DOI QR코드

DOI QR Code

Fiber method analysis of rc beam retrofitted with turnbuckle external post-tensioning

  • Lejano, Bernardo A. (Department of Civil Engineering, De La Salle University)
  • Received : 2015.05.24
  • Accepted : 2015.12.24
  • Published : 2016.01.25

Abstract

Strengthening as well as correcting unsightly deflections of reinforced concrete (RC) beam may be accomplished by retrofitting. An innovative way to do this retrofitting that is proposed in this study utilizes turnbuckle to apply external post-tensioning. This Turnbuckle External Post-Tensioning (T-EPT) was experimentally proven to improve the serviceability and load carrying capacity of reinforced concrete beams. The T-EPT system comprises a braced steel frame and a turnbuckle mechanism to provide the prestressing force. To further develop the T-EPT, this research aims to develop a numerical scheme to analyze the structural performance of reinforced concrete beams with this kind of retrofitting. The fiber method analysis was used as the numerical scheme. The fiber method is a simplified finite element method that is used in this study to predict the elastic and inelastic behavior of a reinforced concrete beam. With this, parametric study was conducted so that the effective setup of doing the T-EPT retrofitting may be determined. Different T-EPT configurations were investigated and their effectiveness evaluated. Overall, the T-EPT was effective in improving the serviceability condition and load carrying capacity of reinforced concrete beam.

Keywords

References

  1. ACI Committee 318 (2008), Building Code Requirements for Structural Concrete and Commentary, Farmington Hills, MI.
  2. Adiaz, P., Vidad, D.J. and Lejano, B. (2011), "Retrofitting of steel wide flange beams using exterior posttensioning", Proceedings of the Science and Technology Congress, Manila, Philippines, February.
  3. Astillero, C., Barretto, I.G., Brillante, C.C., Provido, W. and Lejano, B. (2013), "Experimental evaluation of the structural performance of deformed wide-flanged beam retrofitted with harped exterior posttensioning system", Proceedings of the DLSU Research Congress, Manila, Philippines, March.
  4. Au, F.T.K., Chan, K.H.E., Kwan, A.K.H. and Du, J.S. (2009), "Flexural ductility of prestressed concrete beams with unbonded tendons", Comput. Concrete , 6(6), 451-472. https://doi.org/10.12989/cac.2009.6.6.451
  5. Bennitz, A., Schmidt, J.W., Nilimaa, J., Taljsten, B., Goltermann, P. and Lund Ravn, D. (2012), "Reinforced concrete t-beams externally prestressed with unbonded carbon fiber-reinforced polymer tendons", ACI Struct. J., 109(4), 521-530.
  6. Ciampi, V., Eligenhausen, R., Bertero, V.V. and Popov, E.P. (1982), "Analytical model for concrete anchorages of reinforcing bars under generalized excitation", Report No. UBC/EERC-82/83, Univ. of CA., Berkeley, CA., November.
  7. Daly, A.F. and Witarnawan, W. (1997), "Strengthening of bridges using external post-tensioning", Proceedings of the Eastern Asia Society for Transportation Studies (EASTS), Seoul, Korea, October.
  8. Du, J.S., Au, F.T.K., Cheung, Y.K. and Kwan, A.K.H. (2008), "Ductility analysis of prestressed concrete beams with unbounded tendons", Eng. Struct., 30(1), 13-21. https://doi.org/10.1016/j.engstruct.2007.02.015
  9. El-Shafiey, T. and Atta, A. (2012), "Retrofitting of reinforced concrete beams in shear using external prestressing technique", Mag. Concrete Res., 64(3), 201-211. https://doi.org/10.1680/macr.10.00157
  10. Elrefai, A., West, J. and Soudki, K. (2012), "Fatigue of reinforced concrete beams strengthened with externally post-tensioned cfrp tendons", Constr. Build. Mater., 29, 246-256. https://doi.org/10.1016/j.conbuildmat.2011.10.014
  11. Elrefai, A., West, J. and Soudki, K. (2008), "Effects of overloading on fatigue performance of reinforced concrete beams strengthened with externally post-tensioned carbon-fibre-reinforced polymer tendons", Can. J. Civ. Eng., 35(11), 1294-1307. https://doi.org/10.1139/L08-070
  12. Kaba, S.A. and Mahin, S.A. (1984), "Refined modeling of reinforced concrete columns for seismic analysis:, Report No. UBC/EERC-84/3, Univ. of California, Berkeley, CA, April.
  13. Kim, K.S. and Lee, D.H. (2012), "Flexural behavior model for post-tensioned concrete members with unbonded tendons", Comput. Concrete, 10(3), 241-257. https://doi.org/10.12989/cac.2012.10.3.241
  14. Kitajima, K. (1994), "Study on response characteristics of reinforced concrete building under bidirectional earthquake motions", Doctoral Dissertation, Nihon University, Japan. (in Japanese)
  15. Klaiber, F.W., Dunken, K.F. and Sanders, W.W.Jr (1981), "Feasibility study of strengthening existing single span steel beam concrete deck bridges", Eng. Res., June.
  16. Lee, D.H. and Kim, K.S. (2011), "Flexural strength of prestressed concrete members with unbonded tendons", Struct. Eng. Mech., 38(5), 675-696. https://doi.org/10.12989/sem.2011.38.5.675
  17. Lee, S.H., Shin, K.J. and Kang, T.H.K. (2015), "Flexural strengthening of continuous concrete beams using external prestressed steel bars", PCI J., 60(1), 68-86.
  18. Lee, S.H., Yeo, U.S., Shin, K.J. and Kim, W.J. (2010), "Analytical study on strengthening effect of RC beams strengthened with high-tension steel rod", Struct. Congress, 3590-3601.
  19. Lejano, B.A. (1995), "Study on the flexural and shear behavior of high strength reinforced concrete columns subjected to high and fluctuating axial load", Doctoral Dissertation, Nihon University, Chiba, Japan.
  20. Lejano, B. (2007), "Investigation of biaxial bending of reinforced concrete columns through fiber method modeling", J. Res. Sci. Comput. Eng., 4(3), 61-73.
  21. Lejano, B. (2009), "Modeling the stress-strain relationship of high strength concrete made of local aggregates", Proceedings of the 1st ASEAN Civil Engineering Conference (ACEC), Pattaya, Thailand, AUN-Seed Net, March.
  22. Lou, T. and Xiang, Y. (2006), "Finite element modeling of concrete beams prestressed with external tendons", Eng. Struct., 28(14), 1919-1926. https://doi.org/10.1016/j.engstruct.2006.03.020
  23. Lou, T, Lopes, S.M.R. and Lopes, A.V. (2013), "Flexural response of continuous concrete beams prestressed with external tendons", J. Bridge Eng., 18(6), 525-537. https://doi.org/10.1061/(ASCE)BE.1943-5592.0000392
  24. Mark, K.M.S. and Roesset, J.M. (1976), "Nonlinear dynamic response of reinforced concrete frames," Publication R76-38, Department of Civil Engineering, M.I.T., August.
  25. Matta, F., Nanni, A., Abdelrazaq, A., Gremel, D. and Koch, R. (2009), "Externally post-tensioned carbon frp bar system for deflection control", Constr. Build. Mater., 23(4), 1628-1639. https://doi.org/10.1016/j.conbuildmat.2007.08.002
  26. Mullapudi, T.R.S. and Ayoub, A.S. (2013), "Analysis of reinforced concrete columns subjected to combined axial, flexure, shear and torsional loads", J. Struct. Eng., 139(4), 561-573. https://doi.org/10.1061/(ASCE)ST.1943-541X.0000680
  27. Naghipour, M., Nemati, M. and Doostdar, H.M. (2010), "Experimental study and modeling of reinforced concrete beams strengthened by post-tensioned external reinforcing bars", IJE Tran. A: Basic., 23(2), 127-144.
  28. Nordin, H. (2005), "Strengthening structures with externally prestressed tendons-literature review", Technical Report, Department of Civil and Environmental Engineering, Division of Structural Engineering, Lulea University of Technology, December.
  29. Park, R. and Paulay, T. (1975), Reinforced Concrete Structures, 1st Edition, John Wiley & Sons, Inc., New York, USA.
  30. Penamante, M., Grimares, D., Roxas, J.R., Toral, K.R. and Lejano, B. (2015), "Structural retrofitting of reinforced concrete beams using turnbuckle exterior post-tensioning", Proceedings of the DLSU Research Congress, Manila, Philippines, March.
  31. Shin, K.J., Lee, S.H. and Kang, T.H.K. (2014), "External posttensioning of reinforced concrete beams using a v-shaped steel rod system", J. Struct. Eng., 140(3), 04013067. https://doi.org/10.1061/(ASCE)ST.1943-541X.0000824
  32. Shin, K.J. and Lee, S.H. (2010), "Flexural behaviour of rc beams strengthened with high-tension steel bar", Mag. Concrete Res., 62(2), 137-147. https://doi.org/10.1680/macr.2008.62.2.137
  33. Spacone, E., Filippou, F.C. and Taucer, F.F. (1996), "Fibre beam-column model for nonlinear analysis of r/c frames, part I formulation", Earthq. Eng. Struct. Dy., 25(7), 711-725. https://doi.org/10.1002/(SICI)1096-9845(199607)25:7<711::AID-EQE576>3.0.CO;2-9
  34. Shirai, N., Lejano, B.A., Adachi, H. and Nakanishi, M. (1996), "Flexure and shear behavior of high strength reinforced concrete column subjected to high and fluctuating axial load", Proceedings of the 11th World Conference on Earthquake Engineering, Paper No. 1199, Acapulco, Mexico, June.
  35. Suprenant, B.A. and Malisch, W.R. (2009), Effect of Post-Tensioning on Tolerances, Concrete International Magazine, January.
  36. Tan, K.H. and Kong, D.C. (2009), "A direct design approach for strengthening simple-span beams with external posttensioning", PCI J., 54(4), 48-72.
  37. Toral, K.R. and Lejano, B.A. (2015), "Analyzing the effectiveness of the turnbuckle exterior post-tensioning as a structural retrofitting method using SAP2000", Proceedings of the DLSU Research Congress, Manila, Philippines, March.

Cited by

  1. Friction element for non-linear analysis of friction effect in externally prestressed beams vol.173, pp.3, 2020, https://doi.org/10.1680/jstbu.18.00040