Experimental Testing of CFRP-Strengthened Reinforced Concrete Slab Elements Loaded by Close-In Blast
Publication: Journal of Structural Engineering
Volume 140, Issue 2
Abstract
Strengthening reinforced concrete slab or wall structural elements with carbon fiber-reinforced polymer (CFRP) can improve their blast resistance. However, close-in blasts (blasts with a scaled range of less than ) may undermine the effectiveness of the CFRP strengthening. This paper presents an experimental testing program on CFRP-strengthened reinforced concrete slab specimens that utilized fiber anchors. Two CFRP mitigation designs were tested under blast loads with a scaled range of 0.4 and . Tests on unmitigated reinforced concrete slab specimens provided baseline comparisons. The experimental results showed that the use of CFRP strengthening improved the blast resistance of reinforced concrete slab specimens. For a larger scaled range, , the CFRP successfully prevented flying debris and reduced the overall deflections of the slab specimens. However, for the closer scaled range, , the high shock blast pressures shattered the concrete through the thickness of the slab specimen and tore through the back-face CFRP. However, back-face velocity and overall deflections were reduced by about 75% compared to the baseline test slab specimen.
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Acknowledgments
This research effort was supported by the Science and Technology Directorate of the Department of Homeland Security. Permission to publish was granted by the Department of Homeland Security and the Director, Geotechnical & Structures Laboratory.
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Published In
Journal of Structural Engineering
Volume 140 • Issue 2 • February 2014
Copyright
© 2013 American Society of Civil Engineers.
History
Received: Apr 9, 2012
Accepted: Feb 6, 2013
Published online: Feb 9, 2013
Published in print: Feb 1, 2014
Discussion open until: Mar 21, 2014
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