Design Proposal to Avoid Peeling Failure in FRP-Strengthened Reinforced Concrete Beams
Publication: Journal of Composites for Construction
Volume 13, Issue 5
Abstract
According to the available experimental work, the most common failure in existing structures strengthened by plate bonding is the laminate peeling off. In the last few years, an important effort in the development of mathematical models to avoid premature peeling failures has been made. However, a suitable and reliable design method to predict debonding due to the shear flow between crack discontinuities or at the laminate end is still not available. This paper describes a new design procedure for structures strengthened by plate bonding to avoid peeling failure at any location. After calculating the laminate area required for flexural strengthening, a two-step procedure to prevent peeling failure is proposed. The first step, to avoid peeling failure along the span, is based on a shear-bending interaction diagram associated with the theoretical maximum transferred force between laminate and support along the crack spacing before laminate debonding. This interaction diagram can be obtained through the application of nonlinear fracture mechanics. The second step consists of checking for peeling failure at the laminate end. The bonded length between the laminate end and the nearest crack should be enough to transfer the laminate tensile force acting on this crack. The proposed method has been verified with available experimental results assembled in a database. A good agreement between the experimental and predicted failure load has been obtained. Finally, an application example is presented to show the applicability of the method.
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References
Ali, M., Oelhers, D. J., and Bradford, M. A. (2001). “Shear peeling of steel plates bonded to tension faces of RC beams.” J. Struct. Eng., 127(12), 1453–1459.
American Concrete Institute (ACI). (2002). “Guide for the design and construction of externally bonded FRP systems for strengthening concrete structures.” ACI 440, Detroit.
Brosens, K. (2001). “Anchorage of externally bonded steel plates and CFRP laminates for the strengthening of concrete elements.” Ph.D. thesis, Katholieke Universiteit Leuven, Belgium.
Brosens, K., and Van Gemert, D. (1998). “Plate end shear design for external CFRP laminates.” Proc., FRAMCOS-3, Aedificatio Publishers, Freiburg, 1793–1804.
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.
Collins, M. P. (2001). “Evaluation of shear design procedures for concrete structures.” Rep. Prepared for the CSA Technical Committee on Reinforced Concrete Design, Canada.
Colotti, V., and Spadea, G. (2001). “Shear strength of RC beams strengthened with bonded steel or FRP plates.” J. Struct. Eng., 127(4), 367–373.
European Committee for Standardization. (1992). “Design of concrete structures. Part 1–1: General rules and rules for building.” Eurocode 2.
fib bulletin 14. (2001). “Externally bonded FRP reinforcement for RC structures.” Technical Rep. Prepared for Task Group 9.3 FRP Reinforcement for Concrete Structures FIB International Federation for Structural Concrete, Laussane, Switzerland.
Lu, X. Z., Teng, J. G., Ye, L. P., and Jiang, J. J. (2007). “Intermediate crack debonding in FRP-strengthened RC beams: FE analysis and strength model.” J. Compos. Constr., 11(2), 161–174.
Neubauer, U. (2000). “Verbundtragverhalten geklebter Lamellen aus Kohlenstoffaser-Verbundwerkstoff zur Verstärkung von Betonbauteilen.” Ph.D. thesis, TU Braunschweig, Germany.
Niedermeier, R. (2000). “Envelope line of tensile forces while using externally bonded reinforcement.” Ph.D. thesis, TU Münich, Munchen.
Oller, E. (2005). “Peeling failure in beams strengthened by plate bonding. A design proposal.” Ph.D. thesis, Technical University of Catalonia, Spain.
Oller, E., Cobo, D., and Marí, A. R. (2009). “Interface behavior in FRP-strengthened beams subjected to transverse loads: Maximum transferred force.” J. Compos. Constr., 13(1) 35–44.
Raoof, M., and Zhang, S. (1997). “An insight into the structural behaviour of reinforced concrete beams with externally bonded plates.” Proc. Inst. Civ. Eng. Struct. Build., 122, 477–492.
Said, H., and Wu, Z. (2008). “Evaluating and proposing models of predicting IC debonding failure.” J. Compos. Constr., 12(3), 284–299.
Täljsten, B. (1994). “Plate bonding. strengthening of existing concrete structures with epoxy bonded plates of steel or fibre reinforced plastics.” Ph.D. thesis, Lule University of Technology, Sweden.
Teng, J. G., Smith, S. T., Yao, J., and Chen, J. F. (2003). “Intermediate crack-induced debonding in RC beams and slabs.” Constr. Build. Mater., 17(6–7), 447–462.
Vasseur, L., Matthys, S., and Taerwe, L., and (2008). “Bond behaviour of externally bonded FRP to concrete in the case of 3-point bending tests.” Proc., Challenges of Civil Construction, T. Marques et al., eds., FEUP, Porto, Portugal, 164–165.
Wu, Z. and Niu, H. D. (2000). “Study on debonding failure load of RC beams strengthened with FRP sheets.” J. Struct. Eng., 46(A), 1431–1441 (in Japanese).
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© 2009 ASCE.
History
Received: Jul 4, 2008
Accepted: Mar 11, 2009
Published online: Mar 23, 2009
Published in print: Oct 2009
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