Article

Study on Reinforcement Method of Dykes by Steel Sheet-pile against Earthquake and Tsunami Disasters

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Abstract

Expeditious seismic countermeasure for coastal infrastructures have been required since the prediction of huge earthquakes and tsunami in the near future throughout Japan. Coastal dykes built on liquefiable layers have a risk of malfunction caused by subsidence due to liquefaction and/or collapse due to overflowing (i.e. tsunami). In this paper, the robust performance of coastal dykes with sheet piles installed at the top of slopes is confirmed by applying FEM analysis. Dykes of this structure would be a reasonable and cost effective method against disasters with continuous earthquakes and tsunami. Also check points on the structural stability of coastal dykes reinforced with sheet piles are presented in this paper together with possible usage of the crown of coastal dykes in the process from the beginning of a disaster to the recovery.

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... Pile walls were installed by the Press-in Method in the levee body, so that the height of the levee is maintained even when the ground is liquefied by the significant seis mic motion expected in the coming Nankai Trough earthquake. In addition to the performance for lique faction, the structure is expected to show tenacity for tsunami loads (Furuichi et al., 2015). Varieties of other case histories related with the Press-in Method can be found in IPA (2016) and IPA (2019). ...
... Kimizu and Otani (2010) compared the reinforcement effect of the CS and PFS methods on the soft ground deformation due to embankment construction using the 3D finite element analysis. Furuichi et al (2015) and evaluated the seismic behavior of embankment with steel sheet pile based on the result of a model test and a numerical analysis. ...
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Kazutaka Otsushi; Analytical study on levees reinforced by double sheet piles with partition walls
  • Kakuta Fujiwara
  • Atsushi Yashima
  • Kazuhide Sawada
  • Yukio Abe