Earth Planets Space, Vol. 64 (No. 12), pp. 1277-1286, 2012
Kou-Cheng Chen, Jeen-Hwa Wang, Bor-Shouh Huang, Chun-Chi Liu, and Win-Gee Huang
Institute of Earth Sciences, Academia Sinica, P.O. Box 1-55, Nankang, Taipei 11529, Taiwan
(Received December 27, 2011; Revised March 26, 2012; Accepted April 8, 2012; Online published January 28, 2013)
The strong-motion recordings generated by the 11 March
2011, Tohoku, Japan earthquake recorded by the building seismic
array in the TAIPEI 101, the second tallest building in the world,
are more complicated than those at the free-field stations.
Fundamental and higher-mode vibrations can be clearly seen on the
spectra. The fundamental-mode frequency is about 0.15 Hz, which is
the natural frequency of the skyscraper. Spectral ratios of ground
accelerations at the building to those at a nearby borehole station
increase from unity at the fifth floor underground to factors of
110 and 146, respectively, on the 74th and 90th floors above ground
for the fundamental-mode vibrations. The frequency content of accelerograms, recorded on the
fifth floor below ground from the great 2011 Tohoku-Oki earthquake,
appears mainly in a frequency band of 0.015-0.1 Hz, leading to a
fact that the ground motions did not cause high excitation in the
TAIPEI 101 skyscraper.
Key words: Building array, TAIPEI 101, vibration, Tohoku earthquake.