Experimental Study of Interfacial Shear Stresses in FRP-Strengthened RC Beams
Publication: Journal of Composites for Construction
Volume 12, Issue 3
Abstract
This paper presents the results of an experimental study on the distribution of shear stresses along the interface between concrete and the carbon fiber-reinforced polymer (FRP) in 29 plate-strengthened beams, where the primary test variables are: Clear cover, plate length, plate thickness (area), and compressive strength of concrete. FRP strain measurement was accomplished using either the photographic technique of digital image correlation or a series of electrical-resistance strain gages, both providing similar results. The distribution of shear stresses is found to be smoother than predicted by several analytical expressions available in the literature. Another substantial observation is the existence of a second region of peak stress, occurring near the center of the shear span in all of the beams with longer plate lengths, which the authors believe is associated with the singular application of shear corresponding to the point load, as well as the transition from elastic to plastic behavior occurring in the rebar. Because the overall nature of the stress distribution is sufficiently smooth, it is very reasonable to approximate it as a constant stress.
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Information
Published In
Journal of Composites for Construction
Volume 12 • Issue 3 • June 2008
Pages: 312 - 322
Copyright
© 2008 ASCE.
History
Received: Jun 22, 2006
Accepted: Aug 24, 2006
Published online: Jun 1, 2008
Published in print: Jun 2008
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