Regional study on structural dynamic property of buildings in China

Abstract

SUMMARY Full‐scale in situ ambient vibration tests have been performed in different regions of China since 2008. Reliable data on 35 buildings in the Sichuan province and 18 buildings in Shanghai have been used for identifying the structural dynamic properties. Every building was tested twice, at time intervals of 1 to 2 years. This paper first describes the statistical analysis results of the measured records and then the time–frequency domain analysis on dynamic responses of a specific monitored building subjected to strong motion. Furthermore, the estimated dynamic characteristics of the buildings are presented. The damping ratio shows a period‐dependent characteristic, and the natural periods of buildings in Sichuan shifted after 2 years. Subsequent discussion on the natural period change phenomenon reveals that the natural period changes are affected by a number of factors, including story number, construction year, loading history, and observation time intervals. The long‐term time effects on concrete, the self‐healing ability of cracked concrete, and the change in soil condition are discussed to explain the natural period wandering. Copyright © 2012 John Wiley & Sons, Ltd.

Accidental eccentricities, frame shear forces and ductility demands of buildings with uncertainties of stiffness and live load

“…of the modal frequencies resulted smaller than 2% and they decreased with the model height. These frequency changes are smaller than those reported by other authors [15][16][17]. Since the accidental eccentricity is the only source of change considered in this study, the frequency changes are small.…”

Health monitoring and field‐testing of high‐rise buildings: A review

“…Therefore, the distinguished value of the application of SHM and St-Id, as called seismic monitoring, has been understood by the earthquake engineering community. 49 Representative work and observations on structural damages and performances during the mainshock and aftershocks can be found in the open literature for the 2008 Wenchuan earthquake by the authors, 50 the 2010 Chile earthquake by Lemnitzer et al, 51 the 2010 Christchurch earthquake by Kuang et al, 52 and the 2011 Tohoku earthquake by Minami et al 53 Table 5 reports the state-of-the-art practice of seismic monitoring on representative high-rise and medium-rise buildings. Similar to the summaries presented in Tables 3 and 4, the application of accelerometer and the use of modal properties as damage features are the feasible choices and applications in the case of seismic monitoring and datadriven analysis.…”

“…Therefore, the distinguished value of the application of SHM and St‐Id, as called seismic monitoring, has been understood by the earthquake engineering community 49 . Representative work and observations on structural damages and performances during the mainshock and aftershocks can be found in the open literature for the 2008 Wenchuan earthquake by the authors, 50 the 2010 Chile earthquake by Lemnitzer et al, 51 the 2010 Christchurch earthquake by Kuang et al, 52 and the 2011 Tohoku earthquake by Minami et al 53 …”