Effect of GFRP Reinforcement Ratio on the Strength and Effective Stiffness of High-Strength Concrete Columns: Experimental and Analytical Study
Publication: Journal of Composites for Construction
Volume 24, Issue 5
Abstract
This paper reports the axial–flexural test results for 12 high-strength concrete (HSC) columns reinforced with glass fiber-reinforced polymer (GFRP) rebars to evaluate the implication of using HSC. The parameters were the applied eccentricity, the longitudinal GFRP reinforcement ratio, and concrete compressive strength and investigate their influence on the load-carrying capacity, deflection, ductility, strains in the concrete and reinforcement, failure modes, and flexural stiffness. All the columns failed in a compression failure mode due to concrete crushing. The GFRP bars developed higher tensile strains in the HSC due to the axial–flexural load compared to columns made with normal-strength concrete (NSC). A minimum reinforcement ratio of 1% in the case of HSC proved practical. Increasing the reinforcement ratio to 2.5% improved the postpeak behavior and yielded a second peak for specimens tested at eccentricities corresponding to 30%, 40%, and 60% of the cross-sectional depth. This study integrated the results to develop an analytical model able to establish moment–curvature and effective-stiffness relationships. The results were also evaluated for the tested specimens and compared to the theoretical expressions used for NSC.
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Acknowledgments
The authors would like to express their special thanks and gratitude to the Natural Science and Engineering Research Council of Canada (NSERC), the NSERC Industrial Research Chair in FRP Reinforcement for Concrete Infrastructure, the Tier-1 Canada Research Chair in Composite Materials for Civil Structures, and the Fonds de la recherche du Quebec-Nature et Technologie (FRQ-NT) for their financial support. The authors would like to thank TUF-BAR Canada for providing the GFRP reinforcement and the technical staff of the Structural and Materials Lab in the Department of Civil Engineering at the University of Sherbrooke.
References
ACI (American Concrete Institute). 2010. Report on high-strength concrete. ACI 363R-10. Farmington Hills, MI: ACI.
ACI (American Concrete Institute). 2015. Guide for the design and construction of concrete reinforced with FRP bars. ACI 440.1R-15. Farmington Hills, MI: ACI.
ACI (American Concrete Institute). 2019. Building code requirements for structural concrete. ACI 318-14M. Farmington Hills, MI: ACI.
Afifi, M. Z., H. M. Mohamed, and B. Benmokrane. 2014. “Axial capacity of circular concrete columns reinforced with GFRP bars and spirals.” J. Compos. Constr. 18 (1): 04013017. https://doi.org/10.1061/(ASCE)CC.1943-5614.0000438.
ASTM. 2011. Standard test method for tensile properties of fiber reinforced polymer matrix composite bars. ASTM D7205-11. West Conshohocken, PA: ASTM.
Choo, C. C., I. E. Harik, and H. Gesund. 2006a. “Minimum reinforcement ratio for fiber-reinforced polymer reinforced concrete rectangular columns.” ACI Struct. J. 103 (3): 460–466.
Choo, C. C., I. E. Harik, and H. Gesund. 2006b. “Strength of rectangular concrete columns reinforced with fiber-reinforced polymer bars.” ACI Struct. J. 103 (3): 452–459.
CSA (Canadian Standards Association). 2010. Specification for fibre reinforced polymers. CSA S807-10. Mississauga, Ontario, Canada: CSA.
CSA (Canadian Standards Association). 2012. Design and construction of building structures with fibre reinforced polymers. CAN/CSA S806-12. Rexdale, Ontario, Canada: CSA.
De Luca, A., F. Matta, and A. Nanni. 2009. “Behavior of full-scale glass fiber-reinforced polymer reinforced concrete columns under axial load.” ACI Struct. J. 107 (5): 589–596.
El-Nemr, A., E. A. Ahmed, and B. Benmokrane. 2013. “Flexural behavior and serviceability of normal- and high-strength concrete beams reinforced with glass fiber-reinforced polymer bars.” ACI Struct. J. 110 (6): 1077–1087.
Guérin, M., H. M. Mohamed, B. Benmokrane, A. Nanni, and C. K. Shield. 2018a. “Eccentric behavior of full-scale reinforced concrete columns with glass fiber-reinforced polymer bars and ties.” ACI Struct. J. 115 (2): 489–500. https://doi.org/10.14359/51701107.
Guérin, M., H. M. Mohamed, B. Benmokrane, C. K. Shield, and A. Nanni. 2018b. “Effect of glass fiber-reinforced polymer reinforcement ratio on the axial–flexural strength of reinforced concrete columns.” ACI Struct. J. 115 (4): 1049–1061. https://doi.org/10.14359/51701279.
Hadhood, A., H. M. Mohamed, and B. Benmokrane. 2017a. “Strength of circular HSC columns reinforced internally with carbon–fiber-reinforced polymer bars under axial and eccentric loads.” Constr. Build. Mater. 141: 366–378. https://doi.org/10.1016/j.conbuildmat.2017.02.117.
Hadhood, A., H. M. Mohamed, and B. Benmokrane. 2017b. “Failure envelope of circular concrete columns reinforced with GFRP bars and spirals.” ACI Struct. J. 114 (6): 1417–1428. https://doi.org/10.14359/51689498.
Hadhood, A., H. M. Mohamed, and B. Benmokrane. 2018. “Flexural stiffness of GFRP- and CFRP-RC circular members under eccentric loads based on experimental and curvature analysis.” ACI Struct. J. 115 (4): 1185–1198. https://doi.org/10.14359/51702235.
Hadi, M. N. S., H. A. Hassan, and M. N. Sheikh. 2017. “Experimental investigation of circular high-strength concrete columns reinforced with glass fiber-reinforced polymer bars and helices under different loading conditions.” J. Compos. Constr. 21 (4): 04017005. https://doi.org/10.1061/(ASCE)CC.1943-5614.0000784.
Kassem, C., A. S. Farghaly, and B. Benmokrane. 2011. “Evaluation of flexural behavior and serviceability performance of concrete beams reinforced with FRP bars.” J. Compos. Constr. 15 (5): 682–695. https://doi.org/10.1061/(ASCE)CC.1943-5614.0000216.
Légeron, F., and P. Paultre. 2003. “Uniaxial confinement model for normal- and high-strength concrete columns.” J. Struct. Eng. 129 (2): 241–252. https://doi.org/10.1061/(ASCE)0733-9445(2003)129:2(241).
Naaman, A. E., and S. M. Jeong. 1995. “Structural ductility of concrete beams prestressed with FRP tendons.” In Proc., Second International RILEM Symposium (FRPRCS-2), Non-Metallic (FRP) Reinforcement for Concrete Structures, 379–386. London: E & FN Spon.
Nanni, A., A. De Luca, and H. Jawaheri Zadeh. 2014. Reinforced concrete with FRP bars: Mechanics and design. Boca Raton, FL: CRC Press.
Pantelides, C. P., M. E. Gibbons, and L. D. Reaveley. 2013. “Axial load behavior of concrete columns confined with GFRP spirals.” J. Compos. Constr. 305–313. https://doi.org/10.1061/(ASCE)CC.1943-5614.0000357.
Popovics, S. 1973. “A numerical approach to the complete stress-strain curve of concrete.” Cem. Concr. Res. 3 (5): 583–599. https://doi.org/10.1016/0008-8846(73)90096-3.
Mohamed, A. 2019. Axial–flexural performance of HSC columns reinforced with GFRP and BFRP bars and ties. Sherbrooke, Canada: Université de Sherbrooke.
Shield, C., T. Galambos, and P. Gulbrandsen. 2011. “On the history and reliability of the flexural strength of FRP reinforced concrete members in ACI 440.1R.” In Proc., 10th Int. Symp. on Fiber-Reinforced Polymer Reinforcement for Concrete Structures, edited by R. Sen, R. Seracino, C. Shield, and W. Gold. Farmington Hills, MI: American Concrete Institute.
Thorenfeldt, E., A. Tomaszewicz, and J. J. Jensen. 1987. “Mechanical properties of high strength concrete and application to design.” In Proc., Symp.: Utilization of High-Strength Concrete, 149–159. Stavanger, Norway: Tapir Trondheim.
Tobbi, H., A. S. Farghaly, and B. Benmokrane. 2014. “Behavior of concentrically loaded fiber-reinforced polymer reinforced concrete columns with varying reinforcement types and ratios.” ACI Struct. J. 111 (2): 375–385.
TUF-BAR Canada. 2017. Accessed January 15, 2016. https://www.tuf-bar.com/.
Yost, J. R., S. P. Gross, and D. W. Dinehart. 2003. “Effective moment of inertia for glass fiber-reinforced polymer-reinforced concrete beams.” ACI Struct. J. 100 (6): 732–739.
Zadeh, H. J., and A. Nanni. 2013. “Design of RC columns using glass FRP reinforcement.” J. Compos. Constr. 17 (3): 294–304. https://doi.org/10.1061/(ASCE)CC.1943-5614.0000354.
Zadeh, H. J., and A. Nanni. 2017. “Flexural stiffness and second-order effects in FRP-RC frames.” ACI Struct. J. 114 (2): 533–544. https://doi.org/10.14359/51689257.
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Published In
Journal of Composites for Construction
Volume 24 • Issue 5 • October 2020
Copyright
© 2020 American Society of Civil Engineers.
History
Received: Jun 4, 2019
Accepted: May 28, 2020
Published online: Jul 30, 2020
Published in print: Oct 1, 2020
Discussion open until: Dec 30, 2020
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