摘要: |
重现期波高是港口海岸及海洋工程设计中不可回避的一个重要设计参数,尤其对深水海港、海上平台、海底油气管道、沿海核电站等重大涉海工程设计具有巨大的经济价值和深远的社会效益。但是,现有重现期波高推算缺乏统一的计算方法,导致计算结果相差悬殊。研究重现期波高的统一化计算方法,分析重现期波高计算中存在的各种不确定因素,提出减少这些不确定因素的新方法,建立误差小、应用方便、方法统一的重现期波高计算方法。基于澳大利亚悉尼站的长期连续观测波浪数据,研究发现:广义帕累托函数(generalized Pareto distribution III,GPD-III)和威布尔(Weibull)是重现期波高计算的最佳候选极值分布函数,新推导的函数形状参数计算公式较好提高重现期波高的计算精度,极值波高数据的分析方法和样本大小是影响重现期波高计算精确度的两个重要因素,短期波浪资料和年极值法可能高估重现期波高值。逐个风暴的极值波高数据分析法及最佳候选极值分布函数GPD-III和Weibull建议应用于涉海工程设计的重现期波高推算。 |
关键词: 重现期 重现期波高 极值分析 广义极值函数 广义帕累托函数 |
DOI:10.11693/hyhz20220300051 |
分类号:TV139.2 |
基金项目:NSFC-山东联合重点基金,U1806227号。 |
附件 |
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UNIFIED APPROACH FOR ESTIMATION OF RETURN OCEAN WAVE HEIGHT |
YOU Zai-Jin
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Centre for Ports and Maritime Safety, Dalian Maritime University, Dalian 116085, China
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Abstract: |
Return wave height is an important parameter in the design of coastal and ocean engineering. Accurate calculation of design or return wave height is of enormous economic value and social value especially for deep-water harbors, ocean platforms, subsea gas and oil pipelines, and coastal nuclear power stations. However, there is no unique approach for calculation of return wave height, and results from different methods are significantly different. The present study is undertaken to analyze uncertainty in extrapolation of return wave height, minimize errors, and develop a unified methodology for calculation of return wave height. Based on long-term wave data continuously collected at Sydney permanent wave station on the coast of New South Wales in Australia, it is found that GPD-III and Weibull are the most suitable candidate distribution functions for extrapolation of return wave heights, newly derived formulation Eq.(8) will enable us to accurately estimate the shape parameters of the two distribution functions. The sample size and analysis method of extreme wave data are two important factors affecting the accuracy of return wave height extrapolated. Short wave records and the use of annual maximum method for analysis of extreme wave data could underestimate the return wave heights. The storm-by-storm method for analysis of extreme wave data and GPD-III or Weibull for extrapolation of return wave heights are highly recommended for coastal and ocean engineering design purposes. |
Key words: return period return wave height extreme value analysis GEV (generalized extreme value) GPD (generalized Pareto distribution) |