Abstract: This paper used the analytical layer element method to analyze two-dimensional dynamic response of multilayered saturated subsoils subjected to a vertical time-harmonic load based on Biot consolidation theory. Starting with the governing equations of plane strain problem in Cartesian coordinates, ordinary differential equations can be obtained from partial differential equations through the Fourier-Laplace transform, and the analytical layer element for a single saturated soil layer is established. The global stiffness matrix for multilayered saturated subsoils is assembled according to continuity conditions of adjacent layers and boundary conditions. Actual solutions are obtained by taking Fourier-Laplace inverse transform. The results of numerical calculation are in good agreement with the existing solution in literature. More numerical examples are designed to analyze the effects on vertical displacement due to the circular frequency, force depth and soil stratification. Numerical results show that the vertical displacement increases firstly and then decreases with the increases of circular frequency; the vertical displacement at the load point presents a crest and is influenced by the characteristic of topsoil greatly.

Key words: multilayered saturated subsoils, plane strain problem, vertical time-harmonic load, analytical layer element method