Coupled thermo-hydro-mechanical model and 2D FEM analysis for FEBEX in-situ test

In the study on geological disposal of high level radioactive nuclear waste,it was important to establish the model of coupled thermo-hydro-mechanical processes and to simulate the laboratory and in-situ tests by numerical methods.Up to now many computation codes for THM coupling analysis had been made up in western countries and Japan.But in China the similar codes developed by Chinese was few.For this reason,through establishing the momentum equilibrium equation,the continuity equation for water,the energy balance equation and the elastoplastic matrix,one coupled thermo-hydro-mechanical model for saturated-unsaturated porous media,in which the swelling pressure could be considered,was suggested,and the relevant two dimensional code of finite element method was developed by the author.Taking the FEBEX in-situ test for geological disposal of high level radioactive nuclear waste as the modeling object,a numerical analysis was carried out.The measured data and the computed values of relative humidity,temperature,total water head and compressive stress in several parts are compared with each other,and some conclusions for the rightness of the code and the analyzed results were obtained.