Study On Riverbed Evolvement And Regulation Parameters In Jiangjin-Chongqing Reach Of The Three Gorges Project Backwater Tail

Ministry of communications organized the water way construction of Jiangjin-Chongqing in Upper Yangtze River to meet the need of shipping enterprises and combine With the port construction of Lanjiatuo70’s in the20th Century. There ara13regulating structures have built in Yanziqi, Kuzhuqi, Xiaonanhai, Zhajiao, Zhuanzaozi shoal and rapide. The river reach main urban area of Chongqing only takes maintenance gredging for The complex peripheral environment. After the2008flood period, the Three Gorges Project begin to the175m test store water. with the change of Flow and sediment transport, the Evolution rules, Channel condition and Regulation effect have changed too. So, it is very necessary to analyse the adaptability of regulation parameters under new water-sediment condition.In this paper, we take5shoal and rapide in Jiangjin to Chongqing reach in the upper Yangtze River as the research objects. We analysis the level and water-sediment variation, scouring and silting evolution of each shoal and analysis regulation effect of the regulation works Have been built and research the Riverbed evolution and the Channel condition variety, To raise the regulation parameters in the future.The conclusions are as follows:(1) After the Three Gorges Project storing water, the water level vary widely of the backwater area. The backwater area tail keeps rising and the water level tend to smooth because of the the dam front water level rising. The Incoming Water and Sediment and Riverbed evolution change a lot, for the same change in controllable Zhutuo And Cuntan hydrologic station.(2) After the Three Gorges Project storing water, sediment movement take place in some recirculation regions, subcritical flow regions and Inlet river. some reachs regulation works Have been built arise river bed silting-up. the regulation effect of regulating structures began to lessen. It will take some side effects for shipping.(3) In this paper, the basic regulation parameters such as Design Lowest Navigable Stage, ascending rapid hydraulic parameters, Regulation Stage and regulation width were researched. In order to provide reference for engineering practice in the future.