Vibration Induced By Moving Train On Layered TI Elastic Or Saturated Halfspace

With the increasing train speed,the vibration problem induced by moving train is receiving tremendous attentionin respect of civil engineering and traffic engineering,which is mostly conducted under the assumption of isotropic soil.However,natural soil is usually characterized by obvious transversal isotropy(TI)due to sedimentary differentiation.It is of great theoretical significance and engineering value to study the TI ground vibration under moving train.This paper focuses on the vibration induced by moving train in layered TI foundations.The main work is listed as:1.Dynamic response of layered TI elastic half-space under the moving point load.First of all,the three-dimensional(3D)dynamic stiffness matrix for layered TI elastic half-space is established,which is employed to solve the dynamic response of layered TI elastic ground through direct stiffness method.Then,the influences of moving speed,material anisotropy and ground stratification on the dynamic response are analyzed with numerical calculations.Some useful conclusions are drawn.2.Dynamic response of layered TI saturated half-space under the moving point load.To begin with,the dynamic response of layered TI saturated ground is obtained with the derived 3D dynamic stiffness matrix.After that,numerical results are carried out to probe into the impacts of moving speed,material anisotropy,permeability,surface boundary condition and ground stratification on the dynamic response.Some beneficial points are obtained.3.Vibration of layered TI elastic foundation-track coupled system under moving train load.Based on the 3D dynamic stiffness matrix of layered TI elastic half-space given in this paper,the dynamic Green's function of layered TI elastic foundation is solved.And the layered TI elastic foundation-track coupled system is established,which can be used to study the effects of movingtrain speed,material anisotropy and ground stratification on the dynamic response.4.Vibration of layered TI saturated foundation-track-wheel coupled system under moving train load.The 3D dynamic stiffness matrix of layered TI saturated half-space is identified to cope with the dynamic Green's function.And the layered TI saturated ground-track-train coupled system is modeled to investigate the vibration problem under the dynamic load induced by the vertical irregularity between the wheel and the track.The influences of vibration frequency,material anisotropy,train moving speed and ground stratification are discussed.This paper provides an effective reference for both the application of layered TI elastic or saturated medium and the analysis of the foundation-track coupled system under moving trainwith high speed.