Research On Vibration And Noise Radiation Of Noise Barrier Structure On Bridge Under Train Wheel-rail Load

The noise of high-speed railway has brought serious troubles to the residents along the line.Setting up noise barriers along the railway line is one of the effective measures to solve this problem.However,during the noise reduction service of the noise barrier,its own structure vibrates under the load of the train wheel and rail,which is very likely to cause instability and damage..In addition,in the case of vibration,the noise barrier will also become a noise source,radiating noise to the surrounding environment.Therefore,this thesis is funded by the National Natural Science Foundation of China(51878672)-"Research on the optimal design theory and method of high-speed railway noise barrier structure under aerodynamic load".Taking the noise barrier of the bridge section of the ganshen railway as the research object,the numerical simulation method is used to comprehensively analyze the vehicle-induced vibration response and structure noise radiation law of the noise barrier.The research work carried out is as follows:(1)Based on the multi-body dynamics theory,the CRH2 high-speed train model is established by SIMPACK software.According to the inverse fast Fourier transform,the time-domain signal of the German low-interference orbital spectrum is inverted as the excitation source of vehicle body vibration.(2)Based on the ANSYS APDL module,the finite element model of the track and bridge-noise barrier is established by using the parametric command flow language,and the SIMPACK identifiable flexible body file is generated through the substructure analysis module.Combined with the SIMPACK flexible track module,ANSYS and SIMPACK can realize the co-simulation of the coupled vibration of the train-track-bridge structure,and analyze and calculate the wheel-rail time-course force when the train passes through two noise barriers of different heights at different speeds under the condition of single-vehicle driving.(3)Based on the transient dynamics theory,the ANSYS Workbench module is used to establish the vehicle-induced vibration dynamic analysis model of the high-speed railway noise barrier,and the wheel-rail time history force is loaded on the rail to calculate and analyze the structural vibration law of the bridge noise barrier under different working conditions.(4)Based on the acoustic boundary element theory,the acoustic boundary element model of the noise barrier of the high-speed railway bridge section was established by the noise analysis software LMS Virtual.lab.Two-dimensional sound field distribution of structure-borne noise under vehicle-induced vibration of noise barrier,sound pressure level spectrum and attenuation law of setting field points.There are 48 figures,15 tables and 84 references.