Application of a ship-routing fatigue model to case studies of 2800 TEU and 4400 TEU container vessels

Ship structures will always be subjected to and suffer from fatigue damage and fracture. However, we can become better at utilizing the materials and the structures and operating them more wisely, leading to less maintenance, extended service life and enhanced safety if we can improve the fatigue damage prediction. In this study, a fatigue model useful for ship routing is presented. Similar to the ship-routing design for the expected time of arrival and fuel reduction, the objective here is to demonstrate the possibility and benefits of ship route planning which lead to a reduction in fatigue damage accumulation. In the context of ship fatigue route planning, uncertainty analysis of the fatigue assessments of container ships is discussed. The proposed ship-routing fatigue model is employed in case studies on two container vessels to illustrate the possible benefits to the fatigue safety of ship structures. Sea environments in the application are obtained from hindcast wave data and a spatiotemporal wave model. The results show that the fatigue damage of the studied container ship structures could be decreased by more than 50% if awareness and knowledge of fatigue in ship route planning are employed.

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