Strength Reduction Factor for Flexural RC Members Strengthened with Near-Surface-Mounted Bars
Publication: Journal of Composites for Construction
Volume 17, Issue 5
Abstract
Current American Concrete Institute (ACI) guidelines for the design of flexural RC members strengthened with externally bonded fiber-reinforced polymer (FRP) systems assign an additional partial strength reduction factor to the contribution of FRP, marking a deviation from ACI’s approach in building codes. This conservative method finds its rationale in the novelty and the higher variability of FRP, because of its nature as a material (compared to steel) and the conditions of its installation (externally bonded). Using the case of near-surface-mounted (NSM) FRP bars, this paper demonstrates that a single strength reduction factor can be formulated, while maintaining the same reliability and safety required in conventional RC members. Using a comprehensive test matrix of flexural members processed with a computerized Monte Carlo simulation technique, the probabilistic implications of strengthening RC beams and slabs with NSM FRP bars are investigated. The generated statistical data are employed to recommend revised strength reduction factors for flexural RC members strengthened with NSM FRP bars that eliminate the partial factor, and yet, provide a safety level equal to ordinary steel RC members.
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Acknowledgments
The authors gratefully acknowledge the financial support for this research provided by the NSF under grant IIP-0933537 as well as the contribution of the industry members to the NSF Industry/University Cooperative Research Center based at the University of Miami.
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Information & Authors
Information
Published In
Journal of Composites for Construction
Volume 17 • Issue 5 • October 2013
Pages: 614 - 625
Copyright
© 2013 American Society of Civil Engineers.
History
Received: Aug 27, 2012
Accepted: Jan 22, 2013
Published online: Jan 24, 2013
Discussion open until: Jun 24, 2013
Published in print: Oct 1, 2013
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