2021 Volume 77 Issue 2 Pages I_109-I_114
Many of the breakwaters were damaged by the 2011 off the Pacific coast of Tohoku Earthquake Tsunami. It is thought that these were caused by the strong current behind the breakwater caused by the overflow at the top of the breakwater, which scoured the foundation mound. However, the technical standards in Japan mainly focus on composite breakwaters, and do not refer to other structural types. In this study, hydraulic model experiments and fluid analysis were conducted to investigate the structural resistiveness against tsunami action of the port side armor blocks of a sloping breakwater with a capping concrete.
As a result, it was found that the location and degree of damage varied depending on the tide level at the time of tsunami attack, and that it was necessary to consider seepage flow in the case of sloping breakwaters.
