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Low strength concrete members externally confined with FRP sheets

  • Ilki, Alper (Istanbul Technical University, Civil Engineering Faculty) ;
  • Kumbasar, Nahit (Istanbul Technical University, Civil Engineering Faculty) ;
  • Koc, Volkan (Istanbul Technical University, Civil Engineering Faculty)
  • Received : 2003.09.15
  • Accepted : 2004.03.08
  • Published : 2004.08.25

Abstract

In this paper axial loading tests on low strength concrete members, which were confined with various thickness of carbon fiber reinforced polymer (CFRP) composite sheets are described. Totally 46 specimens with circular, square and rectangular cross-sections with unconfined concrete compressive strengths between 6 and 10 MPa were included in the test program. During the tests, a photogrammetrical deformation measurement technique was also used, as well as conventional measurement techniques. The contribution of external confinement with CFRP composite sheets to the compressive behavior of the specimens with low strength concrete is evaluated quantitatively, in terms of strength, longitudinal and lateral deformability and energy dissipation. The effects of width/depth ratios and the corner radius of the specimens with rectangular cross-section on the axial behavior were also examined. It was seen that the effectiveness of the external confinement with CFRP composite sheets is much more pronounced, when the unconfined concrete compressive strength is relatively lower. It was also found that the available analytical expressions proposed for normal or high strength concrete confined by CFRP sheets could not predict the strength and deformability of CFRP confined low strength concrete accurately. New expressions are proposed for the compressive strength and the ultimate axial strain of CFRP confined low strength concrete.

Keywords

References

  1. Ahmad, S.H. and Shah, S.P. (1985), "Behavior of hoop confined concrete under high strain rates", J. the American Concrete Institute, 82, 634-647.
  2. American Concrete Institute (2002), "Guide for the design and construction of externally bonded FRP systems for strengthening concrete structures", ACI Committee 440, Technical Committee Document 440.2R-02.
  3. Becque, J., Patnaik, A.K. and Rizkalla, S.H. (2003), "Analytical models for concrete confined with FRP tubes", J. Compos. Const., 7(1), 31-38. https://doi.org/10.1061/(ASCE)1090-0268(2003)7:1(31)
  4. Campione, G. and Miraglia, N. (2003), "Strength and strain capacities of concrete compression members reinforced with FRP", Cement & Concrete Composites, 25, 31-41. https://doi.org/10.1016/S0958-9465(01)00048-8
  5. Chaallal, O., Shahawy, M. and Hassan, M. (2003), "Performance of axially loaded short rectangular columns strengthened with carbon fiber-reinforced polymer wrapping", J. Compos. Const., 7(3), 200-208. https://doi.org/10.1061/(ASCE)1090-0268(2003)7:3(200)
  6. De Lorenzis, L. and Tepfers, R. (2003), "Comparative study of models on confinement of concrete cylinders with fiber-reinforced polymer composites", J. Compos. Const., 7(3), 219-237. https://doi.org/10.1061/(ASCE)1090-0268(2003)7:3(219)
  7. Demers, M. and Neale, K.W. (1994), "Strengthening of concrete columns with unidirectional composite sheets", Development in Short and Medium Span Bridge Engineering '94, Proc., 4th Int. Conf. on Short and Medium Bridges, A.A. Mufti, B. Bakht, and L.G. Jaeger, eds., Canadian Society for Civil Engineering, Montreal, 895- 905.
  8. Demers, M. and Neale, K.W. (1999), "Confinement of reinforced concrete columns with fibre-reinforced composite sheets-an experimental study", Can. J. Civ. Eng., 26(2), 226-241. https://doi.org/10.1139/cjce-26-2-226
  9. Fam, A.Z. and Rizkalla, S.H. (2001), "Confinement model for axially loaded concrete confined by circular fiberreinforced polymer tubes", ACI Struct. J., 98(4), 451-461.
  10. Fardis, M.N. and Khalili, H. (1982), "FRP-encased concrete as a structural material", Magazine of Concrete Research, 34(121), 191-202. https://doi.org/10.1680/macr.1982.34.121.191
  11. Fukuyama, H. and Sugano, S. (2000), "Japanese seismic rehabilitation of concrete buildings after the Hyogoken- Nanbu earthquake", Cement & Concrete Composites, 22, 59-79. https://doi.org/10.1016/S0958-9465(99)00042-6
  12. Fyfe, E.R. (1996), "Column seismic retrofitting using high-strength fiber jackets", Seismic Rehabilitation of Concrete Structures, ACI SP-160, 161-168.
  13. Guadagnini, M., Pilakoutas, K. and Waldron, P. (2001), "An overview of the European research on FRPs and their applications", Proc. of Int. Conf. on FRP Composites in Civil Engineering, Hong Kong, 1699-1706.
  14. Harmon, T.G. and Slattery, K.T. (1992), "Advanced composite confinement of concrete", Proc., 1st Int. Conf. on Advanced Composite Materials in Bridges and Structures, K.W. Neale and P. Labossiere, eds., Canadian Society for Civil Engineering, Sherbrooke, Canada, 299-306.
  15. Hoshikuma, J., Kawashima, K., Nagaya, K. and Taylor, A.W. (1997), "Stress-strain model for confined reinforced concrete in bridge piers", J. Struct. Eng., ASCE, 123(5), 624-633. https://doi.org/10.1061/(ASCE)0733-9445(1997)123:5(624)
  16. Igarashi, S. (1999), "Recommendations on minimizing earthquake damage in big cities in Turkey", Proc., Int. Conf. on the Kocaeli Earthquake, Istanbul, Turkey, 271-286.
  17. Ilki, A., Ozdemir, P. and Fukuta, T. (1997), Confinement Effect of Reinforced Concrete Columns with Circular Cross-Section, BRI Research Paper, 143, Building Research Institute, Tsukuba.
  18. Ilki, A. and Kumbasar, N. (2002), "Behavior of damaged and undamaged concrete strengthened by carbon fiber composite sheets", Struct. Eng. Mech., 13(1), 75-90. https://doi.org/10.12989/sem.2002.13.1.075
  19. Ilki, A. and Kumbasar, N. (2003), "Compressive behaviour of carbon fibre composite jacketed concrete with circular and non-circular cross-sections", J. Earthq. Eng., 7(3), 381-406. https://doi.org/10.1142/S1363246903001140
  20. Karbhari, V.M. and Gao, Y. (1997), "Composite jacketed concrete under uniaxial compression-verification of simple design equations", J. Materials in Civil Engineering, ASCE, 9(4), 185-193. https://doi.org/10.1061/(ASCE)0899-1561(1997)9:4(185)
  21. Kent, D.C. and Park, R. (1971), "Flexural members with confined concrete", J. Struct. Div., ASCE, 97(ST7), 1969-1990.
  22. Lam, L. and Teng, J.G. (2002), "Strength models for fiber-reinforced plastic-confined concrete", J. Struct. Eng., ASCE, 128(5), 612-623. https://doi.org/10.1061/(ASCE)0733-9445(2002)128:5(612)
  23. Lam, L. and Teng, J.G. (2003a), "Design-oriented stress-strain model for FRP-confined concrete", Construction and Building Materials, 17, 471-489. https://doi.org/10.1016/S0950-0618(03)00045-X
  24. Lam, L. and Teng, J.G. (2003b), "Design-oriented stress-strain model for FRP-confined concrete in rectangular columns", Journal of Reinforced Plastics and Composites, 22(13), 1149-1186. https://doi.org/10.1177/0731684403035429
  25. Maalej, M., Tanwongsval, S. and Paramasivam, P. (2003), "Modelling of rectangular RC columns strengthened with FRP", Cement & Concrete Composites, 25, 263-276. https://doi.org/10.1016/S0958-9465(02)00017-3
  26. Mander, J.B., Priestley, M.J.N. and Park, R. (1988a), "Observed stress-strain behaviour of confined concrete", J. Struct. Div., ASCE, 114(8), 1827-1849. https://doi.org/10.1061/(ASCE)0733-9445(1988)114:8(1827)
  27. Mander, J.B., Priestley, M.J.N. and Park, R. (1988b), "Theoretical stress-strain model for confined concrete", J. Struct. Div., ASCE, 114(8), 1804-1826. https://doi.org/10.1061/(ASCE)0733-9445(1988)114:8(1804)
  28. Mbrace Product Catalogues, (2000), YKS Construction Chemicals, Turkey.
  29. Mirmiran, A. and Shahawy, M. (1997), "Behavior of concrete columns confined by fiber composites", J. Struct. Eng., ASCE, 123(5), 583-590. https://doi.org/10.1061/(ASCE)0733-9445(1997)123:5(583)
  30. Mirmiran, A., Shahawy, M., Samaan, M., El Echary, H., Mastrapa, J.C. and Pico, O. (1998), "Effect of column parameters on FRP-confined concrete", J. Comp. Const., ASCE, 2(4), 175-185. https://doi.org/10.1061/(ASCE)1090-0268(1998)2:4(175)
  31. Mugurama, H. and Watanabe, F. (1990), "Ductility improvement of high-strength concrete columns with lateral confinement", in ACI Spec. Publ., SP-121-4, Am. Conc. Inst., Detroit, Mich., 47-60.
  32. Mugurama, H., Watanabe, F., Iwashimizu, T. and Mitsueda, R. (1983), "Ductility improvement of high strength concrete by lateral confinement", Transactions of Japan Concrete Institute, 5, 403-410.
  33. Nanni, A. and Bradford, N.M. (1995), "FRP jacketed concrete under uniaxial compression", Constr. Build. Mater., 9(2), 115-124. https://doi.org/10.1016/0950-0618(95)00004-Y
  34. Park, R., Priestley, M.J.N. and Gill, W.D. (1982), "Ductility of square-confined concrete columns", J. Struct. Div., ASCE, 108(ST4), 929-950.
  35. Priestley, M.J.N., Park, R. and Potangaroa, R.T. (1981), "Ductility of spirally confined columns", J. Struct. Div., ASCE, 107(ST1), 181-202.
  36. Richard, R.M. and Abbot, B.J. (1975), "Versatile elastic-plastic stress-strain formula", J. Eng. Mech., ASCE, 101(4), 511-515.
  37. Rochette, P. and Labossiere, P. (2000), "Axial testing of rectangular column models confined with composites", J. Comp. Const., ASCE, 4(3), 129-136. https://doi.org/10.1061/(ASCE)1090-0268(2000)4:3(129)
  38. Saadatmanesh, H., Ehsani, M.R. and Li, M.W. (1994), "Strength and ductility of concrete columns externally reinforced with fiber composite straps", ACI Struct. J., 91(4), 434-447.
  39. Saafi, M., Toutanji, H. and Li, Z. (1999), "Behavior of concrete columns confined with fiber reinforced polymer tubes", ACI Materials J., 96(4), 500-509.
  40. Saatcioglu, M. and Razvi, S.R. (1992), "Strength and ductility of confined concrete", J. Struct. Div., ASCE, 118(6), 1590-1607. https://doi.org/10.1061/(ASCE)0733-9445(1992)118:6(1590)
  41. Saatcioglu, M., Salamat, A.H. and Razvi, S.R. (1995), "Confined columns under eccentric loading", J. Struct. Eng., ASCE, 121(11), 1547-1556. https://doi.org/10.1061/(ASCE)0733-9445(1995)121:11(1547)
  42. Samaan, M., Mirmiran, A. and Shahawy, M. (1998), "Model of concrete confined by fiber composites", J. Struct. Eng., ASCE, 124(9), 1025-1031. https://doi.org/10.1061/(ASCE)0733-9445(1998)124:9(1025)
  43. Sheikh, S.A. and Uzumeri, S.M. (1982), "Analytical model for concrete confinement in tied columns", J. Struct. Div., ASCE, 108(ST12), 2703-2722.
  44. Spoelstra, M.R. and Monti, G. (1999), "FRP-confined concrete model", J. Compos. Const., 3(3), 143-150. https://doi.org/10.1061/(ASCE)1090-0268(1999)3:3(143)
  45. Tan, K.H. (2002), "Strength enhancement of rectangular reinforced concrete columns using fiber-reinforced polymer", J. Compos. Const., 6(3), 175-183. https://doi.org/10.1061/(ASCE)1090-0268(2002)6:3(175)
  46. Teng, J.G. and Lam, L. (2002), "Compressive behavior of carbon fiber reinforced polymer-confined concrete in elliptical columns", J. Struct. Eng., 128(12), 1535-1543. https://doi.org/10.1061/(ASCE)0733-9445(2002)128:12(1535)
  47. Toutanji, H.A. (1999), "Stress - strain characteristics of concrete columns externally confined with advanced fiber composite sheets", ACI Materials J., 96(3), 397-404.
  48. Wang, Y.C., Restrepo, J.I. and Park, R. (2000), "Retrofit of reinforced concrete members using advanced composite materials", Research Report 2000-3, Department of Civil Engineering, University of Canterbury, New Zealand.
  49. Wang, Y.C. and Restrepo, J.I. (2001), "Investigation of concentrically loaded reinforced concrete columns confined with glass fiber-reinforced polymer jackets", ACI Struct. J., 98(3), 377-385.
  50. Xiao, Y. and Wu, H. (2000), "Compressive behaviour of concrete confined by carbon fiber composite jackets", J. Materials Civil Eng., ASCE, 12(2), 139-146. https://doi.org/10.1061/(ASCE)0899-1561(2000)12:2(139)

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