Vertical Dynamics Analysis And Parameter Study Of CRTS ⅠSlab Ballasted Track On Soil Formation

With the development of high-speed railway in the world, the ballastless track forms have been more widely used. Currently, the track forms of high-speed passenger railway line in China are mostly ballastless track. Compared to traditional ballasted track, the ballastless track has the advantage of less maintenance, better structural stability, better structural durability, better track regularity, better stiffness uniformity and relative mature of technology. However, the study of ballastless track on the soil subgrade is not deep enough and the relevant experience is still less, so the force analysis on slab ballastless track on the soil subgrade and the parameter study have important practical significance.The CRTS I slab ballastless track structure on soil subgrade is the research object of this thesis and it has established the vehicle-track dynamics coupled model in this thesis. Specifically, the thesis uses the ADAMS/Rail software to establish vehicle model and the wheel/rail coupled model and enter Germany track interference spectrum as the track irregularity; At the same time, based on the finite element principle, this thesis uses finite element software ANSYS to establish slab model of CRTS I slab ballastless track on soil subgrade. Through the established model, it has studied the effect of the speed variation on the vehicle and the CRTS I slab ballastless track structure and analyzed the effect of the track parameters variation on rail track structure. The analysis of the calculated results leads to the following conclusions:1. This thesis has analyzed the vehicle and track dynamic vibration response at the speed of250km/h and the track structure dynamic response after changed the driving speed. The researches indicate that the increase of the traffic speed has very significant effects on the vehicle and track structure. Namely, with the increase of the driving speed, the wheel-rail vertical force and the body vertical acceleration increases, and the acceleration and vertical displacement of rail, orbital plate and base plate also increase. What’s more, the vertical and horizontal bending moments of the orbital plate and base plate also increase with the driving speed, and the moment value increases significantly at the speed of250km/h.2. The track structure has been affected by five parameters, such as the stiffness of fastener, the elastic modulus of CA mortar, the elastic modulus of the slab, the elastic modulus of base and the elastic coefficient of foundation. Based on the consideration of the rail structure, this thesis suggests the stiffness of fastener is50kN/mm～70kN/mm; the elastic modulus of the slab is35000MPa-40000MPa, the elastic modulus of CA mortar is100MPa-300MPa; the elastic modulus of base plate is30000MPa-35000MPa; the coefficient of foundation is60MPa/m～80MPa/m.