Abstract
Three-dimensional behavior of a cylindrical tunnel under an oblique incidence of seismic wave was theoretically analyzed. The lined structure is assumed to be a thick-walled elastic cylinder embedded in an infinite elastic medium and the seismic wave is assumed as a plane harmonic longitudinal or shear wave. The solutions are obtained by means of the eigenfunction expansions method. Numerical results show that the behavior of the transversal cross-section of tunnel is influenced by the ratio of the stiffness of ground mass relative to tunnel lining and is not influenced by the wavelength of incident wave. On the other hand, the behavior of longitudinal cross-section of tunnel is influenced not only by the ratio of the stiffness of the ground mass relative to tunnel lining but also by the wavelength along the tunnel axis. Therefore, seismic damage of mountain tunnel in weak rock is caused not only by the shear wave with its displacement component parallel to cross-section of tunnel, but also by the shear wave with its displacement component on the plane including tunnel axis.
