感潮河段支流口门枢纽布置方法研究

跨流域调水工程中，感潮河段支流口门枢纽受到用地条件限制常距江较近且开敞布置，进出口门水流受到非对称涨落潮流牵制，引水、排涝、通航功能协调困难。以新孟河延伸拓浚工程的界牌水利枢纽为例，通过物理模型与数学模型试验相结合的方法，研究枢纽水动力条件及存在问题，并在此基础上提出枢纽总体布置方法。结果表明:枢纽外江侧口门开敞，引排水受涨落潮牵制明显，致使入江口堤头凸出挑流，泵站、节制闸进口及引航道口门区存在斜流；而枢纽内河侧边界固定，且节制闸正对引河，引航道处于遮蔽区，引排水流平顺。枢纽整体布置遵循以下原则:新开引河口门区与主河道呈锐角布置，角度取决于涨落潮历时对比，协调引水功能；引河与主河道之间堤头形态呈梯级布置，下梯级为锐角，上梯级为钝角，协调排水功能；节制闸正对引河布置，船闸布置在节制闸常态缓流区侧，泵站布置在节制闸另一侧，重点协调通航功能；枢纽尽可能远离口门区，使泵站和引航道位于岸线遮蔽区，减弱不良流态，协调枢纽各功能并使其充分发挥 。

Layout principles of hydraulic project in the branch mouth of a tidal river

In the inter-basin water transfer project, the hydraulic junction in the branch mouth of a tidal river is often located near the main river and keeps an open layout due to the restriction of land areas. The flow condition at the branch mouth is restrained by asymmetrical tidal current, which makes it difficult to coordinate the diversion, drainage and navigation functions. Taking Jiepai Hydraulic Junction of Xinmenghe Extension-Drainage Project as an example, by combining physical model with mathematical model test, we obtain the overall flow condition, reveal the formation mechanism of bad flow pattern, and put forward the overall layout principles of the junction. The results show that the flow condition at the branch mouth is significantly influenced by the fluctuation tide, which leads to the bank head protruding current and the oblique flow at the inlet of the pumping station, the sluice gate and the entrance of the lock approach channel. The boundary of the inner river is fixed, and the sluice is located in the middle of the inner river, which leads to a smooth flow condition. The overall layout of the project follows the principles: the branch and the main river are arranged at sharp angles, and the exact angle value depends on the duration of fluctuating tide to coordinate the diversion function; the bank head between the branch and the main river is arranged in a two-layer cascade shape, the lower cascade is at an acute angle, and the upper cascade is at blunt angles, to coordinate the drainage function; the sluice is arranged in the middle of the branch, the ship lock is arranged at the side always with smooth flow condition, and the pump station is arranged at the other side, to coordinate the navigation function. The junction should be constructed far away from the tidal river if possible, so that the pump station and approach channel are sheltered by the shoreline and bad flow pattern is reduced, to coordinate the whole functions. The junction should be constructed far away from the tidal river if possible, so that the pump station and approach channel are sheltered by the shoreline and the bad flow pattern is reduced, to coordinate the whole functions.