The surface wave attenuation zone of periodic composite in-filled trenches and its isolation performance in train-induced ground vibration isolation

Abstract

The mitigation of surface wave is the primary concern in ground vibration isolation due to the energy of wave propagation in the soil being concentrated in the surface wave. Herein, a composite in-filled trench composed of expanded polystyrene (EPS) and concrete was proposed and arranged as a periodic structure. The surface wave attenuation zone of the proposed periodic composite in-filled trenches and its application to the isolation of train-induced ground vibration were investigated in this paper. A field test of ground vibration induced by an elevated intercity railway was conducted in order to obtain acceleration data and their corresponding dominate frequencies. Then, a two-dimensional finite element mode using COMSOL was developed to reveal the dispersion relationship and attenuation zones of the surface wave in layered ground. The influence of the different parameters of the periodic composite in-filled trenches on the reduction performance of train-induced ground vibration was analyzed numerically. The results indicate that an effective reduction performance of the proposed periodic composite in-filled trenches can be achieved when their attenuation zone coincides with the frequencies of the surface waves. Moreover, the proposed composite periodic structure illustrated an improvement in ground vibration isolation compared to periodic in-filled trenches comprising concrete or EPS only.