Analysis of crack retardation effects and crack path in ship structure members on different routes

Abstract

The ship size has been rapidly increased in recent years. Consequently, many aspects of ship structural safety have been concerned, i.e. fatigue strength. Since fatigue cracks are found in the early stage of a ship’s service life, it might be that the classical cumulative fatigue rule is insufficient to consider the effects of many uncertain factors, such as variable wave environment loads. The wave load history hinges on the short-sea history. It means that the accuracy of fatigue assessment is affected by the used wave model. There are several established wave models, which could be used to simulate wave load history as in the real ocean conditions. In this paper, wave load histories of a 2800TEU container ship are generated by two different wave models. It is used for crack propagation analysis in the changing routes and trades. The result in the simulated crack propagation lives is examined and discussed