Effectiveness of a Novel Technique in Strengthening Web-Shear Capacity of Prestressed Hollow Core Slabs Using Externally Bonded FRP Sheets
Publication: Journal of Composites for Construction
Volume 21, Issue 1
Abstract
Precast, prestressed hollow-core (PHC) slabs are widely used in floor and roof decks because of their economic benefits. Because no shear reinforcement can be provided because of fabrication restraints, designers have to opt for deeper profile or filling PHC slab cores with concrete when the load demand exceeds the limited concrete shear capacity of PHC slabs. This research project is exploring an innovative technique for strengthening the web-shear capacity of PHC slabs by bonding external fiber-reinforced polymer (FRP) sheets along the internal perimeter of the slab voids. Experimental testing and numerical simulation on full-scale single web, I-shaped beam specimens cut out longitudinally from full-width hollow-core slabs have been performed during the first phase of this research to investigate the feasibility and effectiveness of this new technique. The influence of several design parameters, including the length and the width of the strengthened zone, the thickness of applied FRP sheets, and the prestressing level of PHC, have been investigated. Results show that once the minimum required strengthened zone length and FRP sheet thickness are satisfied, the proposed novel shear strengthening technique would provide a considerable enhancement on the shear capacity and ductility to the strengthened specimens.
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Acknowledgments
The authors wish to express their gratitude and sincere appreciation for the financial support received from the Natural Science and Engineering Research Council of Canada (NSERC) through the Engage program. The contribution made by the Prestressed Systems Inc. (PSI) and SIKA Canada for supplying experimental specimens and materials is gratefully acknowledged. The help received from the technical staff of the Structural Laboratory in the Department of Civil and Environmental Engineering at the University of Windsor is also acknowledged.
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Information & Authors
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Published In
Journal of Composites for Construction
Volume 21 • Issue 1 • February 2017
Copyright
© 2016 American Society of Civil Engineers.
History
Received: Oct 23, 2015
Accepted: Apr 11, 2016
Published online: Jun 8, 2016
Discussion open until: Nov 8, 2016
Published in print: Feb 1, 2017
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