Dynamic compaction-induced ground vibration screening using dual open and geofoam-infilled barriers in layered soil media: physical field experiments and numerical simulations

Abstract

Dynamic compaction activities induce high-energy wave packets into the soil medium that cause public nuisances, necessitating the adoption of vibration mitigation measures. Most experimental studies have focused on the usage of single-wave barriers that demand nonviable depths. The current study employs a combination of field tests and numerical simulations to analyse the isolation potential of dual open and geofoam-infilled barriers in the mitigation of impact-induced ground vibrations. The experimental procedure consists of dropping a mass using a mechanical loading device. The amplitudes of vertical velocities were recorded before and after the installation of barrier systems. Furthermore, a numerical model simulating plane-strain behaviour was developed using PLAXIS 2D and verified through a direct comparison with experimental results. A detailed parametric investigation was then conducted to examine the influence of different contributing parameters in mitigating dynamic compaction-induced ground vibrations. Furthermore, the effectiveness of geofoam was compared with other infill materials, viz. bentonite, ceramsite, concrete and sand–rubber mixture. Strong evidence was observed for the implementation of dual barriers in preference to single barriers. The optimum depth of 0.5L_R and 0.7L_R (where \({L}_{\text{R}}\) is Rayleigh wavelength) was observed for dual open and geofoam-infilled barriers to screen 75% of vertical vibrations. An average amplitude reduction ratio of 0.24 and 0.27 was noted for the EPS15 (expanded polystyrene geofoam with a density of 15 kg/m³) and ceramsite-filled dual barriers for a depth of 0.7L_R. Furthermore, the isolation efficiency of EPS48 was noted to decline by 61% compared to EPS15 geofoam.