NUMERICAL SIMULATION OF DEFORMATION OF SAND BAR FORMED AT TIP OF FUTTSU CUSPATE FORELAND BY THE 2011 TSUNAMI

Akio Kobayashi, Takaaki Uda, Masumi Serizawa, Shiho Miyahara, Masatoshi Endo

Abstract


Futtsu Point is a cuspate foreland separating Tokyo Bay and the Uraga Strait. On March 11, 2011, a tsunami generated by the Great East Japan Earthquake entered Tokyo Bay with approximately 2 m height, and flowed over this sand bar, dispersing the sand and leaving an isolated protruding sand bar. This resulted in the seawall at the foot of the sand bar being exposed to waves, increasing the potential for damage. After the tsunami, this isolated sand bar was significantly deformed, a sand spit was formed by the action of wind waves, and the seawall was refilled with sand. The subsequent shoreline changes of this protruding sand bar were measured, and the three-dimensional beach changes were calculated using the BG model (a three-dimensional model for predicting beach changes based on Bagnold’s concept).

Keywords


Futtsu cuspate foreland; beach changes; sand bar; Tsunami; BG model

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References


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DOI: https://doi.org/10.9753/icce.v34.sediment.18