Behavior of Prestressed Hollow-Core Slabs Strengthened in Flexure with Near-Surface Mounted Carbon Fiber-Reinforced Polymer Reinforcement
Publication: Journal of Composites for Construction
Volume 20, Issue 6
Abstract
Flexural strengthening of reinforced concrete using near-surface mounted (NSM) fiber-reinforced polymer (FRP) composites is a widely studied topic, and a promising technology. However, overlooked applications such as prestressed concrete and one-way slabs require further experimental investigation and theoretical refinement in order to develop comprehensive design guidelines. This paper investigates the behavior of prestressed hollow-core slabs strengthened in flexure with NSM carbon FRP strip reinforcement. Seven full-scale simply supported slab specimens were tested to failure under two-point monotonic load configuration. Experimental variables included two different internal prestressing reinforcement ratios, and three different NSM strengthening reinforcement ratios. This paper examines cracking behavior and modes of failure, load-strain relationships, deflections, and strengthened capacities. Also, a comparison between experimental results and theoretical predictions by relevant Canadian and American standards or guidelines is presented.
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Acknowledgments
The authors wish to express their gratitude and sincere appreciation for the financial support received from the Natural Science and Engineering Research Centre (NSERC) through the Canada Research Chair Program (CRC). In addition, a sincere thank-you goes to the technical staff at the University of Manitoba’s W.R. McQuade Structures Laboratory, Tetra Tech Inc., Lafarge Canada Inc., and Vector Construction Ltd. for their continued support and in-kind contributions.
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© 2016 American Society of Civil Engineers.
History
Received: Oct 18, 2015
Accepted: Jan 22, 2016
Published online: Apr 1, 2016
Discussion open until: Sep 1, 2016
Published in print: Dec 1, 2016
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