Author(s): Xin Wang; Dong-yue Qian; Jun-tao Li
Linked Author(s): Xin Wang
Keywords: Ship lock approach; Sedimentation; Bed load; Separation of water and sand; Diversion and sediment retention structures
Abstract: The sedimentation of sediment in the entrance area of the ship lock approach channel is a common problem due to special boundary conditions. However, under the dual external environmental effects of stepwise interception of cascade hubs, sharp reduction of sediment content in the discharged water flow, and continuous expansion and upgrading of shipping hubs, this problem has become even more serious, directly affecting the safe and efficient operation of ship locks. Traditional submerged downstream dam engineering can no longer effectively reduce sedimentation. This study selected multiple typical sandy river locks for physical model experiments, analyzed the characteristics of riverbed erosion and sedimentation near the dam section of the hub, clarified the sedimentation mechanism in the entrance area of the approach channel, and proposed corresponding measures to reduce sedimentation. The research results indicate that under the action of unsaturated sediment discharge flow, the sediment in the near dam section starts to move on a large scale and invades the lock gate area along the water flow, becoming the main source of bed load deposition. Thus, the principle of "separation of water and sand" was proposed. The three-dimensional control and guidance of water and sand conditions was proved to be an effective technical to alleviate sedimentation in the downstream navigation channel entrance area of ship locks. Propose targeted diversion and sediment retention structures that can simultaneously achieve the purpose of intercepting the initial sediment transport belt, regulating the near bottom flow field, and guiding the sediment transport belt away from the entrance area. The experiment has proven that the above principles and measures for reducing sedimentation are effective engineering measures to prevent the sedimentation of bed load sediment in the entrance area of ship locks, and have good adaptability for the expansion and construction of ship locks.
Year: 2024