ASSESSMENT OF FATIGUE STRENGTH OF CRUCIFORM WELDED JOINTS FAILING FROM WELD ROOTS UNDER OUT-OF-PLANE BENDING

Abstract

  When a fatigue crack originates and propagates from weld root, detection of the crack is difficult. Therefore, its prevention is important from the point of maintenance view. A lot of studies have been performed on the fatigue strength of cruciform welded joints failing from weld roots under axial loading conditions. But the real structures have a lot of parts in which out-of-plane bending applies. In this study, the difference between fatigue strength when the cruciform joints sustain out of plane bending and axial force, and the fatigue strength evaluation formula under combined loads are discussed through fatigue tests on model specimens and fatigue crack propagation analyses.