Nonlinear behavior of geological and engineered barriers

Among geo-materials, Clay is one of the most investigated as engineering barrier. In this paper, the fully coupled Thermo-Hydro-Mechanical response of a multiphase clay and geological barrier is analyzed. In nuclear waste disposal site, because of heat source existence, engineered and geological barrier are unsaturated media. A suction based-formulation of fully coupled behavior of a deformable unsaturated porous medium under heating is used. The nonlinear behavior and phase change (vapor and liquid ) are considered. The coupling effects of skeleton, suction and temperature via the concept of state surface of void ratio and degree of saturation are included. Above theories of THM coupling were been applied in Code Aster in order to simulate the behavior of buried waste disposal. The objective of this section is estimation of geological barrier (GB) and engineering barrier(EB) behaviors under heat distribution. (authors)