Strengthening RC Beams in Flexure Using New Hybrid FRP Sheet/Ductile Anchor System
Publication: Journal of Composites for Construction
Volume 13, Issue 3
Abstract
This paper explores a new hybrid fiber-reinforced polymer (FRP) sheet/ductile anchor system for rehabilitation of reinforced concrete (RC) beams. The advantages of the proposed strengthening method is that it overcomes the problem of low ductility that is associated with brittle failure mode in conventional methods of strengthening beams using epoxy-bonded FRP sheets. The proposed system leads to a ductile failure mode by triggering yielding to occur in a steel anchor system (steel links) rather than by rupture or debonding of FRP sheets, which is sudden in nature. Four half-scale RC -beams were tested under four-point bending. Three retrofitted beams were strengthened using one layer of carbon FRP sheet. The results of the two beams that were strengthened with the new hybrid FRP sheet/ductile anchor system were compared with the results from the beam strengthened with conventional FRP bonding method and the control beam. The results show the effectiveness of the proposed strengthening system in increasing flexural capacity and ductility of RC beams.
Get full access to this article
View all available purchase options and get full access to this article.
Acknowledgments
The writers gratefully acknowledge the support of Natural Sciences and Engineering Research Council of Canada (NSERC)NSERC, le Fonds Québécois de la Recherche sur la Nature et les Technologies (FQRNT), and Fyfe Co.
References
ACI. (2002). “Design and construction of externally bonded FRP systems for strengthening concrete structures.” 440.2R-02, ACI Committee, 440, American Concrete Institute, Farmington Hills, Mich.
Bencardino, F., Spadea, G., and Swamy, R. (2002). “Strength and ductility of reinforced concrete beams externally reinforced with carbon fibre fabric.” ACI Struct. J., 99(3), 163–171.
Blaschko, M., and Zilch, K. (1999). “Rehabilitation of concrete structures with strips glued into slits.” Proc., 12th Int. Conf. on Composite Materials (CD-ROM).
Borowicz, D. T. (2002). “Rapid strengthening of concrete beams with powder-actuated fastening systems and fiber reinforced polymer (FRP) composite materials.” MS thesis, Dept. of Civil Engineering, Univ. of Wisconsin-Madison, Madison, Wis.
Canadian Highway Bridge Design Code. (2006). CAN/CSA-S6–06, Canadian Standards Association, Mississauga, Canada.
CSA. (2004). “Design of concrete structures.” A23.3-04, Canadian Standards Association, Ontario, Canada.
De Lorenzis, L., and Nanni, A. (2001). “Shear strengthening of reinforced concrete beams with near-surface mounted fibre reinforced polymer rods.” ACI Struct. J., 98(1), 60–68.
Dussek, I. J. (1980). “Strengthening of bridge beams and similar structures by means of epoxy-resin-bonded external reinforcement.” Transportation Research Record. 785, Transportation Research Board, Washington, D.C., 21–24.
El Maaddawy, T., Hamelin, J., Hrynyk, T., Schaus, L., and Soudki, K. (2005). “Strengthening of one way reinforced concrete slabs with mechanically anchored unbonded FRP strips.” Proc., 33rd Annual General Conf. of the Canadian Society for Civil Engineering (CD-ROM), GC-214, 1–7.
Fanning, P. J., and Kelly, O. (2001). “Ultimate response of RC beams strengthened with CFRP plates.” J. Compos. Constr., 5(2), 122–127.
Fib. (2001). “Design and use of externally bonded FRP reinforcement (FRP EBR) for reinforced concrete structures.” Progress Rep. of fib EBR Group, Int. Concrete Federation.
Fyfe. (2007). “Tyfo® SCH-11UP composite using Tyfo® S epoxy user’s guide.” Fyfe Company LLC, ⟨http://www.fyfeco.com⟩ (Jan. 2007).
Hassan, T., and Rizkalla, S. (2003). “Investigation of bond in concrete structures strengthened with near surface mounted carbon fiber reinforced polymer strips.” J. Compos. Constr., 7(3), 248–257.
Hilti. (2007). “HSL heavy duty sleeve anchor.” Hilti (Canada) Corp., ⟨http://www.ca.hilti.com⟩ (Sept. 2007).
ISIS Canada. (2006). “An introduction to FRP strengthening of concrete structures.” ISIS educational module 4, Queen’s Univ.
Klaiber, F. W., Dunker, K. F., Wipf, T. J., and Sanders, W. W., Jr. (1987). “Methods of strengthening existing highway bridges.” NCHRP Research Rep. No. 293, Transportation Research Report Board.
Lamanna, A., Bank, L., and Scott, D. (2001). “Flexural strengthening of reinforced concrete beams using fasteners and fiber-reinforced polymer strips.” ACI Struct. J., 98(3), 368–376.
Manos, G. C., Katakalos, K., Kourtides, V., and Mitsarakis, C. (2007). “Upgrading the flexural capacity of a vertical R/C member using carbon fiber reinforcing plastics applied externally and anchored at the foundation.” Proc., AFRPRCS-8 Symp. 2007 (CD-ROM).
Meier, U. (1992). “Carbon fibre-reinforced polymers: Modern materials in bridge engineering.” Struct. Eng. Int. (IABSE, Zurich, Switzerland), 2, 7–12.
Mirza, S. M., and Haider, M. (2003). “The state of infrastructure in Canada: Implications for infrastructure planning and policy.” Study prepared for infrastructure Canada.
Nanni, A. (1995). “Concrete repair with externally bonded FRP reinforcement,” Concr. Int., (17)6, 22–26.
Quattlebaum, J. B., Harries, K. A., and Petrou, M. F. (2005). “Comparison of three flexural retrofit systems under monotonic and fatigue loads.” J. Bridge Eng., 10(6), 731–740.
Ritchie, P. A., Thomas, D. A., Lu, L. W., and Connelly, G. M. (1991). “External reinforcement of concrete beams using fiber reinforced plastics.” ACI Struct. J., 88(4), 490–500.
Saadatmanesh, E., and Ehsani, M. R. (1989). “Application of fibre composites in civil engineering.” Proc., 7th ASCE Structures Congress, ASCE, New York, 526–535.
Sharif, A., Al-Sulimani, G. J., Basunbul, I. A., Baluch, M. H., and Ghaleb, B. N. (1994). “Strengthening of initially loaded reinforced concrete beams using FRP plates.” ACI Struct. J., 91(2), 160–168.
Swamy, R. N., and Mukhopadhyaya, P. (1999). “Debonding of carbon fibre reinforced polymer plate from concrete beams.” Proc. Inst. Civ. Eng., Struct. Build., 134(4), 301–317.
Information & Authors
Information
Published In
Journal of Composites for Construction
Volume 13 • Issue 3 • June 2009
Pages: 217 - 225
Copyright
© 2009 ASCE.
History
Received: May 29, 2008
Accepted: Dec 4, 2008
Published online: Mar 21, 2009
Published in print: Jun 2009
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.