Naval architects studying the structural dynamics of ships or other seakeeping responses have an interest in joint responses such as the concurrent six-degree-of-freedom hull girder loads. Traditional treatments of seakeeping have focused primarily on the statistics of individual responses. The following paper examines and elucidates the relationship between a variety of methods appropriate to the statistical characterization of joint responses, including phase co-factors, cross co-spectral moments and joint normal techniques. Finally, it posits a method to encompass an equivalent irregular wave, as a proposed extension of ABS’s dynamic loading approach (DLA).
Author: Bruce L. Hutchison