Abstract:Based on Biot¢s dynamic theory,the method of complex variable functions is used to solve the problem of scattering of elastic waves by circular cavity with lining in saturated soil. The equation of steady-state Biot wave motion is decoupled and reduced to 3 Helmholtz equations by introducing in 3 potential functions. The lining is treated as isotropic elastic material,the control equation of which is decoupled and reduced to two Helmholtz equations by introducing two potential functions. Utilizing the solutions of the potential functions,the expressions of the displacements,stresses and pore pressures of saturated soil and those of the displacements and stresses of lining can be obtained. By using the boundary conditions and continuity conditions between saturated soil and lining structure,the unknown coefficients in the potentials can be determined. The wave number and thickness of lining are analyzed in this paper.