Study On Fatigue Strength Of Carbody And Its Local Chassis Of High-Speed Train

Carbody is the main structure of high speed train,Multiple types of alternating load are applied to carbody when the train is running.In order to improve the safety and reliability of carbody, fatigue research of carbody is very important. Thehigh-speed car body is bulky,it is difficult to carry out fatigue tests on the body as a whole based on the current major domestic vehicle test bed experimental conditons.So it is extremely important to carry out fatigue testing research on carbody part,especially the chassis which is under the most complex load conditions.Based on the overview of car body strength theory research, test research and car body strength standard research at home and abroad.This paper put a more in-depth discussed about how to accurately determine a reasonable constraints and equivalent load when the local component in the test.It coulddetermine more realistic response the carbody chassis’s boundary conditions through contrasting concern regional’s trends in stress and deformation by finite element analysis of vehicle model and the chassis locally model.Based on the minimal total error theory of stress on the region of interest to obtaining for the equivalent load of the vehicle chassis components in the test through contrasting the stresses in the region of interest in the vehicle model and the chassis locally model.Based on the train system dynamics mode.The thesis obtained load time history of the car body’s primary load under basic condition,different wheel wear situation and fault condition by dynamic simulation. Then it finished rain-flow counting and expansion processing, and got the full load spectrums of car body’s primary load. It provides theoretical guidance for fatigue strength design of car body according to the response of dynamic stress of car body in different load excitation.