Abstract
In welded structures, fatigue cracks usually initiate from the welded toe and propagate to the plate thickness direction in the cross section. Stress distributions along the crack path are required in order to estimate the precise fatigue life prediction by using fracture mechanics. But stress distributions along the path are not obtained in practical structural design because the shell elements are used in finite element analyses at the design stage. A simple estimation method of the stress distribution normal to cross section at weld toe, which corresponds to the fatigue crack path in case that cracks grow from a weld toe, is proposed in this paper. Input data for this estimation are calculation results of FEM with shell element and geometrical conditions (radius, flank angle of toe and plate thickness). The validity of this method is confirmed by comparing estimation results with ones by finite element analyses with fine solid elements.
