Bend Strength of Complete Closed-Type Carbon Fiber-Reinforced Polymer Stirrups with Rectangular Section
Publication: Journal of Composites for Construction
Volume 18, Issue 1
Abstract
Complete closed-type carbon fiber-reinforced polymer stirrups with a rectangular section (CFRPRS) were developed and tested in the research reported in this paper. The use of a CFRPRS is intended to relieve stress concentrations and reduce the number of kinked fibers at the bent portion. A total of 16 B.5 specimens were tested with consideration of the bend strength of the CFRPRS as well as carbon fiber-reinforced polymer (CFRP) stirrups with circular sections. Observations were made regarding the bend strength and failure modes. Three different types of CFRPRS were tested with different width-thickness ratios (34.4 for a sectional area of and 4.5 or 8.0 for ) and three different ratios of the bend radius to the area-equivalent bar diameter (1.5, 3.0, and 4.5). The test results indicated that CFRPRSs exhibited improved bend strength as compared to its counterpart, the conventional CFRP stirrups with circular sections. CFRPRSs possessing a larger stirrup width-thickness ratio provided more strength for a given sectional area. The best correlation between the test results and predictions of the CFRPRS bend strength was observed when sections of the CFRPRS were modeled as a collection of transformed individual circular sections.
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Acknowledgments
The research reported in this paper was supported by the Chung-Ang University Excellent Student Scholarship and Basic Science Research Program through the National Research Foundation of Korea (NRF), itself funded by the Ministry of Education, Science, and Technology (2010-0011490).
References
American Concrete Institute (ACI). (2004). “Guide test method for fiber reinforced polymers (FRPs) for reinforcing or strengthening concrete structures.”, Farmington Hills, MI.
American Concrete Institute (ACI). (2006). “Guide for the design and construction of concrete reinforced with FRP bar.” Farmington Hills, MI.
American Concrete Institute (ACI). (2008a). “Specification for carbon and glass fiber-reinforced polymer bar materials for concrete reinforcement.”, Farmington Hills, MI.
American Concrete Institute (ACI). (2008b). “Specification for construction with fiber-reinforced polymer reinforcing bars.”, Farmington Hills, MI.
Ahmed, E. A., El-Sayed, A. K., El-Salakawy, E., and Benmokrane, B. (2010). “Bend strength of FRP stirrups: Comparison and evaluation of testing method.” J. Compos. Constr., 3–10.
Canadian Standard Association (CSA). (2006). “Canadian highway bridge design code.” CAN/CSA S6-06, Rexdale, ON, Canada.
Ehsani, M. R., Saadatmanesh, H., and Tao, S. (1995). “Bond of hooked glass fiber reinforced plastic (GFRP) reinforcing bars to concrete.” ACI Mater. J., 92(4), 391–400.
El-Sayed, A. K., El-Salakawy, E., and Benmokrane, B. (2007). “Mechanical and structural characterization of new carbon FRP stirrups for concrete members.” J. Compos. Constr., 352–362.
Ishihara, K., Obara, T., Sato, Y., Ueda, T., and Kakuta, Y. (1997). “Evaluation of ultimate strength of FRP rods at bent-up portion.” Proc., Int. Symp. on Nonmetallic (FRP) Reinforcement for Concrete Structures, Japan Concrete Institute, Tokyo, Vol. 2, 27–34.
Intelligent Sensing for Innovative Structures (ISIS) Canada. (2006). “Specifications for product certification on fibre reinforced polymers (FRPs) as internal reinforcement in concrete structures.” Product certification of FRP materials, Univ. of Manitoba, Winnipeg, MB, Canada.
Intelligent Sensing for Innovative Structures (ISIS) Canada. (2007). “Reinforcing concrete structures with fiber reinforced polymers.”, Univ. of Winnipeg, Winnipeg, MB, Canada.
Japan Society of Civil Engineers (JSCE). (1997). “Recommendation for design and construction of concrete structures using continuous fiber reinforcing materials.” Concrete engineering series 23, A. Machida, ed., Tokyo.
Maruyama, T., Honama, M., and Okmura, H. (1993). “Experimental study on tensile strength of bent portion of FRP rods.” Special publication 138, American Concrete Institute, Farmington Hills, MI, 163–176.
Morphy, R. D. (1999). “Behaviour of fiber reinforced polymer (FRP) stirrups as shear reinforcement for concrete structures.” M.S. thesis, Univ. of Manitoba, Winnipeg, MB, Canada.
Nagasaka, T., Fukuyama, H., and Tanigaki, M. (1993). “Shear performance of concrete beams reinforced with FRP stirrups.” Special publication 138, American Concrete Institute, Farmington Hills, MI, 789–811.
Razaqpur, A. G., and Isgor, O. B. (2006). “Proposed shear design method for FRP-reinforced concrete members without stirrups.” ACI Struct. J., 103(1), 93–102.
Shehata, E., Morphy, R., and Rizkalla, S. (1998). “Use of FRP as shear reinforcement for concrete structures.” Proc., Int. Conf. on Composites in Infrastructure, Intelligent Sensing for Innovative Structures Canada, Univ. of Manitoba, Winnipeg, MB, Canada, Vol. 1, 300–314.
Shehata, E., Morphy, R., and Rizkalla, S. (2000). “Fiber reinforced polymer shear reinforcement for concrete members: Behavior and design guidelines.” Can. J. Civ. Eng., 27(5), 859–872.
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Published In
Journal of Composites for Construction
Volume 18 • Issue 1 • February 2014
Copyright
© 2013 American Society of Civil Engineers.
History
Received: Apr 19, 2013
Accepted: Jul 25, 2013
Published online: Jul 27, 2013
Published in print: Feb 1, 2014
Discussion open until: Mar 3, 2014
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