Sustainability of Vibration Mitigation Methods Using Meta-Materials/Structures along Railway Corridors Exposed to Adverse Weather Conditions

Abstract

Noises and vibrations caused by operating transport systems can seriously affect people’s health and environmental ecosystems. Railway-induced vibrations in urban settings can cause disturbances and damages to surrounding buildings, infrastructures and residents. Over many decades, a number of mitigation methods have been proposed to attenuate vibrations at the source, in the transmission path, or at the receiver. In fact, low-frequency or ground-borne vibration is turned out to be more difficult to be mitigated at source, whilst some attenuation measures in propagation path can be applicable. To broaden the mitigating range at the low-frequency band, the applications of meta-materials/structures have been established. In railway systems, periodic structures or resonators can be installed near the protected buildings to isolate the vibrations. Despite a large number of proposed attenuation methods, the sustainability of those methods has not been determined. Based on rational engineering assumptions, the discounted cash flows in construction and maintenance processes are analysed in this study to evaluate lifecycle costs and the quantity of materials and fuels, as well as the amount of carbon emissions. This study is the world’s first to identify the efficacy and sustainability of some transmission path attenuation methods in both normal and adverse weather conditions. It reveals that geofoam trenches and wave impeding blocks are the most suitable methods. Although metamaterial applications can significantly mitigate a wider range of lower frequency vibrations, the total cost and carbon emissions are relatively high. It is necessary to significantly modify design parameters in order to enable low-cost and low-carbon meta-materials/structures in reality.