Benefits of Grooving on Vacuum-Assisted Resin Transfer Molding FRP Wet-Out of RC Beams
Publication: Journal of Composites for Construction
Volume 17, Issue 5
Abstract
Fiber-reinforced polymer (FRP) externally bonded to RC beams is commonly applied by hand layup. Vacuum-assisted resin transfer molding (VARTM), a novel application method in infrastructure, can produce FRP with more-consistent quality and uniformity. Additional steps are required, however, which can increase the application time and cost. This research will investigate the reduction of VARTM wet-out time achieved by sawing grooves into the concrete surface. Fiber-reinforced polymer U-jackets are applied by VARTM to beams with vertical grooves. The wet-out of the beams is recorded and timed. Results indicate that beams with 3.2-mm-deep grooves achieve 95% wet-out in an average of 200 s. This is only 22% of the time it takes to wet-out a beam with no grooves, an average of 911 s. A wet-out mechanism based on a modified Darcy’s law is presented to verify the results. Darcy’s law predicts that time savings increase exponentially with the length that the epoxy has to travel, which indicates that a significant amount of time could be saved on actual girders.
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Acknowledgments
The authors gratefully acknowledge funding and support provided by Alabama Department of Transportation (ALDOT) Research Project 930-607B under the guidance of bridge engineers Fred Conway and George Connor.
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Published In
Journal of Composites for Construction
Volume 17 • Issue 5 • October 2013
Pages: 636 - 640
Copyright
© 2013 American Society of Civil Engineers.
History
Received: Sep 10, 2012
Accepted: Jan 18, 2013
Published online: Jan 21, 2013
Discussion open until: Jun 21, 2013
Published in print: Oct 1, 2013
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