Abstract: 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 tyre 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 modeling have been conducted to examine the performance of rail tracks incorporating these innovative inclusions. The laboratory and field test results and numerical modeling reveal that the incorporation of 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 economic and environmentally sustainable tracks for greater passenger comfort and increased safety.

For his lifetime contributions to Civil Engineering with special focus on rail infrastructure and ground improvement, Prof Indraratna was felicitated by the Australian Government as a Member of Order of Australia. He was also the recipient of the prestigious Jose Ibarra Foundation’s 6th International Civil Engineer award in 2024 in Madrid, Spain, the first Australian to receive this pinnacle recognition.  

Currently, Buddhima Indraratna is a Distinguished Professor of Civil Engineering and the Director of Transport Research Centre, at University of Technology Sydney. Formerly, he was a Distinguished Professor and the Founding Director of Australian Research Council’s Training Centre for Rail Infrastructure (ARC ITTC-Rail) at the University of Wollongong. His contributions to geotechnical and railway engineering have been acknowledged through numerous national and international awards, including 1st Ralph Proctor Lecture and 4th Louis Menard Lecture of the International Society of Soil Mechanics and Geotechnical Engineering. His numerous international awards include Thomas Telford Premium by the Institution of Civil Engineers (UK), Robert Quigley Award by the Canadian Geotechnical Society, and the Medal of Excellence for life-time contributions by the International Association of Computer Methods and Advances in Geomechanics. Buddhima is a Fellow of the prestigious Australian Academy of Technological Sciences and Engineering (FTSE), Fellow of the Institution of Engineers Australia (FIEAust), Fellow of American Society of Civil Engineers (FASCE), Fellow of Australasian Institute of Mining and Metallurgy (FAusIMM), and Fellow of the Geological Society of UK (FGS).  He is a Chartered Professional Engineer of Australia, United Kingdom, and Sri Lanka.