Study on train running safety in railway switches and sharp curves considering wheel wear evolution

Train derailments are frequently reported during the long-term operation of the freight wagons. With this consideration, this paper aims to combine 3D quasi-static derailment analysis, dynamic simulation and reliability assessment to systematically investigate the running safety in railway switches and sharp curves considering the evolution of wheel flange wear (WFW). Firstly, an efficient and accurate wheel-rail contact geometry algorithm has been proposed to considering the large wheelset yaw angle and the variable rail cross-sections during derailment. Then a freight wagon-track (switch) dynamic interaction model is developed for derailment simulation. Finally, the Kriging method is presented to represent the dynamic responses of the derailment coefficient and wheel load reduction rate (WLRR) when consider the randomness of the input variables. The results show that severe WFW can significantly reduce the derailment limit. The WLRR in the switch exhibits strong nonlinearity with the input parameters. The probability of exceeding the limit of derailment coefficient in a sharp curve is greater than the probability of exceeding the limit of WLRR. This work provides a comprehensive understanding of the running safety and derailment behaviour in switches and sharp curves with the evolution of WFW, contributing to enhanced safety and efficiency in rail transportation.