黄河下游河道断面宽深比对输沙能力的影响

根据1950~2000年黄河下游河道各站汛期实测径流量、输沙量资料,分析了花园口~高村、艾山~利津河段处于冲淤平衡状态时径流量与输沙量之间的关系,得到了冲淤平衡时,在径流量一定的情况下,河槽断面宽深比越小,输送的泥沙量越大的结论;通过概化河工模型试验,分析了在不同的主槽宽度、深度、流量和进口含沙量情况下,临界含沙量与主槽断面宽深比的关系,表明临界含沙量随流量的增大而增大,随断面宽深比的减小而增大,临界含沙量随断面宽深比减小而增大的速率随断面宽深比的减小而增大;分析了断面宽深比对黄河下游河道泥沙输移公式的影响;最后,与小浪底调水调沙实测成果进行了比较,结果表明其与笔者研究结论基本一致.

Effect of ratio of width to depth of river channel on sediment transport capacity in Lower Yellow River

According to the field data of sediment and water volume in flood period from 1950 to 2000 in the Lower Yellow River, the relation between the runoff and sediment transport volume under the silt-stable state from Huayuankou to Gaocun and from Anshan to Lijin reaches are analyzed. It is indicated that the sediment transport capacity increases with the decreasing of the ratio of width to depth of river channel under the silt-stable state.Through the river model test, the relation between the critical sediment concentration and the ratio of width to depth of river channel under different widths, depths, discharges and sediment concentrations conditions is ana lyzed. The experiment shows that the critical sediment concentration increases with the rising of discharge, with the decrease of the ratio of width to depth of river channel. Furthermore, the effect of section form on the sediment transport formula is analyzed. Finally, the test results are compared with the results of the Xiaolangdi water and sediment regulation; it is shown that they are consistent.