Size Effect in RC T-Beams Strengthened in Shear with Externally Bonded CFRP Sheets: Experimental Study
Publication: Journal of Composites for Construction
Volume 23, Issue 6
Abstract
Numerous investigations have addressed the size effect on the shear behavior of conventional reinforced concrete (RC) beams. In contrast, very few studies have been dedicated to the size effect of RC beams strengthened in shear with externally bonded (EB) fiber-reinforced polymer (FRP) sheets. This paper presents the results of an experimental investigation conducted on 18 RC T-beam specimens of three different sizes to study the size effect on concrete shear strength at failure of RC beams strengthened in shear with EB carbon FRP (CFRP) sheets. The specimens were divided into two groups, with and without internal transverse steel, and six series, each consisting of small, medium, and large beams as follows: two series of control (unstrengthened) specimens, two series of specimens strengthened in shear with one-ply EB-CFRP sheets in a U-wrap configuration, and two series of specimens strengthened in shear with two plies of EB-CFRP sheets in a U-wrap configuration. The results clearly revealed the presence of a size effect on both the concrete and CFRP sheet contribution to shear resistance. For strengthened specimens without internal transverse steel, the size effect was found to be magnified as the CFRP sheet stiffness increased. This was not the case for beams strengthened with transverse steel, where the size effect behavior reduced considerably due to the interaction between internal transverse steel and EB-CFRP sheets.
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Acknowledgments
The financial support of the Natural Sciences and Engineering Research Council of Canada (NSERC) and the Fonds de recherche du Québec–Nature et technologie (FRQNT) through operating grants is gratefully acknowledged. The authors thank Sika-Canada, Inc. (Pointe Claire, Quebec) for contributing to the cost of the materials. The efficient collaboration of John Lescelleur (senior technician) and Andrés Barco (technician) at École de technologie supérieure (ÉTS) in conducting the tests is acknowledged.
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Published In
Journal of Composites for Construction
Volume 23 • Issue 6 • December 2019
Copyright
©2019 American Society of Civil Engineers.
History
Received: Aug 29, 2018
Accepted: Apr 4, 2019
Published online: Sep 19, 2019
Published in print: Dec 1, 2019
Discussion open until: Feb 19, 2020
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