394 / 2022-02-03 11:54:25

Mechanical and vibration properties of CRTS II track structure with fastener failure and subgrade settlement

Fastener failure; Subgrade settlement; High-speed railway; Mechanical property; Vibration

With the increasing of the service time of the high-speed railway infrastructure, the probability of damage of the under-track structure, especially the fasteners and subgrade, will increase significantly. Subgrade settlement will cause stress changes in the track structure. Moreover, if the fasteners on the upper part of the track fail, the combined action of them will cause irreversible structural damage to the track structure, which will seriously threaten the safe operation of high-speed trains. In order to study the internal damage of the track structure under the combined action of fastener failure and subgrade settlement, this study takes the type II track structure as the research object, and systematically studies the internal dynamic displacement amplitude variety of the track slab and support layer with the failure of single and multiple fasteners, and the influence of different settlement amplitudes on the track structure when a single fastener fails. It is found that the failure of fasteners and the increase of the settlement amplitude will significantly increase the dynamic response of the track structure. The joint action will aggravate the local deformation of the track structure, and even plastic deformation may occur in some areas. Therefore, for the safety of the track structure, special attention must be paid to fasteners and subgrade settlement.