中文摘要：

对承受高速移动荷载的饱和多孔地基动应力响应开展了解析理论研究。引入势函数，进行Helmholtz代换，通过傅里叶变换得到了承受矩形分布的竖向与水平向移动荷载的三维饱和地基动应力的基本函解，数值积分求解逆变换，进而得到移动荷载下饱和地基动应力响应的理论解。基于饱和多孔介质的动应力理论解，分析了移动荷载速度及频率的动应力响应，进一步分析了水平及竖向移动荷载耦合作用下饱和地基的动应力。理论分析表明，荷载速度及其频率诱发地基动应力水平的放大效应，动应力水平随荷载移动速度增大呈现指数型放大效应，移动速度接近剪切波速时动应力水平达到峰值，而荷载速度与频率引发的动应力放大效应随地基深度增大而增强。考虑水平动载的耦合效应，地基的动剪应力和水平向正应力水平显著增大，而竖向动正应力变化不大。

英文摘要：

This work aims to gain an insight into dynamic stress responses in saturated poroelastic subsoil subjected to high-speed moving loading by using an analytical method. By introducing scalar potential functions, Helmholtz decomposition theorem, Fourier transforms and inverse Fourier techniques are used to achieve an analytical solution to the three-dimensional dynamic stresses in the saturated poroelastic ground, subjected to rectangular moving vertical and horizontal loads. Numerical results are obtained by performing inverse Fourier transforms. The deviatoric stress paths under moving loads are presented. The analytical results are used to account for the influence of dynamic load parameters （e.g., velocity of moving load, frequency of moving load, horizontal load） on the shape of stress path. It has been found that the speed and frequency of a moving load essentially enhance dynamic stress responses. The dynamic stress magnitude is exponentially increasing with the increasing speed of a moving load. When the load moving speed approaches the inherent Rayleigh wave speed, the dynamic stress tends to reach its peak value. The increasing magnitudes caused by moving load speed and frequency are increasing with the increase of ground depth. Coupling the influence of horizontal moving load, the shear stress and horizontal stress are increasing apparently whilst the increasing magnitude of vertical stress is relatively low.