Since shore protection, a breakwater, etc. of a seaside area or an offshore artificial island are built underwater, they will be influenced which is different from a structure on land in case of an earthquake.
The oscillating table on which this institution was installed in the bottom of a tank,3m long, the side of 3m, a depth of 2m,
vibrates by three dimensions of the level 2 directions and perpendicular 1 direction the �}30cm of the maximum serious grades, and maximum acceleration�}2G.
Using this equipment, earthquake power is made to act on the model of an institution, and the influence of an underwater earthquake is studied.