A new approach to identification of structural damping ratios

Fang Lin Huang, Xue Min Wang, Zheng Qing Chen, Xu Hui He, Yiqing Ni

Research output: Journal article publicationJournal articleAcademic researchpeer-review

21 Citations (Scopus)

Abstract

A new approach to identification of modal damping ratios from free vibration response of a linear structure with viscous damping is proposed in this paper. For a single degree of freedom (dof) system, the formulated relations among areas forming from time history of response are used to determine the damping ratio for the free decay vibration. Comparing with traditional logarithmic-decrement method, the approach in this paper has advantages such as stronger anti-noise ability, higher precision, better stability and convenience. For a multi-dof system, the free vibration response measured at one point on the structure is expressed in an analytical form at first, and then multiplied by eat. Giving the initial value, a can be obtained by Newton's dichotomy or golden section method while the product of the response and eathas equal vibration amplitudes after a period of time. Accordingly, the damping ratio for this mode can be determined. Repeating the above-mentioned process, all damping ratios for different modes can be obtained in the same way. Results of digital simulations and field tests for the Dongting Lake Cable-stayed Bridge in Yueyang show that the approach presented in this paper is effective and practical.
Original languageEnglish
Pages (from-to)144-153
Number of pages10
JournalJournal of Sound and Vibration
Volume303
Issue number1-2
DOIs
Publication statusPublished - 5 Jun 2007

ASJC Scopus subject areas

  • Condensed Matter Physics
  • Mechanics of Materials
  • Acoustics and Ultrasonics
  • Mechanical Engineering

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