Study On Channel Layout And Navigation Conditions In Curved River Sectionstions

With the booming development of water transportation in China,many mountainous rivers have been developed as waterways.And mountainous rivers are usually more winding,curved river flow disorder,navigation environment is complex,whether it is the construction of locks or layout of the channel,compared with straight rivers are more difficult,need for water flow conditions,route navigation,ship maneuvering,navigation conditions and other aspects of the systematic study.Therefore,it is important to carry out the research on the arrangement of navigation channel and the improvement of navigational conditions in the curved river section.In this paper,we take the sharp bend section of Jinjiang Danxia hub as the generalized model,and adopt physical model,mathematical model and ship simulation for the most unfavorable sharp bend channel type such as 90° sharp bend channel in the upstream of hub and 360° sharp bend channel in the downstream of hub,and carry out a series of problems such as difficult upstream and downstream channel layout,poor navigable current condition,difficult ship navigation in the key position such as the channel of the sharp bend section and the approach channel of the ship lock.The experimental simulation research has been carried out,and a scheme of channel and lock layout,measures to improve the navigable water flow conditions and navigation methods for ships passing through the bends and locks have been proposed for the sharply curved section of the hub.The research results of this paper can provide reference for the design planning,layout and construction of similar curved river channel and the navigation method of ship crossing.The research results of this paper are as follows:(1)studied the upstream of the hub curved connecting channel layout scheme,proposed to optimize the river conditions in the curved river section and optimize the channel ship adjustment water area and other improvement measures to solve the problem that the ship is controlled by the sharp bend river potential difficult to enter the upper approach channel of the lock.(2)Study the influence factors of water flow conditions in the downstream bending channel of the hub,analyze the influence of the hub flooding and bending water sweeping on the ship entering and leaving the lock,summarize the water flow characteristics of the bending river section in the combination of dynamic and static water,study and put forward the optimization plan to improve the navigation conditions: the hub floodgate should follow the river potential and open the gate hole far from the channel as a priority;strengthen the water diffusion and smooth the water flow direction to Reduce the disturbance in the dynamic and static water intersection area of the approach channel.(3)The navigation conditions of the sharp bend and narrow river channel downstream of the hub are studied,and its bend sweep characteristics are analyzed,and remediation measures are proposed: the entrance of the sharp bend is narrow and the water depth is shallow,and the local widening can significantly reduce the flow velocity at the entry bend and increase the maneuvering water range when the ship goes upstream;the bend sweep at the exit of the sharp bend is obvious,and the widening of the convex bank can reduce the sweep flow velocity.The general law of water movement and the difficulties of ship navigation are analyzed,and the optimized engineering measures for river dredging and channel optimization are proposed.(4)For the channel arranged in the curved section of the river,after clarifying its river characteristics and water flow conditions,the route planning study was carried out for the passage of ships through the curved gate to improve the safety of ship navigation.