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Experimental and FE investigation of repairing deficient square CFST beams using FRP

  • Mustafa, Suzan A.A. (Department of Structural Engineering, Faculty of Engineering, Zagazig University)
  • Received : 2018.03.05
  • Accepted : 2018.08.18
  • Published : 2018.10.25

Abstract

This paper handles the repairing of deficient square Concrete-Filled Steel-Tube (CFST) beams subject to bending through an experimental and numerical program. Eight square-CFST beams were tested. A 5-mm artificial notch was induced at mid-span of seven beams, four of them were repaired by using CFRP sheets and two were repaired by using GFRP sheets. The beam deflection, strain and ultimate moments were recorded. It was found that providing different cut-off points for the different layers of FRP sheets prohibited failure at termination points due to stress concentrations. Using different lengths of FRP sheets around the notch retarded crack propagation and prevented FRP rupture at the crack position. Finite element analysis was then conducted and the proposed FE model was verified against the recorded experimental data. The influence of various parameters as FRP sheet length, tensile modulus and the number of layers were studied. The moment capacity of damaged square-CFST beams was improved up to 77.6% when repaired by using four layers of CFRP, however, this caused a dramatic decrease in beam deflection. U-wrapping of notched-CFST beam with 0.75 of its length provided a comparable behaviour as wrapping the full length of the beam.

Keywords

References

  1. Al Zand, A.W., Badaruzzaman, W.H.W., Mutalib, A.A. and Qahtan, A.H. (2015), "Finite element analysis of square CFST beam strengthened by CFRP composite material", Thin-Wall. Struct., 96, 348-358. https://doi.org/10.1016/j.tws.2015.08.019
  2. Al Zand, A.W., Badaruzzaman, W.H.W., Mutalib, A.A. and Hilo, S.J. (2016), "The enhanced performance of CFST beams using different strengthening schemes involving unidirectional CFRP sheets: An experimental study", Eng Struct, 128, 184-198. https://doi.org/10.1016/j.engstruct.2016.09.044
  3. Al Zand, A.W., Badaruzzaman, W.H.W., Mutalib, A.A. and Hilo, S.J. (2017), "Rehabilitation and strengthening of high-strength rectangular CFST beams using a partial wrapping scheme of CFRP sheets: Experimental and numerical study", Thin-Wall. Struct., 114, 80-91. https://doi.org/10.1016/j.tws.2017.01.028
  4. ANSYS (2013), Element Manual; Release 15, Swanson Analysis Systems, Canonsburg, PA, USA.
  5. ASTM-E8/E8M (2009), Standard test methods for tension testing of metallic materials; West Conshohocken, PA, USA.
  6. Chen, T., Qi, M., Gu, X.L. and Yu, Q.Q. (2015), "Flexural strength of carbon fiber reinforced polymer repaired cracked rectangular hollow section steel beams", Int. J. Polym. Sci., 9.
  7. Colombi, P. and Fava, G. (2015), "Experimental study on the fatigue behaviour of cracked steel beams repaired with CFRP plates", Eng. Fract. Mech., 145, 128-142. https://doi.org/10.1016/j.engfracmech.2015.04.009
  8. Deng, J. and Lee, M.M.K. (2007), "Behaviour under static loading of metallic beams reinforced with a bonded CFRP plate", Compos Struct., 78, 232-242. https://doi.org/10.1016/j.compstruct.2005.09.004
  9. Elchalakani, M. (2014a), "CFRP strengthening and rehabilitation of degraded steel welded RHS beams under combined bending and bearing", Thin-Wall. Struct., 77, 86-108. https://doi.org/10.1016/j.tws.2013.12.002
  10. Elchalakani, M. (2014b), "Plastic collapse analysis of CFRP strengthened and rehabilitated degraded steel welded RHS beams subjected to combined bending and bearing", Thin-Wall. Struct., 82, 278-295. https://doi.org/10.1016/j.tws.2014.05.002
  11. Fawzia, S., Al-Mahaidi, R. and Rizkalla, S. (2007), "Strengthening of circular hollow steel tubular sections using high modulus CFRP sheets", Construct. Build. Mater., 21, 839-845. https://doi.org/10.1016/j.conbuildmat.2006.06.014
  12. Gere, J.M. (1997), "Timoshenko SP Mechanics of Materials", PWS, Boston, MA, USA.
  13. Kabir, M.H., Fawzia, S., Chan, A., Gamage, B. and Bai, J.B. (2016), "Experimental and numerical investigation of the behaviour of CFRP strengthened CHS beams subjected to bending", Eng. Struct., 113, 160-173. https://doi.org/10.1016/j.engstruct.2016.01.047
  14. Kim, Y.J. and Harries, K.A. (2011), "Fatigue behavior of damaged steel beams repaired with CFRP strips", Eng. Struct., 33, 1491-1502. https://doi.org/10.1016/j.engstruct.2011.01.019
  15. Mahdi, I., Setvati, R. and Mustaffa, Z. (2018), "Rehabilitation of notched circular hollow sectional steel beam using CFRP patch", Steel Compos. Struct., Int. J., 26(2), 151-161.
  16. Photiou, N.K., Hollaway, L.C. and Chryssanthopoulos, M.K. (2006), "Strengthening of an artificially degraded steel beam utilizing a carbon/glass composite system", Construct. Build. Mater., 20,11-21. https://doi.org/10.1016/j.conbuildmat.2005.06.043
  17. Sallam, H. (2010), "Discussion of "Flexural strengthening of steel bridges with high modulus CFRP strips", (by David Schnerch and Sami Rizkalla), J. Bridge Eng., 15(1), 117-117. DOI: 10.1061/(ASCE)1084-0702(2008)13:2(192)
  18. Sallam, H., Badawy, A., Saba, A. and Mikhail, F. (2010), "Flexural behavior of strengthened steel_concrete composite beams by various plating methods", J. Constr. Steel Res., 66, 1081-1087. https://doi.org/10.1016/j.jcsr.2010.03.005
  19. Seica, M.V. and Packer, J.A. (2007), "FRP materials for the rehabilitation of tubular steel structures, for underwater applications", Compos. Struct., 80(3), 440-450. https://doi.org/10.1016/j.compstruct.2006.05.029
  20. Sen, R. and Liby, L. (1994), "Repair of steel composite bridge sections using CFRP laminates", U.S. Department of Transportation Contract B-7932, University of South Florida, Tampa, FL, USA.
  21. Sundarraja, M.C. and Prabhu, G.G. (2013), "Flexural behaviour of CFST members strengthened using CFRP composites", Steel Compos. Struct., Int. J., 15(6), 623-643. https://doi.org/10.12989/scs.2013.15.6.623
  22. Tavakkolizadeh, M. and Saadatmanesh, H. (2003), "Repair of damaged steel-concrete composite girders using carbon fiberreinforced polymer sheets", J. Compos. Constr., 7, 311-322. https://doi.org/10.1061/(ASCE)1090-0268(2003)7:4(311)
  23. Teng, J.G. and Hu, Y.M. (2007), "Behaviour of FRP-jacketed circular steel tubes and cylindrical shells under axial compression", Constr. Build. Mater., 21(4), 827-838. https://doi.org/10.1016/j.conbuildmat.2006.06.016
  24. Teng, J.G., Fernando, D. and Yu, T. (2015), "Finite element modelling of debonding failures in steel beams flexurally strengthened with CFRP laminates", Eng. Struct., 86, 213-224. https://doi.org/10.1016/j.engstruct.2015.01.003
  25. Yang, Y.X., Yue, Q.R. and Peng, F.M. (2005), "Experimental research on bond behavior of CFRP to steel", Proceedings of the International Symposium on Bond Behaviour of FRP in Structures, pp. 419-422.
  26. Yousefi, O., Narmashiri, K. and Ghaemdoust, M.R. (2017), "Structural behaviors of notched steel beams strengthened using CFRP strips", Steel Compos. Struct., Int. J., 25(1), 35-43.
  27. Zhao, X.L. and Zhang, L. (2007), "State-of-the-art review on FRP strengthened steel structures", Eng. Struct., 29, 1808-1823. https://doi.org/10.1016/j.engstruct.2006.10.006
  28. Zhong, T. and Han, L.H. (2007), "Behaviour of fire-exposed concrete-filled steel tubular beam columns repaired with CFRP wraps", Thin-Wall. Struct., 45, 63-76. https://doi.org/10.1016/j.tws.2006.11.004
  29. Zhong, T., Han, L.H. and Wang, L.L. (2007), "Compressive and flexural behaviour of CFRP-repaired concrete-filled steel tubes after exposure to fire", J. Constr. Steel Res., 63, 1116-1126. https://doi.org/10.1016/j.jcsr.2006.09.007

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