Recycled rubber tracks underlay slow ballast wear and cut maintenance

A two-year field trial conducted on Sydney Trains’ Chullora freight corridor has demonstrated that a recycled rubber track underlay significantly reduces ballast degradation and maintains track stability under heavy loading. Developed and patented by University of Technology Sydney (UTS) researchers, the system uses tyre-derived rubber “cells” filled with waste materials and covered by recycled rubber grids made from worn mining conveyor belts. Compared to conventional track sections, the rubber-reinforced areas showed markedly less ballast pulverization and slower track settlement, as documented in a peer-reviewed study published in the Canadian Geotechnical Journal. This innovation effectively protects the ballast by absorbing shocks and spreading axle loads more evenly, thereby extending the life of the track structure and reducing maintenance needs such as tamping. The recycled rubber underlay changes the traditional load path by compressing elastically under train wheels, which lowers peak stresses on ballast stones and distributes forces over a wider area of the underlying soil. This prevents soil settlement and weakening of the track foundation, critical for