五十嵐川における河川構造物への流速の作用時間に着目した被災要因の分析
キーワード:
ikarashi river,
Niigata and Fukushima Heavy Rainfall 2011,
time integrated friction velocity,
iRic
2012 年 18 巻 p. 245-250
詳細
2012 年 18 巻 p. 245-250
In Ikarashi river, a risk of levee break was high at Niigata-Fukushima Heavy Rainfall Disaster in july 2011 because of occurrence of excessive flood. In order to comprehend fluid forces acting to channel, we conducted full 2-d analysis given the hydro of this excessive floods at channel has cross-section before the disaster. In this study, we discussed estimating indexes to predict disaster points due to flood flows. At a result of flow velocity and friction velocity, time integration of friction velocity has a close relationship of disaster points. Though current river channel designing method consider only velocity, the designing method should import the concept of time integrated friction velocity.
