Continuous Random Wave Loading on Structural Members

This paper considers first the short-term probabilistic description of random wave loading on offshore structures composed of members for which the Morison form of load mechanism is appropriate. Special consideration is given to dealing with the inherent non-linearity of the drag forces. The general multivariate distribution of loading is derived from the linear Gaussian model of long-crested random seas. The application of the multivariate distribution to yield the probabilistic description of structural response variables is indicated. Probability distributions of peak loads are developed
which show the general wideband behaviour contrasted with the simpler distribution which results from appropriate narrow band assumptions. Comparisons of the theoretical models are made with prototype recordings from an offshore platform and laboratory scale experiments. Comments are made on various aspects of the numerical computations necessary in the application of the theoretical models proposed.

R.G. Tickell