Estimation of strong motion at Inohana and Nakasone Viaduct sites for the 2003 Southern Sanriku Earthquake using the main shock observation records

Abstract

Serious damage occurred at Inohana Viaduct site along the Tohoku Shinkansen, Hanamaki City, during the 2003 Southern Sanriku Earthquake (M_J7.1). On the other hand, during the same eathquake, the nearby Nakasone Viaduct in Kitakami City did not suffer significant damage. In order to reveal the cause of of different performance of these structures, it is important to evaluate strong ground motions at the both viaduct sites. In this study, seismic waveforms at the viaduct sites were estimated based on the aftershock records at the viaduct sites and the main shock records at the nearby strong motion stations. In addition, the accuracy of the estimation methods with and without the aftershock records was discussed.