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Shear Behavioral Model based on Shear Deformation Compatibility in Reinforced Concrete Members

전단변형적합조건에 기반한 철근콘크리트 부재의 전단 해석 모델

  • Kim, Woo (Dept. of Civil Engineering, Chonnam National University) ;
  • Rhee, Chang-Shin (Dept. of Civil Engineering, Chonnam National University) ;
  • Jeong, Jae-Pyong (Dept. of Civil Engineering, Chonnam National University)
  • 김우 (전남대학교 토목공학과) ;
  • 이창신 (전남대학교 토목공학과) ;
  • 정제평 (전남대학교 토목공학과)
  • Published : 2006.06.30

Abstract

This paper presents a model for evaluating the contribution by arch action to shear resistance in shear-critical reinforced concrete beams. Based on the relationship between shear and bending moment in beams subjected to combined shear and bending, the behavior of a beam is explicitly divided into two base components of the flexural action and the tied arch action. The compatibility condition of the shear deformation that deviates from Bernoulli bending plane is formulated utilizing the smeared truss idealization with an inclined compression chord. The Modified Compression Filed Theory is employed to calculate the shear deformation of the web, and the relative axial displacements of the compression and the tension chord by the shear flow are also calculated. From this shear compatibility condition in a beam, the shear contribution by the arch action is numerically decoupled. Then the validity of the model is examined by applying the model to some selected test beams in literatures. The results may confirm the rationale of the proposed behavioral model.

본 연구의 목적은 휨과 전단에 지배 받는 철근콘크리트 보에서 아치작용에 의한 전단기여분을 평가하는 모델을 개발하는 것이다. 전단력은 휨모멘트의 변화률이라는 관계식을 기초로, 분산트러스 이상화 기법을 이용하여 횡단면에서 베르누이(Bernoulli) 휨 평면으로부터 전단변형적합조건을 새롭게 유도하였다. MCFT와 분산트러스 이상화를 통해 전단흐름에 의한 복부전단요소의 전단곡률을 일치시키는 전단변형적합조건을 수립하였다. 전단변형적합조건을 이용하면, 보 전단거동은 타이드아치작용과 보 작용의 두 성분으로 수치적 분해 될 수 있다. 그리고 두 기본 작용의 분해가 가능하기 때문에 전단에 지배받는 보의 내력을 예측할 수 있다. 제안 모델의 유효성은 기존 문헌에 수록된 활용 가능한 실험 자료를 통해 검증하였고, 수행 결과는 예측치와 실험치 사이에서 실질적으로 일치하는 결과를 얻었다. 결과의 정확성으로부터 제안 모델의 합리성을 확신할 수 있었다.

Keywords

References

  1. ASCE-ACI Committee 445, 'Recent approaches to shear design of structural concrete,' Journal of Structural Engineering, ASCE, Vol.124, No.5, 1998, pp.1375-1417 https://doi.org/10.1061/(ASCE)0733-9445(1998)124:12(1375)
  2. ASCE-ACI Committee 426, 'The shear strength of reinforced concrete members,' Journal of Structural Division, ASCE, Vol.99, No.6, 1973, pp.1091-1187
  3. ACI Committee 318, 'Building Code Requirement for Rein-forced Concrete and Commentary (318R-99),' ACI, Detroit, M.I 1999, 391pp
  4. Commission of the European Communities, Eurocode No. 2: Design of Concrete Structures, Part I: General rules and Rules for Buildings, ENV 1992-1-1, 1991, 253pp
  5. Comite Euro International Du Beton, CEB-FIP Model Code for Concrete Structures, International system of unified standard codes of practice for structure, Paris, Vol-II, 1978, 348pp
  6. Ramirez, J. A., and Breen, J. A., 'Evaluation of a modified truss-model approach for beams in shear,' ACI Structural Journal, Vol.88, No.5, Sept-Oct. 1991, pp.562-571
  7. Lorentsen, M., 'Theory for the Combined Action of Bending Moment and Shear in Reinforced Concrete and Prestressed Concrete Beams', ACI Journal, Vol.62, No.4, April 1965, pp.403-419
  8. Leonhardt, F., 'Reducing the shear reinforcement in reinforced concrete beams and slabs', Magazine of Concrete Research, Vol.17, No.53, December 1965, pp.187-198 https://doi.org/10.1680/macr.1965.17.53.187
  9. Kani, G. N. J., 'The riddle of shear failure and its solution', ACI Journal, Vol.61, No.4, April 1964, pp.441-467
  10. Marti, P., 'Basic tools of reinforced concrete beam design', ACI Journal, Vol.82, No.1, Jan-Feb, 1985, pp.46-56
  11. Walraven, J., and Lehwalter, N., 'Size effect in short beams loaded in shear', ACI Journal, Vol.91, No.5, Sept.-Oct. 1994, pp.585-593
  12. Niwa., J., 'Lattice model with concrete tension members for shear resisting mechanism of concrete beams,' CEB Bulletin d'Information No.237, 1997, pp.159-170
  13. Vecchio, F. J. and Collins, M. P., 'The modified compression field theory for reinforced concrete elements subjected to shear', ACI Journal, Vol.83, No.2, Mar.-Apr. 1986, pp.219-231
  14. Hsu, T. T. C., Unified theory of reinforced concrete, CRC Press, Boca Raton, Fla. 1993, pp.193-256
  15. Park, R. and Paulay, T., Reinforced concrete structures, Wiley, N. Y., 1975, pp.278-281
  16. Bazant, Z. P. and Kim, J. K., 'Size effect in shear failure of longitudinally reinforced beams', ACI Journal, Vol.81, No.5, Sept.-Oct. 1984, pp.456-468
  17. Belarbi, A. and Hsu, T. T. C., 'Constitutive laws of softened concrete in biaxial tension-compression', ACI Structural Journal, Vol.92, No.5, Sept.-Oct. 1995, pp.562-573
  18. Belarbi, A., and Hsu, T. T. C., 'Constitutive laws of concrete in tension and reinforcing bars stiffened by concrete', ACI Structural Journal, Vol.91, No.4, July-Aug. 1994, pp. 465-474
  19. Kim, D.-J., Kim, W., and White, R. N., 'Prediction of Reinforcement Tension Produced by Arch Action in RC Beams', ASCE Journal of Structural Engineering, Vol. 124, No.6, June 1998, pp.611-622 https://doi.org/10.1061/(ASCE)0733-9445(1998)124:6(611)