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In accordance with "The Waterway Development Plan On The Trunk Line Of The Yangtze River", Shuifu to Yibin reach of Changjiang river isⅢGrade channel standard and open to navigation the 1000t level barge fleet. Daxuetan shoals consists of Qishoutan, Daxuetan, Laocaibatan and Xiaoxuetan, has such as the shallow, curved, rapid and dangerous navigation-obstructing characteristics, which plays a critical role in controlling the conditions of Shuifu to Yibin reach. Through theoretical analysis and river model tests, analyzed the sediment conditions, evolution of river bed and navigation obstruction characteristic of the Daxuetan shoals, studied more than 10 group regulation schemes of the old and new channel, achieved the following key research results:Daxuetan shoals close to the confluence of Jinsha River and Minjiang River, water and sediment conditions is very complicated. Through a number of detailed statistical analysis of real measured data, presented over the frequency curve of the Jinsha River confluence, statistics of the convergence ratio of the most likely to occur, recommended the appropriate afflux ratio for beach research, and gave the relationship between the control of water ruler of a single beach and the two rivers flow.Daxuetan shoals’1:100 normal river model of navigation-obstruction characteristic analysis and regulation scheme research. Model uses the flow measurement and control system, the water level measurement system, the tailwater control system, as well as a wide range of synchronous velocimetry system and other advanced equipment. Compared with the model’s water level, velocity distribution, buoys’flow direction and buoys, the results closely meet the actual situation and similarity requirements of river model.Based on the principles of hydraulics and river mechanics and the data of actual measurement and text, the causes were analyzed in detail of every shoal. Qishoutan is steep-bed, shallow, rapid and low-water cobble stone shoal, Daxuetan is sharp and dangerous shoal, Laocaibatan is narrow reach, steep-bed, rapid and low-water cobble stone shoal, and Xiaoxuetan is mainly rapid and flood bedrock shoal.By the comprehensive theory analysis and the river model, regulation scheme of Daxuetan shoals was recommended. Optimization schemeⅠ-6 has certain advantages in the volume, visual navigation, river regime change and the priorities level of flow along the reach, which is the recommended scheme. Optimization SchemeⅡalso has a certain advantage in the regulation effect and the smooth channel of Qishoutan, which is the selection scheme.
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