
Calculation of design wave height and its application base on independent sample
LIU Guilin, FANG Dan, SONG Shichun, LIU Bohu
Journal of Marine Sciences ›› 2023, Vol. 41 ›› Issue (3) : 73-82.
Calculation of design wave height and its application base on independent sample
The selection of extreme value samples and the determination of distribution models are two crucial aspects when calculating the design wave height. When selecting extreme value samples using the peaks over threshold method, the standard storm length method is commonly used to “de-cluster” the exceedances in order to make the samples conform to independence standards. However, the crucial parameter in the standard storm length method needs to be manually selected which increases the uncertainty of samples. In this paper, an automatic standard storm length estimation method is proposed, then the wave height peaks over threshold sample in the western Guangdong sea area is selected based on this method. To accurately fit the sharp peak and heavy tail of the wave height peaks over threshold sample, the combined distribution method is used to construct a new model: Gumbel-Pareto distribution model. Based on this model, the design wave height calculation is carried out in the western Guangdong sea area. The result shows that the goodness of fit for the Gumbel-Pareto distribution model to the wave height peaks over threshold sample is higher than that of Gumbel distribution and Generalized Pareto distribution, which can offer a reasonable reference for the design of large offshore engineering.
independent samples / standard storm length / Gumbel-Pareto distribution / design wave height calculation
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