Structural Engineering and Mechanics

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Simplified analytical model for flexural response of external R.C. frames with smooth rebars

  • Campione, Giuseppe (Department of Civil, Environmental, Aerospace and Material Engineering (DICAM) - University of Palermo) ;
  • Cannella, Francesco (Department of Civil, Environmental, Aerospace and Material Engineering (DICAM) - University of Palermo) ;
  • Cavaleri, Liborio (Department of Civil, Environmental, Aerospace and Material Engineering (DICAM) - University of Palermo) ;
  • Monaco, Alessia (Department of Civil, Environmental, Aerospace and Material Engineering (DICAM) - University of Palermo)
  • Received : 2017.12.17
  • Accepted : 2018.02.27
  • Published : 2018.05.25
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Abstract

In this paper an analytical model in a closed form able to reproduce the monotonic flexural response of external RC beam-column joints with smooth rebars is presented. The column is subjected to a constant vertical load and the beam to a monotonically increasing lateral force applied at the tip. The model is based on the flexural behavior of the beam and the column determined adopting a concentrated plasticity hinge model including slippage of the main reinforcing bars of the beam. A simplified bilinear moment-axial force domain is assumed to derive the ultimate moment associated with the design axial force. For the joint, a simple truss model is adopted to predict shear strength and panel distortion. Experimental data recently given in the literature referring to the load-deflection response of external RC joints with smooth rebars are utilized to validate the model, showing good agreement. Finally, the proposed model can be considered a useful instrument for preliminary static verification of existing external RC beam-column joints with smooth rebars for both strength and ductility verification.

Keywords

References

  1. ACI Committee 318 (2011), Building Code Requirements for Structural Concrete ACI 318 and Commentary, American Concrete Institute, Farmington Hills, Michigan, U.S.A.
  2. Attaalla, S.A. (2004), "General analytical model for nominal shear stress of type 2 normal-and high-strength concrete beam-column joints", ACI Struct. J., 101(1), 65-75.
  3. Bakir, P.G. and Boduroglu, H.M. (2002), "A new design equation for predicting the joint shear strength of monotonically loaded exterior beam-column joints", Eng. Struct., 24(8), 1105-1117. https://doi.org/10.1016/S0141-0296(02)00038-X
  4. Braga F., Gigliotti R. and Laterza, M.R.C. (2009), "Existing structures with smooth reinforcing bars: Experimental behaviour of beam-column joints subject to cyclic lateral loads", Open Constr. Build. Technol. J., 3, 52-67. https://doi.org/10.2174/1874836800903010052
  5. Braga, F., Gigliotti, R., Laterza, M., D'Amato, M. and Kunnath, S. (2012), "Modified steel bar model incorporating bond-slip for seismic assessment of concrete structures", J. Struct. Eng., 138(11), 1342-1350. https://doi.org/10.1061/(ASCE)ST.1943-541X.0000587
  6. Calvi, G.M., Magenes, G. and Pampanin, S. (2002), "Relevance of beam-column damage and collapse in RC frame assessment", J. Earthq. Eng., 6(2), 75-100.
  7. Calvi, G.M., Pampanin, S., Moratti, M., Ward, J., Magened, G., Pavese, A. and Rasulo, A. (2001), Seismic Vulnerability Assessment of Existing Concrete Buildings. Experimental Tests on a Three-Story RC Frame, Technical report, University of Pavia, Pavia, Italy.
  8. Campione, G. (2015), "Analytical prediction of load deflection curves of external steel fibers R/C beam-column joints under monotonic loading", Eng. Struct., 83, 86-98. https://doi.org/10.1016/j.engstruct.2014.10.047
  9. D'Amato, M., Braga, F., Gigliotti, R., Kunnath, S. and Laterza, M. (2012), "Validation of a modified steel bar model incorporating bond-slip for seismic assessment of concrete structures", J. Struct. Eng., 138(11), 1342-1350. https://doi.org/10.1061/(ASCE)ST.1943-541X.0000587
  10. Ehsani, M.R. and Wight, J.K. (1985), "Exterior reinforced beam-to-column connection subjected to earthquake-type loading", ACI Struct. J., 82, 492-499.
  11. Fabbrocino, G., Verderame, G.M., Manfredi, G. and Cosenza, E. (2004), "Structural models of critical regions in old type RC frames with smooth rebars", Eng. Struct., 26(14), 2137-2148. https://doi.org/10.1016/j.engstruct.2004.07.018
  12. Fib Bulletin No. 24 (2003), Seismic Assessment and Retrofit of Reinforced Concrete Buildings, State-of-Art Report.
  13. Hegger, J., Sherif, A. and Roeser, W. (2003), "Non-seismic design of beam-column joints", ACI Struct. J., 100(5), 654-664.
  14. Hegger, J., Sherif, A. and Roeser, W. (2004), "Nonlinear finite element analysis of reinforced concrete beam-column connections", ACI Struct. J., 101(5), 604-614.
  15. Hwang, S.J. and Lee, H.J. (1999), "Analytical model for predicting shear strength of exterior reinforced concrete beam-column joints for seismic resistance", ACI Struct. J., 96(5), 846-858.
  16. Kim, J., LaFave, J.M. and Song, J. (2007), "A new statistical approach for joint shear strength determination of RC beam-column connections subjected to lateral earthquake loading", Struct. Eng. Mech., 27(4), 439-456. https://doi.org/10.12989/sem.2007.27.4.439
  17. Laterza, M., D'Amato, M. and Gigliotti, R. (2017), "Modeling of gravity-designed RC sub-assemblages subjected to lateral loads", Eng. Struct., 130, 242-260. https://doi.org/10.1016/j.engstruct.2016.10.044
  18. Park, R. and Paulay, T. (1975), Reinforced Concrete Structures, John Wiley & Sons Inc., New York, U.S.A.
  19. Park, S. and Mosalam, K.M. (2012), "Parameters for shear strength prediction of exterior beam-column joints without transverse reinforcement", Eng. Struct., 36, 198-209. https://doi.org/10.1016/j.engstruct.2011.11.017
  20. Pauletta, M., Di Luca, D. and Russo, G. (2015), "Exterior beam column joints-shear strength model and design formula", Eng. Struct., 94, 70-81. https://doi.org/10.1016/j.engstruct.2015.03.040
  21. Priestley, M.J.N. (1997), "Displacement-based seismic assessment of reinforced concrete buildings", J. Earthq. Eng., 1(1), 157-192. https://doi.org/10.1080/13632469708962365
  22. Russo, G. and Pauletta, M. (2012), "Seismic behavior of exterior beam-column connections with smooth rebars and effects of upgrade", ACI Struct. J., 109(2), 225-233.
  23. Thom, C.W. (1983), "The effects of inelastic shear on the seismic response of structures", Ph.D. Dissertation, University of Auckland, New Zealand.
  24. Unal, M. and Burak, B. (2012), "Joint shear strength prediction for reinforced concrete beam-to-column connections", Struct. Eng. Mech., 41(3), 421-440. https://doi.org/10.12989/sem.2012.41.3.421
  25. Vollum, R. and Parker, D. (2008), "External beam-column joints: Design to Eurocode 2", Mag. Concrete Res., 60(7), 511-521. https://doi.org/10.1680/macr.2007.00126