Mitigation Effect of Levee Breach Flow at the Chiyoda Experimental Channel

Abstract

Tomonori SHIMADA, Daisuke TOBITA, Syunichi MAEDA, Kazuhisa KASHIWAYA and Hideaki YOKOHAMA 1 正会員 土木研究所寒地土木研究所寒地河川チーム(〒062-7602 北海道札幌市豊平区平岸1条3丁目)2 正会員 国土交通省北海道開発局帯広河川事務所(〒089-0536 北海道中川郡幕別町札内西町73-6)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 Channel on the Tokachi River. The scale of the channel 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 10 and 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.