黄河下游宽河段漫滩洪水作用初析

通过实测资料分析,阐明黄河下游宽河道在持续萎缩的情况下漫滩洪水仍具有较强的淤滩刷槽的行洪特点,指出漫滩洪水造成的滩地淤积主要来自于滩槽水流泥沙的横向交换。通过2002年的调水调沙试验,验证了漫滩洪水可有效增加平滩流量的认识,建议在下游泥沙还没有得到有效控制的情况下允许洪水在一定范围内漫滩,这样从长远来看对防洪是有利的。

Analysis of overbank flood flowing through wide channels on lower Yellow River

Based on an analysis of field data, it is expounded that the overbank flood is of strong capacity in sediment deposition on the flood plain and scouring in the main channel under the condition of continuous shrinkage of channels on the lower Yellow River. It is also pointed out that overbank flood-induced deposition on flood plain is mainly caused by the transversal exchange of water and sand between the flood plain and the main channel. By water and sand diversion experiments performed in 2002, it is verified that the overbank flood can effectively increase the bank-flush discharge. Finally, it is suggested that, without effective control of the sediment of the lower reach, the overbank flood within a certain range is favorable for flood control from a long-term point of view.