Crts Ii-type Non-ballasted Track Structure System Construction Phase Behavior Analysis

CRTS II slab ballastless track, based on Bogl longitudinal connected ballastless track, has been used in Beijing-Tianjin Intercity Railway and Beijing-Shanghai Express Railway in our country. However, the situation of the foreign countries is of great discrepancy to our country, and it is important create our home-made ballastless track technology based on the achievements of the predecessors in foreign countries. This paper will analysis the behavior of different component of the ballastless track in every stage from construction to operation.First of all, a finite space mechanical model of CRTSⅡslab ballastless track on the soil formation is established by using finite element software-ABAQUS, and the results of the calculation model have been compared with the results of the design. In this model, the factors of steel ordinances of slab, baste stitch on track slab and contact are considered.Secondly, a time axes from construction to operation of the slab ballastless track is established and the value of the load in every period of time is determined.Finally, the influences of different loads to CRTSⅡslab ballastless track during every period of time are obtained:1) In construction stage, before track slab is installed, cycling warping deformation of base slab will be occurred because of the periodic temperature gradient load. When rail have been installed, the warping deformation of track slab will reduce and the warping stress of track slab will increase.2) When construction is completed, before the high-speed railway is put into operation, the baste stitch on track slab will have cracking problem under the load of lower temperature, the cyclical variation of temperature gradient will cause track slab have warping deformation and gapping problems. 3) The cracking problem of baste stitch on track slab have great influence on base slab especially in stage of operation when vehicle load is located in the edge of track slab, base slab will have cracking problem because of the load of lower temperature or negative temperature gradient.Therefore, heat insulation work and surface clean work should be taken during the construction stage in order to ensure the different component of the ballastless track has good caking property; the quality of base slab should be improved and the maintenance is needed in order to ensure security.