For the purpose of mitigating flood damage by overflow from a levee breached, the authors conducted an
experiment using the full-scale levee at the Chiyoda Experimental Flume on the Tokachi River. The scale of the flume is 1300m long and 30m wide, accompanying a flood area of 80m width. In the experiment works, a group of blocks were installed on the slope of the levee 20 m downstream from the artificial breach, and water was let flow from upstream. After the water was let flow, when the breach progressed downstream to the concrete armor blocks, the blocks protected the failure levee. The downstream progress of breach was expected to be arrested by the concrete blocks which were expected to weaken the inundation flow from the channel. The control effects by the concrete blocks were examined. The authors concluded that placing concrete blocks on a downstream slope of levees can control levee breaches effectively. |