Abstract:The Xinyi River is an artificial flood discharge channel in the lower reaches of the Yi-Shu-Si River system,designed to handle flood from Luoma Lake.It is regulated by the Zhangshan Gate,and the flood is characterized by rapid rise,high discharge,and prolonged durations.The Sulian Channel is planned Class II and crosses the Xinyi River over a long distance after exiting the Chaiyi River in Shuyang County.The traversal section exists numerous troughs and shoals,tributaries converge and numerous facilities.The flood discharge of Xinyi River forms strong cross-currents,severely restricting navigation duration and safety of the Sulian Channel.Under the current conditions,it is difficult to navigate at the design-required flow corresponding to the 20-year return period water level.Reducing the maximum navigable discharge and implementing channel regulation measures can improve navigational flow conditions.Based on large-scale topographic surveys and on-site hydrological measurements during flood periods,a mathematical model of water flow in the intersection area is established.By analyzing the daily average flow with guarantee rate and river boundary conditions,it is recommended to use the 99% guarantee flow rate at the Shuyang Hydrological Station as the maximum navigable discharge.Through mathematical model calculations,corresponding channel regulation plans are proposed.The research can provide a basis for engineering design and operation,as well as reference for similar projects.
