Normalized Test for Prediction of Debonding Failure in Concrete Elements Strengthened with CFRP
Publication: Journal of Composites for Construction
Volume 10, Issue 6
Abstract
This work presents the results of an experimental research program, carried out at the Technical University of Catalonia, to study the debonding behavior of carbon fiber-reinforced polymers (CFRPs) used to strengthen beams in bending. The research is a part of a program that aims to study the strengthening of concrete bridges (both monolithic and segmental) using CFRPs. The overall objective of this paper is to present the results obtained from bond tests performed on material-scale specimens and full-scale tests performed on monolithic and segmental beams. A normalized test is proposed to obtain a more reliable estimate of the debonding strain of CFRPs, which may govern the design of CFRP-strengthened concrete structures. The test is proposed to supplement available design models, as the formula of included in ACI 440.2R-02 by ACI Committee 440. The results from the tests are checked with the data obtained in large-scale tests, representative of actual bridges. The reported values are significantly lower than those reported in other tests with specimens of a lower size. An explanation is that a size effect can exist, which affects the debonding failure mechanisms. Extrapolation of results—from models calibrated with specimens of reduced dimensions to real structures—may lead to unsafe predictions of the debonding strain. In conclusion, the proposed simplified bond test more accurately estimates the load bearing capacity, which in practical cases is not perfectly well covered by the existing models; for instance when discontinuities (cracks or joints) are present in the concrete where the CFRP is bonded.
Get full access to this article
View all available purchase options and get full access to this article.
Acknowledgments
The writers especially thank the Spanish Ministry of Public Works and the Spanish Ministry of Education and Science for the financial support received through the Research Project MAT 2002-00849 to carry out the different tests performed in this study. Likewise, they thank Freyssinet, Bettor, and Fosroc, who kindly provided the repairing materials used in the experimental campaign.
References
Alarcón, A. (2003). “Theoretical and experimental study on the repair and strengthening of segmental bridges with carbon fibers.” Ph.D. thesis, Univ. Politécnica de Catalunya, Barcelona, Spain (in Spanish).
Alarcón, A., Ramos, G., and Casas, J. R. (2001). “The segmental effect on shear and flexural strengthening using CFRPs.” Proc., 3rd Int. Conf. on Concrete under Severe Conditions, Vancouver, Canada, 234–241.
American Concrete Institute (ACI). (2002). “Guide for the design and construction of externally bonded FRP systems for strengthening concrete structures.” ACI 440.2R-02, ACI Committee 440, Farmington Hills, Mich.
Anllo, M. (1996). “Experimental analysis up to failure of externally prestressed concrete beams.” MS thesis, Univ. Politècnica de Catalunya, Barcelona, Spain (in Spanish).
Arduini, M., Nanni, A. and Romagnolo, M. (2002). “Performance of decommissioned reinforced concrete girders strengthened with fiber-reinforced polymer laminates.” ACI Struct. J., 99(5), 652–659.
ASTM. (1989). “Standard test method for tensile properties of fiber-resin composites.” ASTM D 3039-76, West Conshohocken, Pa.
Brosens, K., and Van Gemert, D. (1997). “Anchoring stresses between concrete and carbon fiber reinforced laminates. Nonmetallic (FRP) reinforcement for concrete structures.” Proc., 3rd Int. Symp., Japan Concrete Institute, Sapporo, 1, 271–278.
Buyukozturk, O., and Hearing, B. (1998). “Failure behavior of precracked concrete beams retrofitted with FRP.” J. Compos. Constr., 2(3), 138–144.
Camata, G., Spacone, E., Al-Mahaidi, R., and Saouma, V. (2004). “Analysis of test specimens for cohesive near-bond failure of fiber-reinforced polymer-plated concrete.” J. Compos. Constr., 8(6), 528–538.
Chajes, M. J., Finch, W. W., Jr., Januzska, T. F., and Thomson, T. A., Jr. (1996). “Bond and force transfer of composite material plates bonded to concrete.” ACI Struct. J., 93(2), 295–303.
Chen, J. F., and Teng, J. G. (2001). “Anchorage strength models for FRP and steel plates bonded to concrete.” J. Struct. Eng., 127(7), 784–791.
Chen, J. F., Yang, Z. J., and Holt, G. D. (2001). “FRP or steel plate-to-concrete bonded joints: Effect of test methods on experimental bond strength.” Steel Compos. Struct., 1(2), 231–244.
De Lorenzis, L., Miller, B., and Nanni, A. (2001). “Bond of fiber-reinforced polymer laminates to concrete.” ACI Mater. J., 98(3), 256–264.
Di Ludovico, M., Nanni, A., Prota, A., and Cosenza, E. (2005). “Repair of bridge girders with composites: Experimental and analytical validation.” ACI Struct. J., 102(5), 639–648.
Federation Internationalle du Béton (FIB). (2001). “Externally bonded FRP reinforcement for RC structures.” Bull. No. 14. Laussane, Switzerland.
Freyssinet. (1998). Strengthening by gluing carbon fiber mesh, TFC procedure, Technical specifications, Freyssinet, France.
Gómez, D. (1995). “Failure tests of externally prestressed concrete beams.” MS thesis, Univ. Politècnica de Catalunya, Barcelona, Spain.
Harmon, T. G., Kim, Y. J., Kardos, J., Johnson, T., and Stark, A. (2003). “Bond of surface-mounted fiber-reinforced polymer reinforcement for concrete structures.” ACI Struct. J., 100(5), 557–564.
Kobatake, Y., Kimura, K., and Ktsumata, H. (1993). “A retrofitting method for reinforced concrete structures using carbon fibers.” Fibre-reinforced-plastic (FRP) reinforcement for concrete structures: Properties and applications, A. Nanni, ed., Elsevier Science, Amsterdam, The Netherlands, 435–450.
Landa, G. (2001). “Behavior of FRPs on shear strengthening of reinforced concrete beams.” Ph.D. thesis, Univ. Politècnica de Catalunya, Barcelona, Spain (in Spanish).
Lee, K. (2003). “Shear strength of reinforced concrete T-beams strengthened using CFRP laminates.” Ph.D. thesis, Dept. of Civil Engineering, Monash Univ., Melbourne, Australia.
Maeda, T., Asano, Y., Sato, Y., Ueda, T., and Kakuta, Y. (1997). “A study on bond mechanism of carbon fiber sheet: Non-metallic (FRP) reinforcement for concrete structures.” Proc., 3rd Int. Symp., Japan Concrete Institute, Sapporo, 1, 279–285.
Miller, B., and Nanni, A. (1999). “Bond between carbon fiber reinforced polymer sheets and concrete.” Proc., ASCE 5th Materials Congress, L. C. Bank, ed., New York, 240–247.
Neubauer, U., and Rostásy, F. S. (1997). “Design aspects of concrete structures strengthened with externally bonded CFRP plates.” Proc., 7th Int. Conf. on Structural Faults and Repair, ECS Publications, Edinburgh, Scotland, 2, 109–118.
Salaverría, J. (2003). “Utilization of new materials for the repair and strengthening of bridges.” Ph.D. thesis, Univ. Politècnica de Catalunya, Barcelona, Spain (in Spanish).
Salaverría, J., and Casas, J. R. (1998). “Aramid fibers used for bridge repair and strengthening.” IABSE Symp. Long-Span and High-Rise Structures.
Salaverría, J., Casas, J. R., and Aparicio, A. C. (1997). “Experimental study on the use of aramid composites for repair and strengthening of existing bridges.” Structural faults and repair 97, Edinburgh, U.K.
Shahrooz, B., Boy, S., and Baseheart, M. (2002). “Flexural strengthening of four 76-year-old T-beams with various fiber-reinforced polymer systems: Testing and analysis.” ACI Struct. J., 99(5), 681–691.
Scherer, J. (1998). “S&P structural reinforcing system with carbon fiber sheets.” Technical specifications, S&P Cleaver Reinforcement Company, Brunnen, Switzerland.
Swamy, R. N., Jones, R., and Charif, A. (1986). “Shear adhesion properties of epoxy resin adhesives.” Proc., Int. Symp. on Adhesion Between Polymers and Concrete, Chapman and Hall, London, 741–755.
Täljsten, B. (1997). “Defining anchor lengths of steel and CFRP plates bonded to concrete.” Int. J. Adhes. Adhes., 17(4), 319–327.
Teng, J. G., Chen, J. F., Smith, S. T., and Lam, L. (2002). “FRP strengthened RC structures.” Wiley, Chichester, England.
Teng, J. G., Chen, J. F., Smith, S. T., and Lam, L. (2003). “Behaviour and strength of FRP-strengthened RC structures: A state-of-the-art review.” Proc. Inst. Civ. Eng., Struct. Build., 156(1), 51–62.
The Concrete Society. (2000). “Design guidance for strengthening concrete structures using fibre composite materials.” Tech. Rep. No. 55, Crowthorne, U.K.
Triantafillou, T., and Deskovic, N. (1991). “Innovative prestressing with FRP sheets: Mechanics of short-term behavior.” J. Eng. Mech., 117(7), 1652–1672.
Volnyy, V. A., and Pantelides, C. P. (1999). “Bond length of CFRP composites attached to precast concrete walls.” J. Compos. Constr., 3(4), 168–176.
Yoshizawa, H., Myojo, T., Okoshi, M., Mizukoshi, M., and Kliger, H. S. (1996). “Effect of sheet bonding condition on concrete members having externally bonded carbon fiber sheet.” Proc., 4th Materials Engineering Conf., ASCE Annual Convention, New York, 1608–1616.
Information & Authors
Information
Published In
Journal of Composites for Construction
Volume 10 • Issue 6 • December 2006
Pages: 509 - 519
Copyright
© 2006 ASCE.
History
Received: Aug 2, 2005
Accepted: Feb 14, 2006
Published online: Dec 1, 2006
Published in print: Dec 2006
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.