Extreme Waves and Ship Design

Recent research has demonstrated that extreme waves, waves with crest to trough heights of 20 to 30 meters, occur more frequently than previously thought. Also, over the past several decades, a surprising number of large commercial vessels have been lost in incidents involving extreme waves. Many of the victims were bulk carriers. Current design criteria generally consider significant wave heights less than 11 meters (36 feet). Based on what is known today, this criterion is inadequate and consideration should be given to designing for significant wave heights of 20 meters (65 feet), meanwhile recognizing that waves 30 meters (98 feet) high are not out of the question. The dynamic force of wave impacts should also be included in the structural analysis of the vessel, hatch covers and other vulnerable areas (as opposed to relying on static or quasi-dynamic analyses).