以日本中城湾观测站实测台风过程出现的最大波高序列为例,提出了泊松.最大熵复合极值分布,并将其用于计算台风海浪的重现值波高。采用年极值法与过阈法对台风波高进行长期统计分析。计算结果表明:观测时段相同,闽值的选取对重现值的估计影响不大。而阈值相同,抽样时段的长度对重现值估计的影响较大;若样本时段较短,但极值波高的最大值包含于其中,则估计得到的重现值偏大,该结果对于结构设计是偏安全的。
Taking maximum typhoon wave height series observed at Nakagusukuwan Observation Station in Japan, Poisson-maximum entropy distribution is presented to calculate typhoon wave height return values. In this paper, both annual maximum method and Peak Over Threshold (POT) are adopted for long term wave height analysis. Calculation results by POT show that the choice of threshold slightly affects the return values of wave height under the same long statistical series. The length of statistical series greatly influences the return values of wave heights under the same sampling threshold. For a relatively short sample by the POT, the estimated return parameter is safe for structure design under the condition that the maximum typhoon wave height is including in the statistical sample.