Abstract
An earthquake with a magnitude of 9.0 occurred off the Pacific Coast of Miyagi Prefecture, Japan on March 11th, 2011, accompanied by a devastating tsunami that caused severe damage to people and infrastructures. There have been many studies on the effects of coastal embankment, breakwater, as well as non-structural solutions such as pine trees, mangrove forest, and coastal dunes for reducing tsunami energy when it spreads to coastal areas. However, researches on sensitivity of coastal embankment structure in relation with tsunami disaster based on tsunami Shields number have not been widely carried out. Thus, the main objectives of this research are to investigate the sensitivity of coastal embankment structure in relation with tsunami disaster. In this study, a NEWFLUME model based on Reynolds Averaged Navier-Stokes (RANS) equations is applied to simulate the recent Great East Japan Earthquake and Tsunami 2011 along the coast of Suzaki. Results of numerical simulation have shown the reduction of tsunami Shields number in front of coastal embankment and landward area approximately 400 meter far from the backside of the embankment. In addition, estimated time of tsunami arrival was delayed due to the effect of various height of coastal embankment.
