Effect of thermo-hydro-mechanical coupling on the evolution of stress in the concrete liner of an underground drift in the Cigéo project

Abstract The French National Radioactive Waste Management Agency (Andra) is in charge of studying the disposal high-level and intermediate-level long-lived waste (HLW ILW-LL) a deep geological repository (Cigéo project) within host formation Callovo-Oxfordian claystone (COx). heat emitted from packages induces thermo-hydro-mechanical (THM) coupling structural elements rock. This study focuses on behavior concrete lining an ILW-LL cell subjected to THM loading during its construction operational phases. mechanical rock represented by elasto-visco-plastic model taking into account anisotropies stiffness strength. coupled formulation based Biot theory. Different simulations including full HM with or without creep COx have been performed show effect thermal load (generated packages), water seepage strain stress evolution liner. results preponderant role state liner phase, while moderate that not significant.