Flexure of Two-Way Slabs Strengthened with Prestressed or Nonprestressed CFRP Sheets
Publication: Journal of Composites for Construction
Volume 12, Issue 4
Abstract
This paper presents a study on the flexural behavior of two-way reinforced concrete slabs externally strengthened with prestressed or nonprestressed carbon fiber-reinforced polymer (CFRP) sheets. Four large-scale flat plate slabs are tested and a nonlinear three-dimensional finite-element analysis is conducted to predict the flexural behaviors of the tested slabs, including the load-deflection response, strain distribution, crack propagation, and crack mouth opening displacement. An increase in the load-carrying capacity of 25 and 72% is achieved for the slabs strengthened with nonprestressed and prestressed CFRP sheets, respectively, in comparison to the unstrengthened slab. A reduction of the deflections up to 32% in service is noted for the strengthened slabs. The unstrengthened slab shows very ductile behavior, whereas, progressive failure is observed for the strengthened slabs, exhibiting pseudoductility in postpeak behavior. Stress redistribution between the internal and external reinforcement is significant in the slab strengthened with prestressed CFRP sheets.
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Acknowledgments
The writers wish to acknowledge the support of the Department of National Defense (DND) of Canada through the Military Engineering Research Group (MERG) at the Royal Military College of Canada. The financial support from the Intelligent Sensing for Innovative Structures Network (ISIS Canada) and Queen’s University are also acknowledged. The contribution of D. Gaskin, O. Rielo, and L. Bizindavyi is also appreciated.
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Information & Authors
Information
Published In
Journal of Composites for Construction
Volume 12 • Issue 4 • August 2008
Pages: 366 - 374
Copyright
© 2008 ASCE.
History
Received: Jul 5, 2006
Accepted: Aug 27, 2007
Published online: Aug 1, 2008
Published in print: Aug 2008
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