Numerical simulation of the dynamic behaviour of a degraded insulated rail joint

Abstract

Due to the significant discontinuity in stiffness and geometry, the insulated rail joint (IRJ) is considered as one of the weakest parts in the track structure. The wheel-rail impact over a joint may lead to track deterioration and increased maintenance costs. The impact load is believed to be closely associated with the dynamic behaviour of track and conditions of track components at the joint section. In this paper, the dynamic behaviour of a typical IRJ in the Dutch railway network is studied numerically. A three dimensional finite element (FE) IRJ model is set up and an explicit time integration scheme is employed to simulate a hammer test conducted on the IRJ. The simulated frequency response functions (FRFs) of the IRJ are then calculated and some typical resonant behaviours can be deducted. Based on the numerical model, the influence of various deterioration types on the dynamic behaviours of IRJ are predicted under the controlled conditions.