Dynamic Response of Tunnel Structures in Inhomogeneous Medium under SH Wave: Shear Modulus in Quadratic Functional Form

The task of this work is to study the scattering of SH waves by homogeneous tunnel structures in an unbounded inhomogeneous medium. The shear modulus is assumed to be a function of coordinates (x,y). A two-dimensional scattering model is established. Selecting different inhomogeneous parameters, the medium has different properties, expressed as a rigid variation. The stress concentration phenomenon of the structure is analyzed for material design. Based on the complex function theory, the expressions of wave field in the tunnel are derived. The stress concentration phenomenon on the tunnel is discussed with numerical examples. The distribution of dynamic stress concentration factor on the inner and outer boundaries is analyzed under different influencing factors. Finally, it is found that the distribution of dynamic stress concentration factor is significantly affected by the inhomogeneous parameters and reference wave numbers of the medium.