Abstract:Considering the effects of temperature on the coefficient of viscosity and void ratio of liquid,liquid flow caused by temperature gradient,heat flow on water potential gradient and heat flow due to thermal convection,based on Darcy¢s law,Fourier¢s law,the equations of equilibrium,the conservation equations of mass and energy are derived using two basic variables for unsaturated porous media,i.e. void ratio and volumetric liquid water content . And then the thermo-hydro-mechanical coupling model is applied to simulate the evolution law of unsaturated water flow in surrounding rock and concrete support of a claystone shaft with considering excavation and ventilation,by which the variations of pore pressure,temperature and saturation degree in claystone and concrete after tunnel excavation and ventilation are obtained. The study has significant effects for underground oil, nuclear waste disposal,design and construction for tunnel in cold regions.