Abstract
In cases of output-only modal parameter estimation for operational engineering structures, such as aerospace structures, the non-white excitations result in the non-physical modes, which are not able to be identified. For these cases, the recently developed response-transmissibility-based methods of modal parameter estimation are researched and an improved poly-reference response-transmissibility-based output-only approach of modal parameter estimation is proposed. Firstly, the parametric model of the poly-reference response transmissibility is introduced, which is presented by the left matrix fraction polynomials, the formulations of the least square estimation for unknown parameters are proposed, and the normal equation of the least square estimation is reduced by using the block property of the corresponding Jacobian matrix, which largely decreases the computational costs. Secondly, based on the high-dimensional accompany matric method, the eigenvalue problem of the matrix polynomials has been achieved, which results in the solution of the modal parameters. In addition, the original constraints between the number of loading conditions and the number of references is removed by using the pseudo inverse of matrix. Finally, two numerical examples have validated the proposed method. The results illustrate that the proposed method can estimate the modal parameters very well and has the advantage of avoiding the influence of harmonics, which means that the problem of non-white excitations has been solved.
Key words
modal parameter estimation /
output-only /
response transmissibility /
non-white noise excitation
{{custom_keyword}} /
Cite this article
Download Citations
ZHOU Si-Da; LIU Li; YANG Wu; MA Zhi-Sai.
Response-transmissibility-based output-only estimation of structural modal parameters under non-white excitations[J]. Journal of Vibration and Shock, 2014, 33(23): 47-52
{{custom_sec.title}}
{{custom_sec.title}}
{{custom_sec.content}}
{{custom_fnGroup.title_en}}
Footnotes
{{custom_fn.content}}