ID 110979
Title Alternative
NUMERICAL ANALYSIS ON NEW DIKE BACK SLOPE SHAPE TO REDUCE SCOURING AT THE LANDWARD TOW CAUSED BY THE TSUNAMI OVERFLOW
Author
Ishikawa, Masanori
Okubo, Yosuke
Keywords
coastal dike
streamline
tsunami overflow
robustness
numerical analysis
Content Type
Journal Article
Description
 2011年3月11日の東日本大震災において,海岸堤防は大きく被災し,その原因は堤防の裏法尻の洗掘を始めとする裏法側での破壊であることが多く指摘されている.著者らは,津波に対する堤防の粘り強さを検討する上で,越流した際はできる限りスムーズに陸側へ流すことが有効であると考えた.そこで,数値波動水槽(CADMAS-SURF/3D)を用いた数値解析により,作用する津波高を変化させ,構造諸元の違いによる裏法面への津波作用外力の違いを明らかにし,堤防の「粘り強さ」の発生メカニズムと設計上の留意点について考察した.
 その結果,海岸堤防裏法尻部の洗掘抑制には,裏法面の緩勾配化の他,裏法肩及び法尻部に曲線形を用い法尻陸側に落堀を採用することが有効であることを確認した.
Description Alternative
Most of coastal structures, especially coastal dikes were destroyed by the 2011 Tohoku Tsunami. It was reported that one of the most important causes was the failure of back slope of dikes due to scouring.
 It was effective to drain into the landside as possible smoothly in examining the robustness of the dike for the tsunami. In this study, a numerical model using CADMAS-SURF/3D has been applied to clarify the difference of tsunami external force toward back slope of dikes due to structure specification and to make suggestions for mechanism of robustness and design of coastal dikes. As a result, in order to restrain scouring at back slope of dikes, excepting method of moderating the back slope, streamline at top of inner slope and back slope were proposed.
Journal Title
土木学会論文集B2(海岸工学)
ISSN
18838944
Publisher
公益社団法人 土木学会
Volume
72
Issue
2
Start Page
I_1141
End Page
I_1146
Published Date
2016
Rights
© 2016 公益社団法人 土木学会
EDB ID
DOI (Published Version)
URL ( Publisher's Version )
FullText File
language
jpn
TextVersion
Publisher
departments
Research Center for Management of Disaster and Environment