Vibration Fatigue Life Analysis On Rigid-flexible Coupling Of CRH3 Carbody

Nowadays, at home and abroad, there is almost blank in the researching of high-speed train body strueture fatigue strength and analysis under high-speed dynamical loads. Foreign standards focus on constant amplitude, but in fact the stochastic variable dynamic loads cause the service locomotive carbody structure fatigue failure, because welding line is the danger zone of the carbody structure.Therefore, carbody welding line fatigue life prediction under stochastic variable dynamical loads is of important engineering significance.After reducing mass of high-speed train body,frequency domain of stochastic dynamic loads increase vertical vibration acceleration of vehicle which widened by track irregularity, and arouse the carbody elastic vibration in high frequency through bogie, sothat produce an effect on riding quality and fatigue life of vehicle. So the research of carbody structure fatigue life evaluation has become one of most important research projects. In this condition, the paper uses one exploratory method to evaluate carbody structure fatigue life simulation with Multibody System dynamics and Finite Element Analysis by absorbing some reference newer algorithm. According to Craig-Bampton fixed boundary mode synthesizing analysis method, the finite element model is established by the powerful software HYPERMESH and transformed into model neutral file by MSC.PATRAN,MSC.NASTRAN which is accepted by the multi-body dynamics analyzing software MSC.ADAMS. Structural stress method needs the load spectrum for fatigue life prediction,which is collected in the simulation of body-bogie rigid-flexible coupling in high-speed under dynamical loads.This paper mainly about, finite element analysis of carbody strueture, Multibody System dynamics simulation of high-speed train body and fatigue life prediction based on structural stress method.(1) First solving the constraint mode of CRH5-TP (3rd trailer), base on those theory. Comparing with the body mode of high-speed train CA250-M2S, the reliability of solving constraint mode of large finite element model is verified. Stochastic variable dynamic loads are analyzed in brief.(2) Base on the first step, load spectrum is collected by Rain-flow counting method of feature of statistics after CRH3-TC02 carbody analyzed.(3) Fatigue life assessment.