EPS Geofoam as a Wave Barrier for Attenuating High-Speed Train-Induced Ground Vibrations: A Single-Wheel Analysis

Abstract

Vibrations induced by high-speed trains in the ground are a common cause of concern in the urban railway lines due to construction of buildings and inhabitation of residents close to railway lines. The present study aims to evaluate the potential use of geofoam as an in-fill material for passive trenches to reduce the vibrations generated by railways. Considering the higher frequencies of railway vibrations in comparison with earthquake excitations, characterization of vibration attenuation efficiencies of geofoam in-filled trenches is done in the scale of peak particle velocities (PPV). A comprehensive study is conducted on the effects of buffer stiffness, geofoam density, and dimensions and location of the in-filled trench away from the railway track. Results indicate that having low buffer stiffness for the geofoam in-filled trenches are efficient in reduction of railway-induced ground vibrations. Grades of geofoam with smaller densities are observed to have better vibration attenuation characteristics as well. It is also characterized that the location of the trench close to the railway embankment results in an overall reduction in the vibration levels in the ground. A higher depth of in-filled trench is requisite, if the trench is located at higher distance from the track. It is ascertained that geofoam in-filled trenches are highly suitable for attenuating the train-induced vibrations in the native sub-soil.