Vibration-Based Monitoring of Prestress-Loss in PSC Girder Bridges

PSC 거더교의 진동기반 긴장력 손실 모니터링

  • Published : 2008.02.28

Abstract

A vibration-based monitoring system is newly proposed to predict the loss of prestress forces in prestressed concrete (PSC) girder bridges. Firstly, a global damage alarming algorithm is newly proposed to monitor the occurrence of prestress-loss by using the change in frequency responses. Secondly, a prestress-loss prediction algorithm is selected to estimate the extent of prestress-loss by using the change in natural frequencies. Finally, the feasibility of the proposed system is experimentally evaluated on a scaled PSC girder model for which acceleration responses were measured for several damage scenarios of prestress-loss.

본 논문에서는 프리스트레스 콘크리트(PSC) 거더교의 긴장력 손실을 예측하기 위한 진동기반 모니터링 체계를 제안하였다. 제안한 체계는 긴장력 손실 경보 단계와 긴장력 손실 정도를 평가하는 단계로 구성하였다. 먼저, 긴장력 손실 경보를 위해 두 위치에서 취득된 주파수 응답의 변화를 사용하여 긴장력 손실의 발생을 모니터링하는 새로운 전역적 손상경보기법을 제안하였다. 제안된 기법은 응답신호의 파워스펙트럼만을 이용하기 때문에 별도의 모드해석과정 없이 실시간으로 손상경보가 가능하다. 다음으로, 긴장력 손실 정도를 평가하기 위하여 고유진동수의 변화로부터 긴장력의 상대적인 손실 정도를 평가할 수 있는 긴장력 손실 예측 기법을 선정하였다. 제안된 체계의 유용성을 축소 모형 PSC 거더에 대한 실험을 통해 평가하였다.

Keywords

References

  1. Adams, R.D., Cawley, P., Pye, C.J., Stone, B.J. (1978) A Vibration Technique for Non-destructively Assessing the Integrity of Structures, Journal of Mechanical Engineering Science, 20, pp. 93-100 https://doi.org/10.1243/JMES_JOUR_1978_020_016_02
  2. Bendat, J.S., Piersol, A.G. (1993), Engineering applications of correlation and spectral analysis, Wiley, USA
  3. Brinker, R., Zhang, L., Andersen, P. (2001) Modal Identification of output-only Systems using frequency Domain Decomposition, Smart Materials and Structures, 10, pp.441-445 https://doi.org/10.1088/0964-1726/10/3/303
  4. Doebling, S.W., Farrar, C.R., Prime, M.B. (1998) A summary review of vibration-based damage identification methods, The Shock Vibration Digest, 30(2), pp.91-105 https://doi.org/10.1177/058310249803000201
  5. Kim, J.T., Ryu, Y.S., Cho, H.M., Stubbs, N. (2003a) Damage identification in beam-type structures: frequency-based method vs mode-shapebased method, Engineering Structures, 25, pp.57-67 https://doi.org/10.1016/S0141-0296(02)00118-9
  6. Kim, J.T., Yun, C.B., Ryu, Y.S., Cho, H.M. (2003b) Identification of prestress-loss in PSC beams using modal information, Structural Engineering and Mechanics, 17(3-4), pp.467-482
  7. Kim, J.T., Stubbs, N. (1995) Improved Damage identification Method based on Modal Information, Journal of Sound and Vibration, 259(1), pp. 57-67
  8. Law, S.S., Lu, J.R. (2005) Time domain responses of a prestressed beam and prestress identification, Journal of Sound and Vibration, 288(4-5), pp. 1011-1025 https://doi.org/10.1016/j.jsv.2005.01.045
  9. Lin, T.Y. (1963) Design of Prestressed Concrete Structures, John Wiley & Sons, USA
  10. Miyamoto, A., Tei, K., Nakamura, H., Bull, J.W. (2000) Behavior of prestressed beam strengthened with external tendons, Journal of Structural Engineering, 126, pp.1033-1044 https://doi.org/10.1061/(ASCE)0733-9445(2000)126:9(1033)
  11. Nawy, E.G. (1996) Prestress Concrete - A Fundamental Approach, Prentice Hall, USA
  12. Saiidi, M., Douglas, B., Feng, S. (1994) Prestress force effect on vibration frequency of concrete bridges, Journal of Structure Engineering, 120, pp.2233-2241 https://doi.org/10.1061/(ASCE)0733-9445(1994)120:7(2233)
  13. Saiidi, M., Shield, J., O'connor, D., Jutchens, E. (1996) Variation of prestress force in a prestressed concrete bridge during the first 30 months, PCI Journal, 41, pp.66-72 https://doi.org/10.15554/pcij.09011996.66.72
  14. Stubbs, N., Osegueda, R. (1990) Global nondestructive damage evaluation in solids, International Journal of Analytical and Experimental Modal Analysis, 5(2), pp.67-79
  15. Yi, J. H., Yun, C. B. (2004) Comparative Study on Modal Identification Methods using Output-only Information, Structural Engineering and Mechanics, 17(3-4), pp.445-446 https://doi.org/10.12989/sem.2004.17.3_4.445