the normalized test must comprise about 10 steps of pressure of equal increment. The readings of the deformations are made at each step of pressure 15 seconds, 30 seconds and 1 minute after reaching the pressure level (figure 13).<\/span><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-875e8fa elementor-widget elementor-widget-image\" data-id=\"875e8fa\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"658\" height=\"305\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/13_menard-graph.jpg\" class=\"attachment-large size-large wp-image-2812\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/13_menard-graph.jpg 658w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/13_menard-graph-300x139.jpg 300w\" sizes=\"(max-width: 658px) 100vw, 658px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 13: Testing procedure of a Menard test (from www.roctest.com)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-4a78c37 elementor-widget elementor-widget-text-editor\" data-id=\"4a78c37\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">Then, a pressuremeter curve V = f(P) is obtained by drawing the deformations between 30 seconds and 1 minute versus the pressures. The curve presents 3 phases: the recompression phase, the pseudo-elastic phase, the plastic phase and rupture (figure 14, (from www.roctest.com)<\/span><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-a5b6361 elementor-widget elementor-widget-image\" data-id=\"a5b6361\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"597\" height=\"443\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/14_menard-graph-2.jpg\" class=\"attachment-large size-large wp-image-2817\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/14_menard-graph-2.jpg 597w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/14_menard-graph-2-300x223.jpg 300w\" sizes=\"(max-width: 597px) 100vw, 597px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-91a21ba elementor-widget elementor-widget-text-editor\" data-id=\"91a21ba\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Parameters obtained from pressuremeter and dilatometer tests are the limit pressure (pl), the creep pressure (pf) and the pressuremeter modulus (E). The pressuremeter modulus is based on a theoretical equation (Lame) giving the radial increment of a radial cavity in function of the pressure in an elastic medium. It varies according to the nature of the material (from Filliat, 1981):<\/p><p>Material Pressuremeter modulus E (MPa: 1 MPa = 10 bars)<br \/>Soft clay 0,5-3<br \/>Compact clay 3-30<br \/>Marl 1,5-10<br \/>Silty sand 3-10<br \/>Gravely sand 8-100<br \/>Calcareous rock 80-20000<\/p><p>The creep pressure corresponds to the end of the pseudo-elastic phase.<\/p><p>The limit pressure corresponds to the failure of the surrounding soil. It is given by the asymptote of the pressuremeter curve. As this asymptote is not always easy to define, the limit pressure is also defined as the pressure for which the volume of the initial cylindrical cavity has doubled.<br \/>Pressuremeter and dilatometer tests are rather used in soft terrains, but can be employed in all types of terrains, with high pressures. The instruments to carry out tests in the soils and soft rocks are called pressuremeters, the instruments to carry out tests in the rocks are called dilatometers.<\/p><p>The Menard pressuremeter test is the most common test. It consists of a tri-cellular probe giving a uniform and radial field of stresses in the central third. The radial deformation is deducted from the measurement of the injected volume. Parasitic dilatations are reduced with coaxial injection tubing. A very large number of Menard pressuremeter tests have been already performed in various materials, giving references of the long-term behaviour of structures and confidence in the use of empirical factors (figure 15 and 16).<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-6dca3c9 elementor-widget elementor-widget-image\" data-id=\"6dca3c9\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"682\" height=\"521\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/15_menard.jpg\" class=\"attachment-large size-large wp-image-2822\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/15_menard.jpg 682w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/15_menard-300x229.jpg 300w\" sizes=\"(max-width: 682px) 100vw, 682px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 15: Principle of the Menard pressuremeter(from www.roctest.com)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-7a43e39 elementor-widget elementor-widget-image\" data-id=\"7a43e39\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"193\" height=\"315\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/16_menard_capelle.jpg\" class=\"attachment-large size-large wp-image-2827\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/16_menard_capelle.jpg 193w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/16_menard_capelle-184x300.jpg 184w\" sizes=\"(max-width: 193px) 100vw, 193px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 16: Menard pressuremeter (from Capelle and al., 2005)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-172555c elementor-widget elementor-widget-text-editor\" data-id=\"172555c\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">Other pressuremeters and dilatometers exist. They can have a mono-cellular cell, can be hydraulically pressurized, etc.<\/span><\/p><p>Laboratory tests also exist to assess mechanical properties of soils, such as the direct shear test and the triaxial shear test\u2022to find the shear strength parameters of soil samples.<\/p><p><strong>3. Hydrological characteristics:<\/strong><\/p><p>Infiltrometer is a device used to measure in-situ the rate of water infiltration into soil. Both single ring and double ring infiltrometers exist, and at constant head or falling head. The Beerkan method is a simple three-dimensional infiltration test under constant head conditions, made in single cylinders. This test provides cumulative infiltration as a function of time. Measurements of particle size, initial and final water content, and dry bulk density are also required.<\/p><p>The cylinder is positioned at the soil surface and inserted to a depth of about 1 cm into the topsoil, to prevent lateral losses of water. The surface vegetation is removed, while the roots remain in-situ (figure 17). A fixed volume of water is poured into the cylinder at time zero, and the elapsed time during the infiltration of the known volume is measured. When the first volume has completely infiltrated, a second known volume of water is added to the cylinder, and the time needed for this to infiltrate is measured (cumulative time). The procedure is repeated for a series of about 8-15 known volumes of water. Then, cumulative infiltration time is used in infiltration equations to determine the saturated hydraulic conductivity.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-906e95b elementor-widget elementor-widget-image\" data-id=\"906e95b\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"285\" height=\"185\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/17_cylindre-beerkan-method.jpg\" class=\"attachment-large size-large wp-image-2833\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 17: Beerkan method (from www.lthe.hmg.inpg.fr\/P2H\/Equations_infiltration.htm)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-51fc922 elementor-widget elementor-widget-text-editor\" data-id=\"51fc922\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">Hydraulic conductivity (K) describes the ease with which water can move through pore spaces or fractures. It depends on the intrinsic permeability of the material and on the degree of saturation. Saturated hydraulic conductivity (Ksat) describes water movement through saturated media.<\/span><\/p><p>As Ksat increases, the permeability and thus the susceptibility to slope movement also incresases (from Musy et al., 1992):Ksat (m.s-1) 10-1 10-2 10-3 10-4 10-5 10-6 10-7 10-8 10-9 10-10 10-11<br \/>Permeability Permeable Semi-permeable Impermeable<br \/>Material Gravel Gravely sand<br \/>Coarse sand<br \/>Fine sand Fine sand<br \/>Coarse silt<br \/>Clayey silt Silty clay Homogeneous clay<br \/>Ksat is a parameter of the Darcy&rsquo;s law, which is a phenomologically equation that describes the flow of a fluid through a porous medium in saturated conditions (Q: flow, H:head):<\/p><p>Laboratory tests also exist to determine the saturated hydraulic conductivity. The constant-head permeameter is based on the Darcy\u2019s law. An undisturbed soil sample is collected in-situ in a known volume cylinder. Then in the laboratory the volume of water flowing through the soil sample is measured over a period of time. By knowing the volume V of water measured, length L of the sample, cross-sectional area S of the sample, time t required for the quantity of water V to be discharged, and head H, Ksat can be calculated:<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-879f938 elementor-widget elementor-widget-image\" data-id=\"879f938\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"410\" height=\"310\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/18_permeameter1.jpg\" class=\"attachment-large size-large wp-image-2839\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/18_permeameter1.jpg 410w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/18_permeameter1-300x227.jpg 300w\" sizes=\"(max-width: 410px) 100vw, 410px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 18: Constant-head permeameter equipment (photo by Trautmann, 2007)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-eabcc17 elementor-widget elementor-widget-text-editor\" data-id=\"eabcc17\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><u style=\"font-size: 1rem; text-align: left;\"><strong>B. Measurement of displacements:<\/strong><\/u><\/p><p>The main criteria to determine slope instability is the displacement. Indeed, kinematics monitoring provides a direct check on the stability of soil and rock slopes. Large movements are nearly always preceded by small displacements and accelerations that may be detected with instrumentation of sufficient sensitivity. Structural failure is commonly associated with a gradual acceleration of displacements. The time interval between the detection of the movement and the eventual collapse of a slope depends on the characteristics of the ground and on the sensitivity and reliability of the instruments. In most circumstances, a warning period from several days to weeks, or even months, may be achieved.<\/p><p><strong>1. Measurements of distances and coordinates<\/strong><\/p><p>Investigation of surface displacements can be achieved with several instruments measuring distances. A theodolite is a conventional topometric survey technique to measure distances. It is often used to monitor settlement at the crest of a slope or along the intermediates benches on a slope face. It measures both horizontal and vertical angles. A modern theodolite consists of a telescope mounted movably within two horizontal and vertical axis. It is mounted on a tripod (figure 19).<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-b6b7683 elementor-widget elementor-widget-image\" data-id=\"b6b7683\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"253\" height=\"313\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/19ppp.jpg\" class=\"attachment-large size-large wp-image-2845\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/19ppp.jpg 253w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/19ppp-242x300.jpg 242w\" sizes=\"(max-width: 253px) 100vw, 253px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 19: Theodolite mounted on a tripod (photo by Arnaud, 2007)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-5716aa0 elementor-widget elementor-widget-text-editor\" data-id=\"5716aa0\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">Before use, a theodolite must be placed precisely and vertically over the target to be measured and its vertical axis must be aligned with local gravity. It can be done using a plumb bob and a spirit level. The theodolite can also be mounted on a tribrach, which consists of two triangular metal plates, which are connected at their corners by thumbscrews. The bottom plate is mounted on the tripod and by turning the thumbscrews, it is possible to level the theodolite. The theodolite can be motorized or not.<\/span><\/p><p>Both axis in the theodolite are equipped with graduated circles. The axis must be mutually perpendicular. The condition where they deviate from perpendicularity is referred to as horizontal axis error. The optical axis of the telescope, called sight axis must be perpendicular to the horizontal axis. If not, the deviation is called collimation error. These errors are regularly determined by calibration, and removed by mechanical adjustment (figure 20).<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-a0d956b elementor-widget elementor-widget-image\" data-id=\"a0d956b\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"641\" height=\"541\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/20_theodolite_wikipedia.jpg\" class=\"attachment-large size-large wp-image-2850\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/20_theodolite_wikipedia.jpg 641w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/20_theodolite_wikipedia-300x253.jpg 300w\" sizes=\"(max-width: 641px) 100vw, 641px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 20: Principle of the theodolite (from en.wikipedia.org)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-1d09385 elementor-widget elementor-widget-text-editor\" data-id=\"1d09385\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">The modern theodolites employ a laser beam to measure the distances. The distance is measured with the time taken for the beam to travel from the instrument to the target. This distance between a fixed and stable instrument base and a target on the slope face can be used directly as a measure of slope movement. The accuracy of electro-optic measurement is generally from 1 to 10 mm. It is limited by atmospheric temperatures and pressure variations. Lines of sight located in zones of atmospheric turbulence should be avoided.<\/span><\/p><p>Alternatively the target coordinates may be determined by triangulation and trilateration calculations (figure 21).<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-552193a elementor-widget elementor-widget-image\" data-id=\"552193a\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"490\" height=\"294\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/21_triangulation.jpg\" class=\"attachment-large size-large wp-image-2855\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/21_triangulation.jpg 490w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/21_triangulation-300x180.jpg 300w\" sizes=\"(max-width: 490px) 100vw, 490px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 21: Principle of triangulation (from bonnard, 2007)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-d7207f9 elementor-widget elementor-widget-text-editor\" data-id=\"d7207f9\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">The Global Positioning System (GPS) is a widely used instrument to measure active deformations of the Earth\u2019s crust, providing 3-D coordinates of a target. The monitoring of landslides with GPS is usually performed using repeated campaigns, as a complement to conventional topometric methods (teodolithe).<\/span><\/p><p>GPS is based on a constellation of 26 Medium Earth Orbit satellites, which transmit microwave signals. Each satellite has an atomic clock, and continually transmits messages, each containing the current time at the start of the message, parameters to calculate the location of the satellite and the general system health. The signals travel at the speed of light through outer space, and slightly slower through the atmosphere.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-874fe4b elementor-widget elementor-widget-image\" data-id=\"874fe4b\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"247\" height=\"218\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/22_orbites.jpg\" class=\"attachment-large size-large wp-image-2860\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 22: 26 Medium Earth Orbit satellites (from Bonnard, 2007)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-bcf1a7a elementor-widget elementor-widget-text-editor\" data-id=\"bcf1a7a\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">The GPS receiver uses the arrival time to compute the distance to each satellite, from which it determines its position using geometry and trigonometry (trilateration method). A typical GPS receiver calculates its position using the signals from four satellites.<\/span><\/p><p>Two utilization modes exist (figure 23): absolute mode provides a \u201creal-time\u201d absolute position with accuracy between 10 and 100 m. Only one receiver is needed. Advantages are that this method is simple and many measurements can be made in a short time. To obtain a better accuracy, differential mode is used. Two receivers are used and the obtained position is relative. Accuracy is function of the type of receiver and the duration of observation sessions. The differential system can be static or cinematic. In the cinematic differential mode, one receiver is fixed and one is mobile (figure 24). It provides positions with millimetre-level accuracy.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-c3670ce elementor-widget elementor-widget-image\" data-id=\"c3670ce\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"720\" height=\"448\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/23_gps.jpg\" class=\"attachment-large size-large wp-image-2866\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/23_gps.jpg 720w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/23_gps-300x187.jpg 300w\" sizes=\"(max-width: 720px) 100vw, 720px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 23: GPS modes (from Hermann, 2004)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-78be598 elementor-widget elementor-widget-image\" data-id=\"78be598\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"488\" height=\"364\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/24_GPSutilization1.jpg\" class=\"attachment-large size-large wp-image-2871\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/24_GPSutilization1.jpg 488w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/24_GPSutilization1-300x224.jpg 300w\" sizes=\"(max-width: 488px) 100vw, 488px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 24: Cinematic differential GPS utilization. The photo shows the fix receiver (red arrow) and the moving receiver (white arrow) (from Maquaire, 2005)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-be8b477 elementor-widget elementor-widget-text-editor\" data-id=\"be8b477\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">Although high accuracy obtained with GPS, continuous monitoring of landslides with GPS is not usually performed because of the cost of such a system compared to conventional deformation monitoring techniques. In addition, millimetre-level accuracy can be obtained for long observation sessions (typically 24 h), it decreases with the duration of the sessions, because of errors introduced by variations of the satellite constellation and multipath effects when the radio signals reflect off surrounding terrain. However, in case of inaccessible terrains, GPS appears to be the only one method to provide reliable position measurements.<\/span><\/p><p><strong>2. Use of remote-sensing techniques:<\/strong><\/p><p>Remote-sensing is the collecting of information about an object or phenomenon by the use of sensing devices not in physical or intimate contact with the subject under investigation. Both space and aerial remote-sensing techniques exist, thus including space-borne and air-borne platforms. Interpretation of satellital and aerial photographies is widely used for many purposes in slope instability investigations. Notably, a sequence of photographs taken at suitable time intervals can be compared to examine the progressive development of slides.<\/p><p>There are two kinds of remote-sensing techniques. On the one hand, passive sensors detect natural energy (radiation) that is emitted or reflected by the object or surrounding area being observed. Reflected sunlight is the most common source of radiation measured by passive sensors. On the other hand, active sensors emit energy in order to scan objects and areas and then detect and measure the radiation that is reflected by the object. RADAR (Radio Detection and Ranging) is an example of active satellital remote-sensing. The most advanced RADAR technology is SAR interferometry (synthetic aperture radar).<\/p><p>It is a powerful tool, providing an image representing the motion with a centimetric precision and with a decametric resolution. Data acquired by SAR systems can provide digital elevation models in three dimensions. Moreover, this technique has already proven its capability to detect and to map movement fields in landslide areas. One of the currently operating space-borne radar systems is the European ERS-2 satellite, whose side-looking SAR sensor images the Earth from an orbit about 780 km above the Earth surface.<\/p><p>LIDAR (Light Detection and Ranging) is an other advanced remote-sensing technology similar to RADAR technology: the range to an object is determined by measuring the time delay between transmission of a pulse and detection of the reflected signal. The difference with RADAR system is that LIDAR system uses shorter wavelengths of the electromagnetic spectrum, typically in the ultraviolet, visible, or near infrared. RADAR system uses radio waves or microwaves. Then, LIDAR is a air-borne technology, instead of a space-borne technology. It is used to measure heights of objects and features on the ground more accurately than with RADAR technology.<\/p><p>Terrestrial photogrammetry also exists. Photographs are taken from grounds stations and are measured in a stereo comparator.<\/p><p><strong>3. Measurements of surface displacements and cracks, joints and faults<\/strong><\/p><p>Monitoring of tension cracking that develops at the crest of the potentially unstable slope can provide useful information concerning the mechanisms and directions of movement. First, it can be helpful to mark the entire length of each crack with spray paint and to delineate the pattern of cracking on plans and cross-sections of the structure. At each subsequent date of observation it is then possible to note the appearance of new cracks, and the elongation of cracks previously marked.<\/p><p>Then, several portable instruments are available to measure the expansion in aperture of the cracks. An example is the Demec gauge (demountable mechanical strain gauge) designed originally for measuring crack movements in concrete beams. Steel discs with a central indentation for locating the gauge are cemented on the rock surface on each side of the crack. The portable gauge employs a dial indicator actuated by a level system and is used to measure the distance between the discs.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-553b127 elementor-widget elementor-widget-image\" data-id=\"553b127\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"383\" height=\"254\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/25_demec-schema.jpg\" class=\"attachment-large size-large wp-image-2877\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/25_demec-schema.jpg 383w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/25_demec-schema-300x199.jpg 300w\" sizes=\"(max-width: 383px) 100vw, 383px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 25: Principle of the Demec gauge (from Clayton and al., 2005)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-374f3e2 elementor-widget elementor-widget-image\" data-id=\"374f3e2\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"249\" height=\"125\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/26_demec-photo.jpg\" class=\"attachment-large size-large wp-image-2882\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 26: Demec gauge (from www.mayes.co.uk\/6.html)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-bb8e3f5 elementor-widget elementor-widget-text-editor\" data-id=\"bb8e3f5\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">Extensometers are also employed to measure extension movements at the ground surface. Two steel or aluminium anchor bolts are secured in the ground by grouting on each side of the crack or the crown. The most common extensometer consists of an Invar cable (FeSi) tight between the two anchor bolts. One bolt is anchored in the instable area and one bolt is anchored in the stable area. One end of the cable is mounted with a pulley and one end has a freely suspended weight. Displacement of the instable material makes the cable wind round the pulley. A potentiometer connected to the axis of the pulley creates an electric signal. This signal is then converted into extension distance (figure 27).<\/span><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-2ce8e0c elementor-widget elementor-widget-image\" data-id=\"2ce8e0c\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"330\" height=\"253\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/27_extensomtre-super-sauze.jpg\" class=\"attachment-large size-large wp-image-2888\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/27_extensomtre-super-sauze.jpg 330w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/27_extensomtre-super-sauze-300x230.jpg 300w\" sizes=\"(max-width: 330px) 100vw, 330px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 27: Principle of the extensometer with Invar cable for the monitoring of the Super-Sauze landslide, France (from Malet, 2003) (see CaseStudy Super-Sauze)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-1a9614e elementor-widget elementor-widget-image\" data-id=\"1a9614e\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"323\" height=\"480\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/28_clapire_besson.jpg\" class=\"attachment-large size-large wp-image-2894\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/28_clapire_besson.jpg 323w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/28_clapire_besson-202x300.jpg 202w\" sizes=\"(max-width: 323px) 100vw, 323px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 28: Extensometer, La Clapi\u00e8re landslide, France. Because the displacements are important (superior to one centimetre per day), accuracy of the installation is not necessary: a trunk is used to support the system. The invar wire and the suspended weight are well visible (from LCPC, 1994)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-bf3ecde elementor-widget elementor-widget-image\" data-id=\"bf3ecde\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"333\" height=\"485\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/29_extensometer_ancey.jpg\" class=\"attachment-large size-large wp-image-2899\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/29_extensometer_ancey.jpg 333w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/29_extensometer_ancey-206x300.jpg 206w\" sizes=\"(max-width: 333px) 100vw, 333px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 29: Extensometer with continuous recording at Saas Fee Landslide. The pulley (red delineation) is also mounted on a tree trunk (from Bonnard, 2007)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-bcec91d elementor-widget elementor-widget-image\" data-id=\"bcec91d\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"687\" height=\"474\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/30_extensomtre-sechilienne.jpg\" class=\"attachment-large size-large wp-image-2904\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/30_extensomtre-sechilienne.jpg 687w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/30_extensomtre-sechilienne-300x207.jpg 300w\" sizes=\"(max-width: 687px) 100vw, 687px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 30: one of the 49 extensometers installed on the Sechilienne rockfall, Is\u00e8re, France.<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-8a94ed6 elementor-widget elementor-widget-text-editor\" data-id=\"8a94ed6\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">They continuously measure aperture of the most active cracks with an accuracy of 0,1 mm. The suspended weight is well visible (from www.irma-grenoble.com)<\/span><\/p><p><strong>4. Measurements of sub-surface displacements<\/strong><\/p><p>The inclinometer measures the change in inclination of a casing in a borehole and thus allows the distribution of lateral movements to be determined as a function of depth and time. In a landslide, this method is used to define the slip surface or zones of movement relative to stable zones. Inclinometer is also used to monitor dams, bulkheads and other earth-retaining structures.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-6a1408c elementor-widget elementor-widget-image\" data-id=\"6a1408c\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"494\" height=\"207\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/31_inclinometer_trb.jpg\" class=\"attachment-large size-large wp-image-2909\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/31_inclinometer_trb.jpg 494w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/31_inclinometer_trb-300x126.jpg 300w\" sizes=\"(max-width: 494px) 100vw, 494px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 31: Inclinometer: sensor unit, control cable and control and readout unit (from TRB, 1978).<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-15e6f3b elementor-widget elementor-widget-text-editor\" data-id=\"15e6f3b\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">An inclinometer system has four components (figures 31 and 32):<\/span><\/p><ul><li>A guide casing is permanently installed in a vertical borehole into the ground. This casing may be made of plastic, steel or aluminium. It is fixed into the rock, so it is in movement with the slope,<\/li><li>A portable sensor unit is commonly mounted in a carriage designed for operation in the guide casing,<\/li><li>A control cable raises and lowers the sensor unit in the casing and transmits electrical signals to the surface,<\/li><li>A portable control and readout unit at the surface supplies power, receives electrical signals and displays readings in dial or digital format.<\/li><\/ul><p>The responses to slope changes in the casing are monitored and recorded at the surface. Readings are taken at fixed, usually equal increments throughout the entire depth. Instruments differ primarily in the type of sensor used, in the accuracy with which the sensor detects the inclination, and in the method of alignment and depth control within the borehole.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-f417cde elementor-widget elementor-widget-image\" data-id=\"f417cde\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"455\" height=\"485\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/32_inclinometer2_trb.jpg\" class=\"attachment-large size-large wp-image-2914\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/32_inclinometer2_trb.jpg 455w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/32_inclinometer2_trb-281x300.jpg 281w\" sizes=\"(max-width: 455px) 100vw, 455px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 32: Principle of the inclinometer (from TRB, 1978)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-e190350 elementor-widget elementor-widget-image\" data-id=\"e190350\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"513\" height=\"884\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/33_inclinometer_besson.jpg\" class=\"attachment-large size-large wp-image-2919\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/33_inclinometer_besson.jpg 513w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/33_inclinometer_besson-174x300.jpg 174w\" sizes=\"(max-width: 513px) 100vw, 513px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 33: Principle of the inclinometer operation (from Besson, 2005)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-6006068 elementor-widget elementor-widget-image\" data-id=\"6006068\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"350\" height=\"533\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/34_inclinometer_photo_bonnard.jpg\" class=\"attachment-large size-large wp-image-2924\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/34_inclinometer_photo_bonnard.jpg 350w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/34_inclinometer_photo_bonnard-197x300.jpg 197w\" sizes=\"(max-width: 350px) 100vw, 350px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 34: Inclinometer investigation (from Bonnard, 2007)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-5e71ad9 elementor-widget elementor-widget-text-editor\" data-id=\"5e71ad9\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><u style=\"font-size: 1rem; text-align: left;\"><strong>C. Measurements of groundwater levels and pressures<\/strong><\/u><\/p><p>Groundwater has an important influence on the stability of soil and rock slopes (&gt;&gt;More details on the role of water). Piezometric monitoring is necessary to determine excessive water discharge or excessive water pressure.<\/p><p>Water pressure is monitored using a piezometer, a geotechnical method which consists of a standpipe inserted in a drillhole. The standpipe is a tube perforated at its lower end or fitted with a porous plastic ceramic element. Its end is packed with filter material (coarse sand or gravel). The remainder of the borehole is backfilled with cement grout to hydraulically isolate the piezometer. Groundwater rises in the standpipe until water head is in equilibrium with water pressure in the ground around the piezometer tip.<\/p><p>Groundwater pressure in the tip is monitored using a water level probe. It is a twin conductor cable with the end of each conductor connected to a brass cylinder. Entry of the probe into the water completes an electric circuit and activates a buzzer or lamp indicator on the cable reel. The cable is graduated along its length so that the distance between the water level and the collar of the standpipe tube can be measured (figure 35).<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-59c00b1 elementor-widget elementor-widget-image\" data-id=\"59c00b1\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"456\" height=\"610\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/35_piezometre_besson.jpg\" class=\"attachment-large size-large wp-image-2929\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/35_piezometre_besson.jpg 456w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/35_piezometre_besson-224x300.jpg 224w\" sizes=\"(max-width: 456px) 100vw, 456px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 35: Principle of the piezometer (from Besson, 2005)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-0a4b54b elementor-widget elementor-widget-image\" data-id=\"0a4b54b\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"203\" height=\"290\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/36_piezo.jpg\" class=\"attachment-large size-large wp-image-2934\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 36: Piezometer and piezometric probe (from agire.brgm.fr\/Garonne.htm)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-4448e22 elementor-widget elementor-widget-text-editor\" data-id=\"4448e22\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">Some piezometers are adapted to measure large pressures or large pressure fluctuations. For example, water in the standpipe can take a considerable time to be in equilibrium with water in the ground around the piezometer, from a few minutes to several days. It depends of the permeability of the ground. This can be a problem when relatively rapid fluctuations in groundwater pressure are expected and when the ground is impermeable.<\/span><\/p><p>Hydraulic twin tube piezometer overcomes this problem, having a much smaller diameter of tube. This type of piezometer consists of a porous plastic or ceramic element connected by two flexible plastic tubes to a mercury manometer. The groundwater pressure is balanced by a head of mercury in the manometer, which is read against a calibrated scale. Generally, a hydraulic piezometer is only employed when the minimum head to be recorded is less than 8 meters below ground level.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-02ea064 elementor-widget elementor-widget-image\" data-id=\"02ea064\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"461\" height=\"283\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/37_hydraulic-piezo.jpg\" class=\"attachment-large size-large wp-image-2939\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/37_hydraulic-piezo.jpg 461w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/37_hydraulic-piezo-300x184.jpg 300w\" sizes=\"(max-width: 461px) 100vw, 461px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 37: Twin tube hydraulic piezometer equipment (from Clayton and al., 2005)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-accc04f elementor-widget elementor-widget-text-editor\" data-id=\"accc04f\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">Pneumatic piezometer consists of a porous plastic or ceramic element connected to an air activated pressure cell, which is connected by flexible plastic tubes to a gauge system at the ground surface. Changes in groundwater pressure are measured by injecting air under pressure down one of the twin tubes, sufficient to balance the water pressure on the reverse side of the transducer diaphragm. The pressure sufficient to cause a return flow of air along the second plastic tube is recorded and is equal to the groundwater pressure. Only a very small diaphragm reflection is necessary to permit return flow, so that the volume change is minimal. This type of piezometer has a rapid response to groundwater pressure fluctuations.<\/span><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-4194748 elementor-widget elementor-widget-image\" data-id=\"4194748\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"399\" height=\"386\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/38_pneumatic-piezo.jpg\" class=\"attachment-large size-large wp-image-2944\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/38_pneumatic-piezo.jpg 399w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/38_pneumatic-piezo-300x290.jpg 300w\" sizes=\"(max-width: 399px) 100vw, 399px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 38: Pneumatic piezometer equipment (from Clayton and al., 2005)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-c4b8bf6 elementor-widget elementor-widget-text-editor\" data-id=\"c4b8bf6\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">Finally, electric piezometer consists of a porous plastic or ceramic element connected to an electric transducer. Electric leads from the transducer connect the piezometer tip to the readout instrument at the ground surface. This type of piezometer has a rapid response to groundwater pressure fluctuations and may be used as an alternative to the pneumatic types in materials of low permeability, such as clays. Moreover, electric piezometer allows automatic recording of pressure fluctuations.<\/span><\/p><p>When installing electric or pneumatic instruments, care should be taken to ensure that the piezometer tip is thoroughly saturated with de-aired water, since even small amounts of air in the equipment lead to inaccurate readings.<\/p><p>For examples of application of the different investigation techniques described in this part, go to\u00a013.3. La Valette Case Study and 13.4 Super-Sauze CaseStudy.<\/p><p><strong>References:<\/strong><\/p><p>BESSON L., 2005. Les risques naturels: de la connaissance pratique \u00e0 la gestion administrative. Editions Techni. Cit\u00e9s, Voiron, 60 p.<br \/>BONNARD C., 2007. Introduction on landslide investigation. Mountain Risks Workshop, Switzerland, 96 p.<br \/>BRAUD I., DE CONDAPPA D., SORIA J.M., HAVERKAMP R., ANGULO-JARAMILLO R., GALLE S., VAUCLIN M., 2005. Use of scaled forms of the infiltration equation for the estimation of unsaturated soil hydraulic properties (the Beerkan method). European Journal of Soil Sciences, n\u00b056, p. 361-374<br \/>BRUNSDEN D., PRIOR D., 1984. Slope instability. John Wiley &amp; Sons Ltd, Chichester<br \/>CAPELLE J.F., MARCIL L., QUIRION M., HUGHES J.M. 2005. Contributions of Canadian experiments to the development of pressuremeter techniques. Symposium International ISP5-PRESSIO, 10 p. www.roctest.com<br \/>CLAYTON C. R. I., MATTHEWS M. C., SIMONS N. E., 2005. Site investigation-Chapter 10:Basic field instrumentation for site investigation. University of Surrey. www.geotechnique.info<br \/>COLESANTI C., WASOWSKI J., 2006. Investigating landslides with space-borne Synthetic Aperture Radar (SAR) interferometry. Engineering Geology, n\u00b0 88, p. 173\u2013199<br \/>LABORATOIRE CENTRAL DES PONTS ET CHAUSSEES (LCPC), 1994. Surveillance des pentes instables -guide technique. Minist\u00e8re de l\u2019Equipement, des Transports et du Tourisme (METT), Techniques et M\u00e9thodes des Laboratoires des Ponts et Chauss\u00e9es, Paris<br \/>MALET J.P. Les \u00ab glissement de type \u00e9coulement \u00bb dans les marnes noires des Alpes du sud. Morphologie, fonctionnement et mod\u00e9lisation hydrom\u00e9canique. PhD Thesis: Institut de Physique du Globe, Universit\u00e9 Louis Pasteur de Strasbourg, 2003. 353 p.<br \/>MALET J.P., MAQUAIRE O., CALAIS E., 2002. Le GPS en g\u00e9omorphologie dynamique. Application \u00e0 la surveillance de mouvements de terrain (Super-Sauze, Alpes du Sud, France). G\u00e9omorphologie : relief, processus, environnement, n\u00b0 2, p. 165-180<br \/>RocTest. Pressuremeter and dilatometer tests &#8211; Interpretation and results. 34 p. www.roctest.com<br \/>SCHULZ H., 2006. Landslide susceptibility revealed by LIDAR imagery and historical records, Seattle, Washington. Engineering geology, n\u00b0 89, p. 67-87<br \/>SLOSSON E., KEENE A.G., JOHNSON J.A., 1992. Landslides\/Landslide mitigation. In: Reviews of Engineering Geology, Volume IX, Colorado<br \/>TRANSPORTATION RESEARCH BOARD, 1978. Landslides: Analysis and Control. National Academy of Sciences, Special Report 176, Washington DC<br \/>VAN ASCH T., MALET J.P., VAN BEEK L., AMITRANO D., 2007. Techniques, issues and advances in numerical modelling of landslide hazard. Bulletin de la soci\u00e9t\u00e9 g\u00e9ologique de France, n\u00b0178, p. 265-288<\/p><p>Website:\u00a0<a href=\"http:\/\/en.wikipedia.org\/\" target=\"_blank\" rel=\"noopener\">en.wikipedia.org<\/a><\/p><p>Go to 8 Can LANDSLIDES be predicted?<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p>\n<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-2089\" class=\"elementor-tab-title\" data-tab=\"9\" role=\"tab\" aria-controls=\"elementor-tab-content-2089\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">9. Est-il possible d\u2019emp\u00eacher un glissement de terrain de survenir ?<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-2089\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"9\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-2089\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"7935\" class=\"elementor elementor-7935 elementor-2950\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-5609e72 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"5609e72\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-640b99b\" data-id=\"640b99b\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-81acf59 elementor-widget elementor-widget-text-editor\" data-id=\"81acf59\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>La pr\u00e9vention d\u2019un glissement de terrain n\u00e9cessite en g\u00e9n\u00e9ral de mener \u00e0 bien plusieurs \u00e9tapes.<\/p>\n<p>1. \u00c9tudes pr\u00e9liminaires pour proc\u00e9der \u00e0 la cartographie des zones sensibles aux mouvements de terrains.<br \/>\n2. \u00c9valuation du risque de glissement de terrain \u00e0 la lumi\u00e8re de ces \u00e9tudes.<br \/>\n3. Identification des \u00e9l\u00e9ments expos\u00e9s et \u00e9valuation de leur vuln\u00e9rabilit\u00e9 afin d\u2019inclure l\u2019al\u00e9a glissement de terrain dans la planification territoriale.<\/p>\n<p>Il en r\u00e9sulte une carte des zones sensibles qui d\u00e9finit les terrains constructibles ou inconstructibles, en fonction du niveau de risque et de vuln\u00e9rabilit\u00e9.<\/p>\n<p>La pr\u00e9vention des effondrements, comme celle des glissements de terrain en g\u00e9n\u00e9ral, se d\u00e9roule en plusieurs \u00e9tapes successives, dont certaines n\u00e9cessitent des techniques adapt\u00e9es de d\u00e9tection des cavit\u00e9s.<\/p>\n<p>Les op\u00e9rations les plus couramment men\u00e9es sont les suivantes\u00a0:<br \/>\n1. Reconnaissance pr\u00e9alable pour identifier les zones menac\u00e9es d\u2019effondrement.<br \/>\n2. D\u00e9tection des cavit\u00e9s \u00e0 partir d\u2019une s\u00e9lection de zones \u00e0 risque sp\u00e9cifiques (r\u00e9alis\u00e9e lors de la premi\u00e8re \u00e9tape), pour localiser pr\u00e9cis\u00e9ment les cavit\u00e9s et zones de d\u00e9pression (surfaces et volumes)<\/p>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-a48168f elementor-widget elementor-widget-image\" data-id=\"a48168f\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"697\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/9-vaerdal-1024x697.jpg\" class=\"attachment-large size-large wp-image-2955\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/9-vaerdal-1024x697.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/9-vaerdal-300x204.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/9-vaerdal-768x523.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/9-vaerdal-1536x1046.jpg 1536w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/9-vaerdal.jpg 1735w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Print of soil spreading failure at Vaerdal, Norway (from Bierrum, L. 1955)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-b77868d elementor-widget elementor-widget-accordion\" data-id=\"b77868d\" data-element_type=\"widget\" data-widget_type=\"accordion.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<div class=\"elementor-accordion\" role=\"tablist\">\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-1921\" class=\"elementor-tab-title\" data-tab=\"1\" role=\"tab\" aria-controls=\"elementor-tab-content-1921\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">9.1. Falls, rockafall avalanches and Topples prevention and protection<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-1921\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"1\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-1921\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"2961\" class=\"elementor elementor-2961\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-3c0deeb elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"3c0deeb\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-ee22036\" data-id=\"ee22036\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-907bb5d elementor-widget elementor-widget-text-editor\" data-id=\"907bb5d\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><u><strong>Techniques of prevention<\/strong><\/u><\/p><p>The main implication for a planner is to ensure that there are suitable surveys of areas which are likely to produce falls. These surveys are carried out by engineering geologists and geomorphologists. The purpose of these is the identification of the sectors prone to fall. It is possible with research of surface indices such as distribution of fissures and pattern of rock discontinuities.<\/p><p>As concern rock avalanches, with advanced investigations and development of predictive models it is possible to identify some of the likely areas for failure and to gain some idea of the possible run-out distance for a given volume. The identification of the sectors prone to topple is possible with research of surface indices such as open cracks.<\/p><p>These investigations lead to fall hazard assessment. Then, elements at risk are identified and their vulnerability is assessed in order to include fall hazard in town planning. The result is a zoning map which defines terrains which can be built or not, according to the degree of hazard and vulnerability (see more information on landslide mapping). Monitoring systems should also be installed in high risk areas.<\/p><p><u><strong>Techniques of protection<\/strong><\/u><\/p><p>These techniques can be only used for reducing controllable and small-scale fall hazards. In high-risk and large-scale cases there is generally no technical solution. These sites require to be continuously monitored. In France, the \u201cRuines de S\u00e9chilienne\u201d rockfall, near Vizille (Is\u00e8re) is a good example of monitoring strategy in combination with urban planning.<\/p><p>Techniques of protection can be classified in two distinct categories:<br \/>&#8211; \u201cActive techniques\u201d: they avoid the triggering of the fall. They mainly consist in reinforcement systems which retain the material (rock or soil) on the steep slope or the cliff.<br \/>&#8211; \u201cPassive techniques\u201d: they seek to control the consequences of the fall. They aim at interposing a \u201cscreen\u201d between the steep slope and vulnerable elements.<\/p><p>A. Active techniques:<\/p><p>&#8211; Steel reinforcement<\/p><p>Reinforcement systems add strength to the rock mass by increasing the general tensile strength and by improving its resistance to shear along discontinuities. Both active and passive steel reinforcement systems are used for stabilizing rock slopes. The active system involves tensioned or prestressed bars or cables that have been anchored at one end within the rock mass by mechanical means or by cement or chemical grouts or by both. The passive system involves untensioned bars that have been fully grouted throughout their length by cement or chemical grouts. The main advantage of the active system over the passive system is that no movement has to take place before the anchor develops its full capacity; thus, deformation and possible tension cracking of the slope are minimized. Long-term corrosion protection of the anchors must be provided.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-7728bf3 elementor-widget elementor-widget-image\" data-id=\"7728bf3\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"620\" height=\"449\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/1_anchors_prim.jpg\" class=\"attachment-large size-large wp-image-2964\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/1_anchors_prim.jpg 620w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/1_anchors_prim-300x217.jpg 300w\" sizes=\"(max-width: 620px) 100vw, 620px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 1: schematic view of an anchored system (from www.prim.net)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-5c78329 elementor-widget elementor-widget-text-editor\" data-id=\"5c78329\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">Length of bars or cables can vary from few meters to several tens of meters. Rock bolts are commonly used to reinforce the surface and near-surface rock of the slope. Tendon and cable anchors are used for supporting large masses of unstable rock and are accordingly longer than rock bolts. Short reinforcing bars fully grouted into the rock mass are commonly called dowels. Their action is somewhat similar to rock bolts.<\/span><\/p><p>The rock bolt exerts a compressive force, which tends to prevent elastic rebound, frost action phenomena, and general relaxation or exfoliation by keeping the rock in its original position. Shear resistance along discontinuities is improved. Rock bolts are often used to minimize the decompression or loosening effects associated with recently excavated rock slopes. Figure 2 shows a group of large diameter bolts concentrated on an area at the base of a slope to maintain the integrity of large fault blocks.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-0af0bb2 elementor-widget elementor-widget-image\" data-id=\"0af0bb2\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"492\" height=\"314\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_rock-bolts_trb.jpg\" class=\"attachment-large size-large wp-image-2969\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_rock-bolts_trb.jpg 492w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_rock-bolts_trb-300x191.jpg 300w\" sizes=\"(max-width: 492px) 100vw, 492px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 2: Concentration of 3,5 cm diameter rock bolts at base of section at Hell\u2019s Gate Bluffs, British Columbia. Rock bolts were tensioned to 72 KN and dropped to 623 kN and then grouted (from TRB, 1978)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-14a0efb elementor-widget elementor-widget-image\" data-id=\"14a0efb\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"347\" height=\"488\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/3_anchors_besson-e1605176318833.jpg\" class=\"attachment-large size-large wp-image-2974\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/3_anchors_besson-e1605176318833.jpg 347w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/3_anchors_besson-e1605176318833-213x300.jpg 213w\" sizes=\"(max-width: 347px) 100vw, 347px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 3: Cliff reinforcement with passive system, Grenoble, Is\u00e8re, France (from Besson, 2005)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-37c2b20 elementor-widget elementor-widget-text-editor\" data-id=\"37c2b20\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">&#8211; External support systems<\/span><\/p><p>They offer resistance to loads imposed by the slope-forming materials.<br \/>Buttresses and bulkheads are designed to take part of the weight of the slope, thus inducing stable conditions and preventing rock falls. They are used for stabilization where failure of overhangs appears to be imminent or where slight cracking or vertical displacement appears to be occurring. Buttresses are usually constructed at highway or railway level.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-74a4aed elementor-widget elementor-widget-image\" data-id=\"74a4aed\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"333\" height=\"457\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/4_buttress_trb.jpg\" class=\"attachment-large size-large wp-image-2981\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/4_buttress_trb.jpg 333w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/4_buttress_trb-219x300.jpg 219w\" sizes=\"(max-width: 333px) 100vw, 333px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">igure 4 shows a 15 m high reinforced concrete buttress providing stabilization of a large overhanging slope (from TRB, 1978).<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-194955a elementor-widget elementor-widget-text-editor\" data-id=\"194955a\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">Retaining walls are used to prevent large blocks in the slope from failing and to control or correct failures by increasing the resistance to slope movements. The space along railways and highways is often too narrow for normal gravity walls, but tied-back walls may be used to overcome this problem. They need only have the strength required for bending and shear resistance between rock bolts. Figure 5 shows an application of a tieback retaining wall formed of galvanized steel members for protection of a high sedimentary road cut.<\/span><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-14a89d7 elementor-widget elementor-widget-image\" data-id=\"14a89d7\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1019\" height=\"406\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/5_retaining-wall_trb.jpg\" class=\"attachment-large size-large wp-image-2986\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/5_retaining-wall_trb.jpg 1019w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/5_retaining-wall_trb-300x120.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/5_retaining-wall_trb-768x306.jpg 768w\" sizes=\"(max-width: 1019px) 100vw, 1019px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 5 : Galvanized sheet steel retaining wall that is anchored by shallow rock bolts to prevent failures of high cut slope in sedimentary rock above highway in Hamilton, Ontario (from TRB, 1978)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-9402154 elementor-widget elementor-widget-text-editor\" data-id=\"9402154\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">The box gabion catch wall is a rectangular basket divided by diaphragms into smaller rectangles that are filled with stones. The basket is formed of hexagonal steel galvanized wire mesh. The wire mesh tends to reinforce the stone in tension. The gabion is a flexible structure that tends to deflect and deform instead of breaking by rock impact. Gabion catch walls are recognized as a feasible alternative to more rigid concrete walls for protecting the roads from rolling stones as large as 0,6 to 1 meter.<\/span><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-f257c46 elementor-widget elementor-widget-image\" data-id=\"f257c46\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"480\" height=\"309\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/6_gabion_slosson.jpg\" class=\"attachment-large size-large wp-image-2991\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/6_gabion_slosson.jpg 480w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/6_gabion_slosson-300x193.jpg 300w\" sizes=\"(max-width: 480px) 100vw, 480px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 6: Schematic view of a gabion catch wall (from Slosson and al., 1992)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-fd67391 elementor-widget elementor-widget-image\" data-id=\"fd67391\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"535\" height=\"383\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/7.gabion_trb1.jpg\" class=\"attachment-large size-large wp-image-2997\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/7.gabion_trb1.jpg 535w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/7.gabion_trb1-300x215.jpg 300w\" sizes=\"(max-width: 535px) 100vw, 535px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 7: Gabion catch wall along edge of high slope in unconsolidated material on main highway (from TRB, 1978)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-0163ade elementor-widget elementor-widget-image\" data-id=\"0163ade\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"347\" height=\"480\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/8_massif-btonn_besson.jpg\" class=\"attachment-large size-large wp-image-3002\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/8_massif-btonn_besson.jpg 347w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/8_massif-btonn_besson-217x300.jpg 217w\" sizes=\"(max-width: 347px) 100vw, 347px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 8: Cliff reinforcement with a combination of concrete buttress and gabion catch wall, Peyrolles, Bouches-du-Rh\u00f4ne, France (from Besson, 2005)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-268a4f7 elementor-widget elementor-widget-text-editor\" data-id=\"268a4f7\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">&#8211; Shotcrete<\/span><\/p><p>It is a concrete that consists of mortar with aggregate and that is projected by air jet directly onto the surface to be treated. It is used to prevent weathering and spalling of rock surfaces and to provide surface reinforcement between blocks. The shotcrete acts as a protective membrane on the surface of the rock and helps to maintain the adjacent rock blocks in place by mean of its initial shear and tensile strength. Shotcrete can be used in combination with steel wire mesh and rock bolts to give structural support and also to form buttresses for small loads (figure 9).<\/p><p>The most important advantage of shotcrete in treating rock slopes is that offers a rapid, mechanized and often uncomplicated solution to rock fall problems. Deterioration of shotcrete can result from frost action, groundwater seepage, or rock spalling due to lack of shotcrete bond.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-a7b18fd elementor-widget elementor-widget-image\" data-id=\"a7b18fd\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"488\" height=\"347\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/9_bton-projet_besson.jpg\" class=\"attachment-large size-large wp-image-3008\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/9_bton-projet_besson.jpg 488w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/9_bton-projet_besson-300x213.jpg 300w\" sizes=\"(max-width: 488px) 100vw, 488px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 9: Shotcrete in combination with steel wire net, Vinay, Is\u00e8re, France (from Besson, 2005)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-f52faed elementor-widget elementor-widget-text-editor\" data-id=\"f52faed\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">&#8211; Rock face purge<\/span><\/p><p>Instable rock or fall is artificially caused. The aim is to obtain a bare rock face and thus to eliminate fall risks. Different techniques are used to cause the fall, such as mining, chemical grout into boreholes, hydraulic breaking out, etc. Purge is a temporary protection technique because the bare rock will be submitted to fragmentation phenomena, frost action, and will be more liable to fall again. Therefore, rock face purge requires regular monitoring.<\/p><p>B. Passive techniques:<\/p><p>&#8211; Intercepting slop ditches and shaped berms<\/p><p>Slope ditches are used to intercept rock falls partway up the slope. Shaped berms are used at the top of the slope or can be installed in combination with a ditch. These methods ensure that rock falls get caught while they are on their way down the slope. The shaped berm is generally 4-6 m high, material (soil) is compressed and upstream face is often reinforced with gabions or tyres (figure 10). Depending of the nature of the terrain, ditches and berms are generally simple to construct and easy to maintain. An intercepting slope ditch should only be installed on a slope that can accept the introduction of a ditch without the stability of the entire slope being impaired.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-d33545f elementor-widget elementor-widget-image\" data-id=\"d33545f\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"628\" height=\"507\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/10_ditch_berm_prim.jpg\" class=\"attachment-large size-large wp-image-3013\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/10_ditch_berm_prim.jpg 628w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/10_ditch_berm_prim-300x242.jpg 300w\" sizes=\"(max-width: 628px) 100vw, 628px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 10: Schematic view of a slope ditch in combination with a shaped berm (from www.prim.net)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-30becda elementor-widget elementor-widget-image\" data-id=\"30becda\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"586\" height=\"384\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/11_ditch_nrc.jpg\" class=\"attachment-large size-large wp-image-3018\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/11_ditch_nrc.jpg 586w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/11_ditch_nrc-300x197.jpg 300w\" sizes=\"(max-width: 586px) 100vw, 586px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 11: This scheme shows a successful example of rock fall hazard mitigation with ditch and berm in Vail, Colorado. The ditch and berm were designed with the aid of a rock fall simulation software developed by university researchers (from NRC, 2004)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-1b0e909 elementor-widget elementor-widget-image\" data-id=\"1b0e909\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"517\" height=\"346\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/12_merlon_irma.jpg\" class=\"attachment-large size-large wp-image-3023\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/12_merlon_irma.jpg 517w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/12_merlon_irma-300x201.jpg 300w\" sizes=\"(max-width: 517px) 100vw, 517px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 12: Housing protection with shaped berm, Lumbin, Is\u00e8re, France (from www.irma-grenoble.com)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-d904dcc elementor-widget elementor-widget-image\" data-id=\"d904dcc\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"560\" height=\"340\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/13_merlon2_irma.jpg\" class=\"attachment-large size-large wp-image-3029\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/13_merlon2_irma.jpg 560w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/13_merlon2_irma-300x182.jpg 300w\" sizes=\"(max-width: 560px) 100vw, 560px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 13: Aerial view of a rockfall protection system with shaped berm (red colour), Crolles, Is\u00e8re, France (from www.prim.net)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-8719f2a elementor-widget elementor-widget-text-editor\" data-id=\"8719f2a\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">&#8211; Anchored wire mesh<\/span><\/p><p>It is a versatile and economical material for use in protecting the right-of-way from small rocks. Layers of mesh are often pinned onto the rock surface and installed as a drapery to prevent small loose rocks from becoming dislodged. They also can be used to guide falling rocks into a ditch at the base of the slope. This practice is commonly used on talus slopes in steep mountainous terrain. Mesh can be combined with long rock bolts to provide a generally deeper reinforcement. Conditions for the use of mesh are particularly suitable if no individual rocks are larger than 0,6 to 1 meter and if the slope is uniform enough for the mesh to be in almost continuous contact with the slope.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-766c49e elementor-widget elementor-widget-image\" data-id=\"766c49e\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"478\" height=\"580\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/14_mesh_trb-e1605177171747.jpg\" class=\"attachment-large size-large wp-image-3036\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/14_mesh_trb-e1605177171747.jpg 478w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/14_mesh_trb-e1605177171747-247x300.jpg 247w\" sizes=\"(max-width: 478px) 100vw, 478px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 14: Anchored double-twist, hexagonal wire mesh being draped f on a high rock face to prevent rock falls onto highway (from TRB, 1978)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-abde5c7 elementor-widget elementor-widget-image\" data-id=\"abde5c7\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"481\" height=\"572\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/15_mesh2_trb-e1605177333793.jpg\" class=\"attachment-large size-large wp-image-3041\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/15_mesh2_trb-e1605177333793.jpg 481w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/15_mesh2_trb-e1605177333793-252x300.jpg 252w\" sizes=\"(max-width: 481px) 100vw, 481px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 15: Wire mesh blanket used to control rock falls near Kelso, Washington. Falling rocks roll down surface of slope under mesh and drop into ditch (from TRB, 1978)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-2da6b56 elementor-widget elementor-widget-image\" data-id=\"2da6b56\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"516\" height=\"349\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/16_grenoble_irma.jpg\" class=\"attachment-large size-large wp-image-3046\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/16_grenoble_irma.jpg 516w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/16_grenoble_irma-300x203.jpg 300w\" sizes=\"(max-width: 516px) 100vw, 516px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 16: Wire mesh being draped on the \u201cBastille\u201d rock face to prevent rock falls onto buildings, Grenoble, Is\u00e8re, France, 2007 (www.irma-grenoble.com)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-4b26f41 elementor-widget elementor-widget-text-editor\" data-id=\"4b26f41\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">Anchored wire mesh can be installed at toe of rock face or on the slope and not only as a drapery onto the rock surface. They aimed at dissipating the kinetic energy of the rolling rocks and stopping their trajectory.<\/span><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-25053c7 elementor-widget elementor-widget-image\" data-id=\"25053c7\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"492\" height=\"316\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/17_pont-en-royans_irma.jpg\" class=\"attachment-large size-large wp-image-3052\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/17_pont-en-royans_irma.jpg 492w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/17_pont-en-royans_irma-300x193.jpg 300w\" sizes=\"(max-width: 492px) 100vw, 492px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 17: Anchored wire mesh to protect buildings against rock falls, Pont-en-Royans, Is\u00e8re, France, 2004 (from www.irma-grenoble.com)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-de18501 elementor-widget elementor-widget-image\" data-id=\"de18501\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"494\" height=\"368\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/18_cable-mesh_irma.jpg\" class=\"attachment-large size-large wp-image-3057\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/18_cable-mesh_irma.jpg 494w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/18_cable-mesh_irma-300x223.jpg 300w\" sizes=\"(max-width: 494px) 100vw, 494px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 18: Anchored wire mesh, France (from www.prim.net)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-8f843a8 elementor-widget elementor-widget-image\" data-id=\"8f843a8\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"496\" height=\"327\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/19_fence_irma.jpg\" class=\"attachment-large size-large wp-image-3062\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/19_fence_irma.jpg 496w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/19_fence_irma-300x198.jpg 300w\" sizes=\"(max-width: 496px) 100vw, 496px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 19: Anchored wire mesh, Venosc, Is\u00e8re, France, 2004 (from www.irma-grenoble.com)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-b4a42d2 elementor-widget elementor-widget-image\" data-id=\"b4a42d2\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"200\" height=\"150\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/20_high-impact-fences.jpg\" class=\"attachment-large size-large wp-image-3067\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 20 shows high-impact rock catchment fencing, engineered to catch large blocks travelling at high speeds (USA). This \u201ccable wall\u201d consists of steel posts set in concrete, cables strung horizontally between, and smaller cables between the cables to form a net (from www.prometheusconstruction.com).<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-6642346 elementor-widget elementor-widget-text-editor\" data-id=\"6642346\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">&#8211; Rigid fences<\/span><\/p><p>Rail walls consist of vertical posts and horizontal members that are extended between the vertical posts. The posts are usually scrap steel rails set in holes backfilled with concrete. The horizontal members are either ties or scrap rails. These rigid protection systems are generally less efficient than flexible screen such as wire mesh.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-47c89e2 elementor-widget elementor-widget-image\" data-id=\"47c89e2\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"483\" height=\"332\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/21_rail-wall_trb.jpg\" class=\"attachment-large size-large wp-image-3073\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/21_rail-wall_trb.jpg 483w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/21_rail-wall_trb-300x206.jpg 300w\" sizes=\"(max-width: 483px) 100vw, 483px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 21: Rail wall with vertical posts seated in cast-in-place footings and horizontal scrap rails cut into 3 to 4 meters lengths. The top of the wall is anchored by cables to bedrock for support (from from TRB, 1978)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-8333424 elementor-widget elementor-widget-text-editor\" data-id=\"8333424\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">&#8211; Role of forest<\/span><\/p><p>Vegetation has positive and negative effects on slope stability (More information on landslide causes). Within the framework of fall risk prevention, forest can act as a natural barrier to intercept rolling rocks.<\/p><p>A team of researchers of Grenoble, in France, is currently working about the protection function of forest against rock fall hazard. Different in situ experiments are led to reconstruct natural rock fall and rocks trajectory. Trajectory modelling will be developed, in order to be used by local practitioners.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-1953795 elementor-widget elementor-widget-image\" data-id=\"1953795\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"571\" height=\"394\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/22_fort-protection_cemagref.jpg\" class=\"attachment-large size-large wp-image-3079\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/22_fort-protection_cemagref.jpg 571w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/22_fort-protection_cemagref-300x207.jpg 300w\" sizes=\"(max-width: 571px) 100vw, 571px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 22: In situ rock fall experiment, Haute-Savoie, France (from www.grenoble.cemagref.fr)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-4737ba0 elementor-widget elementor-widget-text-editor\" data-id=\"4737ba0\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">First studies showed that for a slope between 25 and 35\u00b0, forest plays an important protection role, stopping 80 % of rocks. Protection effect of forest acts on stop distance and bounce height of rocks. An experiment has been led with a 3 tons boulder rolling at 80 km\/h with 2,5 meters high bounces. Forest stopped the boulder 80 meters further. Researches are also led with different tree species. Such studies contribute to develop long-term strategies for natural hazards prevention.<\/span><\/p><p><strong>References:<\/strong><br \/>&#8211; BESSON L., 2005. Les risques naturels: de la connaissance pratique \u00e0 la gestion administrative. Editions Techni. Cit\u00e9s, Voiron, 60 p.<br \/>&#8211; BRUNSDEN D., PRIOR D., 1984. Slope instability. John Wiley &amp; Sons Ltd, Chichester<br \/>&#8211; DIKAU R., BRUNSDEN D., SCHROTT L. &amp; IBSEN M.-L. (eds.), 1996. Landslide Recognition: Identification, Movement and Causes. John Wiley &amp; Sons Ltd, Chichester<br \/>&#8211; MATE, METL, 1997. Plans de pr\u00e9vention des risques naturels pr\u00e9visibles (PPR). Guide g\u00e9n\u00e9ral. La Documentation fran\u00e7aise, Paris, 76 p.<br \/>&#8211; NATIONAL RESEARCH COUNCIL, 2004. Partnerships for reducing landslide risk. Assessment of the landlide hazards mitigation strategy. The National academies press, Washington DC<br \/>&#8211; SLOSSON E., KEENE A.G., JOHNSON J.A., 1992. Landslides\/Landslide mitigation. In: Reviews of Engineering Geology, Volume IX, Colorado<br \/>&#8211; TRANSPORTATION RESEARCH BOARD, 1978. Landslides: Analysis and Control. National Academy of Sciences, Special Report 176, Washington DC<\/p><p><strong>Websites:<\/strong><br \/><a href=\"http:\/\/www.irma-grenoble.com\/\" target=\"_blank\" rel=\"noopener\">www.irma-grenoble.com<\/a><br \/><a href=\"http:\/\/www.prim.net\/\" target=\"_blank\" rel=\"noopener\">www.prim.net<\/a><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p>\n<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-1922\" class=\"elementor-tab-title\" data-tab=\"2\" role=\"tab\" aria-controls=\"elementor-tab-content-1922\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">9.2. Flow prevention and protection<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-1922\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"2\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-1922\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"3085\" class=\"elementor elementor-3085\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-aec81fb elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"aec81fb\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-4b373dd\" data-id=\"4b373dd\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-6148596 elementor-widget elementor-widget-text-editor\" data-id=\"6148596\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Techniques of prevention<br \/><br \/>Flows processes analysis is complex because it concerns both geotechnics, geomorphology domains (as for landslides in general) and hydraulics domain. Thus, prevention and protection techniques must also concern these different domains.<br \/>Flow triggering is mainly caused by heavy rainfalls; prevision of rain falls events is possible thanks to predictive models, however they concern large areas and not small watersheds in which flows occur. Moreover, flows events are characterized by the rapidity with which they propagate in response to a rain fall event. Thus, prediction of flow events is difficult or even impossible.<br \/>The best way for flow prevention as for landslides in general is to control urbanization by a zoning map which defines terrains which can be built or not, according to the degree of flow hazard and vulnerability (see more information on landslide mapping).<br \/><br \/>Moreover, prevention techniques consist in regularly maintaining the main channel and the banks in order to avoid blocking of the channel by trees for example, liable to aggravate the consequences of the flow.<br \/><br \/>Techniques of protection<br \/>A flow is generated because of a great quantity of material is available for sediment transport on the slopes of the watershed. According to this, techniques of protection can be classified in two distinct categories:<br \/>&#8211; \u201cActive techniques\u201d: they avoid the triggering of the flow. They mainly consist in reducing sediment transport by acting on source areas, by reducing slope erosion processes.<br \/>&#8211; \u201cPassive techniques\u201d: they seek to control the consequences of the flow. They mainly consist in slowing down the flow by acting on the stream channel.<br \/><br \/>A. Active techniques<br \/><br \/>&#8211; Role of vegetation<br \/><br \/>It is admitted by scientific community that vegetation acts on slopes by reducing runoff and erosion processes. Planting is considered as a long-term and efficient strategy for preventing sediment production. From the end of the 19th century large reforestation works have been carried out in French mountainous areas in order to reduce the frequency of mud flows and debris flows. For example, 1000 ha have been planted on highly erodable slopes of the Riou-Bourdoux catchment, in the Barcelonnette Basin. Even if the torrential activity did nit disappear, the frequency of flows rapidly decreased (figure 1).<br \/><br \/><br \/><br \/><br \/>Fig. 1: Evolution of the forests surfaces between 1896 (a) and 2000 (b) in the Riou-Bourdoux catchment (from Delsigne and al., 2001)<br \/><br \/><br \/>A technique is to build at different levels in the slope banks with wire mesh in order to reduce runoff and improve planting of herbaceous species or shrubs. These banks can also be made off wooden posts (figure 2).<br \/><br \/><br \/><br \/><br \/><br \/>Fig. 2: Slope planting with banks in Is\u00e8re, France. Evolution of the slope between 1898 (a), 1912 (b), 1988 (c) (from Besson, 2005)<br \/><br \/>&#8211; Correction works in gullies<br \/>In order to prevent gullying and erosion processes, small dams can be built across the gullies in combination with planting. These dams can be made of concrete, gabions, grids, geosynthetics or wire mesh anchored by steel or wooden posts (figure 3).<br \/><br \/><br \/><br \/>Figure 3: Gullies correction with wire mesh small dams (from Besson, 2005)<br \/><br \/><br \/><br \/>B. Passive techniques<br \/><br \/>While active techniques rather correspond to bio-engineering (planting techniques), passive techniques rather correspond to civil engineering.<br \/><br \/>&#8211; Stabilization dams in the stream channel<br \/>These works aim at stabilizing the river profile. Indeed a stream tends to erode its banks and bed in steep slopes and to deposit material in gentle slopes in order to reach an equilibrium profile. Therefore, the upstream part of the channel tends to recede.<br \/>Torrential correction consists in building dams in the cross section of the channel in order to attenuate energy of the flow and provoke deposit of material upstream each dam. The purposes are to reduce erosion of the channel and quantity of material reaching the alluvial cone and liable to damage the human infrastructures. The dams also allow stabilization of the banks (figure 4).<br \/>Sizing of the dams requires for the planner to consider hydraulic behaviour of the stream, natural equilibrium slope of the channel and sediment transport processes. Dams must be frequently maintained because they can be damaged by major flows (figures 5 and 6).<br \/><br \/><br \/>Fig. 4: Correction of a stream profile with dams. a: natural profile which tends to retreat by erosion process (1 to 4). b: stabilized profile with dams (from Besson, 2005)<br \/><br \/><br \/><br \/><br \/><br \/><br \/><br \/><br \/><br \/><br \/><br \/>Fig. 5: Dams in the Faucon stream, Barcelonnette Basin, France (from Rema\u00eetre, 2006)<br \/><br \/><br \/><br \/><br \/><br \/><br \/>Fig. 6: Damaged dam in the Faucon stream (from Rema\u00eetre, 2006)<br \/><br \/><br \/><br \/><br \/><br \/><br \/><br \/><br \/><br \/><br \/>&#8211; Deposit area\/sediment trap<br \/><br \/>It aims at slowing down the flow and provoking deposit of the materials.<br \/><br \/>&#8211; Dykes<br \/><br \/>It aims at protecting the banks from erosion and preventing the flow from overflowing. It usually consists of reinforced concrete walls or gabions walls. Anchor of the wall must be carefully designed in order to prevent erosion at the bottom of the wall.<br \/><br \/><br \/>References:<br \/><br \/>BESSON L., 2005. Les risques naturels: de la connaissance pratique \u00e0 la gestion administrative. Editions Techni. Cit\u00e9s, Voiron, 60 p.<br \/>DELSIGNE F., LAHOUSSE P., FLEZ C., GUITER G., 2001. Le Riou Bourdoux :un \u00ab monstre \u00bb alpin sous haute surveillance. Revue Foresti\u00e8re Fran\u00e7aise, p.527-540<br \/>REMAITRE A., 2006. Morphologie et dynamique des laves torrentielles : Applications aux torrents des Terres Noires du bassin de Barcelonnette (Alpes du Sud). PhD Thesis: Laboratoire Geophen, Universit\u00e9 de Caen\/Basse-Normandie, 487 p.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p>\n<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-1923\" class=\"elementor-tab-title\" data-tab=\"3\" role=\"tab\" aria-controls=\"elementor-tab-content-1923\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">9.3. More information on subsidence prevention and protection<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-1923\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"3\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-1923\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"3089\" class=\"elementor elementor-3089\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-f811eff elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"f811eff\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-d9cb32e\" data-id=\"d9cb32e\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-fb39a1d elementor-widget elementor-widget-text-editor\" data-id=\"fb39a1d\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Methods and techniques of prevention and repairing of the damages due to slow subsidence are the same of rapid subsidence.<\/p><p>Prevention of subsidence, as for landslides in general, corresponds to a step comprising several successive stages sometimes requiring adapted techniques to seek cavities (C\u00f4te et al., 2005 ; Poth\u00e9rat, 2005). The following stages are classically retained:<\/p><p>1. Preliminary recognition allows an identification of the sectors prone to subsidence. This step comprises:<\/p><p>(a) a preliminary stage consisting of a geological expertise to identify the grounds prone to dissolution (natural cavities) or exploitation (anthropogenic cavities). Information is then completed by an investigation of archives, ancient maps and plans, interviews (population and organizations), etc. In France, there exists a national database on underground cavities \u201cBDCavit\u00e9\u201d;<\/p><p>(b) a research of surface indices by using remote sensing techniques such as photo-interpretation of vertical or oblique photographs, infrared thermic radiometry, accomplished with ground validation (research of morphological indices, etc.)<\/p><p>2. Detection of the voids starting from a selection of specific hazard zones (achieved in stage 1), to precisely locate voids and decompressing zones (surfaces and volume) by:<\/p><p>(a) sub surface geophysical methods: microgravimetry to obtain a map of geophysical anomalies, and other seismic or electromagnetic methods, ,.<\/p><p>(b) drillings with instantaneous or differed diagraphs (??) and videoscopy in drillings,<\/p><p>(c) exploration, if accessible, and cartography.<\/p><p>3. Interpretation, monitoring and hazard assessment.<\/p><p>4. Identification of elements at risks and assessment of their vulnerability<\/p><p>5. Risk mapping (in 3-4 levels).<\/p><p>Main techniques of protection are classified in two distinct categories (MEDD, 2004):<\/p><p>A. \u2018active techniques\u2019 to avoid the triggering of the movement. They consist in supporting and consolidating the cavities to avoid subsidence. For instance, it is possible to reinforce existing pillars or to reduce the distance between the pillars:<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-2d47329 elementor-widget elementor-widget-image\" data-id=\"2d47329\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"719\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/1_scheme_confortement_-subsidence1-1024x719.jpg\" class=\"attachment-large size-large wp-image-3103\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/1_scheme_confortement_-subsidence1-1024x719.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/1_scheme_confortement_-subsidence1-300x211.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/1_scheme_confortement_-subsidence1-768x539.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/1_scheme_confortement_-subsidence1-1536x1078.jpg 1536w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/1_scheme_confortement_-subsidence1-2048x1437.jpg 2048w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-6d661eb elementor-widget elementor-widget-text-editor\" data-id=\"6d661eb\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>&#8211; by arranging additional pillars, by the construction of new pillars in masonry in the accessible cavities or a grouting (mixture of concrete and additives) forming studs in the inaccessible cavities (with 1: pile; 2: natural or artificial caves; 3: grouting forming stud; 4: pillar in masonry).<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-b39df45 elementor-widget elementor-widget-image\" data-id=\"b39df45\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"730\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_scheme_confortement_-subsidence2-1024x730.jpg\" class=\"attachment-large size-large wp-image-3098\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_scheme_confortement_-subsidence2-1024x730.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_scheme_confortement_-subsidence2-300x214.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_scheme_confortement_-subsidence2-768x547.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_scheme_confortement_-subsidence2-1536x1095.jpg 1536w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_scheme_confortement_-subsidence2-2048x1459.jpg 2048w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-14b72cc elementor-widget elementor-widget-text-editor\" data-id=\"14b72cc\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>&#8211; by filling the cavity by thorough fill (if it is accessible) or by gravitating injection of liquid mortar (generally, mixture of sand, bentonite and additives) after installation of containment walls (with 1: pile; 2: natural or artificial caves; 5: liquid mortar forming containment wall; 6: filling liquid mortar; 7: injection drill).<\/p><p>If the cavity is close to the surface, it is essential to control the water infiltrations which could accentuate the phenomenon<\/p><p><br \/>B \u2018passive techniques\u2019 which seek to control the consequences of subsidence. They aim at reinforcing the structures of threatened constructions (by peripheral chaining, etc.) so that they do not undergo the consequences of the relative settlements. The realization of deep foundations, crossing the cavity, can be a means of protecting. Lastly, the buried networks must be flexible to adapt to the deformations (regular controls of their sealing must be envisaged).<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-d07cbc2 elementor-widget elementor-widget-image\" data-id=\"d07cbc2\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"712\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/3_scheme_confortement_-subsidence3-1024x712.jpg\" class=\"attachment-large size-large wp-image-3092\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/3_scheme_confortement_-subsidence3-1024x712.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/3_scheme_confortement_-subsidence3-300x209.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/3_scheme_confortement_-subsidence3-768x534.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/3_scheme_confortement_-subsidence3-1536x1068.jpg 1536w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/3_scheme_confortement_-subsidence3-2048x1424.jpg 2048w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-d2e0272 elementor-widget elementor-widget-text-editor\" data-id=\"d2e0272\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Realization of deep foundations (i.e. concrete piles), crossing the cavity, can be a means of protecting (with 1: pile; 2: natural or artificial caves; 8: casing for protection against alteration)<br \/>\u00a0<\/p><p><strong>References<\/strong><br \/>C\u00f4te, PH., fauchard, C., Poth\u00e9rat, P. (2005). M\u00e9thodes g\u00e9ophysiques pour la localisation de cavit\u00e9s souterraines : potentialit\u00e9s et limites. In Evaluation et gestion des risques li\u00e9s aux carri\u00e8res souterraines abandonn\u00e9es. Actes des journ\u00e9es scientifiques du LCPC, pp. 8-17.<br \/>Embleton, C., and Embleton C. (eds.) (1997), Geomorphological Hazards of Europe. Developments in Earth Surface Processes 5. Amsterdam : Elsevier, 524p.<br \/>Flageollet, J. C. (1988), Les mouvements de terrain et leur pr\u00e9vention, Paris : Masson, 224p.<br \/>LCPC (2000). Guide technique pour la caract\u00e9risation et cartographie de l\u2019al\u00e9a d\u00fb aux mouvements de terrain. Collection \u2018les risques naturels\u2019. Laboratoire Central des Ponts et Chauss\u00e9es, 91 p.<br \/>Maquaire, O., (2005). Geomorphic hazards and natural risks, In: Koster, E., A. (ed.), The Physical Geography of Western Europe, Oxford Regional Environments, Oxford University Press, Chapter 18, 354-377.<br \/>Minist\u00e8re de l\u2019Environnement, 1997, Plans de pr\u00e9vention des risques naturels (PPR) : guide g\u00e9n\u00e9ral.. La Documentation Fran\u00e7aise, Paris, 76p.<br \/>Minist\u00e8re de l\u2019Environnement, 1999, Plans de pr\u00e9vention des risques naturels (PPR) : risques de mouvements de terrain. Guide m\u00e9thodologique.. La Documentation Fran\u00e7aise, Paris, 71p.<br \/>Minist\u00e8re de l\u2019Ecologie et du D\u00e9veloppement Durable, 2004. Dossier d\u2019information sur le risque Mouvement de terrains, 20 p. (\u00e0 t\u00e9l\u00e9charger sur site du MEDD).<br \/>Poth\u00e9rat, P. (2005). L\u2019op\u00e9ration de recherche \u00ab Carri\u00e8res souterraines abandonn\u00e9es \u00bb. Localisation, dignostic de stabilit\u00e9, gestion. Rapport de synth\u00e8se. G\u00e9otechnique et risques naturels, GT 77. LCPC, 132 p.<\/p><p><strong>Websites:<\/strong><br \/><a href=\"http:\/\/fr.wikipedia.org\/wiki\/Subsidence\" target=\"_blank\" rel=\"noopener\">http:\/\/fr.wikipedia.org\/wiki\/Subsidence<\/a><br \/><a href=\"http:\/\/www.lorraine.drire.gouv.fr\/mines\/g_cadreDomaine.asp?droite=2_ApresMines.asp&amp;bas=g_MinesNavig.asp?DEST=APMINES\" target=\"_blank\" rel=\"noopener\">http:\/\/www.lorraine.drire.gouv.fr\/mines\/g_cadreDomaine.asp?droite=2_ApresMines.asp&amp;bas=g_MinesNavig.asp?DEST=APMINES<\/a><br \/><a href=\"http:\/\/www.cgm.org\/themes\/soussol\/mines\/\" target=\"_blank\" rel=\"noopener\">http:\/\/www.cgm.org\/themes\/soussol\/mines\/<\/a><br \/><a href=\"http:\/\/www.cavite.net\/\" target=\"_blank\" rel=\"noopener\">http:\/\/www.cavite.net<\/a><br \/><a href=\"http:\/\/www.prim.net\/professionnel\/documentation\/dossiers_info\/nat\/low\/mouvtTerr.pdf\" target=\"_blank\" rel=\"noopener\">http:\/\/www.prim.net\/professionnel\/documentation\/dossiers_info\/nat\/low\/mouvtTerr.pdf<\/a><br \/><a href=\"http:\/\/www.catp-asso.org\/cavites37\/pages\/missions.htm\" target=\"_blank\" rel=\"noopener\">http:\/\/www.catp-asso.org\/cavites37\/pages\/missions.htm<\/a><br \/><a href=\"http:\/\/clamart.cyberkata.org\/\" target=\"_blank\" rel=\"noopener\">http:\/\/clamart.cyberkata.org\/<\/a><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p>\n<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-20810\" class=\"elementor-tab-title\" data-tab=\"10\" role=\"tab\" aria-controls=\"elementor-tab-content-20810\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">10. Est-il possible d\u2019att\u00e9nuer les cons\u00e9quences d\u2019un glissement de terrain ?<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-20810\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"10\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-20810\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"7937\" class=\"elementor elementor-7937 elementor-3109\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-c720155 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"c720155\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-3473f0d\" data-id=\"3473f0d\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-6d3de0b elementor-widget elementor-widget-text-editor\" data-id=\"6d3de0b\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Les cons\u00e9quences des glissements de terrain peuvent \u00eatre att\u00e9nu\u00e9es par des techniques de protection et de r\u00e9paration.<\/p>\n<p>Le risque qu\u2019un mouvement de terrain survienne peut \u00eatre r\u00e9duit et une protection assur\u00e9e par des mesures de pr\u00e9vention et de protection de deux types\u00a0:<\/p>\n<ul>\n<li><strong>protection active<\/strong>: vise les causes actives ou potentielles\u00a0; consiste le plus souvent en un drainage profond ou une reforestation\u00a0;<\/li>\n<li><strong>protection passive\u00a0<\/strong>:\u00a0vise \u00e0 contenir les mat\u00e9riaux en mouvement ou menac\u00e9s de d\u00e9stabilisation\u00a0; consiste g\u00e9n\u00e9ralement en des travaux de terrassement, de modification du relief ou de construction d\u2019ouvrages de sout\u00e8nement.<\/li>\n<\/ul>\n<p>En ce qui concerne les ph\u00e9nom\u00e8nes d\u2018affaissement, d\u2019effondrement et de retrait\/gonflement, deux types de techniques de r\u00e9paration et de pr\u00e9vention sont g\u00e9n\u00e9ralement utilis\u00e9es, en fonction de l\u2019efficacit\u00e9 souhait\u00e9e et des contraintes budg\u00e9taires\u00a0:<\/p>\n<ul>\n<li>m\u00e9thodes \u00ab\u00a0lourdes\u00a0\u00bb (co\u00fbteuses mais g\u00e9n\u00e9ralement efficaces) comme la consolidation d\u2019un ouvrage\u00a0menac\u00e9\u00a0;<\/li>\n<li>m\u00e9thodes \u00ab\u00a0l\u00e9g\u00e8res\u00a0\u00bb (moins co\u00fbteuses mais souvent insuffisantes) consistant en des travaux r\u00e9alis\u00e9s autour de l\u2019ouvrage.<\/li>\n<\/ul>\n<ul>\n<li>En cas de risque marqu\u00e9, de forte vuln\u00e9rabilit\u00e9 et si le niveau de risque ne peut \u00eatre r\u00e9duit, les pentes doivent \u00eatre surveill\u00e9es. Les mouvements et variations de la surface doivent \u00eatre enregistr\u00e9s en continu et d\u00e9clencher une alerte au-del\u00e0 d\u2019un seuil pr\u00e9d\u00e9fini.<\/li>\n<\/ul>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-0112921 elementor-widget elementor-widget-image\" data-id=\"0112921\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"766\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/DSCN7391PonteModino-1024x766.jpg\" class=\"attachment-large size-large wp-image-3114\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/DSCN7391PonteModino-1024x766.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/DSCN7391PonteModino-300x224.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/DSCN7391PonteModino-768x575.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/DSCN7391PonteModino-1536x1149.jpg 1536w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/DSCN7391PonteModino-2048x1532.jpg 2048w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Wire mesh blanket used to control rock falls at Ponte Modino (Modena Apennines)  (photo by D. Castaldini, February 2009)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-c24d676 elementor-widget elementor-widget-accordion\" data-id=\"c24d676\" data-element_type=\"widget\" data-widget_type=\"accordion.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<div class=\"elementor-accordion\" role=\"tablist\">\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-2031\" class=\"elementor-tab-title\" data-tab=\"1\" role=\"tab\" aria-controls=\"elementor-tab-content-2031\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">10.1 How the consequences of landslides can be mitigated<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-2031\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"1\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-2031\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"3121\" class=\"elementor elementor-3121\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-dcddd53 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"dcddd53\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-92cde40\" data-id=\"92cde40\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-0e23dc8 elementor-widget elementor-widget-text-editor\" data-id=\"0e23dc8\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Techniques of prevention<\/p><p>Prevention of slides, as for landslides in general, comprises several successive stages. First, investigations must be carried out in order to identify the sectors prone to slide. These investigations lead to slide hazard assessment. Then, elements at risk are identified and their vulnerability is assessed in order to include slide hazard in town planning. The result is a zoning map which defines terrains which can be built or not, according to the degree of hazard and vulnerability (go to 12.1.More information on landslide mapping). Therefore, the town is obliged to control all water discharge (drainage waters, waste waters, rain waters) and to avoid digging being liable to destabilize the slope.<\/p><p>Techniques of protection<\/p><p>These techniques are usually used for reducing small-scale slide hazards. In large-scale and very deep slides, in combination with protection techniques such as underground drainage, the best way is to continuously monitor the site and take urban planning measures.<\/p><p>Techniques of protection can be classified in two distinct categories:<br \/>&#8211; \u201cActive techniques\u201d: they avoid the triggering of the slide. They mainly consist in increasing the strength of the slope-forming material, by drainage or internal soil reinforcement systems.<br \/>&#8211; \u201cPassive techniques\u201d: they seek to control the consequences of the slide. They consist in external reinforcement systems which retain the material on the slope.<\/p><p>A. Active techniques<\/p><p>&#8211; Drainage techniques<\/p><p>Drainage of water is the most important operation for the correction of existing or potential slides. Drainage will both reduce the weight of the mass tending to slide, and increase the strength of the slope-forming material. Surface, subsurface and underground drainage techniques exist. Figure 1 show different drainage techniques used to stabilize a slope (from TRB, 1978).<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-f57559a elementor-widget elementor-widget-image\" data-id=\"f57559a\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"706\" height=\"410\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/1_drains.jpg\" class=\"attachment-large size-large wp-image-3126\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/1_drains.jpg 706w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/1_drains-300x174.jpg 300w\" sizes=\"(max-width: 706px) 100vw, 706px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 1: Different drainage techniques used to stabilize a slope (from TRB, 1978)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-60788ce elementor-widget elementor-widget-text-editor\" data-id=\"60788ce\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">Surface drainage is strongly recommended as part of the treatment for any slide or potential slide. Interceptor drains and drainage ditches collect and carry surface waters away from the instable slope. These systems provide a rapid surface drainage. A ditch is between 0,5 and 1 metre deep, with triangular, rectangular or trapezoidal section.<\/span><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-b1c89f3 elementor-widget elementor-widget-image\" data-id=\"b1c89f3\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"338\" height=\"227\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_ditch_besson.jpg\" class=\"attachment-large size-large wp-image-3131\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_ditch_besson.jpg 338w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_ditch_besson-300x201.jpg 300w\" sizes=\"(max-width: 338px) 100vw, 338px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 2: Network of ditches which converge to carry surface waters away from the instable slope (from Goueffon, 2005)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-5759130 elementor-widget elementor-widget-text-editor\" data-id=\"5759130\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">These methods to control surface runoff are effective when used in conjunction with subsurface and underground drainage techniques. It is agreed that groundwater constitutes the most important contributory cause for the majority of landslides (See\u00a0<\/span><a style=\"background-color: #ffffff; font-size: 1rem; text-align: left;\" href=\"http:\/\/www.besafenet.net\/en-gb\/natural-hazards-landslides#faq72\">3.1.1. More details on the role of water<\/a><span style=\"font-size: 1rem; text-align: left;\">). Thus, the most successful methods used for both prevention and correction of slides consist of entirely or partially groundwater control.<\/span><\/p><p>Draining trench is usually employed for subsurface drainage. The trench is 5-6 metres deep. A drain pipe perforated in its upper part is installed at the bottom of the trench. A membrane can be put, to prevent contact between backfill and surrounding material or to avoid clogging of the drain. Then, the trench is filled with pervious rock mixture, generally with clean granular material or pebbles. At the surface, the trench must include inspection holes to control functioning of the drainage system.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-d8b7d27 elementor-widget elementor-widget-image\" data-id=\"d8b7d27\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"348\" height=\"488\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/3.draining-trench_besson1.jpg\" class=\"attachment-large size-large wp-image-3136\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/3.draining-trench_besson1.jpg 348w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/3.draining-trench_besson1-214x300.jpg 214w\" sizes=\"(max-width: 348px) 100vw, 348px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 3: Draining trench construction (blue colour: drain pipe) (from Besson, 2005)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-740715f elementor-widget elementor-widget-text-editor\" data-id=\"740715f\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Finally, drainage waters must be collected and carry away from the unstable slope. Figure 4 shows an example of impervious collecting system.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-e5d6fe9 elementor-widget elementor-widget-image\" data-id=\"e5d6fe9\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"870\" height=\"654\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/4_water-collecting_besson.jpg\" class=\"attachment-large size-large wp-image-3141\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/4_water-collecting_besson.jpg 870w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/4_water-collecting_besson-300x226.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/4_water-collecting_besson-768x577.jpg 768w\" sizes=\"(max-width: 870px) 100vw, 870px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 4: Water collecting system, Avignonet, Is\u00e8re, France (from Besson, 2005)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-384fed5 elementor-widget elementor-widget-text-editor\" data-id=\"384fed5\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">Draining trench is not efficient in case of active landslide because it can break up and is insufficient for deep landslides. Underground drainage is necessary.<\/span><\/p><p>Underground drainage implies boreholes drilling. It consists of subhorizontal drains, when water table is too deep to be lowered with surface or subsurface drains. When the instable mass is deep and when the movement is slow (1cm\/year), vertical drains and pumped wells are used.<\/p><p>Underground drainage is more expensive and more difficult to accomplish than surface and subsurface drainage. Drilling operations must be carried out carefully, during dry seasons when the displacements are the slowest. Then, water table level and displacements must be monitored during one year at least.<\/p><p>Moreover, problems exist concerning subdrains: clogging by materials such as dispersive clays, cohesionless silts, or root system of dense vegetation. Rodents can also make homes of subdrain outlet pipes, or these pipes can become overgrown near their discharge point, causing the system to back up. Hard groundwater can deposit calcium carbonate around the percolation silts in subdrain pipes or well casings.<\/p><p>Finally, it is necessary to do geotechnical and hydrogeological studies before beginning the treatment, because the effectiveness and the frequency of use of the various types of drainage techniques vary according to the geology and the climatic conditions. That is why many practitioners prefer to use drainage in combination with other measures, such as retaining structures.<\/p><p>&#8211; Slope remodelling<\/p><p>Another method to stabilize a slope is remodelling. The principle is to remove the upper part of the slide by excavation and to buttress the toe of the slide by filling and compaction. This technique can be used during construction or stabilization of existing roadways slopes. But in case of natural terrains, this method is not efficient because the quantity of material necessary to remove is generally too important. However, shallow remodelling can be done.<\/p><p>&#8211; Role of vegetation<\/p><p>Vegetation has positive and negative effects on slope stability (<a href=\"http:\/\/www.besafenet.net\/en-gb\/natural-hazards-landslides#faq73\">3.1.2. More information on landslide causes&gt;&gt;<\/a>). In many cases, planting is considered as a long-term strategy for natural hazards prevention, more particularly for slide risk management. Figure 5 shows a good example of positive effect of the vegetation on slope stability. The root network of a banyan tree stabilizes a nearly vertical cut in colluvium on a trail at Diamond Head, Hawa\u00ef. Water percolating through the colluvium serves to propagate the expanding root system. The concept of reinforced earth (see below) emanates from this kind of natural process.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-3f6de1c elementor-widget elementor-widget-image\" data-id=\"3f6de1c\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"341\" height=\"244\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/5_root-system.jpg\" class=\"attachment-large size-large wp-image-3146\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/5_root-system.jpg 341w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/5_root-system-300x215.jpg 300w\" sizes=\"(max-width: 341px) 100vw, 341px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 5: Stabilization of a slope by the root system of a banyan tree, Hawa\u00ef (from Slosson and al., 1992)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-8ecaa31 elementor-widget elementor-widget-text-editor\" data-id=\"8ecaa31\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">&#8211; Soil reinforcement using Geogrid<\/span><\/p><p>Geogrid is usually used during the construction of embankments near highways, or to repair existing landslides. It corresponds to the concept of reinforced earth. The principle is to provide tensile reinforcement through frictional contact with the surrounding soil. Soil-reinforcing grids serve to increase the unit shear strength of any soil which they are placed, thereby offering much higher long-term factors of safety than are possible trough simple compaction.<\/p><p>The grids are an-open-mesh construction, usually composed of polypropylene or high-density polyethylene impregnated with carbon-black ultraviolet radiation inhibitors. The size of Geogrid depends on the level of intended loading once buried in the ground. Reinforcing grids are generally placed at lift separations of 0,6-1,2 metres. Embedment lengths generally vary from 1 to 1,5 times the slope height (figure 6). Soil is then spread over the mesh and compacted (figure 7). The area immediately adjacent to the free face usually requires local compaction with hand-operated vibratory equipment.<br \/>Wrapping the slope face with the grids is an option (figure 8 and 9). Face wrapping generally provides a mulch surface to resist erosion and promote planting. Vegetation serves to protect the grids from ultraviolet degradation and vandalism. It provides an aesthetic surface and also reduces erosion. Face wrapping also helps retard rodent burrowing into the slope.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-3dd4b71 elementor-widget elementor-widget-image\" data-id=\"3dd4b71\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"758\" height=\"902\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/6_geotextile_slosson.jpg\" class=\"attachment-large size-large wp-image-3151\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/6_geotextile_slosson.jpg 758w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/6_geotextile_slosson-252x300.jpg 252w\" sizes=\"(max-width: 758px) 100vw, 758px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 6: Schematic representation of slope reinforcement with Geogrid (from Slosson and al., 1992)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-908afca elementor-widget elementor-widget-image\" data-id=\"908afca\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"499\" height=\"339\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/7_geogrid_compaction.jpg\" class=\"attachment-large size-large wp-image-3156\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/7_geogrid_compaction.jpg 499w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/7_geogrid_compaction-300x204.jpg 300w\" sizes=\"(max-width: 499px) 100vw, 499px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 7: Compaction of fill lifts in a landslide repair between successive layers of Geogrid. Faces are wrapped (from Slosson and al., 1992)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-07af5fd elementor-widget elementor-widget-image\" data-id=\"07af5fd\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"412\" height=\"275\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/8_landslide-repair2.jpg\" class=\"attachment-large size-large wp-image-3161\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/8_landslide-repair2.jpg 412w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/8_landslide-repair2-300x200.jpg 300w\" sizes=\"(max-width: 412px) 100vw, 412px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-bca5bf8 elementor-widget elementor-widget-image\" data-id=\"bca5bf8\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"420\" height=\"273\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/9_landslide-repair.jpg\" class=\"attachment-large size-large wp-image-3166\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/9_landslide-repair.jpg 420w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/9_landslide-repair-300x195.jpg 300w\" sizes=\"(max-width: 420px) 100vw, 420px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-68e2e97 figure-caption elementor-widget elementor-widget-text-editor\" data-id=\"68e2e97\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p style=\"text-align: center;\"><em>Figures 8 and 9: Two views of a Geogrid-reinforced landslide repair accomplished in 1986 in Crockett, California. The lower view shows the finished slope six weeks after completion. The slope has be hydroseeded and Geogrid face acts as a good mulch mat (from Slosson and al., 1992)<\/em><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-abbc3e2 elementor-widget elementor-widget-text-editor\" data-id=\"abbc3e2\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">B. Passive techniques<\/span><\/p><p>A slope can be stabilized increasing the forces resisting the mass movement with an external applied force system. These systems usually apply a resisting force at the toe of the sliding mass. These are basically the same systems than employed for fall risk prevention: buttresses and bulkheads, retaining walls and box gabion catch walls (<a href=\"http:\/\/www.besafenet.net\/en-gb\/natural-hazards-landslides#faq64\">go to 2.1.2.2. more information on fall<\/a>).<\/p><p>The principle of the buttress is to provide sufficient dead weight near the toe of the unstable mass to prevent moment. A buttress design provides an additional resistance component near the toe of the slope to ensure an adequate safety factor against failure. Several important highway sections have been constructed with or treated remedially by a buttress.<\/p><p>Care must be taken in the construction phases to ensure adequate depth for founding the buttress and prescribed quality for the layer on which the buttress is placed.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-e0d9ede elementor-widget elementor-widget-image\" data-id=\"e0d9ede\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"557\" height=\"440\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/10_rock-buttress.jpg\" class=\"attachment-large size-large wp-image-3171\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/10_rock-buttress.jpg 557w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/10_rock-buttress-300x237.jpg 300w\" sizes=\"(max-width: 557px) 100vw, 557px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 10: Rock buttress used to control unstable slope (from TRB, 1978)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-287ffec elementor-widget elementor-widget-text-editor\" data-id=\"287ffec\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">Reinforced earth wall is a construction material that involves the use of backfill soil and thin metal strips to form a mass that is capable of restraining large imposed loads. The concept is about the same than Geogrid, but the final structure is an external wall. The face of a reinforced earth wall is usually vertical, and the backfill material is confined behind either metal of unreinforced concrete plates.<\/span><\/p><p>As a buttress, reinforced earth wall acts as a gravity structure placed on a stable foundation, and it must be designed to resist the slope driving forces (overturning, shearing internally, sliding at or below the base).<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-3dd63be elementor-widget elementor-widget-image\" data-id=\"3dd63be\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"536\" height=\"452\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/11_earth-wall.jpg\" class=\"attachment-large size-large wp-image-3176\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/11_earth-wall.jpg 536w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/11_earth-wall-300x253.jpg 300w\" sizes=\"(max-width: 536px) 100vw, 536px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 11: Reinforced earth wall used as a highway fill to ensure stability to sidehill (from TRB, 1978)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-0611339 elementor-widget elementor-widget-image\" data-id=\"0611339\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"484\" height=\"347\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/12_earth-wall-saverne.jpg\" class=\"attachment-large size-large wp-image-3181\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/12_earth-wall-saverne.jpg 484w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/12_earth-wall-saverne-300x215.jpg 300w\" sizes=\"(max-width: 484px) 100vw, 484px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 12: Reinforced earth wall, Saverne, Bas-Rhin, France (from Besson, 2005)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-8299207 elementor-widget elementor-widget-text-editor\" data-id=\"8299207\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">Gabion wall is also a reinforcement structure to stabilize slopes go to 2.1.2.2. more information on fall).<\/span><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-f034cce elementor-widget elementor-widget-image\" data-id=\"f034cce\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"539\" height=\"458\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/13_gabion-wall.jpg\" class=\"attachment-large size-large wp-image-3186\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/13_gabion-wall.jpg 539w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/13_gabion-wall-300x255.jpg 300w\" sizes=\"(max-width: 539px) 100vw, 539px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 13: gabion wall retaining structure (from TRB, 1978)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-27b8d6a elementor-widget elementor-widget-text-editor\" data-id=\"27b8d6a\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">For all these reinforcement systems, it is important to create a draining backfill with pervious material upstream the structure, in order to prevent water accumulation behind the wall and negative effects on the slope.<\/span><\/p><p>Another retaining structure developed in 1985 by French engineers of the \u201cLaboratoire Central des Ponts et Chauss\u00e9es\u201d is the \u201cArma Pneusol\u201d, a combination of tyres, backfill and grids layers, basically to stabilize highway slopes. The structure is planted to provide an aesthetic surface. With this reinforcement system, worn tyres are also recycled.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-f66e164 elementor-widget elementor-widget-image\" data-id=\"f66e164\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"593\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/14_armapneusol_besson-1024x593.jpg\" class=\"attachment-large size-large wp-image-3191\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/14_armapneusol_besson-1024x593.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/14_armapneusol_besson-300x174.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/14_armapneusol_besson-768x445.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/14_armapneusol_besson.jpg 1354w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 14: Schematic view of the \u201cArma Pneusol\u201d system (from Besson, 2005)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-ddb03c5 elementor-widget elementor-widget-image\" data-id=\"ddb03c5\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"293\" height=\"293\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/15_armapneusol_photo.jpg\" class=\"attachment-large size-large wp-image-3196\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/15_armapneusol_photo.jpg 293w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/15_armapneusol_photo-150x150.jpg 150w\" sizes=\"(max-width: 293px) 100vw, 293px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 15: Photograph of a \u201cArma Pneusol\u201d system (from http:\/\/www.aliapur.com)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-eddcf86 elementor-widget elementor-widget-text-editor\" data-id=\"eddcf86\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">Anchor walls are also be used. The principle is the same than employed for fall risk protection techniques (<\/span><a style=\"background-color: #ffffff; font-size: 1rem; text-align: left;\" href=\"http:\/\/www.besafenet.net\/en-gb\/natural-hazards-landslides#faq64\">go to 2.1.2.2. more information on fall<\/a><span style=\"font-size: 1rem; text-align: left;\">). Shotcrete or retaining wall can be used in combination with passive or active anchored cables (figure 16). This protection technique is rather an \u201cactive\u201d system, which increases the internal strength of the slope-forming material.<\/span><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-19eb765 elementor-widget elementor-widget-image\" data-id=\"19eb765\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"498\" height=\"383\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/16_anchor-system.jpg\" class=\"attachment-large size-large wp-image-3201\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/16_anchor-system.jpg 498w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/16_anchor-system-300x231.jpg 300w\" sizes=\"(max-width: 498px) 100vw, 498px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 16: Schematic view of roadway slope reinforcement (from Besson, 2005)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-c58a106 elementor-widget elementor-widget-text-editor\" data-id=\"c58a106\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">Finally, in most applications, a combination of the various methods outlined above is used. For example, soil-reinforcing grids can be mixed with any number of facing elements such as gabions, wire mesh or masonry blocks. Figures 17 and 18 show an example of rock-filled, gabion-faced embankment with Geogrid.<\/span><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-e269087 elementor-widget elementor-widget-image\" data-id=\"e269087\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"239\" height=\"225\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/17_geogrid-gabion-schema.jpg\" class=\"attachment-large size-large wp-image-3206\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 17: Schematic view of gabion-faced Geogrid embankment contructeds as part of a bank repair along Alhambra Creek, California. The use of soil backfill negated two-thirds of the required rockfill import necessary to fill a conventional all-gabion retention strucure (from Slosson and al., 1992)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-ce6bdf5 elementor-widget elementor-widget-image\" data-id=\"ce6bdf5\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"401\" height=\"277\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/18_geogrid-gabion.jpg\" class=\"attachment-large size-large wp-image-3211\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/18_geogrid-gabion.jpg 401w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/18_geogrid-gabion-300x207.jpg 300w\" sizes=\"(max-width: 401px) 100vw, 401px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 18: Photograph of the completed channel repair (from Slosson and al., 1992)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-1f25df0 elementor-widget elementor-widget-image\" data-id=\"1f25df0\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"787\" height=\"368\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/19_combination.jpg\" class=\"attachment-large size-large wp-image-3216\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/19_combination.jpg 787w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/19_combination-300x140.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/19_combination-768x359.jpg 768w\" sizes=\"(max-width: 787px) 100vw, 787px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 19: Example of combination of active and passive protection techniques to stabilize a slide (from Besson, 2005)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-27bbb0d elementor-widget elementor-widget-text-editor\" data-id=\"27bbb0d\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><strong style=\"font-size: 1rem; text-align: left;\">References<\/strong><\/p><p>BESSON L., 2005. Les risques naturels: de la connaissance pratique \u00e0 la gestion administrative. Editions Techni. Cit\u00e9s, Voiron, 60 p.<br \/>FLAGEOLLET J.C., 1988. Les mouvements de terrain et leur pr\u00e9vention, Masson, Paris, 224 p.<br \/>GUEFFON M., 2005. Les travaux de pr\u00e9vention actifs contre les glissements de terrain : stabilisation et drainage des zones instables. Risques Infos n\u00b016, p. 13-16<br \/>SLOSSON E., KEENE A.G., JOHNSON J.A., 1992. Landslides\/Landslide mitigation. In: Reviews of Engineering Geology, Volume IX, Colorado<br \/>TRANSPORTATION RESEARCH BOARD, 1978. Landslides: Analysis and Control. National Academy of Sciences, Special Report 176, Washington DC<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p>\n<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-2032\" class=\"elementor-tab-title\" data-tab=\"2\" role=\"tab\" aria-controls=\"elementor-tab-content-2032\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">10.2. More information on how damages due to sinking and shrinking-swelling can be repaired or even be prevented<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-2032\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"2\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-2032\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"3223\" class=\"elementor elementor-3223\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-64daebe elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"64daebe\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-f1fa883\" data-id=\"f1fa883\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-3e784e6 elementor-widget elementor-widget-text-editor\" data-id=\"3e784e6\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Prevention and repairing of the damages due sinking process are in line with the techniques used to protect against the shrinking-swelling process.<\/p><p>Techniques of pre-consolidation of the soil by drainage and application of overload before the construction process are commonly applied.<\/p><p>Two types of repairing methods and prevention techniques are generally undertaken according to their efficiency and costs:<\/p><ul><li>\u201chard\u201d methods (high expensive costs but generally efficient), consisting of the reinforcement of the building with piles and steeled girder, alternate piles, micro-stakes, chaining, etc;<\/li><li>\u201clight\u201d methods (less expensive costs and often sufficient), consisting of positive actions in the surrounding of the building (control of the water discharge, control of the vegetation with root screens and the choice of adapted vegetation variety, isothermal protection of the foundations, artificial increase in soil humidity with micro-porous pumps etc&#8230;).<\/li><\/ul><p><strong>References:<\/strong><br \/>Bekkouche N. et al., 1990. Foundation problems in Champlain clays during droughts: I \u2013 rainfall deficits in Montreal (1930-1988). Revue Canadienne de G\u00e9otechnique, vol. 27, n\u00b03, pp. 285-293.<br \/>Bekkouche N. et al., 1992. Foundation problems in Champlain clays during droughts: II \u2013 Cases histories. Revue Canadienne de G\u00e9otechnique, vol. 29, n\u00b02, pp. 169-187.<br \/>Biddle P.J. 1983. Pattern of soil drying and moisture deficit in the vicinity of trees on city soils. G\u00e9otechnique, vol. 33, n\u00b02, pp.107-126.<br \/>Driscoll R. 1983. The influence of vegetation on the swelling and shrinking of clay soils in Britain. G\u00e9otechnique, vol. 33, n\u00b02, pp.93-105.<br \/>Embleton, C., and Embleton C. (eds.) (1997), Geomorphological Hazards of Europe. Developments in Earth Surface Processes 5. Amsterdam : Elsevier, 524p.<br \/>Flageollet, J. C. (1988), Les mouvements de terrain et leur pr\u00e9vention, Paris : Masson, 224p.<br \/>Maquaire, O., 2005. Geomorphic hazards and natural risks, In: Koster, E., A. (ed.), The Physical Geography of Western Europe, Oxford Regional Environments, Oxford University Press, Chapter 18, 354-377.<\/p><p><strong>Internet links:<\/strong><br \/><a href=\"http:\/\/www.prim.net\/professionnel\/documentation\/dossiers_info\/nat\/low\/mouvtTerr.pdf\" target=\"_blank\" rel=\"noopener\">http:\/\/www.prim.net\/professionnel\/documentation\/dossiers_info\/nat\/low\/mouvtTerr.pdf<\/a><br \/><a href=\"http:\/\/www.argiles.fr\/\" target=\"_blank\" rel=\"noopener\">http:\/\/www.argiles.fr\/<\/a><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p>\n<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-20811\" class=\"elementor-tab-title\" data-tab=\"11\" role=\"tab\" aria-controls=\"elementor-tab-content-20811\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">11. Comment r\u00e9agir face \u00e0 un glissement de terrain ?<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-20811\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"11\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-20811\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"7939\" class=\"elementor elementor-7939 elementor-3227\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-eab039c elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"eab039c\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-a1b9219\" data-id=\"a1b9219\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-ecf3659 elementor-widget elementor-widget-text-editor\" data-id=\"ecf3659\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>Plusieurs cas de figure se pr\u00e9sentent en cas de glissement de terrain\u00a0: vous pouvez vous trouver dessus, sur sa course, ou encore arriver en voiture sur un lieu touch\u00e9 par un tel mouvement de terrain.<\/p>\n<p>Dans la plupart des cas, surtout si une pente gigantesque glisse dans votre direction, peu de choix s\u2019offrent \u00e0 vous. Cela \u00e9tant dit, certains conseils d\u2019ordre g\u00e9n\u00e9ral peuvent toujours s\u2019av\u00e9rer utiles dans ce genre de situation\u00a0\u2013\u00a0ou pour faire face \u00e0 tout autre type de catastrophe naturelle.<\/p>\n<p>Certaines \u00e9coles sont r\u00e9ellement expos\u00e9es au risque de glissement de terrain. Il peut \u00eatre judicieux d\u2019y organiser des exercices de simulation, pour habituer les \u00e9l\u00e8ves et le personnel \u00e0 adopter les bons r\u00e9flexes, comme ceux indiqu\u00e9s ci-dessous.<\/p>\n<ul>\n<li>Avant l\u2019\u00e9v\u00e9nement<\/li>\n<\/ul>\n<p>Essayez de savoir si des glissements de terrain se sont d\u00e9j\u00e0 produits dans la zone en contactant les services publics et informez-vous aupr\u00e8s de la protection civile pour savoir comment r\u00e9agir en cas d\u2019urgence, conna\u00eetre les plans d\u2019\u00e9vacuation et \u00e9laborer votre propre plan d\u2019urgence.<\/p>\n<ul>\n<li>Au cours de l\u2019\u00e9v\u00e9nement<\/li>\n<\/ul>\n<ol>\n<li>Vous vous trouvez \u00e0 l\u2019int\u00e9rieur d\u2019un b\u00e2timent (dans une salle de classe par exemple)\u00a0:<\/li>\n<\/ol>\n<p>a) ne vous pr\u00e9cipitez pas dehors, restez o\u00f9 vous \u00eates\u00a0;<\/p>\n<p>b) r\u00e9fugiez-vous sous une table, une architrave ou pr\u00e8s des murs porteurs\u00a0;<\/p>\n<p>c) n\u2019utilisez pas les ascenseurs\u00a0;<\/p>\n<p>d) \u00e9loignez-vous des fen\u00eatres, des portes vitr\u00e9es et des placards.<\/p>\n<ol>\n<li value=\"2\">Vous vous trouvez \u00e0 l\u2019ext\u00e9rieur\u00a0:<\/li>\n<\/ol>\n<p>a) \u00e9loignez-vous des b\u00e2timents, des arbres, de l\u2019\u00e9clairage public, des c\u00e2bles \u00e9lectriques et des lignes t\u00e9l\u00e9phoniques;<\/p>\n<p>b) \u00e9vitez (\u00e0 pied ou en voiture) les routes r\u00e9cemment frapp\u00e9es par un glissement de terrain\u00a0;<\/p>\n<p>c) ne vous aventurez par sur un terrain en cours de glissement ;<\/p>\n<p>d) ne p\u00e9n\u00e9trez pas \u00e0 l\u2019int\u00e9rieur d\u2019une maison b\u00e2tie sur un terrain d\u00e9stabilis\u00e9 avant son expertise compl\u00e8te par les services comp\u00e9tents.<\/p>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-77b5d19 elementor-widget elementor-widget-image\" data-id=\"77b5d19\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"768\" height=\"752\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Whattodobooklet-768x752.jpg\" class=\"attachment-medium_large size-medium_large wp-image-3232\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Whattodobooklet-768x752.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Whattodobooklet-300x294.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Whattodobooklet-1024x1002.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Whattodobooklet-1536x1503.jpg 1536w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Whattodobooklet-2048x2004.jpg 2048w\" sizes=\"(max-width: 768px) 100vw, 768px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-0a9c712 elementor-widget elementor-widget-text-editor\" data-id=\"0a9c712\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<div class=\"tdFaqCond row\">\n<p style=\"text-align: center;\"><em>\u201cCivil protection in family\u201d: a booklet edited by the Italian Civil Protection containing the instruction about \u201cwhat to do\u201d in case of disasters.<\/em><\/p>\n<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-27b7c7d elementor-widget elementor-widget-accordion\" data-id=\"27b7c7d\" data-element_type=\"widget\" data-widget_type=\"accordion.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<div class=\"elementor-accordion\" role=\"tablist\">\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-4161\" class=\"elementor-tab-title\" data-tab=\"1\" role=\"tab\" aria-controls=\"elementor-tab-content-4161\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">11.1 More information on what to do in the case of a landslide<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-4161\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"1\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-4161\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"3238\" class=\"elementor elementor-3238\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-c547924 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"c547924\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-047b564\" data-id=\"047b564\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-85548d1 elementor-widget elementor-widget-text-editor\" data-id=\"85548d1\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<ul>\n \t<li><strong>Prior to the event<\/strong><\/li>\n<\/ul>\nBecome familiar with the land around you. Try to learn whether landslides have occurred in your area by contacting Public Administration Offices and\/or Earth Sciences Departments of the nearest University.\nContact your local Civil Protection to learn about the emergency response and evacuations plans for your area and prepare your own emergency plans.\n<ul>\n \t<li><strong>During the event<\/strong><\/li>\n<\/ul>\n<em><strong>&#8211; If you are inside a building\u00a0<\/strong>(for example in the classroom)<\/em>\n<table class=\"table table-striped table-align-middle table-with-image\">\n<tbody>\n<tr>\n<td><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-medium wp-image-3257\" style=\"font-family: inherit; font-size: inherit;\" src=\"http:\/\/besafenet.dgmedialink.com\/wp-content\/uploads\/2020\/11\/1_stay-there.jpg\" alt=\"\" width=\"289\" height=\"257\" \/><\/td>\n<td><strong>Don\u2019t rush outside, stay where you are<\/strong>. By staying inside the building you are more protected than outside.<\/td>\n<\/tr>\n<tr>\n<td><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-medium wp-image-3252\" src=\"http:\/\/besafenet.dgmedialink.com\/wp-content\/uploads\/2020\/11\/2_close-the-wall.jpg\" alt=\"\" width=\"285\" height=\"256\" \/><\/td>\n<td><strong>Take shelter under a table, below the architrave, or near the bearing walls.<\/strong>\u00a0They protect you from possible cave &#8211; ins.<\/td>\n<\/tr>\n<tr>\n<td><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-medium wp-image-3247\" src=\"http:\/\/besafenet.dgmedialink.com\/wp-content\/uploads\/2020\/11\/3_away-from-glass.jpg\" alt=\"\" width=\"286\" height=\"257\" \/><\/td>\n<td><strong>Stay\u00a0 away from windows,\u00a0 doors with glass and cupboards<\/strong>. They could fall and hurt you.<\/td>\n<\/tr>\n<tr>\n<td><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-3242\" src=\"http:\/\/besafenet.dgmedialink.com\/wp-content\/uploads\/2020\/11\/4_not-use-lift.jpg\" alt=\"\" width=\"286\" height=\"255\" \/><\/td>\n<td><strong>Don\u2019t use lifts.\u00a0<\/strong>They could get stuck and prevent you from exiting.\n<strong>Help the other people around you. <\/strong>Maybe there are some people hurt or even disabled or people that are in trouble to move by themselves. Remember to help them to go out of the building when it will be safe the exit.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n&#8211;\u00a0<em><strong>If you are outdoors<\/strong><\/em>\n<table class=\"table table-striped table-align-middle table-with-image\">\n<tbody>\n<tr>\n<td><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-medium wp-image-3278\" src=\"http:\/\/besafenet.dgmedialink.com\/wp-content\/uploads\/2020\/11\/5_away-from-building.jpg\" alt=\"\" width=\"286\" height=\"258\" \/><\/td>\n<td><strong>Move away from buildings, trees, streetlights, electric cables and telephone lines.<\/strong>\u00a0They could fall down and\u00a0 hurt you.<\/td>\n<\/tr>\n<tr>\n<td><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-medium wp-image-3273\" src=\"http:\/\/besafenet.dgmedialink.com\/wp-content\/uploads\/2020\/11\/6_not-drive.jpg\" alt=\"\" width=\"285\" height=\"256\" \/><\/td>\n<td><strong>Don\u2019t walk or drive along a road where a landslide has recently occured.<\/strong>\u00a0It is instable material that could start moving again.<\/td>\n<\/tr>\n<tr>\n<td><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-medium wp-image-3268\" src=\"http:\/\/besafenet.dgmedialink.com\/wp-content\/uploads\/2020\/11\/7_not-walk-over.jpg\" alt=\"\" width=\"285\" height=\"257\" \/><\/td>\n<td><strong>Don\u2019t venture out\u00a0 on a landslide body.\u00a0<\/strong>The material of a landslide, even if stable in appearance, can hide dangerous underlying holes.<\/td>\n<\/tr>\n<tr>\n<td><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-3263\" src=\"http:\/\/besafenet.dgmedialink.com\/wp-content\/uploads\/2020\/11\/8_not-entry.jpg\" alt=\"\" width=\"287\" height=\"256\" \/><\/td>\n<td><strong>Do not enter inside houses involved in a landslides before a thorough assessment by experts.\u00a0<\/strong>They could have sustained structural damage and be unsafe.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<strong>References<\/strong>: drawings taken from \u201cProtezione Civile in Famiglia\u201d, Dipartimento di Protezione Civile (2005), Italy (Download at: www.protezionecivile.it):\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-d7963ae elementor-widget elementor-widget-image\" data-id=\"d7963ae\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"1002\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Whattodobooklet-1024x1002.jpg\" class=\"attachment-large size-large wp-image-3232\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Whattodobooklet-1024x1002.jpg 1024w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Whattodobooklet-300x294.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Whattodobooklet-768x752.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Whattodobooklet-1536x1503.jpg 1536w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/Whattodobooklet-2048x2004.jpg 2048w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p>\n<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-20812\" class=\"elementor-tab-title\" data-tab=\"12\" role=\"tab\" aria-controls=\"elementor-tab-content-20812\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">12. Quels types de cartes existe-t-il pour les glissements de terrain ?<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-20812\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"12\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-20812\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"7941\" class=\"elementor elementor-7941 elementor-3288\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-7ba187c elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"7ba187c\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-d37ddb1\" data-id=\"d37ddb1\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-6b72f9b elementor-widget elementor-widget-text-editor\" data-id=\"6b72f9b\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>L\u2019\u00e9tude des risques de glissement de terrain passe souvent par l\u2019\u00e9tablissement de cartes. Il peut s\u2019agir soit de documents simples (cartes g\u00e9omorphologiques et cartes des glissements de terrain), soit de cartes de susceptibilit\u00e9 aux mouvements de terrain et de zonage des risques.<\/p>\n<ul>\n<li>\u00c0 quoi servent ces cartes\u00a0?<\/li>\n<\/ul>\n<p>La cartographie est\u00a0:<\/p>\n<ul>\n<li><strong>directe<\/strong>, lorsque l\u2019\u00e9tendue et la r\u00e9partition des glissements de terrain peuvent \u00eatre caract\u00e9ris\u00e9es d\u2019un point de vue g\u00e9omorphologique\u00a0pour d\u00e9duire par extrapolation la stabilit\u00e9 des autres pentes de la zone \u00e9tudi\u00e9e\u00a0;<\/li>\n<li><strong>indirecte<\/strong>, lorsque le risque de glissement de terrain est \u00e9valu\u00e9 en tenant compte ou non de la r\u00e9partition des glissements de terrain.<\/li>\n<\/ul>\n<p>Une cartographie directe est g\u00e9n\u00e9ralement r\u00e9alis\u00e9e au moyen d\u2019une photo-interpr\u00e9tation d\u2019images a\u00e9riennes, de relev\u00e9s de terrain et d\u2019un travail de recherche bibliographique (litt\u00e9rature r\u00e9cente et archives).<\/p>\n<p>La cartographie indirecte des glissements de terrain se fonde sur les facteurs (g\u00e9omorphologiques et g\u00e9ologiques, principalement) potentiellement favorables au d\u00e9clenchement de tels ph\u00e9nom\u00e8nes. Il en r\u00e9sulte donc des cartes de susceptibilit\u00e9 des zones au risque de glissement de terrain.<\/p>\n<p>Les<em>\u00a0inventaires cartographiques des glissements de terrain<\/em>\u00a0sont faciles \u00e0 comprendre \u00e0 la fois par les experts (g\u00e9ologues et g\u00e9omorphologues par exemple) et les non-initi\u00e9s (d\u00e9cideurs, urbanistes et responsables de la protection civile).<\/p>\n<ul>\n<li>O\u00f9 peut-on se procurer ces cartes\u00a0?<\/li>\n<\/ul>\n<p>Les cartes sont g\u00e9n\u00e9ralement disponibles aupr\u00e8s des services publics et des laboratoires de recherche. On en trouve \u00e9galement dans les revues et les ouvrages sp\u00e9cialis\u00e9s.<\/p>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-c539215 elementor-widget elementor-widget-image\" data-id=\"c539215\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1021\" height=\"655\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/CartDissestRERmapex1.png\" class=\"attachment-large size-large wp-image-3293\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/CartDissestRERmapex1.png 1021w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/CartDissestRERmapex1-300x192.png 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/CartDissestRERmapex1-768x493.png 768w\" sizes=\"(max-width: 1021px) 100vw, 1021px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Landslides typology: a1d) active earthflow; a2b) dormant slide; a2d) dormant earthflow; a2g) dormant complex landslide  Map of the hydrogeological disturbance of the Regione Emilia Romagna (https:\/\/applicazioni.regione.emilia-romagna.it\/cartografia_sgss\/user\/viewer.jsp?service=dissesto, scale 1:5000)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-fc36259 elementor-widget elementor-widget-accordion\" data-id=\"fc36259\" data-element_type=\"widget\" data-widget_type=\"accordion.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<div class=\"elementor-accordion\" role=\"tablist\">\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<div id=\"elementor-tab-title-2641\" class=\"elementor-tab-title\" data-tab=\"1\" role=\"tab\" aria-controls=\"elementor-tab-content-2641\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><i class=\"fas fa-plus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><i class=\"fas fa-minus\"><\/i><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" href=\"\">12.1 More information on the mapping of landslides<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<div id=\"elementor-tab-content-2641\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"1\" role=\"tabpanel\" aria-labelledby=\"elementor-tab-title-2641\"><p>\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"3298\" class=\"elementor elementor-3298\">\n\t\t\t\t\t\t<div class=\"elementor-inner\">\n\t\t\t\t<div class=\"elementor-section-wrap\">\n\t\t\t\t\t\t\t\t\t<section class=\"has_eae_slider elementor-section elementor-top-section elementor-element elementor-element-f73f800 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"f73f800\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t\t\t<div class=\"elementor-row\">\n\t\t\t\t\t<div class=\"has_eae_slider elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-4185823\" data-id=\"4185823\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-column-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-e915312 elementor-widget elementor-widget-text-editor\" data-id=\"e915312\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p>By Alessandro Pasuto1, Mauro Soldati2, &amp; Doriano Castaldini2<br \/>1 CNR \u2013 IRPI, Padova (Italy)<br \/>2 Dipartimento di Scienze della Terra, Universit\u00e0 di Modena e Reggio Emilia (Italy)<\/p><p>Mapping is often a necessary step in landslide hazard studies. Maps may consist either of basic documents such as geomorphological maps and landslide maps or of landslide susceptibility maps and hazard zonation maps. Mapping can be defined as direct, when the landslide extent and distribution are recognised on a geomorphological basis with the aim of extrapolating slope stability assessments to the rest of the investigated area, or indirect, when the possibility of landslide occurrence is assessed in relation to the controlling factors, with or without consideration of landslide distribution (Hansen, 1984).<\/p><p>Direct mapping is usually obtained through aerial photo-interpretation and ground surveys, which vary proportionally according to the scale adopted for the study, together with bibliographical and archive investigations. The result can be inventory maps which record landslide distribution over an area (e.g Ryb\u00e1r, 1973; Alger &amp; Brabb, 1985; Guzzetti &amp; Cardinali, 1989). Landslides inventory maps are effectively and easily understandable products fot both experts, such as geologists and geomorphologists, and for not experts, including decision makers, planners and civil defence managers (Galli et al., 2008).<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-727995d elementor-widget elementor-widget-image\" data-id=\"727995d\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"554\" height=\"661\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/1_CartaCamporagh.jpg\" class=\"attachment-large size-large wp-image-3301\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/1_CartaCamporagh.jpg 554w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/1_CartaCamporagh-251x300.jpg 251w\" sizes=\"(max-width: 554px) 100vw, 554px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 1 The Camporaghena landslide map, a large multiple rotational slide located in the Tuscan side of the Northern Apennines. The Red and Orange colours indicate, respectively active and dormant sectors (From Nardi et al., 1990).<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-9425055 elementor-widget elementor-widget-image\" data-id=\"9425055\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"778\" height=\"531\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_CamporagFoto.jpg\" class=\"attachment-large size-large wp-image-3306\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_CamporagFoto.jpg 778w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_CamporagFoto-300x205.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/2_CamporagFoto-768x524.jpg 768w\" sizes=\"(max-width: 778px) 100vw, 778px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig.2 The Camporaghena landslide, which was pre-existing, was reactivated by the 1920 Garfagnana-Lunigiana strong earthquake and contributed to the damage caused by this seismic shock in the village. Wide portions of the landslide are still active and frequently involve the main road and several houses. (From Nardi et al., 1990).<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-7c2056d elementor-widget elementor-widget-text-editor\" data-id=\"7c2056d\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">The Landslides inventory maps are generally the basis for further detailed studies aiming to assess future failures. The information contained in these maps may also include landslide type, bedrock lithology, superficial deposits, slope angles, engineering geological zonation etc.<\/span><\/p><p>In Italy an homogenous and updated Inventory of Italian landslides has been implemented by APAT (Geological Survey of Italy\/Land Protection and Georesources Department). The Italian Inventory of landslides (IFFI) holds over 460,000 phenomena occurred in the Italian territory.<br \/>APAT published the IFFI Inventory on the Internet as well as the report on the Project (APAT 2007) with the aim of disseminating information about landslides to national and local administrations, research institutes, geologists, engineers and citizens .<br \/>Go to IFFI Inventory web site (<a href=\"http:\/\/www.apat.gov.it\/site\/it-IT\/Progetti\/IFFI_-_Inventario_dei_fenomeni_franosi_in_Italia\/\">http:\/\/www.apat.gov.it\/site\/it-IT\/Progetti\/IFFI_-_Inventario_dei_fenomeni_franosi_in_Italia\/<\/a>)<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-eeb0294 elementor-widget elementor-widget-image\" data-id=\"eeb0294\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"805\" height=\"1024\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/3_IFFImap-805x1024.jpg\" class=\"attachment-large size-large wp-image-3311\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/3_IFFImap-805x1024.jpg 805w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/3_IFFImap-236x300.jpg 236w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/3_IFFImap-768x977.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/3_IFFImap.jpg 928w\" sizes=\"(max-width: 805px) 100vw, 805px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 3. Landslide index (%) in Italy (by IFFI Inventory web site)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-37534d3 elementor-widget elementor-widget-text-editor\" data-id=\"37534d3\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">In the Emilia &#8211; Romagna Region, the Instability Inventory Maps, created on the base of traditional geological maps, have a great applied significance for territorial planning. In fact, it is forbidden to built up on \u00ab\u00a0areas affected by active landslides\u00a0\u00bb (landslides which are currently active or that have been reactivated since the last 30 years) meanwhile it is allowed to build up on \u00a0\u00bb areas affected by dormant landslides\u00a0\u00bb (landslides that have not showed signs of activity since the last 30 years and that could be reactivated by their original causes) or on \u00ab\u00a0Potentially instable areas\u201d (quaternary deposits affected by evident superficial morphogenetic processes) only if prevenction and mitigation measures have been adopted.<\/span><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-431216f elementor-widget elementor-widget-image\" data-id=\"431216f\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"982\" height=\"782\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/4_CasonaSDissesto.jpg\" class=\"attachment-large size-large wp-image-3316\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/4_CasonaSDissesto.jpg 982w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/4_CasonaSDissesto-300x239.jpg 300w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/4_CasonaSDissesto-768x612.jpg 768w\" sizes=\"(max-width: 982px) 100vw, 982px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig.4 .Extract of the Instability Inventory Maps at the scale 1:5,000. Casona Sud area in the Modena Apennines. In red \u00ab\u00a0Areas affected by active landslides\u00a0\u00bb; in yellow \u00a0\u00bb Areas affected by dormant landslides\u00a0\u00bb , in violet the study area (from Provincia di Modena, 2006, see also http:\/\/www.provincia.modena.it\/page.asp?IDCategoria=7&amp;IDSezione=863 http:\/\/archiviocartografico.regione.emilia-romagna.it\/)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-5f27d87 elementor-widget elementor-widget-image\" data-id=\"5f27d87\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"615\" height=\"394\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/5_CasonaS.jpg\" class=\"attachment-large size-large wp-image-3321\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/5_CasonaS.jpg 615w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/5_CasonaS-300x192.jpg 300w\" sizes=\"(max-width: 615px) 100vw, 615px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 5. Panoramic vieuw from East to West of the Casona Sud area in the Modena Apennines (Photo D. Castaldini)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-5afcd75 elementor-widget elementor-widget-text-editor\" data-id=\"5afcd75\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">Geomorphological maps are another product of direct mapping. These are generally at a larger scale (less than 1:25,000) than those described above and form a very useful basis for landslide hazard studies since they include details on general slope morphology and related processes, and define the type of failure and degree of activity as well as the features associated with landslides. Geomorphological mapping may be easily and usefully applied to the study of mass movements.<\/span><\/p><p>There exist many significant examples of landslide-orientated geomorphological maps, such as that of Brundsen et al. (1975), carried out with aim of identifying landslide hazard in an area of Nepal where the construction of a road and a bridge was proposed, or that of Panizza (1990) where the landslides surrounding the town of Cortina d&rsquo;Ampezzo (Italian Dolomites) are mapped in detail. An interesting attempt to include the temporal aspect in landslide mapping was made by Flageollet (1994) in the above mentioned Dolomite area. The temporal information reported on the computer-based landslide map of the area of Cortina d&rsquo;Ampezzo is related to periods of activity during the Holocene and to the frequency and incidence (first time failure or removement failure) of the movements. An updating of the Panizza (1990) map has been carried out by Pasuto et al. (2005).<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-19bda92 elementor-widget elementor-widget-image\" data-id=\"19bda92\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"971\" height=\"1024\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/6a_CORTINApp-971x1024.jpg\" class=\"attachment-large size-large wp-image-3326\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/6a_CORTINApp-971x1024.jpg 971w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/6a_CORTINApp-285x300.jpg 285w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/6a_CORTINApp-768x810.jpg 768w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/6a_CORTINApp.jpg 1068w\" sizes=\"(max-width: 971px) 100vw, 971px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-4484b1b elementor-widget elementor-widget-image\" data-id=\"4484b1b\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"776\" height=\"928\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/6b_1egendafrane.jpg\" class=\"attachment-large size-large wp-image-3331\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/6b_1egendafrane.jpg 776w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/6b_1egendafrane-251x300.jpg 251w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/6b_1egendafrane-768x918.jpg 768w\" sizes=\"(max-width: 776px) 100vw, 776px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig.6. Extract of the Geomorphological map of the Cortina d\u2019Ampezzo area (Dolomites, Italian Alps) at the 1:20,000 scale (from Pasuto et al., 2005).<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-1f17b20 elementor-widget elementor-widget-image\" data-id=\"1f17b20\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"900\" height=\"581\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/7_CortinaSoldati2.jpg\" class=\"attachment-large size-large wp-image-3336\" alt=\"\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig.7. Panoramica view of the Cortina d\u2019Ampezzo area of Fig. 5 (Dolomites, Italian Alps)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-f9362ae elementor-widget elementor-widget-text-editor\" data-id=\"f9362ae\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">Geomorphological maps may in many cases be too complicated to be read by non-specialists. This is the reason why planners and engineers are generally provided with derivative maps which appear simpler from a purely graphic standpoint and take into account only those processes and landforms that are connected with slope instability. The product can be a geomorphologically-based landslide hazard map. Many examples, carried out according to different methodologies, are known in literature. The first example should refer to the French ZERMOS (Zones Expos\u00e9es aux Risques de Mouvement du Sol et du Sous-sol) hazard maps which have been produced for several sample areas at a scale 1:25,000. The hazard (actual and potential) is assessed and rated taking into account distribution of landslides, evidence of instability, as well as geological, geomorphological and hydrological aspects.<\/span><\/p><p>Another significant example is provided by Kienholz (1978) who carried out a study in the Grindenwald, an area of the Swiss Alps affected by mass movements and avalanches; first a geomorphological map was produced and from this a natural hazard map was obtained. The degree of hazard was assessed for a high number of previously defined geomorphological units using checklists.<\/p><p>When the casual factors of landslides can be recognised, measured and mapped and the analysis of the distributions of the different factors controlling landsliding can be made, indirect mapping can be carried out.<\/p><p>An original method aiming at the elaboration of hazard susceptibility maps has been defined and tested in a few sites in Italy and has been adopted by the National Geological Survey as the official procedure for the compilation of geological hazard maps (Amanti et al., 1992). This method includes both indirect and direct mapping procedures. In fact, this approach consists, on the one hand, of the analysis of the causes of instability (ascribable to both slope and fluvial processes) which are outlined in a series of thematic maps (geological, hydrogeological, vegetational etc.) and weighted by means of specific procedures, with the aim of producing a first derivative map (integrated analysis map) depicting the distribution of potentially unstable areas. On the other hand, by means of geomorphological investigations, the analysis of the effects of instability is carried out in order to give an outline of landforms and processes, both active and inactive, referable to geomorphological instability. The cartographic documents produced during this phase are a geomorphological map and a second derivative map (map of geomorphological dynamics) showing the areas which are at present unstable. The comparison and critical discussion of these two derivative maps lead to the production of a \u00ab\u00a0geomorphological hazard map\u00a0\u00bb, a concise document depicting present and potential unstable areas subdivided according to the causes of instability.<br \/>A partly similar approach was used for research on landslide hazard in Tuscany (Italy) which led to the elaboration of several landslide maps, accompanied by geological information permitting the assessment, albeit qualitatively, of the ratio between the degree of stability attributed to an area and its structural characteristics. In these hazard maps the following categories are distinguished: highly hazardous areas, including active and dormant landslides, areas characterised by high potential instability linked to the morphological aspects, areas prone to landsliding owing to lithological aspects, areas of medium stability and finally stable areas (Nardi et al., 1985).<\/p><p>Jones (1992) refers to a further approach, Land Systems Mapping, which is placed among indirect mapping techniques and is based on the subdivision of the study territory into limited areas (land systems, land units, land elements, passing from large scale to small scale subdivisions) in which predictable combinations of landforms, soils, vegetation and superficial processes take place. This approach, created with the goal of producing basic maps for rural planning, has been extremely useful in landslide hazard assessment since it allows large portions of territory to be quickly classified providing a useful regional picture for data collection and storage.<br \/>In the last decade many other methods has been proposed for the assessment of landslide hazard and risk all over the world (e.g. Heinmann et al.. 1998, Raetzo et al., 2002; Santacana et al., 2003; Zezer\u00e8 et al. 2004; Guzzetti et al.. 2005) because the quantification of risk has gained importance in many disciplines. Anyhow the problem of attempting to quantify landslide hazard and risk is still difficult to solve (Cascini et al. 2005, van Westen et al., 2005).<\/p><p>In Italy, the zoning of areas subject to hydro-geological risks has been regulated since 1998 by a specific law and its associated application decree, which were released after the \u201cSarno\u201d mudflow disaster (go to 13.2. Sarno study case). However, these juridical documents contain only some general guidelines for a common working methodology to be adopted for hydro-geological risk assessment in all of the Italian territory, and leave Basin Authorities free to define their own specific guidelines and, upon will, involve in this process research institutions and private consultants. This led to a large differentiation of procedures among Basin Authorities, and in practice the only standards adopted nation wide regard the work steps to be adopted, the goal of the investigation (that is the subdivision of risk in 4 classes) and the constrains to be adopted on high risk zones in terms of land use limitation and land management policy.<\/p><p>In particular, the risk zoning was calibrated according to the 4 risk classes defined by the Central Goverment as follows:<br \/>i) Very high (R4): human life loss and destruction of buildings, infrastructure and environmentall as well as interruption of economic activities are expected;<br \/>ii) High (R3): victims, functional damage to buildings and infrastructure, as well as partial interruption of economic activities are possible;<br \/>iii) Medium (R2): limited damage to buildings, infrastructure and environmentalmay occur;<br \/>iv) Low (R1): social, economic and environmental damageare of marginal relevance;<\/p><p>The results obtained for the territory of the National Authority of Liri &#8211; Garigliano and Volturno river basin (a territory of about 12,000 km2 located in Central-Southern Italy) are summarized in the following (Cascini, 2005). Inside the study area, undeveloped areas affected by dormant, active or potential landslides were mapped and classified according to the risk classes defined and the Cruden and Varnes (1996) suggestions; these areas were considered worthy of different attention levels.<\/p><p>To zone the risk and attention areas, geological, geomorphological and soil cover maps were preliminarily compiled. Subsequently, using these maps as well as aerphoto interpretation and available informations, 30,000 landslides together with their surroinding areas, and zones potentially affected by fast slope movements were mapped using Varnes (1978) classification, creep evidence, state of activity and other criteria described by Cascini (2005)(Fig.8).<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-9566b3e elementor-widget elementor-widget-image\" data-id=\"9566b3e\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"428\" height=\"468\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/8_CasiniLandsMap.png\" class=\"attachment-large size-large wp-image-3341\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/8_CasiniLandsMap.png 428w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/8_CasiniLandsMap-274x300.png 274w\" sizes=\"(max-width: 428px) 100vw, 428px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 8. Example of landslide inventory map (from Cascini, 2005)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-01d352f elementor-widget elementor-widget-text-editor\" data-id=\"01d352f\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">Starting from these data, danger maps were then implemented by adopting velocity estimates as well as of the source and propagation areas potentially affected by first stage movements (Fig.9).<\/span><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-528d31a elementor-widget elementor-widget-image\" data-id=\"528d31a\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"437\" height=\"451\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/9_CascinidangerMap.png\" class=\"attachment-large size-large wp-image-3346\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/9_CascinidangerMap.png 437w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/9_CascinidangerMap-291x300.png 291w\" sizes=\"(max-width: 437px) 100vw, 437px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 9. Example of landslide danger map (from Cascini, 2005)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-5fa80e8 elementor-widget elementor-widget-text-editor\" data-id=\"5fa80e8\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><span style=\"font-size: 1rem; text-align: left;\">Simplified hazard maps as well as simplified vulnerability maps for all the towns (450) were produced. Referring to the Varnes&rsquo; formula, the risk classes (Fig. 10) were obtained by overlapping hazard and vulnerability maps. An example of map containing the attention and risk classes previously defined is shown in Fig. 11.<\/span><\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-b30440f elementor-widget elementor-widget-image\" data-id=\"b30440f\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"463\" height=\"260\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/10_CasciniRiskScale.png\" class=\"attachment-large size-large wp-image-3351\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/10_CasciniRiskScale.png 463w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/10_CasciniRiskScale-300x168.png 300w\" sizes=\"(max-width: 463px) 100vw, 463px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 10. Nominal scale for risk level evaluation (from Cascini, 2005)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-c51233c elementor-widget elementor-widget-image\" data-id=\"c51233c\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-image\">\n\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"430\" height=\"433\" src=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/11_CasciniRiskMap.png\" class=\"attachment-large size-large wp-image-3356\" alt=\"\" srcset=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/11_CasciniRiskMap.png 430w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/11_CasciniRiskMap-298x300.png 298w, https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/11_CasciniRiskMap-150x150.png 150w\" sizes=\"(max-width: 430px) 100vw, 430px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Fig. 11. Example of map containing attention and risk zones (from Cascini, 2005)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-0136a08 elementor-widget elementor-widget-text-editor\" data-id=\"0136a08\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-text-editor elementor-clearfix\">\n\t\t\t\t<p><strong style=\"font-size: 1rem; text-align: left;\">References<\/strong><\/p><p>Alger, C.S. and Brabb, E.E., 1985. Bibliography of United States landslide maps and reports. US Geological Survey Open-File Report, 85-585, 119 pp.<br \/>Amanti, M., Carrara, A., Castaldo, G., Colosimo, P., Gisotti, G., Govi, M., Marchionna, G., Nardi, R., Panizza, M., Pecci, M. and Vianello, G., 1992. Linee guida per la realizzazione di una cartografia della pericolosit\u00e0 geologica connessa ai fenomeni di instabilit\u00e0 dei versanti alla scala 1:50.000 (versione preliminare). Servizio Geologico Nazionale, Roma, 53 pp.<br \/>APAT (2007) &#8211; Rapporto sulle frane in Italia. Il Progetto IFFI &#8211; Metodologia, risultati e rapporti regionali. Rapporti 78\/2007, 680 pp.<br \/>Brunsden, D., Doornkamp, J.C., Fookes, P.G., Jones, D.K.C. and Kelly, J.M.H., 1975. Large scale geomorphological mapping and highway engineering design. Quart. J. Engng. Geol., 8: 227-253.<br \/>Cascini L,, 2005. Risk assessment of fast landslides &#8211; From theory to practice. General Report. Proc. of the Int. on \u00ab\u00a0Fast Slope Movements &#8211; Prediction and Prevention for Risk Mitigation\u00a0\u00bb, Napoli, Vol. 2. Patron Editore.<br \/>Cascini L,. Bonnard C., Corominas J., Jibson R. and Montero-Olarte J. 2005. Landslide hazard and Risk zoning for urban planning and development. Proc. of the Int. Conf. on Landslide Risk Management, Vancouver 31 may-3 june 2005, pp. 199-235, Ed. Balkema,<br \/>Cruden, D.M. and Varnes, D.J., 1996. Landslides Types and Processes. In: A.K. Turner and R.L. Schuster (Editors), Landslides: Investigation and Mitigation. Transportation Research Board, National Academy of Sciences, Washington D.C., Special Report 247, pp. 36-75.<br \/>Flageollet, J.-C., 1994. The time dimension in the mapping of earth movements. In: R. Casale, R. Fantechi and J.-C. Flageollet (Editors), Temporal occurrence and forecasting of landslides in the European Community. Final Report, European Commission, Bruxelles, 1, 7-20.<br \/>Galli M., Ardizzoni F., Cardinali M, Guzzetti F. and Reichenbach P. (2008) \u2013 Comparing landslide inventory maps. Geomorphology 94, 268-289.<br \/>Guzzetti, F. and Cardinali, M., 1989. Carta Inventario dei Fenomeni Franosi della Regione dell&rsquo;Umbria ed aree limitrofe. G.N.D.C.I. Pub. n. 204. Map at 1:100,000 scale.<br \/>Guzzetti, F., Reichenbach, P., Cardinali, M., Galli M. and Ardizzone F., 2005. Probabilistic landslide hazard assessment at the basin scale. Geomorphology 72, 272-299.<br \/>Hansen, A., 1984. Landslide Hazard Analysis. In: D. Brunsden and D.B. Prior (Editors), Slope Instability. Wiley &amp; Sons, New York, pp. 523-602.<br \/>Heinimann H.R., Holtenstein K., Kienholz H., Krummenhacher B. &amp; Mani P., 1998. Methoden zur Analyse und Bewertung von Naturgefahren. Umwelt-Materialien Nr. 85, Naturgefahren, BUWAL, Bern, 248 pp.<br \/>Jones, D.K.C., 1992. Landslide hazard assessment in the context of development. In: G.J.H. McCall, D.J.C. Laming and S.C. Scott (Editors), Geohazards. Chapman &amp; Hall, London, pp. 117-141.<br \/>Kienholz, H., 1978. Maps of geomorphology and natural hazards of Grindenwald, Switzerland, scale 1:10,000. Arctic and Alpine Res., 10: 169-184.<br \/>Nardi, R., Pochini, A., Puccinelli, A., D&rsquo;Amato Avanzi, G. and Trivellini, M., 1985. Valutazione del rischio da frana in Garfagnana e nella Media Valle del Serchio (Lucca). 1) Carta geologica e della franosit\u00e0 degli elementi \u00ab\u00a0Gragnana\u00a0\u00bb, \u00ab\u00a0Piazza del Serchio\u00a0\u00bb, \u00ab\u00a0Casciana\u00a0\u00bb e \u00ab\u00a0Caserana\u00a0\u00bb (scala 1:10.000). Boll. Soc. Geol. It., 104: 585-599.<br \/>Nardi R., Pochini A. &amp; Allagosta M. (1990), La frana di Camporaghena (Lunigiana). Struttura del sistema di monitoraggio e risultati preliminari. Proceedings of the GNDT Meeting \u201cZonazione e riclassificazione sismica\u201d, Pisa, 443-460.<br \/>Panizza, M., 1990. The landslides in Cortina d&rsquo;Ampezzo (Dolomites, Italy). Proc. ALPS 90 &#8211; 6th ICFL, Switzerland-Austria-Italy, Aug. 31st-Sept. 12th, Universit\u00e0 degli Studi di Milano, pp. 55-63.<br \/>Pasuto A., Soldati M. &amp; Siorpaes C. (2005) \u2013 Carta Geomorfologica dell\u2019area circostante Cortina d\u2019Ampezzo (Dolomiti, Italia). Carta a scala 1:20.000, S.E.L.C.A., Firenze<br \/>Provincia Di Modena (2006), Piano Territoriale di Coordinamento Provinciale, Variante di adeguamento in materia di dissesto idrogeologico ai Piani di Bacino dei fiumi Po e Reno (adottato con deliberazione del Consiglio Provinciale n\u00b016 del 22\/02\/2006). Area programmazione e Pianificazione Territoriale, Area Ambiente e Sviluppo Sostenibile.<br \/>Raetzo H., Lateltin O. &amp; Tripet J.P., 2002. Hazard assessment in Switzerland \u2013 Codes of Practice for mass movements. Bulletin of Engineering Geology and the Environment, 61, 263-268..<br \/>Ryb\u00e1r, J., 1973. Representation of landslides in engineering geological maps. Landslide, 1: 15-21.<br \/>Santacana N., De Paz A., Baeza B., Corominas J., Marturi J. 2003. A GIS-based multivariate statistical analysis for shallow landslide susceptibility mapping in La Pobla de Lillet area (Eastern Pyrenees, Spain). Natural Hazards 30 (3): 281-295.<br \/>Van Westen, C.J., van Asch T.W.J. and Soeters R., 2005. Landslide hazard and risk zonation \u2013 why is it still so difficult?. Bull. Eng. Geol. Env.<br \/>Varnes, D.J., 1978. Slope movements: types and processes. In: R.L. Schuster and R.J. Krizek (Editors), Landslides: Analysis and Control. Transportation Research Board, National Academy of Sciences, Washington D.C., Special Report, 176, pp. 11-33.<br \/>Zezer\u00e8 J.L., Rodrigues M.L. Reis E., Garcia R., Oliveira S., Vieira G., Ferreira A.B. 2004. Spatial and temporal data management for the probabilistic landslide hazard assessment considering landslide typology. In. Lacerda W. et al (ed.) \u2013 Landslides. Evaluation &amp; stabilization. Vol.1. pp 117-125.<\/p>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p>\n<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/p><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t","protected":false},"excerpt":{"rendered":"<p>Risques Naturels Glissement de terrain Pr\u00e9par\u00e9 par le CERG, Centre Europ\u00e9en sur les Risques G\u00e9omorphologiques (Strasbourg, France) Un glissement de terrain correspond g\u00e9n\u00e9ralement \u00e0 un d\u00e9placement gravitaire de terrains meubles ou rocheux le long d&rsquo;une surface de rupture. Il s\u2019agit d\u2019un processus g\u00e9ologique appartenant \u00e0 la cat\u00e9gorie des \u00ab\u00a0MOUVEMENTS DE TERRAIN\u00a0\u00bb, terme d\u00e9signant un mouvement [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":8883,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_acf_changed":false,"footnotes":""},"acf":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v22.1 - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>Glissement de terrain - BeSafeNet<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/besafenet.net\/hazards\/landslides\/\" \/>\n<meta property=\"og:locale\" content=\"fr_FR\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Glissement de terrain - BeSafeNet\" \/>\n<meta property=\"og:description\" content=\"Risques Naturels Glissement de terrain Pr\u00e9par\u00e9 par le CERG, Centre Europ\u00e9en sur les Risques G\u00e9omorphologiques (Strasbourg, France) Un glissement de terrain correspond g\u00e9n\u00e9ralement \u00e0 un d\u00e9placement gravitaire de terrains meubles ou rocheux le long d&rsquo;une surface de rupture. Il s\u2019agit d\u2019un processus g\u00e9ologique appartenant \u00e0 la cat\u00e9gorie des \u00ab\u00a0MOUVEMENTS DE TERRAIN\u00a0\u00bb, terme d\u00e9signant un mouvement [&hellip;]\" \/>\n<meta property=\"og:url\" content=\"https:\/\/besafenet.net\/hazards\/landslides\/\" \/>\n<meta property=\"og:site_name\" content=\"BeSafeNet\" \/>\n<meta property=\"article:modified_time\" content=\"2024-06-11T13:07:33+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/landslides-1024x320.jpg\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"WebPage\",\"@id\":\"https:\/\/besafenet.net\/hazards\/landslides\/\",\"url\":\"https:\/\/besafenet.net\/hazards\/landslides\/\",\"name\":\"Glissement de terrain - BeSafeNet\",\"isPartOf\":{\"@id\":\"https:\/\/besafenet.net\/#website\"},\"datePublished\":\"2020-12-04T08:07:04+00:00\",\"dateModified\":\"2024-06-11T13:07:33+00:00\",\"breadcrumb\":{\"@id\":\"https:\/\/besafenet.net\/hazards\/landslides\/#breadcrumb\"},\"inLanguage\":\"fr-FR\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\/\/besafenet.net\/hazards\/landslides\/\"]}]},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\/\/besafenet.net\/hazards\/landslides\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\/\/besafenet.net\/el\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Risques\",\"item\":\"https:\/\/besafenet.net\/hazards\/\"},{\"@type\":\"ListItem\",\"position\":3,\"name\":\"Glissement de terrain\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\/\/besafenet.net\/#website\",\"url\":\"https:\/\/besafenet.net\/\",\"name\":\"BeSafeNet\",\"description\":\"\",\"publisher\":{\"@id\":\"https:\/\/besafenet.net\/#organization\"},\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\/\/besafenet.net\/?s={search_term_string}\"},\"query-input\":\"required name=search_term_string\"}],\"inLanguage\":\"fr-FR\"},{\"@type\":\"Organization\",\"@id\":\"https:\/\/besafenet.net\/#organization\",\"name\":\"BeSafeNet\",\"url\":\"https:\/\/besafenet.net\/\",\"logo\":{\"@type\":\"ImageObject\",\"inLanguage\":\"fr-FR\",\"@id\":\"https:\/\/besafenet.net\/#\/schema\/logo\/image\/\",\"url\":\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/besafe-logo.svg\",\"contentUrl\":\"https:\/\/besafenet.net\/wp-content\/uploads\/2020\/11\/besafe-logo.svg\",\"width\":1,\"height\":1,\"caption\":\"BeSafeNet\"},\"image\":{\"@id\":\"https:\/\/besafenet.net\/#\/schema\/logo\/image\/\"}}]}<\/script>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"Glissement de terrain - BeSafeNet","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/besafenet.net\/hazards\/landslides\/","og_locale":"fr_FR","og_type":"article","og_title":"Glissement de terrain - BeSafeNet","og_description":"Risques Naturels Glissement de terrain Pr\u00e9par\u00e9 par le CERG, Centre Europ\u00e9en sur les Risques G\u00e9omorphologiques (Strasbourg, France) Un glissement de terrain correspond g\u00e9n\u00e9ralement \u00e0 un d\u00e9placement gravitaire de terrains meubles ou rocheux le long d&rsquo;une surface de rupture. 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