黄河利用洪水排沙不必刻意拦粗排细

简要总结我国在黄河泥沙输移方面的研究成果,根据笔者多年的研究,得出如下结论:可以利用高含沙洪水输沙入海,适宜输送的不是低含沙量的水流,而是含沙量大于200 kg/m3的高含沙水流。黄河下游洪水期窄深河道多来多排的输沙特性是造成河道多来多排的机理,在低含沙水流时水流的流速达到1.8~2 m/s,床面进入高输沙动平整状态。不仅全沙如此,造床质泥沙(d>0.025 mm的粗泥沙)也存在着同样的输沙规律。小浪底水库的泥沙多年调节,充分利用下游河道的洪水输沙潜力输沙入海,是解决黄河下游泥沙问题和节省输沙用水的有效技术途径。平水年、枯水年小浪底水库不排沙,全部水量用于兴利和环境用水,利用洪水排沙不必刻意拦粗排细。

Sediment discharge by floods of Yellow River without stressing on blocking coarse particles and releasing fine particles

The results of research on sediment transport in the Yellow River in China were briefly described.It is concluded that floods with a sediment concentration of higher than 200 kg/m3 are suitable for sediment discharge,and that the characteristics of sediment transport in narrow and deep channels of the lower Yellow River result in a mechanism of "the more sediment input, the more sediment output".When flow velocity in a river with low sediment concentration reaches 1.8-2.0 m/s,the river bed surface will be in a dynamic adjusting status,and coarse particles(d>0.025 mm) will follow the same rule.Sediment regulation in Xiaolangdi Reservoir is making full use of the flood potential in the lower river channel for sediment discharge into the lower Yellow River.In normal flow years and dry years,the total volume of flood water is used for water conservancy and environmental protection,while in wet years,floods with high sediment concentration can be used for sediment discharge.It is also unnecessary to block coarse particles and release fine particles in sediment discharge.