Research And Numerical Analysis Of Environment Vibration Induced By High Speed Railway Viaduct Track System In Loess Area

In recent years, the construction of high-speed railway in Northwest China is gradually increasing, making the environment vibration problem of high speed railway in loess area become the new focus of attention. Loess in our country wide distribution, large thickness, stratigraphic sequence is complete. On the basis of existing research results of environmental vibration, the dynamic characteristics of loess and loess region has itself, so the loess area, the high speed railway induced by environmental vibration problems become the new topic of research scholars. This thesis introduces the background of Zheng-Xi high speed railway viaduct bridge, using finite element theory and the finite element software ANSYS environment vibration induced by elevated rail system of high speed railway in loess area of numerical simulation, obtains the propagation law of environmental vibration in the loess region, finally carries on the comparative analysis of Zheng-Xi high speed railway viaduct bridge measured data, the general propagation disciplinarian of environmental vibration in the loess area of elevated bridge, provides the theory basis for the later practice. The main contents of this thesis are as follows:1. Summarized the development of high-speed railway and the environment vibration problem is put forward, and describes the mechanism of the environmental vibration and its influence, and then through the environment vibration research significance and the environment vibration research of the status quo at home and abroad and the research of environmental vibration method to describe the vibration environment.2. Briefly described the theory of environmental vibration analysis of two kinds of methods: direct method and the substructure method. This chapter mainly introduces the common use of the direct method, the finite element dynamic analysis of theoretical basis and analysis on environmental vibration finite element time history analysis method. Then, mainly describes the dynamic characteristics of loess of northwest loess region, for the subsequent finite element modeling of ground soil parameters and environment during the vibration propagation parameters for the dynamic analysis provides the basis.3. Based on the finite element theory, a section of the viaduct of Zheng-Xi high speed railway as the background, established the model of a simply supported beam overhead bridge by the application of the finite element software ANSYS, calculate the modal parameters of the bridge; to move the load simulation of high-speed train load, obtained by numerical simulation of dynamic response of high speed train bridge viaduct and corresponding supporting force.4. Established a three-dimensional finite element model of pier soil, and the soil by using viscous spring artificial boundary constraints, and then to obtain the support force for the input load, dynamic analysis of pier soil model. Finally, analysis of propagation law obtained the environment vibration in soil.5. Analysis in the loess area high speed railway environment vibration induced by elevated rail system propagation, compared with measured Zheng-Xi high speed railway obtained the environment vibration propagation law, obtained the universal law in the loess area high speed railway environment vibration induced by the propagation and characteristics.