Approach for the probabilistic fatigue assessment of welded joints based on the local geometry of the weld seam

Abstract

Welded joints show large variation of the weld toe geometry along the weld seam, which is one important reason for the comparably large scatter in fatigue life. Therefore, it is crucial to take the local geometry at the weld toe into account, to reduce the conservatism in fatigue assessment of welded joints. This study is based on the IBESS procedure for the calculation of the fatigue strength, whereby the evaluation of local geometrical parameters is carried out by means of 3D surface scans. The approach is validated against 26 fatigue test series. The fatigue life is in general overpredicted, whereas good agreement is achieved for high stress ratio ( ). A sensitivity analysis conducted with IBESS shows that weld toe radii ρ < 2 mm and flank angle α < 30° have a significant influence on the calculated fatigue strength. In contrast to this, no strong correlation between and the fatigue strength was determined experimentally in this study.

A method: multi-scale calculation life of welded beams with residual stress

“…In the meanwhile, the weld has great influence on the fatigue life of the structure [4]. Jan [5] studied the effect of weld geometry on the fatigue life of welded joints; Rajneesh [6] studied the microcrack propagation rule of welds; Xing [7] studied the fatigue failure mode transformation and control parameters of fillet welded aluminum alloys. Although the above researches are carried out from the multi-scale and multiple influencing factors of the weld, they are all based on the research of material properties.…”