Compression Splices of GFRP Bars in Unconfined and Confined Concrete Columns
Publication: Journal of Composites for Construction
Volume 23, Issue 6
Abstract
Although the use of glass fiber–reinforced polymer (GFRP) bars as compression reinforcement in RC columns has been extensively investigated, no research has been conducted on spliced GFRP bars under compression. This study presents an experimental program aimed at providing more insight into the effects of confinement on the behavior of spliced GFRP bars under compression. The test variables were confinement and compression-bar splice length. The test matrix included 14 circular concrete columns that were tested under concentric compression loading. Nine of the specimens were confined with GFRP spirals at two different spacings (40 and 80 mm), whereas the rest were reinforced longitudinally without transverse reinforcement. The test results are presented and discussed in terms of load–displacement behavior, failure mode, splice strength, and load–strain behavior. The postpeak behavior of the columns improved significantly with increasing levels of confinement. The bond and end-bearing contributions are described in detail. A regression analysis of the experimental results is presented, along with an analytical model proposed for predicting the strength of spliced GFRP bars under compression. The model estimates splice strength with satisfactory accuracy.
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Acknowledgments
The authors express their special thanks and gratitude to the Natural Science and Engineering Research Council of Canada (NSERC), the Canada Research Chair in Advanced FRP Composite Materials for Civil Structures, the NSERC Research Chair in FRP Reinforcement for Concrete Infrastructure, the Fonds de la recherche du Québec en nature et technologies (FRQ-NT), Mathematics of Information Technology and Complex Systems (MITACS), the Canadian Foundation for Innovation (CFI), and the technical staff of the structural lab in the Department of Civil Engineering at the University of Sherbrooke.
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Published In
Journal of Composites for Construction
Volume 23 • Issue 6 • December 2019
Copyright
©2019 American Society of Civil Engineers.
History
Received: Jul 5, 2018
Accepted: Mar 28, 2019
Published online: Sep 14, 2019
Published in print: Dec 1, 2019
Discussion open until: Feb 14, 2020
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