한국전산구조공학회논문집 (Journal of the Computational Structural Engineering Institute of Korea)

  • 제17권3호
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  • Pages.251-259
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  • 2004
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  • 1229-3059(pISSN)
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  • 2287-2302(eISSN)
한국전산구조공학회 (Computational Structural Engineering Institute of Korea)
권호 표지

프리스트레스트 콘크리트 교량의 프리스트레스 장기 예측의 불확실성 및 업데이팅

Uncertainty and Updating of Long-Term Prediction of Prestress in Prestressed Concrete Bridges

  • 발행 : 2004.09.01
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⟨ 이전 논문 다음 논문 ⟩

초록

콘크리트의 크리프와 건조수축에 의한 시간에 따른 프리스트레스 장기예측의 정확성은 프리스트레스트 큰크리트 교량과 같은 사회 기반 시설의 유지 관리 및 보수 결정 측면에서 매우 중요한 역할을 한다. 본 논문에서는 프리스트레스트 콘크리트 교량의 프리스트레스 장기예측의 불확실성 감소, 즉 예측의 정확성 향상을 위하여 현장 계측치를 이용하여 베이시안(Bayesian)통계기법을 도입하는 예측기법을 제안하였다. 베이시안 해석시 사전 확률분포는 콘크리트의 크리프와 건조수축의 확률 특성을 고려하여 나타내며, 우도 함수(likelihood function)는 현장에서의 계측치를 사용하여 나타내었다. 시간에 따른 구조적 거동 시스템으로부터의 지속적인 계측 기록은 베이시안 지식 기반에서의 확률분포를 업데이팅 하기 위하여 사용되며, 사후 확률분포는 사전확률분포와 우도 함수를 조합하여 획득한다. 실제로 가설되고 있는 프리스트레스트 콘크리트 박스 거더 교량으로부터 계측된 프리스트레스 힘의 수치 예제해석을 통하여 제안 기법의 적용성을 제시하였다.

The prediction accuracy of prestress plays an important role in the quality of maintenance and the decision on rehabilitation of infrastructure such as prestressed concrete bridges. In this paper, the Bayesian statistical method that uses in-situ measurement data for reducing the uncertainties or updating long-term prediction of prestress is presented. For Bayesian analysis, prior probability distribution is developed to represent the uncertainties of creep and shrinkage of concrete and likelihood function is derived and used with data acquired in site. Posterior probability distribution is then obtained by combining prior distribution and likelihood function. The numerical results of this study indicate that more accurate long-term prediction of prestress forces due to creep and shrink age is possible.

키워드

참고문헌

  1. Madsen, H. O. and Bazant, Z. P., 'Uncertainty analysis of creep and shrinkage effects in concrete structures,' ACI Journal, Vol. 80, No. 2, 1983, pp. 116-127
  2. Bazant, Z. P. and Liu, K. L., 'Random creep and shrinkage in structures : Sampling,' Journal of Structural Engineering, ASCE, Vol. 111, No. 5, 1985, pp. 1113-1134 https://doi.org/10.1061/(ASCE)0733-9445(1985)111:5(1113)
  3. Li, C. Q. and Melchers, R. E., 'Reliability analysis of creep and shrinkage effects,' Journal of Structural Engineering, ASCE, Vol. 118, No. 9, 1992, pp. 2323-2337 https://doi.org/10.1061/(ASCE)0733-9445(1992)118:9(2323)
  4. Bazant, Z. P. and Baweja, S., 'Justification and refinement of Model B3 for concrete creep and shrinkage - 1. Statistics and sensitivity,' Materials and structures, Vol. 28, No. 181, 1995, pp. 415-430
  5. 곽효경, 손제국, 'MSS공법으로 시공되는 교량의 설계모멘트 결정', 한국전산구조공학회논문집, 제14권, 제3호, 2001, pp. 317-327
  6. Zollman, C. C. and Barbaux, S. H., 'Rehabilitation of the Boivre Viaduct - A multispan prestressed box girder bridge,' PCI Journal, Vol. 30, No. 3, 1985, pp. 22-47
  7. Massicotte, B., Picard, A., Gaumond, Y. and Ouellet, C., 'Strengthening of a long span prestressed segmental box girder bridge,' PCI Journal, Vol. 39, No. 3, 1994, pp. 52-65
  8. Steinberg, E. P., 'Probabilistic assessment of prestress loss in pretensioned prestressed concrete,' PCI Journal, Vol. 40, No. 6, 1995, pp. 76-85
  9. Saiidi, M., Hutchens, E. and Gardella, D., 'Bridge prestress losses in dry climate,' Journal of Bridge Engineering, ASCE, Vol. 3, No. 3, 1998, pp. 111-116
  10. Saiidi, M., Shields, J. and O'Connor, D. and Hutchens, E., 'Variation of prestress force in a prestressed concrete bridge during the first 30 months,' PCI Journal, Vol. 41, No. 5, 1996, pp.66-72
  11. Fu, C. C. and Daye, M., 'Statistical prediction of post-tensioning system relaxation based on the in-service surveillance,' Structural Safety, Vol. 9, 1990, pp. 129-137 https://doi.org/10.1016/0167-4730(90)90004-9
  12. Chiu, H. S., Chern, J. C. and Chang, K. C., 'Long-term deflection control in cantilever prestressed concrete bridges Ⅰ : Control method,' Journal of Engineering Mechanics, ASCE, Vol. 122, No. 6, 1996, pp. 489-494 https://doi.org/10.1061/(ASCE)0733-9399(1996)122:6(489)
  13. ACI 209R-92, 'Prediction of creep, shrinkage and temperature effects in concrete structures,' ACI Manual of Concrete Practice, Part 1, American Concrete Institute, Detroit, 1992
  14. Reinhardt, H. W., Pat, M. G. M. and Wittman, F. H., 'Variability of creep and shrinkage of concrete,' Symposium on Fundamental Research on Creep and Shrinkage of Concrete, M. Nijhoff, The Hague, 1982, pp. 75-94
  15. Oh, B. H. and Yang, I. H., 'Sensitivity analysis of time-dependent behavior in PSC box girder bridges,' Journal of Structural Engineering, ASCE, Vol. 126, No. 2, 2000, pp. 171-179 https://doi.org/10.1061/(ASCE)0733-9445(2000)126:2(171)
  16. Iman, R. L. and Helton, J. C., 'A comparison of uncertainty and sensitivity analysis techniques for computer models,' Report NUREG/CR- 3904, SAND84-1461, Sandia National Laboratories, Albuerque, 1985
  17. Geyskens, P., Der Kiureghian, A. and Monteiro, P., 'Bayesian prediction of elastic modulus of concrete,' Journal of Structural Engineering, ASCE, Vol. 124, No. 1, 1998, pp. 8995
  18. Enright, M. P. and Frangopol, D. M., 'Condition prediction of deteriorating concrete bridges using Bayesian updating,' Journal of Structural Engineering, ASCE, Vol. 125, No. 10, 1999, pp. 1118-1125 https://doi.org/10.1061/(ASCE)0733-9445(1999)125:10(1118)
  19. Singhal, A. and Kiremidjian, S., 'Bayesian updating of fragilities with application to RC frames,' Journal of Structural Engineering, ASCE, Vol. 124, No. 8, 1998, pp. 922-929 https://doi.org/10.1061/(ASCE)0733-9445(1998)124:8(922)
  20. Dallal, G. E. and Wilkinson, L., 'An analytic approximation to the distribution of Lilliefors's test statistic for normality,' The American Statistician, Vol. 40, No. 4, 1986, pp. 294-296 https://doi.org/10.2307/2684607