Analysis On Vertical Dynamic Responses Of The Double Block Track Of CRTS Ⅰ Layed On Soil Formation And The Parametric Study

At present, we are focusing on large-scale construction of the high-speed railway and the special line for passenger transport, while the ballast-less track have the prominent advantage of better structure stability, better structure durability, better stiffness uniformity,better track regularity, less maintenance and relative mature of technology, and has gradually become the first choice of the high-speed railway. However, the researches on the ballast-less track layed on the soil formation are still at the stage of theoretical research and analysis test, while the double block track layed on the soil formation is more backward in technique than slab track, so the force analysis on slab track layed on the soil formation and parameter study have an important practical significance.This thesis focuses on the the double block track of CRTS I layed on soil formation.through the compares among three models, composite beams,entitys and beam and slab structure, according to Finite element theory, the beam and slab structure model of double block track layed on the soil formation is built, by ANSYS. Then, the transient dynamic analysis on CRTS I ballast-less track is done. In this paper, through the comparison of the runtime structure vertical dynamic status of a group of wheels to two groups of wheels, we study on two groups of wheels of the bogie next, which rolling along the rails.Through calculating all parts in soil subgrade under the force of a bogie, analysing the response of the various dynamic status, we analyse the deformation rule of ballast-less track, in the condition of fastener failure of buckles and the transform of Rail structure parameters.The major work of parameters study is the analog calculation,which is done corresponding to the different fastener stiffness,different elastic modulus of track bed,different elastic modulus of the water-hardening concrete supporting layer and different elastic modulus of the foundation.Then,it analyse the vertical dynamic response of each layer of the structure. The analysis showed that with the increment of the fastener stiffness, the vertical displacement of the rail reduce, and the vertical acceleration of each layer reduce, too, while both moments of the ballast increase. So, the reasonable stiffness of fastener is about 60kN/mm; the more reasonable elastic modulus of the slab is nearly 35000MPa; The higher the foundation coefficient, the smaller sedimentation and the better to upper structure. However, considering objective conditions, the eventually data should be decided carefully.