Abstract
A large earthquake with MJ=7.0 occurred at 10:53 on March 20, 2005 in the westward offshore of Fukuoka Prefecture. Japanese seismic intensities of 6- were recorded at the central and eastern wards of Fukuoka city, Maebara city and Miyaki town. As for structural damage in the central ward of Fukuoka city, structures in Tenjin area suffered slight damage and no structure were found whose main structural members were damaged. In contrast, many structures in Daimyo and Imaizumi areas were damaged, and these areas are located on the irregularly-shaped soil layer. To investigate the reason of the difference in structural damage, we conducted the seismic analysis of ground motion of irregularly-shaped ground using 3-dimensional finite element method.
