Structural Engineering and Mechanics

Techno-Press (테크노프레스)
권호 표지
DOI QR코드

DOI QR Code

Debonding failure analysis of prestressed FRP strengthened RC beams

  • Hoque, Nusrat (Department of Civil Engineering, University Malaya, Jalan University) ;
  • Jumaat, Mohd Z. (Department of Civil Engineering, University Malaya)
  • Received : 2016.09.17
  • Accepted : 2018.03.09
  • Published : 2018.05.25
⟨ Previous Next ⟩

Abstract

Fiber Reinforced Polymer (FRP), which has a high strength to weight ratio, are now regularly used for strengthening of deficient reinforced concrete (RC) structures. While various researches have been conducted on FRP strengthening, an area that still requires attention is predicting the debonding failure load of prestressed FRP strengthened RC beams. Application of prestressing increases the capacity and reduces the premature failure of the beams largely, though not entirely. Few analytical methods are available to predict the failure loads under flexure failure. With this paucity, this research proposes a method for predicting debonding failure induced by intermediate crack (IC) for prestressed FRP-strengthened beams. The method consists of a numerical study on beams retrofitted with prestressed FRP in the tension side of the beam. The method applies modified Branson moment-curvature analysis together with the global energy balance approach in combination with fracture mechanics criteria to predict failure load for complicated IC-induced failure. The numerically simulated results were compared with published experimental data and the average of theoretical to experimental debonding failure load is found to be 0.93 with a standard deviation of 0.09.

Keywords

Acknowledgement

Grant : Strengthening Structural Elements for Load and Fatigue

Supported by : The University of Malaya-Malaysia

References

  1. Achintha, P. and Burgoyne, C. (2008), "Fracture mechanics of plate debonding", J. Compos. Constr., 12(4), 396-404. https://doi.org/10.1061/(ASCE)1090-0268(2008)12:4(396)
  2. Achintha, P. and Burgoyne, C.J. (2009), "Moment-curvature and strain energy of beams with external fiber-reinforced polymer reinforcement", ACI Struct. J., 106(1), 20.
  3. ACI-4402R-08 (2008), Guide for the Design and Construction of Externally Bonded FRP Systems for Strengthening Concrete Structures, Farmington Hill, Michigan, U.S.A.
  4. ACI-CODE (2008), Building Code Requirements for Structural Concrete. Detroit, U.S.A.
  5. Barros, J.A., Taheri, M., Salehian, H. and Mendes, P.J. (2012), "A design model for fibre reinforced concrete beams pre-stressed with steel and FRP bars", Compos. Struct., 94(8), 2494-2512. https://doi.org/10.1016/j.compstruct.2012.03.007
  6. Bazant, Z.P. and Becq-Giraudon, E. (2002), "Statistical prediction of fracture parameters of concrete and implications for choice of testing standard", Cement Concrete Res., 32(4), 529-556. https://doi.org/10.1016/S0008-8846(01)00723-2
  7. Branson, D.E. (1968), Design Procedures for Computing Deflections, Am. Concrete Inst. Journal & Proceedings.
  8. Dai, J.G., Harries, K.A. and Yokota, H. (2008), "A critical steel yielding length model for predicting intermediate crack-induced debonding in FRP-strengthened RC members", Steel Compos. Struct., 8(6), 457-473. https://doi.org/10.12989/scs.2008.8.6.457
  9. El-Hacha, R., Wight, R. and Green, M. (2001), "Prestressed fibre-reinforced polymer laminates for strengthening structures", Progr. Struct. Eng. Mater., 3(2), 111-121. https://doi.org/10.1002/pse.76
  10. Garden, H. and Hollaway, L. (1998), "An experimental study of the failure modes of reinforced concrete beams strengthened with prestressed carbon composite plates", Compos. Part B: Eng., 29(4), 411-424. https://doi.org/10.1016/S1359-8368(97)00043-7
  11. Ghasemi, S., Maghsoudi, A.A., Bengar, H.A. and Ronagh, H.R. (2015), "Flexural strengthening of continuous unbonded post-tensioned concrete beams with end-anchored CFRP laminates", Struct. Eng. Mech., 53(6), 1083-1104. https://doi.org/10.12989/sem.2015.53.6.1083
  12. Gunes, O., Buyukozturk, O. and Karaca, E. (2009), "A fracture-based model for FRP debonding in strengthened beams", Eng. Fract. Mech., 76(12), 1897-1909. https://doi.org/10.1016/j.engfracmech.2009.04.011
  13. Hajihashemi, A., Mostofinejad, D. and Azhari, M. (2011), "Investigation of RC beams strengthened with prestressed NSM CFRP laminates", J. Compos. Constr., 15(6), 887-895. https://doi.org/10.1061/(ASCE)CC.1943-5614.0000225
  14. Hearing, B.P. (2000), "Delamination in reinforced concrete retrofitted with fiber reinforced plastics", Ph.D. Dissertation, Massachusetts Institute of Technology, U.S.A.
  15. Hognestad, E. (1951), Study of Combined Bending and Axial Load in Reinforced Concrete Members, University of Illinois, Engineering Experiment Station, Bulletin, No. 399.
  16. Kara, I.F., Ashour, A.F. and Koroglu, M.A. (2016), "Flexural performance of reinforced concrete beams strengthened with prestressed near-surface-mounted FRP reinforcements", Compos. Part B: Eng., 91, 371-383. https://doi.org/10.1016/j.compositesb.2016.01.023
  17. Lu, X., Teng, J., Ye, L. and Jiang, J. (2007), "Intermediate crack debonding in FRP-strengthened RC beams: FE analysis and strength model", J. Compos. Constr., 11(2), 161-174. https://doi.org/10.1061/(ASCE)1090-0268(2007)11:2(161)
  18. Malek, A.M., Saadatmanesh, H. and Ehsani, M.R. (1998), "Prediction of failure load of R/C beams strengthened with FRP plate due to stress concentration at the plate end", ACI Struct. J., 95(2), 142-152.
  19. Matthys, S. (2000), Structural Behaviour and Design of Concrete Members Strengthened with Externally Bonded FRP Reinforcement, Ghent University, Belgium.
  20. Niu, H. and Wu, Z. (2001), "Interfacial debonding mechanism influenced by flexural cracks in FRP-strengthened beams", J. Struct. Eng., 47, 1277-1288.
  21. Nordin, H. and Taljsten, B. (2006), "Concrete beams strengthened with prestressed near surface mounted CFRP", J. Compos. Constr., 10(1), 60-68. https://doi.org/10.1061/(ASCE)1090-0268(2006)10:1(60)
  22. Oehlers, D., Nguyen, N.T. and Bradford, M.A. (2000a), "Retrofitting by adhesive bonding steel plates to the sides of RC beams. Part 1: Debonding of plates due to flexure", Struct. Eng. Mech., 9(5), 491-504. https://doi.org/10.12989/sem.2000.9.5.491
  23. Oehlers, D., Nguyen, N.T. and Bradford, M.A. (2000b), "Retrofitting by adhesive bonding steel plates to the sides of RC beams. Part 2: Debonding of plates due to shear and design rules", Struct. Eng. Mech., 9(5), 505-518. https://doi.org/10.12989/sem.2000.9.5.505
  24. Oudah, F. and El-Hacha, R. (2011), "Fatigue strength prediction of RC beams strengthened in flexure using prestressed NSM CFRP strips", Spec. Publ., 275, 1-20.
  25. Pellegrino, C. and Modena, C. (2009), "Flexural strengthening of real-scale RC and PRC beams with end-anchored pretensioned FRP laminates", ACI Struct. J., 106(3), 319.
  26. Peng, H., Zhang, J., Cai, C. and Liu, Y. (2014), "An experimental study on reinforced concrete beams strengthened with prestressed near surface mounted CFRP strips", Eng. Struct., 79, 222-233. https://doi.org/10.1016/j.engstruct.2014.08.007
  27. Quantrill, R. and Hollaway, L. (1998), "The flexural rehabilitation of reinforced concrete beams by the use of prestressed advanced composite plates", Compos. Sci. Technol., 58(8), 1259-1275. https://doi.org/10.1016/S0266-3538(98)00002-5
  28. Raafat, E.H. and Mohamed, G. (2011), "Flexural strengthening of reinforced concrete beams using prestressed, near-surface-mounted CFRP bars", PCI J., 56(4), 134-151. https://doi.org/10.15554/pcij.09012011.134.151
  29. Rahimi, H. and Hutchinson, A. (2001), "Concrete beams strengthened with externally bonded FRP plates", J. Compos. Constr., 5(1), 44-56. https://doi.org/10.1061/(ASCE)1090-0268(2001)5:1(44)
  30. Rezazadeh, M., Barros, J. and Costa, I. (2015), "Analytical approach for the flexural analysis of RC beams strengthened with prestressed CFRP", Compos. Part B: Eng., 73, 16-34. https://doi.org/10.1016/j.compositesb.2014.12.016
  31. Rezazadeh, M., Barros, J.A. and Ramezansefat, H. (2016), "End concrete cover separation in RC structures strengthened in flexure with NSM FRP: Analytical design approach", Eng. Struct., 128, 415-427. https://doi.org/10.1016/j.engstruct.2016.09.062
  32. Rezazadeh, M., Costa, I. and Barros, J. (2014), "Influence of prestress level on NSM CFRP laminates for the flexural strengthening of RC beams", Compos. Struct., 116, 489-500. https://doi.org/10.1016/j.compstruct.2014.05.043
  33. Rosenboom, O. and Rizkalla, S. (2008), "Modeling of IC debonding of FRP-strengthened concrete flexural members", J. Compos. Constr., 12(2), 168-179. https://doi.org/10.1061/(ASCE)1090-0268(2008)12:2(168)
  34. Sebastian, W.M. (2001), "Significance of midspan debonding failure in FRP-plated concrete beams", J. Struct. Eng., 127(7), 792-798. https://doi.org/10.1061/(ASCE)0733-9445(2001)127:7(792)
  35. Teng, J., Lu, X., Ye, L. and Jiang, J. (2004), Recent Research on Intermediate Crack Debonding in FRP-Strengthened RC Beams.
  36. Teng, J., Smith, S.T., Yao, J. and Chen, J. (2003), "Intermediate crack-induced debonding in RC beams and slabs", Constr. Build. Mater., 17(6), 447-462. https://doi.org/10.1016/S0950-0618(03)00043-6
  37. Teng, J., Zhang, J. and Smith, S.T. (2002), "Interfacial stresses in reinforced concrete beams bonded with a soffit plate: A finite element study", Constr. Build. Mater., 16(1), 1-14. https://doi.org/10.1016/S0950-0618(01)00029-0
  38. TR-55 (2012), The Concrete Society (UK): Technical Report No. 55-Design Guidance for Strengthening Concrete Structures Using Fibre Composite Materials.
  39. Wang, C. and Ling, F. (1998), "Prediction model for the debonding failure of cracked RC beams with externally bonded FRP sheets", Proceedings of the 2nd International Conference on Composites in Infrastructure.
  40. Woo, S.K., Nam, J.W., Kim, J.H.J., Han, S.H. and Byun, K.J. (2008), "Suggestion of flexural capacity evaluation and prediction of prestressed CFRP strengthened design", Eng. Struct., 30(12), 3751-3763. https://doi.org/10.1016/j.engstruct.2008.06.013
  41. Xue, W., Tan, Y. and Zeng, L. (2010), "Flexural response predictions of reinforced concrete beams strengthened with prestressed CFRP plates", Compos. Struct., 92(3), 612-622. https://doi.org/10.1016/j.compstruct.2009.09.036
  42. You, Y.C., Choi, K.S. and Kim, J. (2012), "An experimental investigation on flexural behavior of RC beams strengthened with prestressed CFRP strips using a durable anchorage system", Compos. Part B: Eng., 43(8), 3026-3036. https://doi.org/10.1016/j.compositesb.2012.05.030