Research On The Influence Characteristics Of Wheel/Rail Roughness Noise In High Spee Railway

With the large-scale construction and operation of high speed railway,the problem of noise influence is becoming more and more prominent.It is imminent to carry out the research on noise control technology of high-speed railway system.Wheel/rail roughness is an important factor which affects wheel/rail noise,and affects wheel re-profilin and track maintenance.A lot of work has been carried out in the research and Simulation of wheel rail roughness test and simulation abroad,and the limit spectrum of wheel rail roughness in Europe has been set up.However,our country started late in wheel rail roughness measurement and noise impact research,and lacked much systematic test data,and it is not applicable to the roughness limit spectrum of rail and wheel in China.The main conclusions of this paper are as follows:(1)The research status of wheel/rail noise and wheel/rail roughness at home and abroad is summarized.The calculation of wheel and rail vibration and sound radiation involves the theory of structural vibration,the theory of modal analysis and the theory of sound radiation based on the boundary element.The wheel/rail vertical excitation model was established,and the contact stiffness characteristics of wheel and rail and the contact filtering characteristic of wheel/rail were analyzed.(2)The wheel roughness testing equipment and method are introduced.The wheel roughness of the main EMU in China is measured and statistically analyzed,and the wheel roughness spectrum characteristics of different vehicles under different working conditions are studied.Wheel re-profiling can effectively reduce the roughness level of the short band(below 30mm)of the wheel.The overall level of comprehensive effect of wheel roughness by each band roughness level,a lathing cycle in different periods of different dominant bands.At the same time,the extreme weather,such as wind and sand,will also have a significant influence on the roughness of wheel and rail.According to the multiple EMU wheel before and after multiple cycles of surface roughness tracking test results,referring to the standard of BS EN ISO 3095:2005 ? Railway applications-noise emission-rail roughness measurement related to rolling noise generation?,combined with the simulation calculation of wheel/rail radiation noise,initially given China EMU wheel surface roughness limit spectral value.(3)The track roughness testing equipment and test method are introduced.The rail roughness of main high-speed railway lines in China is tracked and measured for a long time,and the surface roughness of different track sections is obtained.The rail vibration modal test and the dynamic attenuation characteristic analysis of the rail are carried out.Statistical analysis of rail roughness in different regions shows that the roughness level of short wave band(63 mm below)is low in Central China,and the roughness level of medium long wave band(100 mm above)in eastern China is relatively low.According to the tracking test results of multiple grinding cycle roughness of multiple lines,referring to the standard of BS EN ISO3095:2005 ? Railway applications-noise emission-rail roughness measurement related to rolling noise generation?,combined with the simulation calculation of wheel/rail radiation noise,initially given China's rail roughness limit spectral value.(4)The finite element model of the wheel is set up and the natural frequency and vibration mode of the wheel are obtained through the modal analysis of the wheel.The modal superposition method is used to calculate the frequency response of the wheel,and the radial response of the tread,the axial response of the rim and the axial response of the spoke are obtained under the radial force of the nominal force at the nominal contact point.Based on the wheel/rail noise model,the direct boundary element method is used to solve the acoustic radiation characteristics of the external sound field of the wheel,and the influence of wheel/rail roughness on the wheel/rail radiation noise is analyzed,which provides a basis for the formulation of the wheel roughness limit spectrum and the track roughness limit spectrum.