DYNAMIC STRESS RESPONSES TO HIGH-SPEED MOVING LOAD ON ELASTIC SATURATED SEMI-SPACE GROUND

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.