Seismic Behavior of RC Columns with Bond-Critical Regions: Criteria for Bond Strengthening Using External FRP Jackets
Publication: Journal of Composites for Construction
Volume 12, Issue 1
Abstract
In 2003, an experimental research program was initiated at the American University of Beirut with the objectives of (1) evaluating the effectiveness of external fiber-reinforced polymer (FRP) confinement in improving the bond strength of spliced reinforcement in reinforced-concrete (RC) columns and its implications on the lateral load capacity and ductility of the columns under seismic loading; and (2) establishing rational design criteria for bond strengthening of spliced reinforcement using external FRP jackets. This paper presents a discussion of recent experimental results dealing with rectangular columns and the results of a pilot study conducted on circular columns with particular emphasis on aspects related to the bond strength of the spliced column reinforcement. A nonlinear analysis model is developed for predicting the envelope load–drift response, taking into account the effect of FRP confinement on the stress–strain behavior of concrete in compression. Results predicted by the model showed excellent agreement with the test results. Design expressions of the bond strength of spliced bars in FRP-confined concrete were assessed against the current experimental data, and a criterion for seismic FRP strengthening of bond-critical regions in RC members is proposed.
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Acknowledgments
This research was supported by the Lebanese National Council for Scientific Research under Grant No. DDF 688306. The writer is most grateful for this support and to the Faculty of Engineering and Architecture at the American University of Beirut (AUB) for providing the test facilities.
References
American Concrete Institute (ACI). (2002a). “Building code requirements for reinforced concrete and commentary (ACI 318-2002/ACI 318R-02).” ACI Committee 318, ACI, Farmington Hills, Mich.
American Concrete Institute (ACI). (2002b). “Guide for the design and construction of externally bonded FRP systems for strengthening concrete structures.” ACI 440.2R-02, ACI Committee 440, ACI, Detroit.
Dagher, F. H., and Harajli, M. H. (2007). “Seismic strengthening of bond-critical regions in rectangular RC columns using external FRP jackets.” Research Rep., Dept. of civil Engineering, American Univ. of Beirut, 87.
Darwin, D., Lutz, L. A., and Zuo, J. (2005). “Recommended provisions and commentary on development and lap splice lengths for deformed reinforcing bars in tension.” ACI Struct. J., 102(6), 892–900.
Harajli, M. H. (2005). “Bond strengthening of steel bars using external FRP confinement: Implications on the static and cyclic response of RC members.” ACI Special Publication SP230, American Concrete Institute, Farmington Hills, Mich., 579–596.
Harajli, M. H., Hamad, B. H., and Rteil, A. (2004). “Effect of confinement on bond strength between steel bars and concrete.” ACI Struct. J., 101(5), 595–603.
Harajli, M. H., Hantouche, E., and Soudki, K. (2006). “Stress–strain model for fiber-reinforced polymer jacketed concrete columns.” ACI Struct. J., 103(5), 672–682.
Innovation Task Group 1 and Collaborators (Innovation Task Group). (1999) “Acceptance criteria for moment frames based on structural testing.” ACI ITG/T1.1-99, American Concrete Institute, Farmington Hills, Mich.
Lam, L., and Teng, J. G. (2003). “Design-oriented stress–strain model for FRP-confined concrete in rectangular columns.” J. Reinf. Plast. Compos., 22(13), 1149–1186.
Mander, J. B., Priestly, M. J. N., and Park, R. (1988). “Theoretical stress–strain model for confined concrete.” J. Struct. Eng., 114(8), 1804–1826.
Orangun, C. O., Jirsa, J. O., and Breen, J. E. (1975). “Strength of anchored bars: A reevaluation of test data on development length and splices.” Research Rep. No. 154-3F1975, Center for Highway Research, Univ. of Texas at Austin, Austin, Tex.
Priestly, M. J. N., Seible, F., and Calvi, G. M. (1996). Seismic design and retrofit of bridges, Wiley, New York.
Scott, B. D., Park, R., and Priestly, M. J. N. (1982). “Stress–strain behavior of concrete confined by overlapping hoops at low and high strain rates.” ACI J., 79(1), 13–27.
Seible, F., Priestly, M. J. N., Hegemier, G. A., and Innamorato, D. (1997). “Seismic retrofit of RC columns with continuous carbon fiber jackets.” J. Compos. Constr., 1(2), 52–62.
Sheikh, S. A., and Uzumeri, S. M. (1980). “Strength and ductility of tied concrete columns.” J. Struct. Div., 106(5), 1079–1102.
Information & Authors
Information
Published In
Journal of Composites for Construction
Volume 12 • Issue 1 • February 2008
Pages: 69 - 79
Copyright
© 2008 ASCE.
History
Received: Sep 25, 2006
Accepted: Jan 17, 2007
Published online: Feb 1, 2008
Published in print: Feb 2008
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