[S-SS26] 地震波伝播：理論と応用

[SSS26-P15] 高層ビルの減衰特性の抽出のための逆重畳法を用いた地震波干渉法の応用

ポスター講演3分口頭発表枠

*呉 浩¹、正木 和明²、入倉 孝次郎¹ (1.愛知工業大学地域防災研究センター、2.愛知工業大学都市環境学科)

キーワード：逆重畳法, Q値, 常時微動, 高層ビル

Deconvolution interferometry has been proved an effective method over cross correlation interferometry and coherence interferometry to monitor the health of buildings, extracting the shear velocity and quality factor from earthquake ground motion data or microtremor data (Snieder and Safak, BSSA, Vol. 96 (2), 2006; Nakata et al., BSSA, Vol.103 (3), 2013); Nakata and Snieder, BSSA, Vol. 104(1), 2014). Wang et al. (JAEE, Vol. 13(2), 2013) extended this method to monitor a multi-story damaged building in stricken city with microtremor by extracting the story-by-story shear velocity propagated inside the building during the 2011 Tohoku earthquake. However, the application of this method to estimating the quality factor of the buildings has not been fully investigated.

In this study, we focus on extracting the quality factor of shear waves from deconvolved waves with reference record on the ground floor. We conducted the microtremor measurement simultaneously in five floors for an hour by employing five sets of velocity seismometers with an 800 Hz record logger in several high-rise buildings being over 20 stories. The measurement is accomplished by moving four sets of equipment sequentially with one set fixed at the reference floor. The extracted quality factors of the buildings are expected to provide a reference for damping factor in the analysis of structural response.