Abstract
Local stress approach has been proposed as the fatigue strength evaluation method of welded joints without any classifications by the joint types and verified in the past studies. Generally, since it is difficult to directly measure the local stresses at the crack initiation point, ex. weld toe, the stress analysis helps us to estimate them, which requires establishing a model with weld toe geometry in fine mesh and great amounts of time. Thus, this study proposed the simple method for estimating the local stress in as-welded joints. In this method, the local stress at the as-welded toe is estimated from the stress at the toe finished by the grinding technique, where the strain gauge measurement is applicable. Fatigue tests and finite element analyses were conducted with out-of-plane gusset welded joints of as-welded and finished condition, respectively. Based on the results, the correlation of the local stress in the as-welded and finished joints was established. Consequently, it was demonstrated that the fatigue strength of the as-welded joints can be evaluated by using the local stress estimated by the proposed method.
