EFFECTS OF COASTAL FORESTS ON SCOURING BEHIND COASTAL EMBANKMENT INDUCED BY TSUNAMI OVERFLOW

Abstract

 Coastal forest in the Tohoku and Kanto districts of Japan were destroyed by the Great East Japan tsunami on 2011. However, coastal forest had some ability to reduce the damage by a tsunami even when they were broken. In this study, the effects of coastal forests on scouring behind coastal embankment induced by tsunami overflow have been investigated by the hydraulic model experiments with erodible-bed. The scouring at landward toe of embankment becomes small with arrangement of coastal forest. Moreover, considering washed-out trees is not so much influenced on scouring size.