丹江口水库历史洪水不确定性对设计成果的影响研究

Effect of Historical Flood Uncertainty on Design Floods in the Danjiangkou Reservoir

摘要: 因资料条件等原因，所考证到的历史洪水在量级和重现期方面总存在一定的误差。研究这种不确定性对设计成果的影响，对提高设计成果质量有重要的意义。以丹江口水库为实例，分别采用适线法(CF)和线型矩法(LM)估计P-III型分布参数，建立了P-III/CF，P-III/LM两种洪水频率分析模型推求设计洪水，研究探讨了历史洪水不确定性对设计成果的影响。结果表明：历史洪水量级误差和重现期误差对设计成果均有一定的影响，但量级误差对设计成果的影响比重现期误差显著得多。P-III/CF模型计算的影响要大于P-III/LM模型。

Abstract: The historical floods always have some errors in terms of the magnitude and the return period due to many complex factors. Analyzing these uncertainty effects can improve the quality of design flood esti-mation. The P-III/CF and P-III/LM frequency analysis models in which P-III distribution couples with Curve-Fitting (CF) and L-Moment (LM) parameter estimation methods are used to evaluate the uncertainty of historical floods in the Danjiangkou Reservoir. The results show that the historical flood magnitude errors have more significant influence on design floods than the return period errors. The effects of historical flood on design floods estimated by P-III/CF model are larger than those by P-III/LM model.