Probability distribution of wave run up and dynamic response on a large volume semi-submersible

Abstract

The wave run up under semi-submersible platform deck and the dynamic response are important design factors, and determine the expected minimum air gap in extreme design conditions. For a semi-submersible, the prediction of probabilities wave run up in harsh environments is a challenging task. This paper addresses the problem of expressing the probability density and cumulative distribution functions that utilize Weibull distribution to model estimates the waves run up for a large volume semi-submersible squared-section columns platform in two sea states. The two parameters Weibull distribution, namely shape parameter and scale parameter were considered. The analysis interpreted the measured data of 9 realizations with different seeds in the moored model experiments. The length of total measured data analyzed included approximately 9 times 250 waves for each sea state. The wave run up was found by model estimates using a Rayleigh distribution, and some waves run up were identical apart from one another for different seeds. Finally, by this model with a sequence return for two sea states the associated motions distribution for the large volume semi-submersible platform were numerically predicted.