Efficiency of Flushing through a Sluice-Gated Weir

摘要

The four major rivers restoration project (4MRRP) was carried out in Korea between Oct., 2009 and Sep., 2012. The major purposes and effects of the 4MRRP were flood control, safe water security and water quality improvement. For flood control, 450 million m3 of sediments were dredged with the reinforcement of 620 km-long old levees. Sixteen weirs were constructed and 93 reservoir banks were elevated for safe water security. Deformation of the main channels appeared to be inevitable because the longitudinal slope and cross section of the river had changed. In particular the construction of weirs could take the role of sediment detention ponds because the weirs will slow down the velocity and reduce the capability of sediment transportation. Therefore, it is crucial to determine how the siltation phenomena upstream of a weir can be fixed. This study examined the sluicing efficiency of the gate operation for the Gumi weir using 2-dimensional numerical simulations.