An individual fatigue assessment approach considering real notch strains and local hardness applied to welded joints

Fatigue crack initiation in welded joints is a complex process influenced by various factors. Although these factors are discussed in the literature, the incorporation of them in assessment procedures is often insufficient or lacking. In this paper we present a novel assessment procedure based on the strain-life approach. The influence of the material in the weld area is considered by applying relations between hardness and fatigue properties taken from the literature. In addition, stress concentrations on the weld surface are captured realistically by using 3D-laser scans of the weld surfaces. The suggested approach is demonstrated on four specimens which are typically used in the construction of steel bridges and promising results are obtained. Nevertheless, more research is necessary in order to verify the exact accuracy of this method for the prediction of fatigue life.