黄河宁夏段河床质对河势变化的影响

Bed Material Impact to the Potential Change in Ningxia Reach of the Yellow River

在黄河宁夏段不同断面床沙观测试验的基础上,分析了该河段床沙特性,计算了该河段泥沙起动流速。通过起动流速计算成果分析了部分河段河势变化,结果表明：青铜峡—石嘴山河段右岸的平均粒径及粗沙占全沙的比例均大于左岸的,右岸的河床边界条件相对于左岸更稳定。各取样断面不同深度的泥沙平均粒径的起动流速为0.33~0.59 m/s,滩地流速为0.24~0.49 m/s,主槽起动流速为0.52~0.59 m/s,主槽流速为2.10~2.86 m/s。结合历年河势变化分析的结果与计算分析的结论基本一致。

Through observation experiments on the basis of different bed material over the Yellow River in Ningxia, it analyzed the bed sediment characteristics of the river and calculated the variations of river regime of some sections through the calculation achievements of starting velocity. The outcomes show that the proportion of average particle size and coarse sand over the total sand of the right bank is greater than that of the left bank, the right bank in the river boundary conditions is more stable to the left. The starting velocity of sediment sampling an average particle size of each section of different depths is 0.33-0.59 m /s , floodplain flow rate is 0.24-0.49 m /s , the main channel starting velocity is 0.52-0.59 m/s and the main channel flow rate is 2.10-2.86 m/ s. River Regime combined with each year analysis of the same to results of the conclusions.