CFRP Shear Strengthening of Reinforced-Concrete T-Beams with Corroded Shear Links
Publication: Journal of Composites for Construction
Volume 19, Issue 5
Abstract
This paper investigates the structural behavior of uncorroded as well as corroded RC T-beams strengthened in shear with either externally bonded (EB) carbon fiber–reinforced polymer (CFRP) sheets or embedded CFRP rods. Nine tests were carried out on RC T-beams having an effective depth of 295 mm and a shear span to effective depth ratio of 3.05. The investigated parameters are the shear link corrosion level (uncorroded, 7% corroded, or 12% corroded) and type of CFRP strengthening system (EB CFRP sheets or embedded CFRP rods). The unstrengthened beams with shear link corrosion levels of 7 and 12% had shear strengths that were 11 and 14%, respectively, less than the shear strength of the uncorroded unstrengthened beam. Both the embedded CFRP rods and EB CFRP sheets were effective in enhancing the shear strength of tested beams but the effectiveness of both strengthening systems decreased with increasing shear link corrosion level. The shear strength enhancement provided by the embedded CFRP rods and EB CFRP sheets decreased from 19 and 15%, respectively, to 12 and 11%, respectively, with an increase in shear link corrosion level from 7 to 12%. Corrosion of the shear links did not have a significant effect on the beam stiffness. Premature debonding limited the effectiveness of the EB CFRP sheets whereas the embedded CFRP rods did not exhibit signs of debonding and therefore showed higher effectiveness.
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Acknowledgments
The writers would like to thank Fyfe Europe for supplying the CFRP sheets and epoxy laminating resin used in the research reported in this paper. The first writer acknowledges the financial support of the U.K. Engineering and Physical Sciences Research Council.
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Published In
Journal of Composites for Construction
Volume 19 • Issue 5 • October 2015
Copyright
© 2014 American Society of Civil Engineers.
History
Received: Jun 24, 2014
Accepted: Nov 17, 2014
Published online: Dec 17, 2014
Discussion open until: May 17, 2015
Published in print: Oct 1, 2015
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