A 2.5D peridynamic model for turnout rail crack propagation under wheel rolling contact action

Based on the OSB PD (Ordinary State-Based Peridynamics) theory, a 2.5D PD model for rail crack propagation in railway turnout was proposed. First, a 2D model for rail crack propagation in railway turnout was constructed, with two kinds of 2.5D additional constraints for crack opening and cross-section proposed on the basis of the 2D model. A 2.5D PD model for rail crack propagation in railway turnout could thus be established. Then, a fatigue crack propagation experiment was carried out on the U71Mn turnout rail material. The bond fatigue failure condition of the turnout rail material was established based on the experimental results. Finally, the accuracy of structural deformation and bond fatigue failure condition was verified. The simulation results for rail crack propagation were compared with field observations and then analyzed in detail. These results showed that the proposed 2.5D PD model could be used to accurately simulate the characteristics and rules for rail crack propagation in railway turnout.