历史特大洪水对设计洪水频率曲线参数及设计值的影响

本文运用统计试验方法，研究了实测洪水系列中加入４种不同情况的历史特大洪水（简称历史洪水，下同）对洪水频率曲线及设计值的影响。结果表明：加入的历史洪水重现期越长，则设计洪水成果的稳定性越好，精度越高；在同一历史洪水考证期内，加入１～２个历史洪水对提高设计洪水成果的稳定性和精度作用很明显，加入更多的历史洪水则作用不大；尽管历史洪水重现期有一定误差，但仍能有效地提高设计洪水成果的稳定性；历史洪水值的误差对设计洪水的影响比历史洪水重现期误差对设计洪水的影响大得多。

The Effect of Historical Flood Events on Design Floo

The effects of historical extraordinary flood events added to observed flood series, four cases mentioned in this paper, have been studied by using statistical method. The major results are as follows:The longer return period of the extraordinary flood events added is, the more stable and more accurate the design flood will be. In certain research span, the effects of improving the precision or stability of design flood are quite visible when the observed flood series is added in with one or two extraordinary flood events, but when more than two extraordinary flood events are added in, the precision or stability almost cann't be further improved. Even there are errors on the estimation of the return period of extraordinary flood events, the stability of the design flood can also be improved when they are added in. Effect of extraordinary event value errors on precision of design flood are more visible than their period errors.