Investigation of FRP Lap Splice Using Epoxy Containing Carbon Nanotubes
Publication: Journal of Composites for Construction
Volume 19, Issue 2
Abstract
In many situations, it is necessary to splice multiple layers of fiber-reinforced polymer (FRP) composite laminates. The relatively low bond and shear strength of FRP layers usually necessitates long lap splices. In this paper, the authors demonstrate how lap splices shorter than those used in standard FRP design today can be made viable by incorporating carbon nanotubes in the epoxy resin. Experimental and numerical investigations are conducted to evaluate the significance of using multiwalled carbon nanotubes (MWCNTs) on FRP lap splice. Double lap shear joints of carbon-fiber-reinforced polymer (CFRP) were fabricated and tested with various amounts of functionalized MWCNTs (0.5, 1.0, and 1.5%). Experiments show that the shear stress-strain response of the CFRP lap splice can be engineered with the appropriate amount of MWCNTs to increase the bond strength by 50% and/or the failure strain by 300%. The numerical modeling shows that the shear-slip at the interface governs the bond strength and ductility of the lap joints.
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Acknowledgments
This work is funded by National Science Foundation (NSF) Award #1103601 to University of New Mexico and by U.S.-Egypt Cooperative Research Program through Science and Technology Development Fund (STDF) Grant # 3713 to EPRI, Egypt. The authors acknowledge this support.
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Information
Published In
Journal of Composites for Construction
Volume 19 • Issue 2 • April 2015
Copyright
© 2014 American Society of Civil Engineers.
History
Received: Nov 25, 2013
Accepted: Jun 23, 2014
Published online: Aug 5, 2014
Discussion open until: Jan 5, 2015
Published in print: Apr 1, 2015
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