Interfacial Stresses in RC Beams Strengthened by Externally Bonded FRP/Steel Plates with Effects of Shear Deformations
Publication: Journal of Composites for Construction
Volume 16, Issue 1
Abstract
This paper introduces an analytical method to calculate the interfacial shear and normal stresses in reinforced concrete (RC) beams strengthened by a fiber reinforced polymer (FRP) sheet or a steel plate (i.e., a soffit plate). The maximum interfacial shear and normal stresses are localized at the end of the soffit plate, and as a result, a debonding phenomenon develops at this position and may produce a sudden failure of the structure. The effects of the shear deformations are calculated in an RC beam, an adhesive layer, and a soffit plate. Thus, the composite RC beam is assumed to be a Timoshenko beam. Application of shear deformations to a Timoshenko beam results in a pair of simultaneous second-order and fourth-order ordinary differential equations. In the engineering literature, these equations are called coupled differential equations. These coupled equations are solved analytically considering all terms. The present paper illustrates the effects of interfacial stresses on the behavior of RC structures strengthened by FRP sheets or steel plates. Finally, the agreement of the results obtained from the analytical solution and the results available in the literature confirms the accuracy of the proposed approach in predicting both interfacial shear and normal stresses.
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Acknowledgments
The work described in this paper was fully supported by a research grant via Ferdowsi University of Mashhad (FUM). The authors are grateful for the financial support. Also the first author is thankful to Ilam University for his study assignment.
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Published In
Journal of Composites for Construction
Volume 16 • Issue 1 • February 2012
Pages: 60 - 73
Copyright
© 2012. American Society of Civil Engineers.
History
Received: Jan 24, 2011
Accepted: Jun 14, 2011
Published in print: Feb 1, 2012
Published online: Apr 27, 2012
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