Modal Identification of Cable‐Stayed Pedestrian Bridge
Publication: Journal of Structural Engineering
Volume 119, Issue 11
Abstract
The vibrations of a cable‐stayed pedestrian bridge are measured and compared with a numerical model, and used to produce improved estimates of the structural properties. Fourteen deck modes with frequencies under 16 Hz were identified using the impact hammer technique. The damping of all but one of the modes was measured at 0.75%, in spite of a wood deck. The numerical model consisted of a three‐dimensional finite element analysis which incorporated nonlinear cable effects. The experimental and numerical results were shown to be highly correlated by visual inspection, the MAC, and the CoMAC. The primary differences were: (1) Two of the experimental mode shapes showed a slight asymmetry that was not present in the numerical modes; and (2) the measured natural frequencies were consistently higher than the numerical frequencies. Parameter estimation using eigenvalue sensitivities with changes of less than 12% in the nominal values helps reconcile the experimental and numerical differences.
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Information & Authors
Information
Published In
Journal of Structural Engineering
Volume 119 • Issue 11 • November 1993
Pages: 3384 - 3404
Copyright
Copyright © 1993 American Society of Civil Engineers.
History
Received: Dec 28, 1990
Published online: Nov 1, 1993
Published in print: Nov 1993
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