Fundamental Mechanics Governing FRP-Retrofitted RC Beams with Anchored and Prestressed FRP Plates
Publication: Journal of Composites for Construction
Volume 20, Issue 6
Abstract
It is often found that a major limitation to retrofitting RC beams by adhesive bonding fiber-reinforced polymer (FRP) plates is premature debonding, which restricts the FRP strains to well below that at fracture. Tests have shown that the FRP peak strains can be increased by anchoring the plate ends of adhesively bonded plates and also by prestressing the anchored plates before adhesive bonding, both of which make the system much more efficient. In this paper, a mechanics-based numerical approach is developed that quantifies the stiffness, strength, and ductility of FRP retrofitted RC beams, in which the FRP plates are anchored, prestressed, and adhesively bonded. The approach can cope with any degree of anchorage and prestress and whether adhesively bonded or not. The approach is generic as it can be applied to any type of RC beam, anchor, and FRP plate and any distribution of load. Furthermore, it allows for discrete flexural cracks and for the formation of softening hinges should these occur. Worked examples are given as a possible design approach. This paper provides a design tool for engineers to develop and quantify their own FRP retrofitting systems for beams with anchored plates.
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Published In
Journal of Composites for Construction
Volume 20 • Issue 6 • December 2016
Copyright
© 2016 American Society of Civil Engineers.
History
Received: Nov 23, 2015
Accepted: Mar 3, 2016
Published online: Apr 29, 2016
Discussion open until: Sep 29, 2016
Published in print: Dec 1, 2016
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