Abstract
This paper presents the results of an investigation of reinforced concrete (RC) T-beams retrofitted in shear with near-surface mounted (NSM) fiber-reinforced polymer (FRP) rods. Six full-scale 4,520-mm-long RC T-beams were tested to study the effects of important parameters such as the presence of NSM FRP rods, the presence of steel stirrups, and the steel stirrup ratio. This paper provides an insightful and comprehensive description of the behavior of strengthened T-beams under increasing load, from the formation of the first crack to ultimate failure. The results of this study and those gathered in the presented database show that existing steel stirrups and strengthening NSM FRP did not diminish each other’s effect when failure modes unrelated to shear resistance of RC beams were prevented. The experimental results of this study and those in the database were used to verify a newly proposed model to predict the shear contribution of NSM FRP rods and laminates in RC beams strengthened in shear. The proposed model showed an improved accuracy compared with the existing models in the literature.
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Acknowledgments
The authors acknowledge the support provided by Mitacs and Sika Canada Inc. through a Mitacs postdoctoral fellowship to Dr. Mofidi, by the Natural Sciences and Engineering Research Council of Canada through a Discovery grant to Prof. Chaallal, and by the University of California, Davis for partial financial support of the research. The authors thank Mr. Philippe Guevremont and Mr. Bob Barham at Sika Canada Inc. for their contributions to this research. The efficient collaboration of John Lescelleur (senior technician) at ÉTS, in conducting the tests, is acknowledged.
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Information & Authors
Information
Published In
Journal of Composites for Construction
Volume 20 • Issue 2 • April 2016
Copyright
© 2015 American Society of Civil Engineers.
History
Received: Nov 14, 2014
Accepted: Jul 2, 2015
Published online: Sep 3, 2015
Discussion open until: Feb 3, 2016
Published in print: Apr 1, 2016
ASCE Technical Topics:
- Beams
- Composite beams
- Composite materials
- Concrete
- Concrete beams
- Construction engineering
- Construction methods
- Engineering materials (by type)
- Fiber reinforced composites
- Fiber reinforced concrete
- Fiber reinforced polymer
- Fluid mechanics
- Hydrologic engineering
- Materials engineering
- Polymer
- Rehabilitation
- Reinforced concrete
- Shear resistance
- Structural engineering
- Structural members
- Structural systems
- Synthetic materials
- Viscosity
- Water and water resources
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