Original Article

Finite element analysis of the mechanical behaviour of insulated rail joints due to impact loadings Nirmal Kumar Mandal Insulated rail joints (IRJs) are safety-critical components in the signalling system of rail corridors. They are subjected to dynamic loads generated by heavy rolling-stock/track- system interactions and degrade faster than the other components of the rail track. Degraded IRJs diminish the reliability of the signalling system, thus posing a serious threat to the safety of rail operations. Therefore, there is a pressing need to closely examine the failure mechanisms of the end posts made of insulated material and inserted into the discontinuity in the rail at IRJs with a view to improving their service life, reliability and efficiency. Only a limited literature is available that examines different materials for IRJ end posts, and these primarily focus on contact pressure and contact stress distributions in the vicinity of the end post, disregarding the damage to the rail ends and end post materials. In this paper, a detailed three-dimensional finite element analysis procedure is carried out to quantify plastic deformation and material damage to the end post and railhead materials of IRJs due to a wheel load above that of the shakedown limit of rail steel. A modified Hertzian contact pressur