High-order, closely-spaced modal parameter estimation using wavelet analysis

다국어 초록 (Multilingual Abstract)

This study examines the wavelet transform for output-only system identification of ambient excited engineering structures with emphasis on its utilization for modal parameter estimation of high-order and closely-spaced modes. Sophisticated time-frequency resolution analysis has been carried out by employing the modified complex Morlet wavelet function for better adaption and flexibility of the timefrequency resolution to extract two closely-spaced frequencies. Furthermore, bandwidth refinement techniques such as a bandwidth resolution adaptation, a broadband filtering technique and a narrowband filtering one have been proposed in the study for the special treatments of high-order and closely-spaced modal parameter estimation. Ambient responses of a 5-story steel frame building have been used in the numerical example, using the proposed bandwidth refinement techniques, for estimating the modal parameters of the high-order and closely-spaced modes. The first five natural frequencies and damping ratios of the structure have been estimated; furthermore, the comparison among the various proposed bandwidth refinement techniques has also been examined.

참고문헌 (Reference)

1 Kijewski, T.L., "Wavelet transforms for system identification: considerations for civil engineering applications" 18 : 341-357, 2003

2 Yan, B. F., "Wavelet transform-based modal parameter identification considering uncertainty" 291 : 285-301, 2006

3 Chen, S. L., "Wavelet analysis for identification of damping ratios and natural frequency" 323 : 130-147, 2008

4 Daubechies, I., "Ten Lectures on Wavelets"

5 Ruzzene, M., "Natural frequencies and damping identification using wavelet transform: Application to real data" 11 (11): 207-218, 1997

6 Meo, M., "Measurement of dynamic properties of a medium span suspension bridge by using the wavelet transform" 20 : 1112-1133, 2006

7 Ladies, J., "Identification of modal parameters using wavelet transform" 44 : 2263-2283, 2002

8 Tan, J. B., "Identification of modal parameters of a system with high damping and closed spaced modes by combining continuous wavelet transform with pattern search" 22 : 1055-1060, 2008

9 Staszewski, W. J., "Identification of damping in MDOF systems using time-scale decomposition" 203 (203): 283-305, 1997

10 Caracoglia, L., "Experimental comparison of the dynamic performance for steel, aluminum and glass-fiber-reinforced-polymer light poles" 30 (30): 1113-1123, 2008

11 Slavic, J., "Damping identification using a continuous wavelet transform: application to real data" 262 : 291-307, 2003

12 Brincker, R., "Damping estimation by frequency domain decomposition" 2001

13 Kuroiwa, T., "Comparison of modal identification of output-only systems with simultaneous and nonsimultaneous monitoring" 2007

14 Torrence, C., "A practical guide to wavelet analysis" 79 (79): 61-78, 1998

15 Peng, Z. K., "A comparison study of improved Hilbert-Huang transform and wavelet transform: Application to fault diagnosis for rolling bearing" 19 : 974-988, 2005