Assessment of fatigue capacity in the new bulk carrier and tanker rules

During 2004 and 2005 new design rules for bulk carriers and tankers were proposed. The rule proposals were developed in two different projects: The Joint Bulker Project denoted JBP and the Joint Tanker Project denoted JTP. The result from this is that two very different procedures for fatigue assessment of ship structures have been developed. In this paper, the two procedures are reviewed with respect to fatigue capacity. The proposed JBP and JTP analysis procedures have been compared with 200 fatigue test data where the test specimens were subjected to 5 different loading conditions. The procedures are also compared for a typical welded connection subjected to different mean stress levels.