Experimental Study on Pressure Distribution along Landward Slope of Coastal Dike Due to Tsunami Overflow

Abstract

The 2011 off the Pacific coast of Tohoku Earthquake Tsunami caused serious damages to a lot of coastal dikes covered with concrete. In this study, abrasion mechanisms of concrete which cover the landward slope of coastal dikes are focused. Wave flume experiments to measure the water pressure acting on the cover of coastal dikes by overflow of tsunamis were conducted. It is shown that when the landward slope of coastal dike is steep, water pressure acting on the covering concrete may decrease by the influence of centrifugal force on tsunami overflow, and this decrease of water pressure may cause the coastal dike failure.