Shallow Trenches and Propagation of Surface Waves

Abstract

The effect of the placement of shallow trenches of semi-circular or rectangular shape in the path of propagation of surface waves is studied. The ground is represented as a linear elastic halfplane, the vehicle as a point load vibrating in a wide range of frequencies, and an open air trench is interposed between the vehicle and the receiver. A two-dimensional direct boundary element method approach defined in the frequency domain is used to numerically investiate this problem. The results obtained indicate that trenches are beneficial in reducing the amplitude of vibration only in a narrow band around the mid-frequency range and in all other cases a large amplification of the dynamic signal is obtained. The actual shape of the trench is of minor importance.