Study On Navigation Conditions Of The Port Area Of The Dam Turning Transfer Terminal In Xiluodu Fluctuating Backwater Area

Due to the narrow river channel,some hubs in southwest mountainous areas of China have not built corresponding navigation structures simultaneously,resulting in the interruption of upstream and downstream water transportation.It is an important way to solve this problem to build a dam turning transfer terminal(referred to as "dam turning terminal")and transfer goods on land through dam turning highway and port connecting road,so as to realize the connection of upstream and downstream transportation of the hub.Due to its close distance to the dam site of the project,the overturning wharf is often in the fluctuating backwater area of the downstream project.Baishitan wharf,as a dam turning Wharf in the fluctuating backwater area of Xiluodu junction downstream,has the universal nature of dam turning wharf.It is of great significance for the construction of baishitan wharf and other dam turning wharf to analyze its navigation conditions and further optimize the wharf design and operation mode.On the basis of summarizing previous studies on navigation conditions in fluctuating backwater area,this paper makes prototype observation on baishitan wharf,establishes one-dimensional and two-dimensional hydrodynamic mathematical models,and carries out research on flow conditions and sediment scouring and silting trend of baishitan wharf by classifying large amplitude water level(1)The water level in front of the Xiluodu dam has a linear relationship with the upper limit of the navigable flow of the river section in the port area.With the increase of the water level in front of the dam,the navigable flow conditions at the front of the wharf have improved significantly,and the maximum navigable flow has increased significantly.(2)When the water level in front of the Xiluodu Dam is 550 m and 560 m,the ship berthing and dock loading and unloading operations should be stopped at all incoming flows.When the water level in front of the Xiluodu Dam is 570m～600m,the water depth and width of the water surface at the front of the wharf are sufficient.Ship berthing and dock loading and unloading operations can be carried out under the condition that the flow velocity is not greater than 3m/s.(3)The results of mathematical model calculation show that after the wharf is completed and put into use,the river reach is mainly characterized by siltation.At the end of 5,10 and 15 years,the deposition rate of the reach gradually decreased,most of the deposition was concentrated in the first 5 years,and the erosion and deposition situation of the reach basically stabilized in the last 15 years.(4)The results of scouring and silting show that the front water area of the secondary loading and unloading platform has obvious siltation,which needs regular dredging,otherwise it can not meet the design water depth requirements;the front water area of the primary loading and unloading platform has small siltation thickness,which can still reach the design water depth after years of scouring and silting balance,so there is no need to carry out dredging work.