Temperature-Stress Analysis of Rock-Shotcrete Structure under High Temperature Cooling Effect

Abstract

Take the diversion tunnel located in geothermal area as engineering background, the coupled temperature-stress analysis of rock-shotcrete structure with high temperature was performed under immersion action of cold water. The Physical and simulation experiment show that temperature evolution of rock-shotcrete structure can be classified into three stages, which are initial rapid decay stage, deceleration decay stage and the equilibrium stage; The stress simulation shows that the sharp change of stress will occur in the shotcrete layer during the first stage, and maximum principal stress is mainly manifested as tensile stress, which will easily lead to tensile failure of the shotcrete layer; the displacement simulation shows that the rock-shotcrete structure takes on overall shrinkage deformation in each temperature stage, and it is most obvious for shotcrete layer. The deformation of rock plate will not stop until temperature reaches stable state. Such kind of deformation law will weaken constraint on the shotcrete material, and therefore lead to stress relief in the shotcrete layer.