Study On Load And Stress Spectrum Of 400km/h Wheel Axle

The wheel and axle is one of the main components of the high-speed train,which is closely related to its operation safety.In recent years,with the rapid development of China's high-speed trains,the vehicle speed has been further improved,and we also put forward more strict requirements on the wheel and axle fatigue problems,meanwhile,the establishment of load spectrum as well as the determination of its distribution features are the important bases of the fatigue evaluation and reliability design of the wheel and axle.Therefore,this paper takes the Instrumented wheel set of the CRH380A as the research object,and analyzes the load spectrum of the wheel and axle by combining simulation with experiment.This paper studies the following aspects:(1)Through the finite element simulation calculation,we get the load and stress output characteristics of the plate,and identify the vertical load and lateral load separately by selecting the load identification points reasonably,so as to reduce the interference caused by crosstalk.According to the UIC510-5 standard,the static strength and fatigue strength of the wheel before and after punching are evaluated,and the results show that the strength of the wheel meets the requirements.(2)Make the Instrumented wheel set,design the calibration test plan,complete the static calibration test,and get the vertical and lateral load stress transfer coefficient by processing the test data.(3)Based on the measured data,the train's straight-running,curves-running,starting,parking and other working conditions are distinguished,and the time-domain characteristics of various bridges circuits under different working conditions are analyzed.The vertical and lateral loads are used to identify the measured data of bridge circuits,and the load spectrum is compiled under different working conditions at different speeds.The influence of velocity variation on load spectrum distribution features is analyzed.(4)According to the compiled load spectrum,its distribution features are fitted.Chi square test and R test are used to make hypothesis test for the fitting results.Finally,it is confirmed that both vertical and lateral load spectra are subject to truncated normal distribution.Analyzing the change of the parameters of probability density functions fitted under each working condition in different speeds,and the changing trend by using regression analysis method,finally inferring the wheel and axle load spectrum at 400 km/h speed.(5)Based on the measured data,the stress spectrum of each section of the axle at different maximum speeds is compiled,and the distribution is fitted.Based on the hypothesis test,the stress spectrum of each section of the axle at 400 km/h speed is deduced,and the fatigue strength of the axle is evaluated according to the linear cumulative damage theory,and the results show that the axle meets the needs of service.