外秦淮河武定门闸上游偏流淤积成因及流态改善措施

针对南京市外秦淮河武定门闸上游偏流易淤问题,建立物理模型试验,结合实测资料和理论分析,对闸上游河道淤积成因进行了深入分析,并提出增建导流墙对闸前河道流态改善的措施。研究结果表明:受闸上游弯道影响形成偏流,闸前河道两侧产生左大右小两个明显回流区,导致左侧河床较右侧淤积明显;水闸常年运行,大部分时间闸前河道水流动力较弱,易形成缓流淤积。通过闸前设置导流墙,可以改变闸前河道流态,使左右两侧回流区范围显著减小。

Study on the causes of sediment deposition and the improvement of flow pattern in the upper part of Wudingmen Sluice in the outer Qinhuai River

In this study, combined with the measured data and theoretical analysis, the physical model experiment is setup for the Wudingmen sluice in Nanjing. After that, the problems of sediment deposition is formed and studied. The bend upstream induced by the sluice changes the flow pattern that can be improved by setting a diversion wall. The results also show that the river bend infect the flow pattern. Meanwhile, there are obvious recirculation zone on the both sides of river and the size of left zone is larger than the right, which results in the heavier deposition of left riverbed than the right side. In addition, the weak river flow dynamics makes the sediment deposition heavier. By setting the diversion wall upstream the sluice, the size of the recirculation zone is reduced and the flow pattern is improved. This study can provide reference for improving the upstream flow pattern and reducing sediment deposition.