Tests on RC Beams Strengthened at the Span with Externally Bonded Polymers Reinforced with Carbon or Steel Fibers
Publication: Journal of Composites for Construction
Volume 16, Issue 5
Abstract
The main objective of the experimental work reported herein is the comparative evaluation of steel-reinforced polymers (SRPs) and carbon-reinforced polymers (CFRPs) used as externally-bonded reinforcement in strengthening of reinforced-concrete (RC) members. Tensile stress strain as well as bond constitutive laws for these materials were first derived from 16 tests and are summarized here. Results are then reported from four-point bending tests of five full-scale RC beams strengthened at their span using SRP and CFRP strips. The bond tests have shown that by providing a bond length greater than the effective one, neither the bond strength nor the deformation capacity are increased, whereas by increasing the width of the strip the bond strength is increased. From the bending tests of beams it was found that the use of both SRP and CFRP strips resulted in a significant increase in strength (up to 92%) with respect to the strength of the initial specimen. The experimentally measured strengths were estimated analytically using both the experimental measurements of the specimen deformations and the pertinent provisions of standards from the American Concrete Institute and the European Committee for Standardization.
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Acknowledgments
The research project, results of which are present in this paper, was jointly funded by EU-European Social Fund, the Greek Ministry of Development-GSRT, and Sika-Hellas.
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Information & Authors
Information
Published In
Journal of Composites for Construction
Volume 16 • Issue 5 • October 2012
Pages: 551 - 562
Copyright
© 2012 American Society of Civil Engineers.
History
Received: Jun 21, 2011
Accepted: Jan 31, 2012
Published online: Sep 14, 2012
Published in print: Oct 1, 2012
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