Analysis Of Sediment Deposition And Scouring Of The River Reach In Chongqing City

After the completion of Three Gorges Project ,the reservoir's operation will follow its 175-145-155m scheme. The river reach in Chongqing downtown lies in the fluctuating backwater region , after running on the 175m scheme of the Three Georges Reservoir, the process of sediment deposition and scouring condition becomes more complex. Chongqing is an important water and land transportation hub in the southwestern region of China. There distributes a lot of ports and terminals along river reach in Chongqing downtown. The sediment deposition and scouring condition of the river reach in Chongqing downtown after running on the 175m scheme of the Three Georges Reservoir is one of the important constraints of the Three Georges dam's Water level regulation. In view of its importance, many domestic experts and scholars have done a series of analysis and research on it. This paper will focus on the Analysis of Jiulongpo's sediment deposition and scouring condition Separately, by the method of observation prototype data,mathematical model , physical model and other methods.There distributes some container terminals in Jiulongpo reach.So sediment deposition of this reach will be directly related to the cargo capacity of Chongqing reach. That makes Jiulongpo reach pays a very important role in Chongqing reach,and we should take more attention to its sediment deposition.In order to analysis of sediment scouring of Jiulongpo reach, this article between the sedimentation amount and annual sediment load ,annual runoff,sediment size and the inflow rate from Jialing River is obtained.Finally,the expression to calculate the sedimentation in Jiulongpo reach is given.uses the sediment transport capacity factor U3 / h as a diagnostic parameter to juge if the river has the capacity of scouring. And this parameter can be used in the natural condition as well as in the condition that the Three Gorges reservoir is running on its 175-145-155m scheme. In the analysis of Jiulongpo reach's sediment doposition ,based on feild measurd data and physical model test data,the authors analyze the main factors affecting the sedimentation in Chongqing Jiulongpo reach of Yangtze River.The quantitative relation between the sedimentation amount and annual sediment load,annual runoff,sediment size and the inflow rate from Jialing River is obtain.Finally, the expression to calculate the sedimentation in Jiulongpo reach is given.Comprehensive analysis of the river reach in Chongqing downtown's, especially Jiulongpo's sediment deposition and scouring condition in the natural condition or after running on the 175m scheme of the Three Georges Reservoir is very helpful to Three Gorges reservoir's scheme and the waterway maintenance.