特小流域暴雨洪水分析方法

Storm flood calculation in minibasin

在推求特小流域洪峰流量时所建立的洪峰流量与流域面积的单相关关系存在数据点分散、相关系数小等不足。为此,建立了洪峰流量与流域面积、河道长、河道比降的复相关关系,数据点分布密集,呈窄带状、直线型。利用直线型分布特性,拟合复相关关系方程,按小值端外延计算特小流域洪峰流量。与单相关关系相比,复相关系数由0.88提高到0.98,相关数据点分布于相关线的10%上、下限偏离线之间的比例由20%提高到80%。复相关关系法理论依据充分、考虑因素全面、成果可靠程度高,不失为一种推求特小流域洪水的合理、有效方法。

For minibasin,in the establishment of single correlation between peak discharge and drainage area to calculate flood peak,some problems including scattered data,small correlation coefficient and so on are existed. For this reason,we established multiple correlations between flood peak and drainage area,watercourse length and channel gradient,and discovered that in the hydrograph,the data is distributed linearly in concentrated and narrow-banded ways. With the linear characteristic,we can fit the data and obtain the multiple correlation equation and by extending from the spectrum end of small value,we can calculate the peak discharge in minibasin. Compared with single correlation,the multiple correlation coefficient is improved from 0. 88 to0. 98,the data proportion inside the enveloping line deviated 10% from correlation line is upgraded from 20% to 80%. The results show that the multiple correlation theory is characterized with sufficient theoretical basis,comprehensive consideration and reliable results,so it is a reasonable and effective way to calculate storm flood in minibasin.