Research on Fatigue Analysis Method of Commercial Vehicle Body Welding Joint Based on Road Load Spectrum

The fatigue life of body welds plays a very important role in durability. In this paper, the body-in-white of a domestic commercial vehicle is used as the research object and the actual road test results are used as the benchmark to calculate the road test damage threshold. The fatigue analysis method based on force and stress was used respectively, and the parameters of the stress-based fatigue method of body weld joint were obtained by comparing the field test threshold. It is found that when the number of finite element nodes around the welding core is not less than 16, and the welding wire distance of 0.3 mm is used, the simulation results are closer to the real road test results. At the same time, it was found that the wire bond distance had little effect on the damage results.