Kana NAKATANI, Daiki IMOTO, Yoshifumi SATOFUKA and Takahisa MIZUYAMA
Abstract
In2004, Mizuyama proposed the shutter sabo dam, which is a sabo dam with a
shutter that can be opened under control. Such a dam has the advantages of both
closed and open sabo dams. Recently, shutter sabo dams have been constructed
on some rivers. In this study, we simulated a shutter sabo dam in the Ashiarai]dani
basin using the KANAKO simulator equipped with a graphical user interface. We
compared the effectiveness of the shutter sabo dam according to differences
in when the shutter was closed. We also compared situations with and without
a movable riverbed. Comparing the sediment discharge downstream from the sabo
dam and the riverbed deformation upstream from the sabo dam, earlier closing
of the shutter was more effective at sediment control. However, when there is
a movable riverbed, earlier closing causes more riverbed degradation downstream
from the sabo dam. Therefore, to operate shutter sabo dams properly, it is necessary
to obtain detailed information on the water]discharge rates, water levels, sediment]transport
rates, and riverbed material.
Key wordsFshutter sabo dam, numerical simulation, Ashiarai]dani basin, Kanako,
sediment control