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Probabilistic models for curvature ductility and moment redistribution of RC beams

  • Baji, Hassan (School of Civil Engineering, The University of Queensland) ;
  • Ronagh, Hamid Reza (School of Civil Engineering, The University of Queensland)
  • Received : 2013.01.16
  • Accepted : 2015.04.27
  • Published : 2015.08.25

Abstract

It is generally accepted that, in the interest of safety, it is essential to provide a minimum level of flexural ductility, which will allow energy dissipation and moment redistribution as required. If one wishes to be uniformly conservative across all of the design variables, curvature ductility and moment redistribution factor should be calculated using a probabilistic method, as is the case for other design parameters in reinforced concrete mechanics. In this study, simple expressions are derived for the evaluation of curvature ductility and moment redistribution factor, based on the concept of demand and capacity rotation. Probabilistic models are then derived for both the curvature ductility and the moment redistribution factor, by means of central limit theorem and through taking advantage of the specific behaviour of moment redistribution factor as a function of curvature ductility and plastic hinge length. The Monte Carlo Simulation (MCS) method is used to check and verify the results of the proposed method. Although some minor simplifications are made in the proposed method, there is a very good agreement between the MCS and the proposed method. The proposed method could be used in any future probabilistic evaluation of curvature ductility and moment redistribution factors.

Keywords

References

  1. ACI 318 (2011), Building Code Requirements for Structural Concrete and Commentary, Farmington Hills, MI, USA.
  2. Attard, M.M. and Stewart, M.G. (1998), "A two parameter stress block for high-strength concrete", ACI. Struct. J., 95(3), 305-316.
  3. Benjamin, J. and Cornell, C. (1975), Probability, Statistics and Decision for Civil Engineers, McGraw-Hill, New York, USA.
  4. Bournonville, M., Dahnke, J. and Darwin, D. (2004), Statistical Analysis of the Mechanical Properties and Weight of Reinforcing Bars, SL 04-1, University of Kansas, Lawrence, KS.
  5. Elnashai, A.S. and Di Sarno, L. (2008), Fundamentals of Earthquake Engineering, The John Wiley & Sons, United Kingdom.
  6. Ho, J.C.M., Kwan, A.K.H. and Pam, H.J. (2004), "Minimum flexural ductility design of high-strength concrete beams", Mag. Concrete. Res., 56(1), 13-22. https://doi.org/10.1680/macr.2004.56.1.13
  7. Kappos, A., Chryssanthopoulos, M. and Dymiotis, C. (1999), "Uncertainty analysis of strength and ductility of confined reinforced concrete members", Eng. Struct., 21(3), 195-208. https://doi.org/10.1016/S0141-0296(97)00181-8
  8. Kwan, A.K.H and Ho, J.C.M. (2010), "Ductility design of high-strength concrete beams and columns", Adv. Struct. Eng., 13(4), 651-664. https://doi.org/10.1260/1369-4332.13.4.651
  9. Lu, Y. and Gu, X. (2004), "Probability analysis of RC member deformation limits for different performance levels and reliability of their deterministic calculations", Struct. Saf., 26(4), 367-389. https://doi.org/10.1016/j.strusafe.2004.01.001
  10. Lu, Y., Gu, X. and Guan, J. (2005), "Probabilistic drift limits and performance evaluation of reinforced concrete columns", J. Struct. Eng. - ASCE, 131(6), 966-978. https://doi.org/10.1061/(ASCE)0733-9445(2005)131:6(966)
  11. Oehlers, D.J., Haskett, M., Ali, M.M. and Griffith, M.C. (2010), "Moment redistribution in reinforced concrete beams", Proceedings of the ICE-Structures and Buildings, 163(3), 165-176. https://doi.org/10.1680/stbu.2010.163.3.165
  12. Park, R. and Paulay, T. (1975), Reinforced Concrete Structures, New York, Wiley.
  13. Silva, P. and Ibell, T. (2008), "Evaluation of moment distribution in continuous fiber-reinforced polymer-strengthened concrete beams", ACI. Struct. J., 105(6), 729-739.
  14. Szerszen, M.M. and Nowak, A.S. (2003), "Calibration of design code for buildings (ACI 318): Part 2-Reliability analysis and resistance factors", ACI. Struct. J., 100(3), 383-391.
  15. Trezos, C. (1997), "Reliability considerations on the confinement of RC columns for ductility", Soil. Dyn. Earthq. Eng., 16(1), 1-8. https://doi.org/10.1016/S0267-7261(96)00033-4
  16. Wilson, J.L. (2009), "The cyclic behaviour of reinforced concrete chimney sections with and without openings", Adv. Struct. Eng., 12(3), 411-420. https://doi.org/10.1260/136943309788708329
  17. Zhao, X.M., Wu, Y.F. and Leung, A. (2012), "Analyses of plastic hinge regions in reinforced concrete beams under monotonic loading", Eng. Struct., 34, 466-482. https://doi.org/10.1016/j.engstruct.2011.10.016

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  1. Curvature ductility prediction of high strength concrete beams vol.66, pp.2, 2015, https://doi.org/10.12989/sem.2018.66.2.195