Fatigue strength determination of ship structural joints

Spectacular accidents at sea which have happened for a few last years show that hull structures of contemporary sea-going ships are not perfect and must be systematically improved. Fatigue strength is one of the groups of strength problems which affect design of contemporary ship's structures and greatly contribute in their improvement process. In this paper several approaches to estimation of fatigue life of hull structural elements are presented. In practice the some approaches based on nominal stresses, "hot spot" stresses or notch stresses which constitute the basis for fatigue life determination by using σ-N design curves are applied. In this paper the existing proposals have been critically analyzed and their drawbacks (often hidden) presented.