历史洪水调查重现期实例分析

Case Study of Historical Flood Recurrence Period

以流域水文断面历年洪峰流量为例,利用独立样本分析法对该断面洪水频率进行了分析计算,指出了该方法在实际工作中的优势。经分析计算可知,年最大洪水频率计算时是否加入历史洪水对计算结果影响较大,且重现期越长误差越大,本例中最大误差达25.7%。洪水频率计算实际中往往忽视调查历史大洪水,有时也存在对调查历史洪水的不认可现象,但经文献刊印的调查历史洪水其可信度较高,不应轻易舍弃,否则洪水频率分析结果会偏小很多,对工程设计造成不利影响。

Through taking annual peak flow of hydrological sections in the basin as an example,the study uses independent sample analysis to analyze and calculate the flood frequency of the cross section,and points out the advantages of the method in practical work.Through analysis and calculation,the addition of historical flood has greater influence on the calculation results of annual maximum flood frequency calculation.The longer the recurrence interval is,the larger the error is.The maximum error of the example is 25.7%.In the calculation of flood frequency,flood in the history is often neglected,no agreement of the investigation of historical flood appears sometimes,but the reliability of the investigation of historical flood is greater through the investigation of published literature.So it should not be simply abandoned,and the flood frequency analysis is greatly less,which will be not beneficial to engineering design.