J.F. Shao, Zhan Yu, Minh-Ngoc Vu
This paper presents numerical modeling of deformation and damage evolution in host rock for deep geological disposal of radioactive waste, incorporating hydromechanical gas coupling. Fundamental constitutive relations governing partially saturated porous media are stablished. The host rock demonstrates elastoplastic behavior with damage initiated bymicrocrack propagation. Subsequently, a localized cracking process is represented using a phase-field model that incorporates the effects of plastic deformation and pore fluid pressures. The proposed hydromechanical gas and phase-field coupling model is implemented within the finite element framework. Three-dimensional numerical simulations of an in-situ gas injection experiment are conducted. The resulting hydromechanical responses, including liquid and gas pressures, plastic deformation, and damage are presented and discussed.