Research on Selection Method of Fatigue Monitoring Points for Welding Structure of Rail Vehicles Based on Structural Stress Method

Selecting fatigue monitoring points for welding structure in a PHM system or a fatigue bench testing for rail vehicles is a complex and difficult problem. In this paper, a method for selecting fatigue monitoring points for welding structure based on structural stress method is proposed. Firstly, static strength method is selected to obtain the weak points of the welded structure. Secondly, the structural stress method with the standard load spectrum and the actual load spectra is used to achieve more fatigue weak points, and the cumulative damage ratio of various weak points are calculated as well. A selecting procedure is then used to determine the ultimate locations of the fatigue monitoring points based on the fatigue weak points above. Finally, a rail vehicle is taken as an example to verify the method. The result shows that the position of the fatigue monitoring points for the complex welded structure of rail vehicle can be obtained effectively by the method.