Precise and effective identification of modal parameters is important for a civil structure throughout the structural lifetime. A time-frequency method for modal parameter identification is developed based on a recently developed adaptive method for signal decomposition, i.e., empirical Fourier decomposition (EFD). The EFD is used to separate a multi-component free vibration response into the summation of several mono-component modal responses. The modal frequencies and modal damping ratios are calculated from the modal responses by using the empirical envelope method and a damping estimation method. Two numerical examples and one experimental example are provided to validate the EFD-based time-frequency method and highlight the improvements of the EFD-based method relative to the empirical mode decomposition (EMD)-based method. It is highlighted that the EFD-based method has a much higher frequency resolution and lower computational cost than the EMD-based method. Hence, the proposed EFD-based method is suitable for online modal parameter identifications of structures with closely spaced modes. In addition, the EFD-based method is useful for both linear and nonlinear systems.
Li, S. , Liu, Y. , Wang, P. , Li, X. and Li, Z. (2022). Modal parameter identification for closely spaced modes using an Empirical Fourier decomposition-based method. Scientia Iranica, (), -. doi: 10.24200/sci.2022.60768.6978
MLA
Li, S. , , Liu, Y. , , Wang, P. , , Li, X. , and Li, Z. . "Modal parameter identification for closely spaced modes using an Empirical Fourier decomposition-based method", Scientia Iranica, , , 2022, -. doi: 10.24200/sci.2022.60768.6978
HARVARD
Li, S., Liu, Y., Wang, P., Li, X., Li, Z. (2022). 'Modal parameter identification for closely spaced modes using an Empirical Fourier decomposition-based method', Scientia Iranica, (), pp. -. doi: 10.24200/sci.2022.60768.6978
CHICAGO
S. Li , Y. Liu , P. Wang , X. Li and Z. Li, "Modal parameter identification for closely spaced modes using an Empirical Fourier decomposition-based method," Scientia Iranica, (2022): -, doi: 10.24200/sci.2022.60768.6978
VANCOUVER
Li, S., Liu, Y., Wang, P., Li, X., Li, Z. Modal parameter identification for closely spaced modes using an Empirical Fourier decomposition-based method. Scientia Iranica, 2022; (): -. doi: 10.24200/sci.2022.60768.6978
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