Abstract
At the IMO (International Maritime Organization), new generation intact stability criteria are now under development. Here it is essential to establish a physics-based method for quantifying probability of capsizing for intact ships in beam wind and waves. For this purpose, the authors herewith propose an updated methodology for calculating the capsizing probability based on piece-wise linear approximation of restoring arm curve. Although its earlier version had been reported so far, the current version was newly formulated with more rigorous theoretical modelling on roll properties at the moment of outcrossing of roll angle. For validating this new method, a Monte Carlo simulation using a time-domain model was executed with its confidence interval analyses. As a result, it was obtained reasonably good agreement between the new theoretical method and the relevant Monte Carlo simulation. It was also confirmed that the computational time of new theoretical method is much shorter than that of Monte Carlo simulation. Therefore, the new theoretical method can be recommended as a reliable and feasible element of new generation intact stability criteria.
