基于设计洪水的梯级水库防洪安全分析

Analysis on Flood Safety of Cascade Reservoirs Based on Design Flood

以金沙江中游5个梯级水库为例,首先对基于不同历史洪水排频方案的设计洪水计算成果进行对比分析;其次在不同方案的基础上,考虑流域梯级防洪标准的协调性问题,计算各水库坝前最高水位,分析采样单一水库防洪标准和梯级协调后成果,评价梯级水库防洪安全。历史洪水的选择将直接影响设计洪水成果乃至工程防洪高程,在对单一水库防洪标准进行分析的同时应重视梯级防洪标准整体协调,并开展防洪安全评价。

Taking five cascade reservoirs in the middle reaches of Jinsha River as an example, firstly, the comparisons are made to discuss whether and how to use historical flood information. Secondly, the flood control standards for a single reservoir shall be coordinated with that for cascades, and the highest flood levels are calculated, compared and analyzed for a single reservoir and cascade reservoirs. The results suggest that the determination of historical flood is very important for flood frequency analysis as well as the magnitude and return period of each sample. Attention shall be paid on the coordination of flood control standards and safety evaluation of cascade reservoirs more than just a single reservoir.