Study on the influence of damage characteristics of longitudinal ballastless track on the dynamic performance of train‑track‑bridge coupled systems

High-speed railway bridges are inevitably damaged under external loads during operation, which may lead to abnormal vibration of trains, and even threaten running safety. Aiming at the practical problem of high-speed railway longitudinal ballastless track structure damage, based on the train-track-bridge interaction theory, a three-dimensional coupled vibration model of a train-track-bridge was developed using the finite element method. The dynamic response calculation program (TTBCS) was developed using the Newmark-β numerical calculation method. The model and program were used to calculate and analyze the influence of damage to the main components of high-speed railway ballastless track-bridge structure on the dynamic response of the system, including fastener failure, interlayer component damage, and bearing vertical stiffness degradation. The results show that the fastener failure significantly influences the vertical interaction of the wheel-track. The number of fastener failures should not exceed one pair otherwise there is a risk of derailment. When the CA (cement and emulsified asphalt) mortar layer and the slide layer void length exceeds the critical value, the dynamic irregularity of the track-bridge system significantly increases the vertical vibration of the wheel-track system. The critical value of void should be given more attention to in the operation of high-speed railways. The vertical dynamic performance of the train is not sensitive to the change in vertical support stiffness within a certain range of stiffness values but within a certain operation speed range, adjusting the bearing stiffness can play a certain vibration isolation effect.

---

Opracowanie rekordu ze środków MEiN, umowa nr SONP/SP/546092/2022 w ramach programu "Społeczna odpowiedzialność nauki" - moduł: Popularyzacja nauki i promocja sportu (2022-2023)