Analysis On The High-speed Train Cabin Frame Injure

The equipment cabin which is installed under the high-speed train is a slender box-like structure. Equipment cabins in which large-scale equipment installed suffer are enclosed by thin-walled apron plates and bottom plates. Structural damage of the equipment cabin brings potential hazard to high-speed train operation. Equipment cabin frame is located in the position where apron plates and bottom plates are not connected, which is joint skeleton installed for linking apron plates and bottom plates. Statistical results show that some cases of fatigue crack are emerged in the equipment cabin bracket welding of CRH3travelling in Wuhan-Guangzhou line and Beijing-Tianjin line.This paper is based on actually measured dynamic stress on track of bracket, and combined with static strength, harmonic response, transient dynamic and modal analysis, studying the effect that aerodynamic loads of apron plates have on the equipment cabin bracket injure.The FE model of equipment cabin bracket is built with HYPERMESH and structural strength simulation analysis is done with ANSYS when the equipment cabin suffers vibration load and aerodynamic load. Then strength of bracket is evaluated based on standard of " Eurocode9:Design of aluminium structures_Part1-3: Structures susceptible to fatigue ". Equivalent stress and spectral response of frame are obtained through the stress-time history of bracket fatigue key positions which is got by means of dynamic stress test on track. Compare the results and preliminarily estimate the main factors of fatigue key positions.Modal analysis of equipment cabin bracket is done to determine natural frequencies and the corresponding modes of each modal; Then harmonic response analysis and transient dynamic analysis are done to explore stress response of bracket under the condition of resonance and different influence that aerodynamic loads have on bracket stress under different operating conditions(the intersection of two vehicles and situation when vehicles passing in and out tunnel).This paper reveals the reasons of equipment cabin frame injure through simulation analysis and field tests. The study methods mentioned above provide guidance for forecasting fatigue life of components under resonance state and analyzing failure mechanisms.