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Experimental Mechanics

, Volume 49, Issue 5, pp 743–746 | Cite as

Experimental Testing of a Moving Force Identification Bridge Weigh-in-Motion Algorithm

  • C. W. Rowley
  • E. J. OBrien
  • A. Gonzalez
  • A. Žnidarič
BRIEF TECHNICAL NOTE

Abstract

Bridge weigh-in-motion systems are based on the measurement of strain on a bridge and the use of the measurements to estimate the static weights of passing traffic loads. Traditionally, commercial systems employ a static algorithm and use the bridge influence line to infer static axle weights. This paper describes the experimental testing of an algorithm based on moving force identification theory. In this approach the bridge is dynamically modeled using the finite element method and an eigenvalue reduction technique is employed to reduce the dimension of the system. The inverse problem of finding the applied forces from measured responses is then formulated as a least squares problem with Tikhonov regularization. The optimal regularization parameter is solved using the L-curve method. Finally, the static axle loads, impact factors and truck frequencies are obtained from a complete time history of the identified moving forces.

Keywords

Bridge Weigh-in-motion Force identification Regularization Dynamic programming Traffic loads 

Notes

Acknowledgement

The authors would like to express their gratitude for the financial support received from the European 6th Framework Project ARCHES towards this investigation.

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Copyright information

© Society for Experimental Mechanics 2008

Authors and Affiliations

  • C. W. Rowley
    • 1
  • E. J. OBrien
    • 2
  • A. Gonzalez
    • 2
  • A. Žnidarič
    • 3
  1. 1.Bridges, Buro Happold Ltd.LondonUK
  2. 2.School of Architecture, Landscape and Civil EngineeringUniversity College DublinDublin 4Ireland
  3. 3.Slovenian National Building and Civil Engineering InstituteLjubljanaSlovenia

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