Research on Regulation Thoughts for Shoal at Confluence of Xinzhou Channel in the Middle Reach of the Yangtze River

摘要

This paper conducts in-depth discussion to influence factor of shoal's refloating change through analysis. According to analysis, run of upper trench in the Xinzhou south channel and change of north channel's inflow is the major cause of confluence refloating; the article also discusses and illustrates relative thoughts issues in the process of regulating shoal at confluence. Braided reaches prevail in the middle and the lower reaches of the Yangtze River, while navigation obstruction issue at confluence reach is also quite common and complicated. Navigation obstruction refloating of confluence reach is often due to it is jacked by outflow of one branch when water level is high, which forces flow velocity at the other branch of channel slow down. Plus inflow change at both branch channels, sediment deposition and can easily form shoal at confluence of the end of Xinzhou; confluence shoal evolution has much to do with condition adjustment of incoming water and sediment in the upstream besides it is determined by its own pattern. Shoal channel regulation issue at confluence reach is no less complex than estuary reach. It is extremely complicated, therefore, there is an urgent need and it is also imperative to strengthen regulation research on this kind of shoals so as to enhance technological level of regulation.