Post-Fire Behavior of GFRP Bars and GFRP-RC Slabs
Publication: Journal of Materials in Civil Engineering
Volume 30, Issue 3
Abstract
Technologies developed over the last two decades have introduced the use of glass fiber reinforced polymer (GFRP) composite bars as reinforcement in concrete structures when corrosion of the steel reinforcement is likely to occur. Fire resistance of GFRP-reinforced concrete (RC) members is a potential concern that needs to be understood and addressed because of the susceptibility of GFRP bars to degradation at elevated temperatures. In this study, the residual strength of fire-exposed GFRP-RC slabs and the GFRP mechanical properties after furnace exposure were studied. Slabs reinforced with two different types of GFRP bar were exposed to a furnace fire and sustained three-point bending, simulating the sustained service load (the moment due to dead load plus 20% of the moment due to live load at midspan), for 2 h. Upon completion of the fire test, the residual slab strength was assessed using a quasi-static flexural test up to failure. Next, GFRP bars were extracted from the selected locations of the slabs to evaluate the residual mechanical properties, including shear strength (transverse and horizontal) and glass transition temperature (). The GFRP-RC slabs with both bar types did not experience apparent reduction in flexural capacity after a 2-h fire test that generated a maximum temperature of 115°C at the bar surface. The GFRP transverse shear strength decreased whereas the horizontal shear strength and slightly increased.
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Acknowledgments
The authors gratefully acknowledge the National Science Foundation (NSF) and its industrial members for the support provided to the Industry/University Center for Integration of Composites into Infrastructure (CICI) at the University of Miami under Grant No. NSF IIP-1439543.
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Information & Authors
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Published In
Journal of Materials in Civil Engineering
Volume 30 • Issue 3 • March 2018
Copyright
©2017 American Society of Civil Engineers.
History
Received: Mar 21, 2017
Accepted: Aug 22, 2017
Published online: Dec 20, 2017
Published in print: Mar 1, 2018
Discussion open until: May 20, 2018
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