Journal of the Japan Society of Erosion Control Engineering, Vol.59,No.3,2006

Study on new type slit sabo dam development for reduction of slit blockade by drift woods

Masahiro KATATANI Takashi YAMADA


Abstract

In these years, they construct many sediment discharge control dam (slit sabo dams) in Hokkaido, but cases drift woods blockade slits of the dams during floods within the scope of the sabo plan are be confirmed. To reduce this troubles, we need devices to prevent drift woods from blockading slits with dams itself, and structures trapping drift woods. In this study, we devised new type dams based on the actual conditions of slits blockade by drift woods. And we estimated the function through hydraulic model tests, achieved mentioned below conclusions.
1) We can obtain the equivalent effect of sediment control of an usual slit dam, with the new type dam whose lower about fifth of slit width was doubled and other higher slit width was reduced to half.
2) We can reduce slit blockades by drift woods with the new type dam when the water level is over the top of wider slits. Because drift woods sink and flow downstream through the wider slit. We need the wider slit is over drift woods to prevent blockading slits for certain.

Key words:Slit blockade by Drift wood, Convexity]shaped slit dam, Hydraulic model test, Sediment discharge control, Drift wood discharge

Japan Society of Erosion Control Engineering
Sabo Kaikan Bekkan 3F, 2-7-5 Hirakawa-cho, Chiyoda-ku, Tokyo
Phone +81-3-3222-0747 Fax +81-3-3230-6759
http://www.jsece.or.jp/
Mail jimu@jsece.or.jp