Ground vibrations induced by high-speed trains moving on layered near-saturated ground using 2.5D FEM

Abstract

An improved 2.5-dimensional finite element model is developed to investigate ground vibrations induced by high-speed trains moving on layered near-saturated soil. The accuracy of the model is validated using a theoretical solution. The effects of the train speed, soil type, and saturation on the vibration acceleration, displacement, and excess pore pressure are evaluated by comparing soft- and hard-layered near-saturated and saturated soil models. The findings suggest that the effect of saturation on the ground vibration acceleration and displacement is minimal when the train speed is below the critical speed of the soil. The vibration acceleration, displacement, and excess pore pressure in the soft-layered soil are higher than those in harder soil. Compared to harder layered soil, saturation has a more prominent influence on vibration acceleration and displacement in softer soil, whereas its influence on excess pore pressure is low. The rebound of the excess pore pressure at the saturated soil interface is more pronounced than that at the near-saturated interface. The effect of saturation on excess pore pressure is independent of the train speed.