Innovative and cost-effective rail track construction using recycled rubber

Facing the high demand for faster and heavier freight trains in Australia, researchers and practitioners are endeavouring to develop more innovative and resilient ballasted tracks. In recent years, many studies have been conducted by the researchers from Transport Research Centre at the University of Technology Sydney (TRC-UTS) to examine the feasibility of incorporating recycled tyre/rubber into rail tracks. This paper reviews three innovative applications using recycled rubber products such as (1) a synthetic energy-absorbing layer for railway subballast using a composite of rubber crumbs and mining by-products, (2) using rubber intermixed ballast stratum to replace conventional ballast, and (3) installing recycled rubber mat to mitigate ballast degradation under the impact loading. Comprehensive laboratory and field tests as well as numerical modelling have been conducted to examine the performance of rail tracks incorporating these innovative inclusions. The laboratory and field test results and numerical modelling reveal that incorporating these rubber products could increase the energy-absorbing capacity of the track, and mitigate the ballast breakage and settlement significantly, hence increasing the track stability. The research outcomes will facilitate a better understanding of the performance of ballast tracks incorporating these resilient waste tyre materials while promoting more economical and environmentally sustainable tracks for greater passenger comfort and increased safety.