Behavior of GFRP Reinforcing Bars Subjected to Extreme Temperatures
Publication: Journal of Composites for Construction
Volume 14, Issue 4
Abstract
Corrosion of steel reinforced concrete members has stimulated the research on fiber-reinforced polymers (FRP) to be used as an internal reinforcement for concrete structures. The behavior of glass fiber-reinforced polymer (GFRP) reinforcing bars subjected to extreme temperatures is very critical for applications in North America, especially in Canada. There is a high demand for experimental studies to investigate the thermal stability of strength, along with the ultimate elongation, and modulus of GFRP bars. This paper evaluates the variation of mechanical properties of sand-coated GFRP reinforcing bars subjected to low temperatures (ranging from 0 to ) and elevated temperatures (ranging from 23 to ). Tensile, shear and flexural properties are investigated to get an overview of the thermal stability of mechanical properties of GFRP bars subjected to large variations of temperatures. Microstructural analyzes using scanning electronic microscopy (SEM), physical measurements by thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC), are also conducted to investigate the deterioration of fiber, matrix, and the fiber/matrix interface due to extreme temperatures. Increase of mechanical properties due to the matrix stiffness at lower temperatures, is also investigated. On the other hand, at very high temperatures, nearing about the glass-transition temperatures of the polymer matrix, the mechanical properties, especially the stiffness and the strength of the composites are decreased considerably.
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Acknowledgments
The writers thank the National Science and Engineering Research Council (NSERC) of Canada, the Fonds Québécois sur la Recherche en Nature et les Technologies (FQRNT), and the Canadian Network of Centres of Excellence on Intelligent SENSING for Innovative Structures (ISIS Canada) for their support for the research activity reported.UNSPECIFIED
References
American Concrete Institute (ACI). (2004). “Guide test methods for fiber reinforced polymers (FRPs) for reinforcing or strengthening concrete Structures.” ACI 440.3R-04, Farmington Hills, Mich.
ASTM. (2000). “Standard test methods for density and specific gravity (relative density) of plastics by displacement.” ASTM D792, West Conshohocken, Pa.
ASTM. (2003a). “Standard test method for compositional analysis by thermogravimetry.” ASTM E1131, West Conshohocken, Pa.
ASTM. (2003b). “Standard test method for flexural properties of fiber reinforced pultruded plastic rods.” ASTM D4476, West Conshohocken, Pa.
ASTM. (2004). “Standard test method for loss-on-drying by thermogravimetry.” ASTM E1868, West Conshohocken, Pa.
ASTM. (2007). “Standard test method for plastics: Dynamic mechanical properties: In flexure (three-point bending).” ASTM D5023, West Conshohocken, Pa.
ASTM. (2008). “Standard test method for assignment of the glass transition temperatures by differential scanning calorimetry.”ASTM E1356, West Conshohocken, Pa.
Chin, J., Haight, M. R., Hughes, W. L., and Nguyen, T. (1998). “Environmental effects on composites matrixes used in construction.” Proc., 1st Int. Conf. on Durability of Fibre Reinforced Polymer for Construction, CDCC’98, Univ. of Sherbrooke, Sherbrooke, Que., Canada, 229–241.
Chu, W., and Karbhari, V. M. (2005). “Effect of water sorption on performance of pultruded e-glass/vinylester composites.” J. Mater. Civ. Eng., 17(1), 63–71.
Dutta, P. K. (1992). “Low temperature compressive strength of glass-fibre reinforced polymercomposites.” Proc., 11th Int. Conf. on Offshore Mechanics and Arctic Engineering, ASME, New York.
Foster, S. K., and Bisby, L. A. (2008). “Fire survivability of externally bonded FRP strengthening systems.” J. Compos. Constr., 12(5), 553–561.
Haramis, J. (2003). “Freeze-thaw durability of polymeric composite materials for use in civil infrastructure.” Ph.D. dissertation, Dept. Of Civil Engineering, Virginia Polytechnic Institute and State Univ., Blacksburg, Va.
Karbhari, V. M., et al. (2003). “Durability Gap analysis for fibre-reinforced polymer composites in civil infrastructure.” J. Compos. Constr., 7(3), 238–241.
Karbhari, V. M., Rivera, J., and Dutta, P. K. (2000). “Effect of short-term freeze-thaw cycling on composite confined concrete.” J. Compos. Constr., 4(4), 191–197.
Karbhari, V. M., Rivera, J., and Zhang, J. (2002). “Low-temperature hygrothermal degradation of ambient cured E-glass/vinyl ester composites.” J. Appl. Polym. Sci., 86, 2255–2260.
Katz, A., Berman, N., and Bank, L. C. (1999). “Effect of high temperature on bond strength of FRP reinforcing bar.” J. Compos. Constr., 3(2), 73–81.
Kodur, V. K. L., and Bisby, L. A. (2005). “Evaluation of fire endurance of concrete slabs reinforced with fiber-reinforced polymer bars.” J. Struct. Eng., 131(1), 34–43.
Kodur, V. K. R., and Baingo, D. (1999). “Fire resistance of FRP reinforced concrete slabs.” Technical Rep. No. IR758, National Research Council, Ottawa, Canada.
Kodur, V. K. R., Bisby, L. A., and Green, M. F. (2007). “Guidance for the design of FRP-strengthened concrete members exposed to fire.” J. Fire Prot. Eng., 17(1), 5–26.
Kumahara, S., Masuda, Y., and Tanano, Y. (1993). “Tensile strength of continuous fiber reinforcing bar under high temperature.” Proc., Fiber-Reinforced Plastic Reinforcement For Concrete Structures, C. W. Dolan, S. H. Rizkalla, and A. Nanni, eds., American Concrete Institute, Detroit, 731–742.
Lord, H. W., and Dutta, P. K. (1988). “On the design of polymeric composite structures for cold regions applications.” J. Reinf. Plast. Compos., 7(5), 435–458.
Panigrahi, B. K. (2006). “Microstructures and properties of low-alloy fire resistant steel.” Bull. Mater. Sci., 29(1), 59–66.
Robert, M., Cousin, P., and Benmokrane, B. (2009). “Durability of GFRP reinforcing bars embedded in moist concrete.” J. Compos. Constr., 13(2), 66–73.
Sayed-Ahmed, E. Y., and Shrive, N. G. (1999). “Smart FRP prestressing tendons: Properties and prospects.” Proc., Second Middle East Symp. on Structural Composites for Infrastructure Applications, A. H. Hosny, I. Mahfouz, and S. Sarkani, eds., 80–93.
Uomoto, T. (2004). “Development of new GFRP with high alkali resistivity.” Proc., Fourth Int. Conf. on Advanced Composite Materials in Bridges and Structures, ACMBS-IV (CD-ROM), Canadian Society of Civil Engineering, Calgary, Alberta, Canada.
Wang, Y. C., Wong, P. M. H., and Kodur, V. (2007). “An experimental study of the mechanical properties of fibre reinforced polymer (FRP) and steel reinforcing bars at elevated temperatures.” Compos. Struct., 80, 131–140.
Weber, A., and Witt, C. (2008). “Composite rebars in RC members in case of fire.” Proc., Advanced Composite Materials in Bridges and Structures, Canadian Society of Civil Engineering, Winnipeg, Manitoba Canada.
Information & Authors
Information
Published In
Journal of Composites for Construction
Volume 14 • Issue 4 • August 2010
Pages: 353 - 360
Copyright
© 2010 ASCE.
History
Received: Apr 26, 2009
Accepted: Nov 11, 2009
Published online: Nov 13, 2009
Published in print: Aug 2010
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