Plastic deformation of curved rail at rail weld caused by train–track dynamic interaction

This paper presents a dynamics model of a vehicle coupled with a track to investigate the material deterioration of a welded rail profile at a curved track. A three-dimensional finite element model is built up to investigate the plastic deformation of the rail at welds. In the finite element model, the welded rail section, heat affected zone (HAZ) and base metal are considered to have different material properties. The normal pressure and tangential force distribution in the contact area, which are calculated by the dynamics model and the FASTSIM algorithm, respectively, are utilized as the inputs to the finite element model. The influence of the amplitude (wave depth) of rail weld irregularity is explored. The numerical results show that welded rail surface irregularity causes localized weld batter in a welded rail section and HAZ. The amplitude of the irregularity at the rail weld has a great effect on the plastic deformation.