Flexural Strength of Posttensioned Timber Beams
Publication: Journal of Composites for Construction
Volume 18, Issue 2
Abstract
An experimental program was conducted at the University of Manitoba to test salvaged timber stringers posttensioned with external carbon fiber–reinforced polymer (CFRP) bars or steel guy cables. A total of 22 creosote-treated Douglas-fir beams with dimensions of were tested in three-point bending. Six beams out of the 22 were control beams without any reinforcement. The remaining 16 beams were posttensioned using different reinforcement configurations. Four beams were posttensioned with draped CFRP tendons (Group CD), four beams were posttensioned with straight CFRP tendons (Group C), four beams were posttensioned with draped steel cable (Group SD), and four beams were posttensioned with straight steel cable (Group S). The experimental results found that the strength and the stiffness for Group CD were increased on average by 70% and 10%, respectively, while the strength for Group C was increased on average by 56% and showed no significant increase in stiffness. In contrast, the strength and the stiffness for Group SD were increased on average by 45% and 4%, respectively, while the strength for Group S was increased on average by 49% and showed no significant increase in stiffness.
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Acknowledgments
The timber beams used in this research were provided by Ministry of Transportation Ontario. Strengthening the beams for shear was completed by Vector Construction Group, Winnipeg, Manitoba. The authors would like to thank Mr. Garth Fallis from Vector Construction Group for his valuable input in design of the anchors. The financial support provided by Manitoba Infrastructure and Transportation and ISIS Canada Resource Centre is gratefully acknowledged. The authors would like to thank the staff of the W. R. McQuade Structures Laboratory at the University of Manitoba for their help during testing.
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Information & Authors
Information
Published In
Journal of Composites for Construction
Volume 18 • Issue 2 • April 2014
Copyright
© 2013 American Society of Civil Engineers.
History
Received: Mar 6, 2013
Accepted: Aug 5, 2013
Published online: Oct 30, 2013
Discussion open until: Mar 30, 2014
Published in print: Apr 1, 2014
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