Vertical Vibration Characteristic Analysis of Subway Train Height-Adjustable Slab Ballastless Track in Ground Fissure Environment

Objective Limited by engineering conditions such as the reserved connecting line on the hanging wall of the ground fissure, the existing ballastless track structure cannot meet the height adjustment function of subway track structure under large ground fissure deformation condition. Therefore, a height-adjustable slab ballastless track is needed. Method Considering the track structure characteristics in the ground fissure area, combining adjustable support with the frame plate, a slab ballastless track structure with height-adjustable support is proposed. A vertical vibration analysis model of the train-track system is established based on the finite element method, to discuss the mechanical properties and environmental adaptability of the ballastless track structure under ground fissure conditions. Result ＆ Conclusion The height-adjustable slab ballastless track is capable of adjusting up to 300 mm, ensuring the track smoothness under large ground fissure deformation condition; typical dynamic indicators such as the rail maximum vertical displacement meet the requirements of relevant specifications, verifying the reliable functions of the height-adjustable slab ballastless track; it is noticed that the daily maintenance and repair should focus on the state of the support joint, the seam in the middle slab supports should not be greater than 0.15 mm, so as to avoid the seams forming at the slab end supports.