Coupled thermal-hydraulic-mechanical model during rock damage and its preliminary application

Abstract: The thermal-hydraulic-mechanical (THM) coupling during the rock failure is of great significance for many engineering applications such as deep underground mining. A coupled THM model during the rock failure is proposed based on the conservation of mass and energy of solid and fluid when the damage is considered as a key factor that controls the THM coupling. The proposed THM model is firstly utilized to simulate the THM response of elastic medium; and it is validated by comparing the numerical results with the analytical solutions. Secondly, this THM model is employed to predict the coupled hydromechanical response of rock under different in-situ stress conditions. The numerical simulations indicate that, compared with the numerical results without hydromechanical coupling, the hydraulic pressure can not only facilitate the tensile damage and extend the range of tensile damage zone, but also restrain the occurrence of shear damage. Key words: rock damage; THM coupling; coupled THM model; numerical simulation