Mechanical Analysis Of Highspeed Railway Slab Track

With the fast development of the modern high speed railway and urban rail transit, slab track has developed quickly with the characteristics of little maintenance, In the former slab track structure calculations, all the models had made simplification at different degree, and neglected the influence of the subgrade bed to the track structure. It couldn't reflect the real stress of the slab track completely. This paper took the subgrade based slab track as the research object, building up the mechanics analysis model, and making the systematic analysis.This thesis mainly contains the following aspect:(1) Overviewed the domestic and overseas research work about the slab track on the subgrade, and pointed out the main existing problems.(2) Introduced the structure types of the subgrade based slab track, and built up the mechanical models.(3)Presented two typical slab track arrangement mode of the expansion joint on the subgrade, and carried out the analysis and calculation by the finite models about the two different slab arrangement modes, the concrete bearing-breaking joint or butt-welled.(4) Calculated the reinforcement of the key structure of the unballasted track, by using of the flexion moment calculated by the beam and slab finite models of the slab track.(5) Analyzed the problems about transition section and its structure characteristics of the high speed railway, built up the structure model of the slab track and ballast track inside the tunnel near the transition section and then calculated the change of total stiffness of the track.(6) Developed the finite element model of the subgrade based slab track considering the moving axle loads, and analyzed the dynamic response of two kinds of track structures, the bearing-breaking joint and the butt-welled joint.(7) Analyzed the warping deformation of the track slab under two different temperature conditions that the range of the temperature is between -10℃and 10℃.In the end, at the foundation of summarizing the work of the thesis, put forward some problems of the topic that need to be studied profoundly.