水库变动回水区分汊型河道河型转化研究

Study on Transforming of Braided Channel Pattern of Changing Back water Reach in Reservoir

本文以三峡水库变动回水区青岩子河段金川碛汊道为研究对象，通过概化模型试验，结合有关的泥沙模型试验资料，分析了水库变动回水区分汊型河道河型转化各阶段的冲淤演变过程、水流结构及水力要素的变化。在此基础上阐明了河型转化的规律性，提出了引起水库变动回水区大幅度悬移质累积性淤积的临界壅水水深。

This paper takes Jinchuanji braind channel of Qingyanzi reach in the Three-Gorges Projectas an object of study. Based on the sediment and flow structure experimental research in outline modeland some experimental data of sediment of the Three Gorges Project, this paper analysis the fluvial pro-ceeding and the changing both flow structure of braind channel and some hydraulic factors in proceed-ing of the transforming of braind channel of changing backwater reach in reservoir. Based on those,this paper states the reqularity of the transforming and puts forward a critical water depth that inducesa great deal of deposition of suspend sediment in the changing backwater reach in the Three Gorges reservoir.