Experimental Study on Reutilization of Waste Rubber Chips with Sheetpiles as a Coupled-Wave Barrier to Reduce Ground-Borne Vibrations

Abstract

Purpose: Environmental and man-made vibrations due to various sources have become an environmental issue in recent years. Wave barriers such as open and in-filled trenches have been commonly used in the mitigation of these vibrations. Even though the open trench has exhibited better performance than the others, it may not be applicable or feasible in many cases. Therefore, soft and stiff barriers have been used for the same purpose. The present study aims to reveal the vibration isolation performance of not only single barriers such as rubber chips in-filled trenches and sheetpiles but also a novel barrier, rubber chips-sheetpile coupled barriers. Methods: Rubber chips and sheetpiles were employed as soft and stiff wave barriers, respectively. The screening effectiveness of rubber chips, sheetpiles and their coupled form was examined through comprehensive field tests. Vibrations having frequencies in the range of 10–80 Hz were generated by a state-of-the-art mobile seismic shaker and measured by highly sensitive acceleration and velocity pickups in the absence and presence of these wave barriers. The effectiveness of the wave barriers was quantitatively determined. Results and conclusion: While the sheetpile was more effective than rubber chips at low frequencies, the case was vice versa at higher frequencies. However, the coupled wave barrier outperformed other barriers in each case. If one barrier could not provide the required amount of isolation or is only effective within a limited range of frequency, using a coupled barrier with the installation of the other may significantly provide better vibration isolation.