基于入库设计洪水不确定性的梯级水库防洪极限风险率研究与应用

发布时间：2018-06-27 21:21

  本文选题：入库洪水 + 极限风险　； 参考：《华北电力大学》2014年硕士论文

【摘要】：水资源是生命的源泉,一直是人类社会经济发展的重要保障。当今,由于降水在时间空间上的不均匀分布,年际之间的剧烈变化,使得洪涝、旱灾时常发生有限的水资源未能得到最大化的利用。梯级水库作为修建在河流上的主要工程措施,担负着整个流域的涝旱灾害防治和水资源再分配的重要职责,科学合理地进行梯级水库防洪调度,及时拦蓄洪水,可以有效缓解水资源短缺与灾害频发之间的矛盾,水库的极限风险问题则是梯级水库防洪调度中的关键和首要任务。 针对梯级水库的极限风险问题,本文基于极限风险的概念,主要考虑从水文不确定性角度分析下游水库的入库设计洪水。其洪水组成分为两部分,即上游干流来水和区间支流来水。首先,不同的洪水典型组成对梯级水库的联合防洪调度风险有着重要影响,按洪峰在洪水过程中出现的位置划分4种典型洪水,并从中各筛选出4条典型洪水过程线,组合成16种情景,分析不同形状典型入库梯级洪水对水库极限风险率的影响,并采用同倍比放大法推出梯级水库入库设计洪水,以下游水库设计洪水位作为极限风险控制指标,通过调洪演算得到防洪极限风险率。其次,融合统计学极值理论与概率分布的尾部效应,对水文中常用的概率分布类型进行分类,根据实测资料利用概率论数学模型及数理统计方法进行频率线型影响分析。黄河上游龙羊峡和刘家峡梯级水库中刘家峡水库的防洪极限风险率实例计算结果表明,典型洪水组成方面,影响刘家峡水库极限风险主要的典型来水是干流为洪峰而支流洪峰靠前的洪水组合；线型选择方面,由配线结果可知采用广义极值(GEV)分布的所得出的设计洪量要比传统P-Ⅲ型曲线的设计洪量要大,使设计防洪工程结果更偏于安全。
[Abstract]:Water resources is the source of life, has been an important guarantee of human social and economic development. Nowadays, due to the uneven distribution of precipitation in time and space and the severe changes between years, flood and drought often occur and limited water resources can not be maximized. As the main engineering measures built on rivers, cascade reservoirs are responsible for the prevention and control of waterlogging and drought disasters and the redistribution of water resources in the whole river basin. It can effectively alleviate the contradiction between the shortage of water resources and frequent disasters, and the limit risk of reservoirs is the key and the most important task in the flood control operation of cascade reservoirs. Aiming at the limit risk problem of cascade reservoirs, this paper, based on the concept of limit risk, mainly considers the design flood of downstream reservoirs from the point of view of hydrological uncertainty. The flood consists of two parts: the upstream main stream and the branch stream. First of all, different typical flood components have an important impact on the risk of combined flood control operation of cascade reservoirs. According to the location of Hong Feng in the flood process, four typical floods are divided, and four typical flood process lines are screened out. Combined into 16 scenarios, this paper analyzes the influence of typical cascade flood with different shapes on the limit risk rate of reservoir, and deduces the design flood of cascade reservoir by using the method of magnifying the same ratio. The design flood level of the following reservoir is regarded as the limit risk control index. The limit risk rate of flood control is obtained by flood control calculation. Secondly, combining the extreme value theory of statistics with the tail effect of probability distribution, the types of probability distribution commonly used in hydrology are classified. According to the measured data, frequency linear influence analysis is carried out by using probability mathematical model and mathematical statistical method. The calculation results of flood control limit risk rate of Liujiaxia Reservoir in Longyangxia and Liujiaxia Cascade reservoirs in the upper reaches of the Yellow River show that the typical flood composition, The main typical incoming water that affects the limit risk of Liujiaxia Reservoir is the flood combination in which the main stream is Hong Feng and the tributary Hong Feng is forward. From the distribution line results, the design flood volume obtained by using the generalized extreme value (GEV) distribution is larger than that of the traditional P- 鈪，

本文编号：2075314