应用超阈值抽样及Copula函数推求水库设计洪水

Application of Partial Duration Series and Copulas in Deriving Design Flood of Reservoir

按照超阈值理论对洪水资料进行抽样,应用Copula函数分别建立了超阈值洪水洪峰、3d洪量和7d洪量与其发生时间的联合分布,得到了不同量级洪水在发生时间上的概率分布图,对水库汛期防洪调度运用具有一定的指导意义。同时,应用Copula函数建立了年最大超阈值洪水洪峰、3d洪量和7d洪量的联合分布,以此得到设计标准和校核标准的设计洪水,并通过同频率放大法得到了设计洪水过程线,该洪水过程线更符合水文现象的内在规律,展现了超阈值理论和Copula函数在水文洪水频率分析计算领域的良好应用前景。

This paper sampled the data according to the theory of partial duration series,and used the Copula function to establish the joint distribution between the magnitude and occurrence time of the flood peak,the quantity of flood during 3 days and 7 days.As a result,the probability distribution of the flood occurrence time was obtained at the various magnitudes,which is useful for reservoir regulation in flood control.At the same time,Copula function was used to establish joint distribution of the annual maximum flood peak,3-day and 7-day flood quantities,so as to get floods the design standard and check standard.And then the design flood hydrograph was obtained by using the method of homogenous frequency enlargement.The flood hydrograph is better in the way of the inherent law of hydrological phenomena.It shows a nice prospect in the field of hydrological flood frequency analy-sis and calculation of the theory of partial duration series and Copula function.