MISC

2017年11月

High-resolution modeling of tsunami run-up flooding: a case study of flooding in Kamaishi city, Japan, induced by the 2011 Tohoku tsunami

NATURAL HAZARDS AND EARTH SYSTEM SCIENCES
  • Ryosuke Akoh
  • ,
  • Tadaharu Ishikawa
  • ,
  • Takashi Kojima
  • ,
  • Mahito Tomaru
  • ,
  • Shiro Maeno

17
11
開始ページ
1871
終了ページ
1883
記述言語
英語
掲載種別
DOI
10.5194/nhess-17-1871-2017
出版者・発行元
COPERNICUS GESELLSCHAFT MBH

Run-up processes of the 2011 Tohoku tsunami into the city of Kamaishi, Japan, were simulated numerically using 2-D shallow water equations with a new treatment of building footprints. The model imposes an internal hydraulic condition of permeable and impermeable walls at the building footprint outline on unstructured triangular meshes. Digital data of the building footprint approximated by polygons were overlaid on a 1.0m resolution terrain model. The hydraulic boundary conditions were ascertained using conventional tsunami propagation calculation from the seismic center to nearshore areas. Run-up flow calculations were conducted under the same hydraulic conditions for several cases having different building permeabilities.
Comparison of computation results with field data suggests that the case with a small amount of wall permeability gives better agreement than the case with impermeable condition. Spatial mapping of an indicator for run-up flow intensity (I-F = (hU(2))(max), where h and U respectively denote the inundation depth and flow velocity during the flood, shows fairly good correlation with the distribution of houses destroyed by flooding. As a possible mitigation measure, the influence of the buildings on the flow was assessed using a numerical experiment for solid buildings arrayed alternately in two lines along the coast. Results show that the buildings can prevent seawater from flowing straight to the city center while maintaining access to the sea.

Web of Science ® 被引用回数 : 4

リンク情報
DOI
https://doi.org/10.5194/nhess-17-1871-2017
Web of Science
https://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=JSTA_CEL&SrcApp=J_Gate_JST&DestLinkType=FullRecord&KeyUT=WOS:000414517100001&DestApp=WOS_CPL

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