2024 Volume 80 Issue 16 Article ID: 23-16047
It has been pointed out that overtopping is the main cause of the recent years high number of levee failures. The Ministry of Land, Infrastructure, Transport and Tourism (MLIT) has launched the Technical Study Group on Strengthening River Levees with the aim of developing " Persistent River Levees " against water overtopping, and is promoting technological development of construction methods that can be used in sections where persistent river levees are to be built. In this study, a model of a block used in actual river construction was used to measure the hydrodynamic forces exerted by overflowing water, using the shape of its surface protrusions and other parameters. As a result, it was confirmed that when the height of the protrusions on the block surface is increased, the area of drag force action increases, but the drag force decreases because the flow velocity is reduced. The results indicate that constructing open holes in the block reduce the lift force. An example of a highly stable covered block shape for use on the back slope of a river levee s is shown in this study.
