Assessing the Strengthening Effect of Various Near-Surface-Mounted FRP Reinforcements on Concrete Bridge Slab Overhangs
Publication: Journal of Composites for Construction
Volume 15, Issue 4
Abstract
The near-surface-mounted (NSM) method has proved to be a reliable alternative to the existing externally bonded (EB) method for the repair and strengthening of concrete structures using fiber-reinforced polymer (FRP) composites. This technique is especially advantageous in bridge deck upgrades for larger barriers and slab overhang strengthening. This paper presents the results of a comparison of the flexural behavior of bridge slab overhangs strengthened in negative bending moment regions with various types of NSM reinforcement that differ in surface condition (e.g., textured and sand coated), cross-sectional shape (e.g., round and square), material type (carbon and glass), and prestressing effect. Eleven full-scale overhang specimens (1.524 m long in overhang and 0.914 m wide) were tested under a cantilever condition. Test results showed that the FRP NSM reinforcements were effective in increasing both yield and ultimate strength of predamaged slab overhangs. All surface treatments were more beneficial than the smooth condition, and the square-shaped reinforcement displayed better performance than the round shape. The prestressing unit developed in this study is simple to apply and could be further explored for field applications.
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Acknowledgments
The research was conducted with the partial financial support of the California Department of Transportation (Caltrans). Laboratory assistance on the test from the laboratory technicians and undergraduate research assistants in the group is greatly appreciated. The authors would also like to thank, in no particular order, Sireg, Sika, Sto, Hughes Brothers, and Dongwon Construction for their kind donation of some of the FRP products studied here. Any opinions expressed in this paper are those of the authors and do not necessarily reflect the views of either Caltrans or industrial sponsors.
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Information
Published In
Journal of Composites for Construction
Volume 15 • Issue 4 • August 2011
Pages: 615 - 624
Copyright
© 2011 American Society of Civil Engineers.
History
Received: May 1, 2010
Accepted: Oct 18, 2010
Published online: Oct 20, 2010
Published in print: Aug 1, 2011
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