Research On The Consistency Load Spectrum And Test Method Of The Key Structural Parts Of EMU

With the rapid development of Chinese regional economic and the high-speed rise of the urban-group, In order to meet the requirements of inter-city rail transit,CRH6 intercity EMU came into being at a historic moment. Theapplicationof the key structuralparts are directly related to the operation quality and safety. The structure loading spectrumis thefoundation of establishing the evaluation standard of structual reliability test and proceed strength tests. In order to guarantee the fatugue strength of the load bearing parts can meet the real operation conditions. We need to analyses the load-time history of the train, and compilethe load spectrun ofkey structures with high confidence which under true running situation, so as to be used in laboratory fatigue test.In this paper, Itook the axle-box, traction-rod and anti-roll-bar as the research object. ANSYS software was applied to calculatethe finite element models of the struture parts mentioned above,and the outcome showed their static strength and fatigue strength were all satisfied,then we gotthe fatigue critical parts of the axle box and the load identification position of each load system.Combined with practical experience, the dynamic stress measureing point positionof the axle box and a more accurate load identification scheme for different structures were determined, which can be used in actual measurement. IMC data collection apparatus was employed to gather data from the Dazhou-Chengdu railway. Special data analysis software nCode,compiled by England, was used to process, summarize, conclude and arrange the data. Combination of the load-strain transfer coefficient obtained in the laboratory calibration test, the measured load spectrum and stress spectrum of the key structures on the line were established.For axle-box, the stress transfer coefficients were computed for the fatigue key points in each load spectrum by using ANSYS software. The load spectrum was optimized by the damage consistency test,through the comparison of the measured stress spectrum and recognition of the stress spectrum of the damage. As for traction-rod and anti-roll-bar, The load spectrum is optimized by using the safety factor specified in the existed codes. Then the fatigue test plan was developed according to the optimization of thekey structural parts with high confidence of the load spectrum.