Influence of unsteady temperature on the stress field of a deep buried circular lining tunnel: Fid-Bau Portal

Influence of unsteady temperature on the stress field of a deep buried circular lining tunnel

Cheng, Qian-xiang / Lu, Ai-zhong / Yin, Chong-lin

Abstract This paper presents a method to solve the stress field of a deep buried circular lining tunnel under the combined action of an unsteady temperature field and in situ stress. The solution of the temperature field can be reduced to a problem of solving the unsteady temperature field in the composite medium under the first type of boundary conditions in the infinite domain, and the distribution of the temperature field in the lining and surrounding rock can be obtained by the Laplace transform method. Through the stress boundary condition of the inner boundary of the lining, the continuous condition of the contact surface and the zero displacement boundary condition at infinity, equations expressed by the boundary values of the analytical functions are established. Then the temperature stresses caused by temperature changes can be obtained. By superimposing these stresses with the stresses caused by in situ stress, the total stresses inside the lining and surrounding rock can be obtained. This article compares the analytical solutions with the numerical solutions obtained by ANSYS. In addition, the influence of temperature field on the stress field of lining and surrounding rock is discussed in the case of temperature decrease and increase through calculation examples.