Effect of external geometry on the fatigue behavior of fillet-welded transvers stiffeners in ship building

Abstract

This dissertation describes a study of the fatigue behavior of stiffeners on flange fillet welded joints stressed perpendicular to the weld line. The study included an experimental phase in which the fatigue life and cracking behavior of stress concentration region was to determined. This experimental study concentrated on the fatigue behavior in the transition region low fatigue cycles. The finite element technique was used to determine the compliance of stress regions. The second phase of the study was the determination of the effect of wrapping in the stiffener-to-flange weld upon the fatigue life and the fracture mechanics (behavior) in stress intensified regions. The third phase of the study was to determine the impact of undercuts at the stiffener scallop and flange edge upon fatigue strength. It was found that wrapping the welds around the stiffener had no impact upon the fatigue life.