Analytical solution of mechanical response in cold region tunnels under transversely isotropic freeze–thaw circle induced by unidirectional freeze–thaw damage

During the operation stage of cold region tunnels, isotropic surrounding rock in a freeze–thaw circle suffers long-term unidirectional cycles and gradually transforms into transversely material, which induces variation stress displacement distribution tunnels. Aimed at this phenomenon, an analytical solution mechanical response tunnels under circles induced by damage is proposed. The derived two different states circle: 1 ) unfrozen state (state TU) 2 frozen TF). In addition, lining with analyzed. transformation from material leads to increase lining, especially for significant TF. Finally, influence deterioration coefficient degree anisotropy on increases linearly as decreases, while it nonlinearly decreases. smaller is, greater rate is. Moreover, TF much than that TU. Both decrease 1.0 increasing suffered rock, and, thus, induce stresses lining. has