Dynamic Analysis Of Subgrade Retaining Wall For High Speed Railway

The west region of China was hilly and large height difference. It cost too much to construct bridge on whole railway, so high filled embankment was a better selection. The eastern region was flat, but the land acquisition is difficult. Too much occupation of cultivated land wasn’t conducive to sustainable economic development. In the city, the high embankment slope not only occupied land, but also increased air pollution when the vehicle after or the wind blows, which against the air pollution control policy now. Therefore, in order to make the structure more stable, less land occupation, reducing dust pollution, better durability, the roadbed side slope has been replaced by the retaining wall. With the increasing use of retaining wall structure, the analysis of the force, especially the stress and deformation under train loads, should be given more attention.This paper mainly through calculation and numerical simulation analysis of ANSYS,analyzed high-speed train dynamic load transfer law in the ballast and ballastless track structure, and studied the soil pressure and the dynamic response of gravity and cantilever retaining wall under train load and the change of the pattern of the different factors.(1) Firstly, summarized the current domestic and foreign research situation of train load and retaining wall, And put forward the main research content of this article.(2) A brief introduction to the Coulomb and Rankine soil pressure theory. Through gravity and cantilever retaining wall as example, the soil pressure of the train loads was calculated, respectively consider layered filling and the second crack appearing on the surface in both cases the wall back soil pressure of form, size and distribution were compared using conversion soil Coulomb method and dynamic stress method of soil pressure value difference.Then calculated the soil pressure and the point of resultant force of gravity and the cantilever retaining wall in different speed and wall heights.(3) Premising the wheel-track action force which is achieved through vehicle-subgrade coupling theory as the analysis loads, the 3-D dynamic finite analysis model on ballasted track(slab ballastless-track) and subgrade is presented. Considered the connection way between different elements and the material nonlinear of track and subgrade, and applied artificial visco-elastic boundary simulating the infinite boundary of subgrade, the simulation analyze on dynamic response of track-subgrade is realized by the ANSYS.(4) With the parameters of track subgrade of high-speed railway as the basis, using the established track subgrade retaining wall model for dynamic analysis, the acceleration,displacement and dynamic stress change rule for reference, analyzes the train load in the ballasted track and ballastless track subgrade dynamic response in the transfer law.(5) Analysis of different wall in high load, subgrade slope height, distance, the running speed of the train, the gravity and the cantilever retaining wall back acceleration, dynamic displacement and earth pressure of retaining wall with the transfer to the dynamic changes,corresponding changes have.(6) In the end of the thesis, and puts forward some problems to be further studied in this paper.