冲刷条件下熊城河段河床演变规律及趋势

Evolution law and trend of river bed in Xiongjiazhou to Chenglingji reach under erosion condition

随着三峡工程的蓄水运用及其上游向家坝、溪洛渡水库的陆续运用,水库下游河段来沙量大幅减少,清水冲刷严重,河道演变特性发生明显变化,对防洪、航运、岸线利用等方面产生影响。通过分析原型资料,研究冲刷条件下长江荆江熊城(即熊家洲—城陵矶)河段的水沙运动特性与河床演变规律,并在此基础上结合实体模型试验预测三峡水库运用30年后熊城河段的冲淤量、冲淤分布及河势变化。结果表明,熊城河段将持续保持冲刷态势,深槽不断刷深、展宽,不利于航道稳定。

With the impoundment operation of the Three Gorges Project and the successive application of Xiangjiaba and Xiluodu reservoirs in its upstream,the sediment inflow in the downstream reaches of the reservoir is greatly reduced,the scouring of clear water is serious,and the evolution characteristics of the river channel are significantly changed.The situation has an impact on flood control,navigation and the utilization of the shoreline.Based on the analysis of prototype data,we study the characteristics of water and sediment movement and riverbed evolution in Xiong-Cheng reach(Xiongjiazhou to Chenglingji)of Jingjiang River under the condition of scouring sand.On this basis,we predict the scouring and silting volume,scouring and silting distribution and river regime change of Xiong-Cheng reach after 30 years of operation of the Three Gorges Project by combining with solid model tests.The results show that the Xiong-Cheng reach will continue to scour in the future,and the deep trough will continue to deepen and widen,which is not conducive to the stability of the channel.