ABSTRACT
For developing more precise fatigue strength assessments, the authors have analysed big data about ship location, heading angle, speed, etc. obtained by AIS from nearly 25,000 ships over roughly a three-year period in order to identify the standard operating route for each ship type and size. The authors also have derived the corresponding wave scatter tables representing the sea conditions of these standard operating routes by counting the operating time spent within each relevant sea area, as classified by GWS of the BWT. In most cases, fatigue strength assessments in the classification societies’ rules are performed by diverting the design loads based on North Atlantic wave environment to obtain a long-term distribution of stress range. It is, however, not clear how to define the design loads to obtain such a long-term distribution corresponding to standard operating routes. The authors have, therefore, discussed appropriate design loads for the standard operating routes by adopting spectral fatigue analysis using the derived wave scatter tables and RAO of stress of a sample ship.
