Journal of Korean Society of Steel Construction (한국강구조학회 논문집)

Korean Society of Steel Construction (한국강구조학회)
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A Damage Assessment Technique for Bridges Using Static Displacements

정적변위를 이용한 교량의 손상도 평가기법

  • Received : 2002.06.26
  • Published : 2002.10.27
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Abstract

A new damage detection technique using static displacement data was developed, in order to assess the structural integrity of bridge structures. In conventional damage assessment techniques using dynamic response, the variation of natural frequencies is intrinsically insensitive to the damage of the bridge: thus, it is usually difficult to obtain them from the measured data. The proposed detection method enables the estimation of the stiffness reduction of bridges using the static displacement data that are measured periodically, without requiring a specific loading test. Devices such as a laser displacement sensor can be used to measure static displacement data due to the dead load of the bridge structure. In this study, structural damage was represented by the reduction in the elastic modulus of the element. The damage factor of the element was introduced to estimate the stiffness reduction of the bridge under consideration. Likewise, the proposed algorithm was verified using various numerical simulations and compared with other damage detection methods. The effects of noise and number of damaged elements on damage detection were also investigated. Results showed that the proposed algorithm efficiently detects damage on the bridge.

본 논문에서는 정적 처짐데이터를 이용한 교량의 강성추정에 관한 기법을 개발하였다. 제안된 기법은 주기적으로 교량의 자중에 의한 처짐을 계측하여 이들 처짐값의 변화량을 이용하여 손상의 진행정도를 규명하는 기법으로써 재하시험이 필요하지 않으며, 최근 활발히 진행되고 있는 계측모니터링 시스템으로부터 획득된 계측데이터를 정량적으로 분석하는 기법으로 활용이 가능하리라 판단된다. 손상평가를 위한 정식화과정에서 부재의 손상은 강성의 저감으로 표현하였으며, 부재의 질량과 초기강성은 실측 또는 도면을 통하여 획득이 가능하다고 가정하였다. 제안된 기법의 타당성 검증을 위하여 수치모형을 통한 손상도 추정결과를 제시하였으며, 기존의 손상도 추정기법 중 비교적 손상에 대한 민감도가 높은 모드형상을 이용한 기법과 손상도 추정결과를 비교하였다. 또한, 손상추정결과를 정확도를 감소시키는 노이즈의 영향을 분석하기 위하여 정적응답자료에 백색잡음을 추가하여 손상도를 추정하였으며, 손상부재의 수가 손상추정 결과에 미치는 영향을 검토하였다.

Keywords

References

  1. Damage Identification and health monitoring of structural and mechanical systems from changes in their vibration characteristics : a literature review Doebling, S.W.;Farrar, C.R.;Prime, M.B.;Shevitz, D.W.
  2. J. of Strain Analysis v.14 no.2 The location of deffects in structures from measurements of natural frequencies Cawley, P.;Adams, R.D.
  3. Identification of structural damage from natural frequency measurements Hassiotis, S.
  4. J. of Engineering Mechanics v.126 no.7 Damage detection in beam structures based on frequency measurements Fabrizio, V.;Danilo, C.
  5. J. of KSCE v.22 no.1-A A study on the damage detection of the structures using optimization technique in frequency domain (I) - Modeling of damages Lee, J.S.;Choi. I.Y.;Moon, D.Y.;Lee, H.H.
  6. J. of KSCE v.22 no.1-A A study on the damage detection of the structures using optimization technique in frequency domain (II) - Verification Lee, J.S.;Choi, I.Y.;Cho, H.N.;Paik, S.W.
  7. Proceedings of ASCE 10th Structures Congress An efficient and robust algorithm for damage localizaton in offshore platforms Stubbs, N.;Kim, J.T.;Topole, K.
  8. International J. Offshore and Polar Engineering v.5 no.1 Damage detection in offshore jacket structures from limited modal information Kim, J.T.;Stubbs, N.
  9. New method for structural damage identification using experimental modal analysis Khaled, A.A.N.
  10. J. of Struct. Mech. v.8 no.2 Identification of nonlinear structural dynamic systems Yun, C.B.;Shinozuka, M.
  11. Element level time domain system identification technique with unknown input information Wang, D.
  12. Structural Damage Identification with unknown input and Limited Observation, APSSRA99 Cho, H.N.;Choi, Y.M.
  13. J. of KSCE v.21 no.5-A A Study on the Estimation of Global Stiffness and Damping Matrices in the Time Domain Choi, I.Y.;Lee, J.S.;Moon, D.Y.;Cho, H.N.
  14. Bridge damage detection using a system identification method Wirat, L.