Dynamic analysis of pavement and multi-layered transversely isotropic saturated ground system subjected to a rectangular moving load

摘要

The three dimensional vibration of pavement and ground coupled system subjected to a rectangular moving load are investigated analytically. The pavement is simplified as an infinitely long orthogonal anisotropic elastic plate and the materials of subgrade are assumed to be multi-layered and transversely isotropic soils obeying Biot's dynamic poroelastic theory. The governing equations of the system are solved in the transformed field domains of moving space. Considering the mixed boundary condition at the surface of the first layer, the fixed boundary condition at the bottom of the last layer and that the stress and displacement at the interface of the layers are continuous, analytical solutions of vertical displacement and excess pore water pressure in the form of integral are derived by using the Fourier transform, and the dynamic responses in the time domain are obtained through the fast Fourier transform (FFT). The results show that a moving load with high velocity will generate a larger dynamic response than the lower velocity load, the transversely isotropy and the characteristics of layered soils have remarkable influence on the vertical displacements and excess pore water pressure. The traditional design method taking ground soil as homogeneous isotropic soil is unsafe for the case of R_E<1 and R_G<1.