Experimental Investigation of Reinforced Concrete T-Beams Strengthened in Shear with Externally Bonded CFRP Sheets
Publication: Journal of Composites for Construction
Volume 21, Issue 2
Abstract
An experimental investigation was undertaken into the effectiveness of unanchored and anchored externally bonded (EB) U-wrapped carbon fiber–reinforced polymer (CFRP) shear strengthening for reinforced concrete T-beams at a range of realistic sizes. The T-beam sizes, geometry, and reinforcement were chosen to reflect existing slab-on-beam structures with low levels of transverse steel shear reinforcement. Geometrically similar reinforced concrete T-beams were tested across three sizes ranging from 360 to 720 mm in depth and with different amounts of EB CFRP shear reinforcement. The beams were subjected to three-point bending with a span-to-depth ratio of 3.5. All the beams failed in diagonal shear. The experimental results indicate significant variability in the capacity of unstrengthened control beams, and a number of these control beams showed greater shear capacity than their EB CFRP-strengthened counterparts. Greater thicknesses of CFRP reinforcement did not lead to increased shear capacity compared with less thicknesses of unanchored or anchored EB CFRP, but anchored EB CFRP did lead to moderate increases in shear capacity compared with both control and unanchored EB CFRP-strengthened beams.
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Acknowledgments
The authors gratefully acknowledge the help of the laboratory staff of University of Bath and University of Cambridge. The authors would also like to acknowledge the financial support of the U.K. Engineering and Physical Sciences Research Council (under grants EPSRC EP/I018921/1 and EP/I018972/1); the University of Bath and University of Cambridge; and the project partners and sponsors—Parsons Brinckerhoff, Tony Gee and Partners LLP, Arup, Highways England, Concrete Repairs Ltd., LG Mouchel and Partners, the Concrete Society, Fyfe Europe S.A., Fibrwrap UK, Hughes Brothers, and Ebor Concrete Ltd. Additional data related to this publication are available at the institutional data repositories of the University of Cambridge (https://doi.org/10.17863/CAM.297) and the University of Bath (https://doi.org/10.15125/BATH-00210).
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Information & Authors
Information
Published In
Journal of Composites for Construction
Volume 21 • Issue 2 • April 2017
Copyright
©2016 American Society of Civil Engineers.
History
Received: Apr 13, 2016
Accepted: Jun 21, 2016
Published online: Aug 12, 2016
Discussion open until: Jan 12, 2017
Published in print: Apr 1, 2017
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