长江荆江河段设计洪水研究

Study on Design Flood of the Jingjiang Reach in the Yangtze River

摘要: 设计洪水是防洪评价及工程建设的基础。本文立足于荆江枝城至石首河段，梳理了三峡建库后河段的设计洪水。依据三峡水库防洪调度规则，计算了枝城站在0.33%，1%，5%，10%频率下的设计洪水;在总入流控制条件下，结合区间支流分流比曲线和站点水位流量关系，依次得到相应频率下沙市站和石首站的设计洪水。研究所得到的洪水设计值偏于安全，可为荆江河段防洪和工程设计提供科学参考依据。

Abstract: Design flood is the foundation of flood control evaluation and engineering construction. The Jingjiang reach between Zhicheng and Shishou stations is selected as case study to estimate design flood after the impounding of Three Gorges Reservoir. The design flood of 0.33%, 1%, 5%, 10% frequencies at Zhicheng station is calculated under the flood dispatching rule of Three Gorges Reservoir. Through combining the interval tributary diversion ratio and stage-discharge relation, the design floods at Shashi and Shishou stations are confirmed in the same frequency under total inflow control. The design values are relatively safe and can provide scientific reference for the Jingjiang reach flood control and engineering design.