Performance of Concrete Panels Reinforced with Carbon Fiber–Reinforced Polymer Materials
Publication: Journal of Composites for Construction
Volume 21, Issue 3
Abstract
As traffic loads increase and bridge infrastructure ages, it is becoming increasingly necessary to strengthen existing bridge members. Externally applied carbon fiber–reinforced polymer (CFRP) materials are often used to strengthen reinforced concrete structures. Four full-scale I-girder tests showed differences in the shear-strength contributions of anchored CFRP strips when they are applied in unidirectional U-wrap applications as opposed to bidirectional applications. Because the number of tests was so limited, a series of panel tests was developed to attempt to explain the role of unidirectional and bidirectional CFRP layouts. Concrete panels were constructed and tested under compressive forces generating bottle-shaped compression struts to evaluate effectiveness of CFRP strengthening. Although the results cannot be directly compared with the conditions in the web of an I-girder, they allowed consideration of a number of parameters that could not have been studied by using expensive full-scale I-girders. The effects of the inclination of CFRP strips relative to the direction of cracking, the layout of CFRP strips, and the amount of CFRP strip and anchor were studied through the panel tests. To prevent premature debonding of CFRP strips from the panel surface, CFRP anchors were used. The tests highlighted the most critical parameters that influence the effectiveness of CFRP materials in strengthening applications, especially for bidirectional CFRP layouts. Qualitative comparisons were presented on the basis of the panel tests. Bidirectional CFRP layout showed better crack control and strength gain than unidirectionally strengthened panels before unexpected CFRP anchor failure.
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Acknowledgments
The authors wish to acknowledge the support from the Texas DOT for Project 0-6783. The contents of this paper reflect the views of the authors, who are responsible for the material presented. The contents do not necessarily reflect the official view of the Texas DOT. The help of students, staff, and faculty at the Ferguson Structural Engineering Laboratory is gratefully acknowledged.
References
AASHTO. (2014). AASHTO LRFD bridge design specifications, 7th Ed., Washington, DC.
ACI (American Concrete Institute). (2008). “Guide for the design and construction of externally bonded FRP systems for strengthening concrete structures.”, Farmington Hills, MI.
ASTM. (2014). “Standard specification for deformed and plain low-alloy steel bars for concrete reinforcement.” ASTM A706, West Conshohoken, PA.
Brown, M. D. (2005). “Design for shear in reinforced concrete using strut-and-tie and sectional models.” Ph.D. dissertation, Dept. of Civil, Architectural, and Environmental Engineering, Univ. of Texas at Austin, Austin, TX.
Cao, S. Y., Chen, J. F., Teng, J. G., Hao, Z., and Chen, J. (2005). “Debonding in RC beams shear strengthened with complete FRP wraps.” J. Compos. Constr., 417–428.
Chaallal, O., Nollet, M.-J., and Perraton, D. (1998). “Shear strengthening of RC beams by externally bonded side CFRP strips.” J. Compos. Constr., 111–113.
El-Maaddawy, T., and El-Ariss, B. (2012). “Behavior of concrete beams with short shear span and web opening strengthened in shear with CFRP composites.” J. Compos. Constr., 47–59.
Kim, C. (2014). “Performance of concrete panels strengthened using carbon fiber reinforced polymers (CFRP).” Ph.D. dissertation, Dept. of Civil, Architectural, and Environmental Engineering, Univ. of Texas at Austin, Austin, TX.
Kim, I., Jirsa, J., and Bayrak, O. (2007). “Use of CFRP to strengthen poorly detailed reinforced concrete beams under dynamic loading.” Proc., 8th Int. Symp. on Fiber Reinforces Polymer Reinforcement for Concrete Structures, Univ. of Patras, Patras, Greece.
Kim, Y., et al. (2012). “Shear strengthening of reinforced and prestressed concrete beams using carbon fiber reinforced polymer (CFRP) sheets and anchors.”, Center for Transportation Research, Univ. of Texas at Austin, Austin, TX, 226–229.
Kim, Y., Quinn, K., Ghannoum, W., and Jirsa, J. (2014). “Strengthening of reinforced concrete T-beams using anchored CFRP materials.” ACI Struct. J., 111(5), 1027–1036.
Koutas, L., and Triantafillou, T. C. (2013). “Use of anchors in shear strengthening of reinforced concrete T-beams with FRP.” J. Compos. Constr., 101–107.
Sokoli, D., Shekarchi, W., Buenrostro, E., and Ghannoum, W. (2014). “Advancing behavioral understanding and damage evaluation of concrete members using high-resolution digital image correlation data.” Earthquakes Struct., 7(5), 609–626.
Sun, S., Jirsa, J., and Ghannoum, W. (2016). “Behavior of anchored carbon fiber-reinforced polymer strips used for strengthening concrete structures.” ACI Mater. J., 113(2), 163–172.
Zhang, Z., and Hsu, C. T. T. (2005). “Shear strengthening of reinforced concrete beams using carbon-fiber-reinforced polymer laminates.” J. Compos. Constr., 158–169.
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Published In
Journal of Composites for Construction
Volume 21 • Issue 3 • June 2017
Copyright
©2016 American Society of Civil Engineers.
History
Received: Mar 28, 2016
Accepted: Aug 11, 2016
Published online: Oct 5, 2016
Discussion open until: Mar 5, 2017
Published in print: Jun 1, 2017
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