INFLUENCE OF INCOMPLETE PENETRATION SIZE ON FATIGUE CRACK INITIATION POINTS OF LOAD-CARRYING CRUCIFORM WELDED JOINTS

Abstract

This paper investigates influence of incomplete penetration size on fatigue crack initiation points of load-carrying cruciform welded joints. The investigation was performed by fine meshed FEM using Effective Notch Stress Approach. As a result, to prevent fatigue crack initiated from welded root when the plate thickness is about 34mm, incomplete penetration size should be less than 10% of the plate thickness, and the influences of incomplete penetration size increase with an increase of the plate thickness. Also, a reduction of the stress at the weld root by increasing the weld size is not expected when the plate thickness is thick and welding becomes an unequal leg length welding.