標題: Identifying the Modal Parameters of a Structure from Ambient Vibration Data via the Stationary Wavelet Packet
作者: Su, W. C.
Huang, C. S.
Chen, C. H.
Liu, C. Y.
Huang, H. C.
Le, Q. T.
土木工程學系
Department of Civil Engineering
公開日期: 1-十一月-2014
摘要: Ambient vibration tests are conducted widely to estimate the modal parameters of a structure. The work proposes an efficient wavelet-based approach to determine the modal parameters of a structure from its ambient vibration responses. The proposed approach integrates the time series autoregressive (AR) model with the stationary wavelet packet transform. In addition to providing a richer decomposition and allowing for an improved time-frequency localization of signals over that of the discrete wavelet transform, the stationary wavelet packet transform also has significantly higher computational efficiency than the wavelet packet transform in terms of decomposing time-shifted signals because the former has a time-invariance property. The correlation matrices needed in determining the coefficient matrices in an AR model are established in subspaces expanded by stationary wavelet packets. The formulation for estimating the correlation matrices is shown for the first time. Because different subspaces contain signals with different frequency subbands, the fine filtering property enhances the ability of the proposed approach to identify not only the modes with strong modal interference, but also many modes from the responses of very few measured degrees of freedom. The proposed approach is validated by processing the numerically simulated responses of a seven-floor shear building, which has closely spaced modes, with considering the effects of noise and incomplete measurements. Furthermore, the present approach is employed to process the velocity responses of an eight-storey steel frame subjected to white noise input in a shaking table test and ambient vibration responses of a cable-stayed bridge.
URI: http://dx.doi.org/10.1111/mice.12115
http://hdl.handle.net/11536/123948
ISSN: 1093-9687
DOI: 10.1111/mice.12115
期刊: COMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING
Volume: 29
Issue: 10
起始頁: 738
結束頁: 757
顯示於類別:期刊論文


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  1. 000343931800002.pdf