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 analyzed.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.