Anti-plane dynamic response of a non-circular tunnel with imperfect interface in anisotropic rock mass

Abstract

In anisotropic rock mass, the dynamic response of a non-circular tunnel with imperfect interface is theoretically presented under an incidence of an anti-plane SH wave. For the anti-plane problem in anisotropic medium, three elastic constants can describe the characteristics of medium anisotropy according to the generalized Hooke’s Law. The wave function expansion method and the complex function are applied to express the wave fields with three unknown coefficients. By introducing the spring elastic model, the imperfect boundary condition around the tunnel lining can be satisfied to determine the coefficients. In numerical examples, effects of rock anisotropy and imperfect interface around the tunnel lining are discussed in detail, accompanied with incident angle and wave frequency. Analytical solutions show that both rock anisotropy and interface have considerable influence on the dynamic response of underground structures, which should be paid attention to for the design and construction of deep underground tunnels.