{"id":20982,"date":"2026-10-02T09:00:02","date_gmt":"2026-10-02T07:00:02","guid":{"rendered":"https:\/\/navier-lab.fr\/?p=20982"},"modified":"2026-09-28T11:21:02","modified_gmt":"2026-09-28T09:21:02","slug":"thesis-defense-wenqing-cai","status":"publish","type":"post","link":"https:\/\/navier-lab.fr\/en\/thesis-defense-wenqing-cai\/","title":{"rendered":"Thesis defense \u2013 Wenqing Cai"},"content":{"rendered":"<p style=\"text-align:justify;\">Wenqing CAI, PhD student in the Geotechnics team of the Navier laboratory, will defend his thesis \u201c<em>Gas transfer in compacted bentonite\/sand mixtures<\/em>\u201d on 6 October 2026 at 2 pm in Amphitheatre Caquot (also available online via <a href=\"https:\/\/teams.microsoft.com\/meet\/332584225296896?p=ubvKgdmpcOtkFedEEa\" target=\"_blank\" rel=\"noopener\">this link<\/a>). The defense will be held in English.<\/p>\n<p style=\"text-align:justify;\">The thesis jury consists of the following members:<\/p>\n<ul style=\"list-style:none; margin:0; padding:0;\">\n<li style=\"margin:0 0 0.5em 0;\"><span style=\"color:#E2A034; margin-right:0.5em;\">\u25cf<\/span>Mahdia HATTAB, Universit\u00e9 de Lorraine, Reviewer<\/li>\n<li style=\"margin:0 0 0.5em 0;\"><span style=\"color:#E2A034; margin-right:0.5em;\">\u25cf<\/span>Olivier CUISINIER, Universit\u00e9 de Lorraine, Reviewer<\/li>\n<li style=\"margin:0 0 0.5em 0;\"><span style=\"color:#E2A034; margin-right:0.5em;\">\u25cf<\/span>Fr\u00e9d\u00e9ric COLLIN, Universit\u00e9 de Li\u00e8ge, Examiner<\/li>\n<li style=\"margin:0 0 0.5em 0;\"><span style=\"color:#E2A034; margin-right:0.5em;\">\u25cf<\/span>Enrique ROMERO, Universitat Polit\u00e8cnica de Catalunya, Examiner<\/li>\n<li style=\"margin:0 0 0.5em 0;\"><span style=\"color:#E2A034; margin-right:0.5em;\">\u25cf<\/span>Jean TALANDIER, Andra, Examiner<\/li>\n<li style=\"margin:0 0 0.5em 0;\"><span style=\"color:#E2A034; margin-right:0.5em;\">\u25cf<\/span>Patrick DANGLA, \u00c9cole Nationale des Ponts et Chauss\u00e9es, Examiner<\/li>\n<li style=\"margin:0 0 0.5em 0;\"><span style=\"color:#E2A034; margin-right:0.5em;\">\u25cf<\/span>Yu-Jun CUI, \u00c9cole Nationale des Ponts et Chauss\u00e9es, Thesis supervisor<\/li>\n<li style=\"margin:0 0 0.5em 0;\"><span style=\"color:#E2A034; margin-right:0.5em;\">\u25cf<\/span>Jean-Michel PEREIRA, \u00c9cole Nationale des Ponts et Chauss\u00e9es, Invited member<\/li>\n<\/ul>\n<style>\n.resume-toggle summary::-webkit-details-marker{display:none;}\n.resume-toggle summary{list-style:none;}\n.resume-toggle .resume-arrow{display:inline-block;transition:transform .15s ease;}\n.resume-toggle[open] .resume-arrow{transform:rotate(90deg);}\n<\/style>\n<details class=\"resume-toggle\">\n<summary style=\"cursor:pointer; color:#1e73be; font-weight:600;\"><span class=\"resume-arrow\">\u25b8<\/span> Abstract<\/summary>\n<p style=\"text-align:justify;\">Compacted bentonite\/sand mixtures are recognized as optional sealing\/backfilling materials in the deep geological repository for long-lived high-level radioactive wastes worldwide. In this context, it is important to guarantee that the gas production after the repository closure does not jeopardize the barrier system. This study investigates the hydro-mechanical-gas transfer behavior of compacted bentonite\/sand mixtures by experimental and numerical approaches. The compression behavior during static compaction for sample preparation was firstly analyzed. A factor defined as the contribution of bentonite to the overall compressibility was introduced to clarify the formation of sand skeleton at low bentonite fractions. Then, the swelling pressure, hydraulic conductivity and gas injection tests were conducted under constant-volume condition. Besides, the local heterogeneity of compacted mixtures was determined experimentally. The effects of bentonite fraction, dry density, sand nature and heterogeneity on the hydro-mechanical-gas transfer behavior was analyzed. The dominant mechanism of gas transfer after gas breakthrough was determined. The materials satisfying the Andra\u2019s requirements for a sealing core were defined. Furthermore, the hydro-mechanical behavior upon suction-controlled oedometer loading was investigated. Finally, a numerical modeling focusing on the mixture heterogeneity was conducted to analyze the gas transfer. An original method was proposed to describe the development of gas preferential pathways.<\/p>\n<\/details>\n","protected":false},"excerpt":{"rendered":"<p>Wenqing CAI, PhD student in the Geotechnics team of the Navier laboratory, will defend his thesis \u201cGas transfer in compacted bentonite\/sand mixtures\u201d on 6 October 2026 at 2 pm in Amphitheatre Caquot (also available online via this link). The defense will be held in English. The thesis jury consists of the following members: \u25cfMahdia HATTAB, [&hellip;]<\/p>\n","protected":false},"author":188,"featured_media":20971,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[266,251,291,299],"tags":[],"class_list":["post-20982","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-actualites-en","category-annonces-en","category-annonces-geotech-en","category-soutenances-de-these-en"],"acf":[],"_links":{"self":[{"href":"https:\/\/navier-lab.fr\/en\/wp-json\/wp\/v2\/posts\/20982","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/navier-lab.fr\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/navier-lab.fr\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/navier-lab.fr\/en\/wp-json\/wp\/v2\/users\/188"}],"replies":[{"embeddable":true,"href":"https:\/\/navier-lab.fr\/en\/wp-json\/wp\/v2\/comments?post=20982"}],"version-history":[{"count":1,"href":"https:\/\/navier-lab.fr\/en\/wp-json\/wp\/v2\/posts\/20982\/revisions"}],"predecessor-version":[{"id":20983,"href":"https:\/\/navier-lab.fr\/en\/wp-json\/wp\/v2\/posts\/20982\/revisions\/20983"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/navier-lab.fr\/en\/wp-json\/wp\/v2\/media\/20971"}],"wp:attachment":[{"href":"https:\/\/navier-lab.fr\/en\/wp-json\/wp\/v2\/media?parent=20982"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/navier-lab.fr\/en\/wp-json\/wp\/v2\/categories?post=20982"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/navier-lab.fr\/en\/wp-json\/wp\/v2\/tags?post=20982"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}