Prediction of rail non-uniform wear – Influence of track random irregularity

Abstract

A numerical model for the prediction of rail non-uniform wear evolution is proposed. The vehicle-track coupled dynamics model, Kalker's variational method and the material wear model developed by the University of Sheffield are combined to acquire the distribution of rail wear at each contact patch. Rail wear distributions for particular cross-sections at regular intervals are calculated by a new sampling and accumulation strategy. Moving average smoothing and spline interpolation are employed to obtain a relatively smooth rail surface. Based on the proposed model, the non-uniform wear evolution of a 100 m-long rail and its effect on wheel-rail dynamic interaction are investigated based on a Chinese high-speed vehicle (CRH2 EMU) that runs on the straight-line section of a ballastless track (CRTS I). The simulation results indicate that the wear band is almost parallel to the rolling direction and shows an extended trend during the wear evolution. The distribution of the rail wear area along the wheel rolling direction shows agreement with the wear number. The average wear area after the passage of one vehicle remains constant even though the wear is continuously updated. Non-uniform rail wear has a minimal effect on the wheel-rail vertical dynamic interaction but has a significant influence on the wheel-rail lateral interaction.