Techno Press
You logged in as Techno Press

Wind and Structures
  Volume 14, Number 3, May 2011 , pages 221-238
DOI: https://doi.org/10.12989/was.2011.14.3.221
 


Identification of flutter derivatives from full-scale ambient vibration measurements of the Clifton Suspension Bridge
Nikolaos Nikitas, John H.G. Macdonald and Jasna B. Jakobsen

 
Abstract
    The estimated response of large-scale engineering structures to severe wind loads is prone to modelling uncertainties that can only ultimately be assessed by full-scale testing. To this end ambient vibration data from full-scale monitoring of the historic Clifton Suspension Bridge has been analysed using a combination of a frequency domain system identification method and a more elaborate stochastic identification technique. There is evidence of incipient coupling action between the first vertical and torsional modes in strong winds, providing unique full-scale data and making this an interesting case study. Flutter derivative estimation, which has rarely previously been attempted on full-scale data, was performed to provide deeper insight into the bridge aerodynamic behaviour, identifying trends towards flutter at higher wind speeds. It is shown that, as for other early suspension bridges with bluff crosssections, single-degree-of-freedom flutter could potentially occur at wind speeds somewhat below requirements for modern designs. The analysis also demonstrates the viability of system identification techniques for extracting valuable results from full-scale data.
 
Key Words
    full-scale; system identification; ambient vibration data; flutter derivatives.
 
Address
Nikolaos Nikitas and John H.G. Macdonald : Department of Civil Engineering University of Bristol, University Walk, Bristol, BS8 1TR, UK
Jasna B. Jakobsen : Department of Mechanical and Structural Engineering and Material Science University of Stavanger, N-4036, Stavanger, Norway
 

Techno-Press: Publishers of international journals and conference proceedings.       Copyright © 2024 Techno Press
P.O. Box 33, Yuseong, Daejeon 305-600 Korea, Tel: +82-42-828-7996, Fax : +82-42-828-7997, Email: admin@techno-press.com