Abstract
Many studies on stability of breakwaters against tsunami were carried out after the Tohoku region pacific coast earthquake tsunami. However, the applicability of the result of these studies to a breakwater with small depth of water on a coral reef is not confirmed. The examination result about the stability of a breakwater on a coral reef against tsunami is reported in this paper. Hydraulic model test and numerical simulation was carried out to verify the stability of a breakwater on a coral reef. The constant which shows the stability of armor units covering breakwater rubble mounds was a little larger result than the value generally used. An inversion phenomenon may be occurred at the size and stability of the armor units.
