黄河下游宽河道平衡河宽的一种计算方法

Calculation Method for Balanced River Width of Wide Channel of the Lower Yellow River

来沙量大、水沙搭配不合理以及游荡型河道断面宽浅是黄河下游宽河道淤积严重的主要原因。小浪底水库的建成和运用使得改变进入下游河道的水沙搭配成为现实。在列举已有关于窄深河槽"多来多排"的研究成果和实例的基础上,分析了形成"多来多排"现象的原因,认为高含沙洪水的输沙量并不是含沙量越高就越大,而是存在一个阈值,达到这一阈值即可实现"多来多排"。基于利津水文站资料,结合曼宁公式,得到了黄河下游宽河道平衡河宽的计算公式,得出黄河下游宽河道的平衡河宽为574 m,该计算结果与渭河、北洛河及黄河山东段河道实测资料相比是合理的。

Large sediment, unreasonable water and sediment matching and wide and shallow section of meandering reach are the reasons for serious sediment of wide channel in the lower reaches of the Yellow River. The completion and application of Xiaolangdi Reservoir have realized the change of matching of water and sediment entering into the lower reaches. The research results and examples about the ＂more incoming and more discharge＂ of river channel had been cited and the formation reason of ＂more incoming and more discharge＂ had been analyzed. It is not required by the transport of river with more sediment for the hydraulic condition that more sediment needs large waterpower. It is just because of the threshold value. In case of meeting the threshold value, ＂ more incoming and more discharge＂ could be realized. Based on the Lijin Hydrological Station data, combined with the manning formula, balanced river width formula for the lower Yellow River was given. After calculation, the balanced river width of wide channel in the lower reaches of the Yellow River is 574 m. Comparing to Weihe River, Beiluo River and Shandong section of the Yellow River, the calculation result is reasonable.