黄河下游游荡河段清水冲刷时期河床调整的复杂响应现象

Complex Response in Channel Adjustment in the Lower Yellow River during the Period of Clear-Water Scour

以１９６０～１９６２年三门峡水库下泄清水时期定位观测资料为基础，研究了清水冲刷条件下黄河下游河床调整过程。结果表明，由于河床边界条件的不同，游荡段的上段（铁谢－桃花峪）和下段（桃花峪－辛寨）的河床调整过程表现出明显的差异，由此可以划分两种不同的调整方式和复杂响应类型：河岸抗冲性强、河床组成物质较粗的河段，河床调整及其中的复杂响应主要与水力参数有关；河岸抗冲性弱、河床物质组成较细的河段，河床调整中的复杂响应主要与河床形态有关。研究所得结论，可为预测小浪底水库建成后黄河下游河床演变趋势提供参考。

Based on the data of the Sanmenxia Reservoir during the period of clear-water scour in 1960- 1964, the channel adjustment under the conditions of clear-water scour has been dealt with in the paper. The results indicate a marked difference in channel adjustment between the upper and lower reaches of the braided channel(the reach Tiexie to Taohuayu and the reach Taohuayu to Xinzhai). Accordingly, two types of complex response in channel adjustment have been identified: In the reach where the erosional resistance of bank material is strong and the bed material is coarse, the complex response is related with the adjustment of hydraulic parameters; and in the reach where the erosional resistance of bank material is weak and the bed material is fine, the complex response is related with the adjustment of channel morphology. These can be referred for predicting the tendency of channel change after the construction of the Xiaolangdi Reservoir.