Damaged Story Detection and Modal Properties of a RC Building Subjected to 2011 Tohoku Earthquake

Abstract

Focusing on a three storied RC Building which was damaged by 2011 Tohoku Earthquake, we examined its modal properties by analyzing both acceleration records of the main shock and microtremor records observed after the earthquake. The damaged stories were detected from the identified natural modes from the microtremor records. In addition, we estimated the modal parameters by two kinds of frequency domain decomposition technique; one for general viscous damping system, the other for proportional damping system. The influence of viscous damping condition on the identified natural modes was discussed.