Effect of Weld Parameters on Effective Notch Stress at Weld Root and Toe of Load Carrying Cruciform Joints

Abstract

Cruciform joints in ships are prone to fatigue damage and the determination of type of weld plays a significant role in the fatigue design of the joint. In this paper, the effect of weld geometry on fatigue failure of load carrying cruciform joints in ships is investigated using Effective Notch Stress (ENS) approach. A fictitious notch of 1 mm radius is introduced at the weld root and toe and fatigue stress is evaluated. The effect of weld leg length (l) and weld penetration depth (p) on ENS at weld root and toe are determined. The critical weld leg length (l _cr) at which fatigue failure transitions from weld root to weld toe is investigated. An approximation formula for determination of the critical weld leg length considering weld penetration depth (p) is proposed.

Keywords

Crack initiation / Critical leg length / Cruciform joints / Effective notch stress / Load carrying joint / Root failure / T-welded joint / Weld penetration / Weld root / Weld toe

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