Earthquakes and Structures

Techno-Press (테크노프레스)
권호 표지
DOI QR코드

DOI QR Code

Shear strength model for reinforced concrete corbels based on panel response

  • Massone, Leonardo M. (Department of Civil Engineering, University of Chile) ;
  • Alvarez, Julio E. (Department of Civil Engineering, University of Chile)
  • Received : 2016.02.01
  • Accepted : 2016.10.11
  • Published : 2016.10.25
⟨ Previous Next ⟩

Abstract

Reinforced concrete corbels are generally used to transfer loads within a structural system, such as buildings, bridges, and facilities in general. They commonly present low aspect ratio, requiring an accurate model for shear strength prediction in order to promote flexural behavior. The model described here, originally developed for walls, was adapted for corbels. The model is based on a reinforced concrete panel, described by constitutive laws for concrete and steel and applied in a fixed direction. Equilibrium in the orthogonal direction to the shearing force allows for the estimation of the shear stress versus strain response. The original model yielded conservative results with important scatter, thus various modifications were implemented in order to improve strength predictions: 1) recalibration of the strut (crack) direction, capturing the absence of transverse reinforcement and axial load in most corbels, 2) inclusion of main (boundary) reinforcement in the equilibrium equation, capturing its participation in the mechanism, and 3) decrease in aspect ratio by considering the width of the loading plate in the formulation. To analyze the behavior of the theoretical model, a database of 109 specimens available in the literature was collected. The model yielded an average model-to-test shear strength ratio of 0.98 and a coefficient of variation of 0.16, showing also that most test variables are well captured with the model, and providing better results than the original model. The model strength prediction is compared with other models in the literature, resulting in one of the most accurate estimates.

Keywords

References

  1. Abdul-Razzak, A.A. and Mohammed Ali, A.A. (2011), "Influence of cracked concrete models on the nonlinear analysis of High Strength Steel Fibre Reinforced Concrete corbels", Compos. Struct., 93(9), 2277-2287. https://doi.org/10.1016/j.compstruct.2011.03.016
  2. ACI Committee 318 (2014), "Building Code Requirements for Structural Concrete (ACI 318-14) and Commentary (318R-14)", American Concrete Institute, Farmington Hills, Mich.
  3. Canha, R.M.F., Kuchma, D.A., El Debs, M.K. and Souza, R.A. (2014), "Numerical analysis of reinforced high strength concrete corbels", Eng. Struct., 74, 130-144. https://doi.org/10.1016/j.engstruct.2014.05.014
  4. Fattuhi, N.I. and Hughes, B.P. (1989), "Ductility of reinforced concrete corbels containing either steel fibers or stirrups", ACI Struct. J., 86(6), 644-651.
  5. Fattuhi, N.I. (1994), "Reinforced corbels made with plain and fiber concretes", ACI Struct. J., 91(5), 530-536.
  6. Foster, S.J., Powell, R.E. and Selim, H.S. (1996), "Performance of high-strength concrete corbels", ACI Struct. J., 93(5), 555-563.
  7. Gupta, A. and Rangan, B.V. (1998), "High-strength concrete structural walls", ACI Struct. J., 95(2), 194-205.
  8. Her, G.J. (1990), "Study of reinforced high-strength concrete corbels", Master's thesis, Department of Construction Engineering, National Taiwan University of Science and Technology, Taipei, Taiwan. (in Chinese)
  9. Hermansen, B.R. and Cowan, J. (1974), "Modified shear-friction theory for bracket design", ACI J., Proceedings, 71(2), 55-60.
  10. Hernandez, A. (2015), "Verification of the Bernoulli hypothesis in combined reinforced concrete wall sections", Civil engineering thesis, Civil Engineering department, University of Chile. (in Spanish)
  11. Hsu, T.T.C. and Mo, Y.L. (1985), "Softening of concrete in low-rise shearwalls", ACI Struct. J., 82(6), 883-889.
  12. Hwang, S.J., Lu, W.Y. and Lee, H.J. (2000a), "Shear strength prediction for reinforced concrete corbels", ACI Struct. J., 97(4), 543-552.
  13. Hwang, S.J., Yu, H.W. and Lee, H.J. (2000b), "Theory of interface shear capacity of reinforced concrete", J. Struct. Eng., 126(6), 700-707. https://doi.org/10.1061/(ASCE)0733-9445(2000)126:6(700)
  14. Hwang, S.J., Fang, W.H., Lee, H.J. and Yu, H.W. (2001), "Analytical model for predicting shear strength of squat walls", J. Struct. Eng., 127(1), 43-50. https://doi.org/10.1061/(ASCE)0733-9445(2001)127:1(43)
  15. Kang, T.H.-K., Kim, W., Massone, L.M. and Galleguillos, T.A. (2012), "Shear-flexure coupling behavior of steel fiber-reinforced concrete beams", ACI Struct. J., 109(4), 435-444.
  16. Kassem, W. and Elsheikh, A. (2010), "Estimation of shear strength of structural shear walls", J. Struct. Eng., 136(10), 1215-1224. https://doi.org/10.1061/(ASCE)ST.1943-541X.0000218
  17. Kassem, W. (2015), "Strength prediction of corbels using Strut-and-Tie model analysis", Int. J. Concrete Struct. Mater., 9(2), 255-266. https://doi.org/10.1007/s40069-015-0102-y
  18. Kriz, L.B. and Raths, C.H. (1965), "Connections in precast concrete structures-strength of corbels", PCI/ J., 10(1), 16-61. https://doi.org/10.15554/pcij.02011965.16.61
  19. Kumara, S. and Barai, S.V. (2010), "Neural networks modeling of shear strength of SFRC corbels without stirrups", Appl. Soft Comput., 10(1), 135-148. https://doi.org/10.1016/j.asoc.2009.06.012
  20. Lu, W.-Y., Lin, I.-J. and Hwang, S.-J. (2009), "Shear strength of reinforced concrete corbels", Magaz. Concrete Res., 61(10), 807-813. https://doi.org/10.1680/macr.2008.61.10.807
  21. Massone, L.M., Gotschlich, N.J., Kang T.H.-K. and Hong, S.-G. (2013), "Shear-flexural interaction for prestressed self-consolidating concrete beams", Eng. Struct., 56, 1464-1473. https://doi.org/10.1016/j.engstruct.2013.07.019
  22. Massone, L.M. (2010), "Strength prediction of squat structural walls via calibration of a shear-flexure interaction model", Eng. Struct., 32(4), 922-932. https://doi.org/10.1016/j.engstruct.2009.12.018
  23. Massone, L.M. and Ulloa, M.A. (2014), "Shear response estimate for squat reinforced concrete walls via a single panel model", Earthq. Struct., 7(5), 647-665. https://doi.org/10.12989/eas.2014.7.5.647
  24. Mattock, A.H., Chen, K.C. and Soongswang, K. (1976), "Behavior of reinforced concrete corbels", PCI J., 21(2), 52-77. https://doi.org/10.15554/pcij.03011976.52.77
  25. Russo, G., Venir, R., Pauletta, M. and Somma, G. (2006), "Reinforced concrete corbels shear strength model and design formula", ACI Struct. J., 103(1), 3-7.
  26. Solanki, H. and Sabnis, G.M. (1987), "Reinforced concrete corbels-simplified", ACI Struct. J., 84(5), 428-432.
  27. Vecchio, F. and Collins, M.P. (1986), "The modified compression-field theory for reinforced concrete elements subjected to shear", ACI Struct. J., 83(2), 219-231.
  28. Yong, Y.K. and Balaguru, P. (1994), "Behavior of reinforced high-strength concrete corbels", J. Struct. Eng., ASCE, 120(4), 1182-1201. https://doi.org/10.1061/(ASCE)0733-9445(1994)120:4(1182)
  29. Zhang, L.-X.B. and Hsu, T.T.C. (1998), "Behavior and analysis of 100 MPa concrete membrane elements", J. Struct. Eng., 124(1), 24-34. https://doi.org/10.1061/(ASCE)0733-9445(1998)124:1(24)

Cited by

  1. General solution for shear strength estimate of RC elements based on panel response vol.172, pp.None, 2016, https://doi.org/10.1016/j.engstruct.2018.06.038
  2. Analytical model for shear strength estimation of reinforced concrete beam-column joints vol.173, pp.None, 2018, https://doi.org/10.1016/j.engstruct.2018.07.005