Shear Strengthening of T Cross Section Reinforced Concrete Beams by Near-Surface Mounted Technique
Publication: Journal of Composites for Construction
Volume 12, Issue 3
Abstract
With the purpose of evaluating the influence of both the percentage and inclination of the carbon fiber-reinforced polymer (CFRP) laminates on the effectiveness of the near-surface mounted technique for the shear strengthening of reinforced concrete T beams, an experimental program was carried out, using three percentages of laminates and, for each one, three inclinations: 90, 60, and . The CFRP-strengthened beams had a steel stirrup reinforcement ratio of 0.1%. The highest CFRP percentage was designed to provide a maximum load similar to the one of a reference beam reinforced with equal to 0.24%. Although these beams have had a similar maximum load, the beams with CFRP presented higher stiffness. Laminates at was the most effective shear strengthening configuration, having provided a maximum increase in the load capacity of 33%. The contribution of the CFRP strengthening systems was limited by the concrete tensile strength. Below certain spacing between laminates, a group effect occurs due to the interference between consecutive concrete failure surfaces, leading to the detachment of “two lateral walls” from the underlying beam core.
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Acknowledgments
The writers of the present work wish to acknowledge the support provided by the “Empreiteiros Casais”, S&P, degussa Portugal, and Secil (Unibetão, Braga). The study reported in this paper forms a part of the research program “CUTINSHEAR—performance assessment of an innovative structural FRP strengthening technique using an integrated system based on optical fiber sensors” supported by FCT, Grant No. UNSPECIFIEDPOCTI/ECM/59033/2004.
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Information & Authors
Information
Published In
Journal of Composites for Construction
Volume 12 • Issue 3 • June 2008
Pages: 300 - 311
Copyright
© 2008 ASCE.
History
Received: Oct 24, 2006
Accepted: Aug 13, 2007
Published online: Jun 1, 2008
Published in print: Jun 2008
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