小浪底水库运用以来黄河下游洪水演进特性

Characteristics of Flood Routing of the Lower Yellow River since the Operation of Xiaolangdi Reservoir

在分析现行河道冲淤变化及河道断面形态的基础上,结合近期实体模型试验结果,探讨了黄河下游洪水演进的变化特点。结果表明:与调水调沙前相比,黄河下游河道整体过流能力增大,其中花园口—高村河段过洪能力增长明显,高村—孙口河段过洪能力增幅较小;洪水传播时间整体缩短,高村—孙口河段漫滩洪水传播时间所占比重相对其他河段偏大;同流量水位整体下降,高村、孙口水位下降较少,因此洪水在快速向下游演进的同时洪峰沿程衰减较小,涌向下游的水量将明显增加,平滩流量较小的高村以下河段滩区灾情会进一步加重。

The paper discusses the variation characteristics of flood routing of the lower Yellow River based on the analysis of scour and fill variation of the existing channel and cross-section morphology and combining with the results of recent physical model test.The outcomes show that a) comparing with the condition before the regulated discharge regime,the overall flowing capacity of the lower channel increases,of which,the flowing capacity of Huayuankou-Gaocun Section increases remarkably and Gaocun-Sunkou Section relatively less;b) the flood travel time totally shortens,the proportion of flooding travel time of Gaocun-Sunkou Section is greater than that of other sections;c)the water level with same discharge decreases as a whole but that at Gaocun and Sunkou is relatively less,thus,the attenuation of flood peak along the flood routing is getting smaller,the water volume flowing to the downstream increases notably and the disaster situation of floodplain on the section downstream Gaocun where the bankfull discharge is smaller will be further worse during fast flood routing towards the downstream.