Abstract
" The 2011 off the Pacific coast of Tohoku Earthquake" occurred on March 11th in 2011 classified 9.0 in moment magnitude. Due to the earthquake, extensive crustal deformations were observed both the ground and bottom of Pacific Ocean surrounding the focal region. This research divides this earthquake motion for each periodic band by the acceleration response spectrum analysis to make sure what damage caused by earthquake motion. Most of all observation points predominant period show lower than 1sec. And then, we plot the outline of the focal area and draw radial lines to study the acceleration response spectrum transition influenced by the natures of the soil. The weak ground areas, like banking or sandy soil areas, increase the acceleration response spectrum period more than 0.5 sec. Conversely, the strong ground area, likely be made of rock, decrease acceleration response spectrum. On the other hand, we compared the analyzed data with the designed ground motion mentioned in Public Interest Incorporated Association Japan Road Association, Specifications for highway bridges part V. between less than 0.5 sec. period, acceleration response spectrum over the designed ground motion near the focal area observation points.
