Tsunami Damage to Coastal Structures in Tohoku coasts Due to the 2011 off the Pacific Coast of Tohoku Earthquake

The 2011 off the Pacific coast of Tohoku Earthquake and resulting Tsunami caused heavy damage to the Pacific coast regions, especially in Iwate, Miyagi and Fukushima prefectures. This paper describes standard damage to coastal structures in the Kinkazan, Omotehama and Ogihama ports in Ojika Peninsula, Miyagi prefecture. In the Kinkazan port, the breakwater subsided 1.4m because of the earthquake and wave dissipation concrete blocks on the top of the breakwater were heavily damaged by the tsunami. In the Ogihama port, the backwash overturned the seawall parapets. The results of numerical simulation using non-linear shallow water wave theory will be used to discuss the causes of damage to the coastal structures.