不同设计洪水计算方法的比较

Comparison of calculation methods for design flood

通过对香溪河流域历史洪水调查,结合洪水特性与成因分析,确定了洪水洪峰、洪量及其重现期,分析了洪水洪峰、洪量的频率特点,采用流量和暴雨两种方法推求坝址设计洪水表明,由流量推求的坝址洪水介于由暴雨途径的多种方法推算的成果之间,因此,采用由流量推求的洪水成果。古洞口工程运行实践表明,用本文方法推求的设计洪水反映了香溪河流域暴雨径流特性,成果合理。

In this work,peak flow,flood volume and return period of historical floods were determined for the Xiangxi drainage through investigation of historical floods and cause analysis of flood behaviors,and the features of frequency-curves of flood peak and flood volume were examined.Both flow method and rainfall method were used for calculation of the design flood at the dam site,and the calculations show that the flow method produced an estimation within the range estimated by various rainfall methods.Therefore,the estimation by the flow method was finally adopted and recommended to the Gudongkou project.Practical operation of this project has verified that the recommended estimation well reflects the behaviors of flood runoff and storm in the Xiangxi drainage.