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Free and Ambient Vibration of Steel-Deck Truss Bridge

강합성 데크 트러스 보도교의 자유진동해석 및 상시진동실험에 관한 연구

  • Received : 2011.06.27
  • Accepted : 2012.05.22
  • Published : 2012.07.30

Abstract

This study describes an analytical and experimental investigation of the pedestrian steel-deck truss bridge in the City of Rochester, New York, U.S.A. This investigation was undertaken to provide assurance that this important bridge continues to be functional for this use. An ambient vibration experiment on full-scale structures is a way of assessing the reliability of the various assumptions employed in the mathematical models used in analysis. It is also the most reliable way of determining the structural parameters of major importance in structural dynamics, such as the mode shapes and the associated natural frequencies. Pedestrian-induced vibrations have been measured on the bridge to determine the displacement and the vertical and transverse dynamic characteristics of the steel deck truss. In the analytical modeling, three-dimensional finite element analysis was developed and validated against the ambient tests.

본 연구에서는 미국 뉴욕주 로체스터시 소재 강합성 데크 트러스 보도교를 대상으로 사용성을 평가하기 위한 상시진동 실험(ambient vibration test)을 수행하였고 이를 해석적 방법에 의한 결과와 비교하였다. 교량전체에 대한 상시진동실험은 수치모델 작성 시 도입되는 여러 가정들에 대한 타당성을 평가하는데 있어서 유용한 방법이며, 교량의 고유진동수나 모드형상과 같이 구조 동력학에서 중요한 구조적인 변수를 결정하는데 있어 중요한 역할을 한다. 본 연구에서는 교량의 수직방향 및 수평방향 진동 특성과 변위를 측정하기 위하여 실제 교량에서 보행자에 의해 발생하는 진동을 입력하중으로 사용하였다. 교량 구조물에 대한 모델링을 위하여 3차원 유한 요소법을 사용하여 해석을 수행하였으며, 이를 통하여 현장실험 결과와의 유효성을 입증하였다.

Keywords

References

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