考虑历史洪水的防洪计算时历法效果分析

Effect Analysis of Time Series Method in Consideration of Historical Flood on Flood Control Calculation

针对现行的防洪计算方法大多存在局限性的问题,提出了考虑历史洪水的时历法,推求了历史洪水流量过程线与历史库容重现期,分析了防洪库容序列的分布特性及防洪库容序列连续部分的线型选择,给出了适当的解决方案,并与传统防洪计算方法的统计试验进行比较。结果表明,当历史洪水流量过程线采用按峰值挑选法和按峰量值挑选法推求时,考虑历史洪水的时历法具有较好的估计精度,对防洪库容设计值的估计效果与洪水随机模拟法相当,优于设计洪水过程线法,可用于解决水库防洪计算问题。而样本容量的增长、合理考虑历史洪水信息对提高设计防洪库容估计精度均具有积极意义。

Time series method in consideration of historical flood （TSM） is introduced as a new way to solve flood control calculation problem. And this paper also provides proper solutions to technical points of TSM. These technical points are estimation of runoff process of historical flood, estimation of return period of historical flood control volume, analysis of distribution characteristics of flood control volume series, curve distribution selection of continues portion of flood control volume series. According to Monte Carlo experimental results on comparison of TSM and traditional meth- ods, one conclusion is that TSM has equivalent precision as stochastic simulation method and has higher precision than design flood hydrograph method on estimation of design flood control volume when runoff process of historical flood is estimated based on flood peak or flood volume. Another conclusion is that precision of design flood control volume will increased by a larger sample size and consideration of more reliable historical floods information reasonably.