Behavior of Split Timber Stringers Reinforced with External GFRP Sheets
Publication: Journal of Composites for Construction
Volume 12, Issue 2
Abstract
A large number of timber bridges are at the end of their service life in North America and the prohibitive costs of replacement make owners face the challenge of developing efficient rehabilitation techniques. This paper presents the results from an experimental program of testing old full scale timber stringers with longitudinal splits. Stringers were reinforced for shear and bending using glass fiber-reinforced polymer (GFRP) sheets. A total of nine full-scale Douglas-fir beams were tested in three-point bending after strengthening for flexure and shear with GFRP sheets. Horizontal shear forces in shear reinforcement were calculated using a simplified model. Beams that failed by debonding of shear reinforcement, failed at horizontal shear forces within the range of . Design charts were constructed on the basis of these calculated forces to simplify the design of shear reinforcement for different sizes and locations of splits.
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Acknowledgments
The writers wish to acknowledge the support from ISIS Canada Network of Centres of Excellence, Bridges and Structures Branch of Manitoba Transportation and Government Services for providing the test specimens, and Vector construction group for strengthening the beams. The staff of W.R. McQuade Laboratory and graduate students of the University of Manitoba are also gratefully acknowledged.
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Information
Published In
Journal of Composites for Construction
Volume 12 • Issue 2 • April 2008
Pages: 202 - 211
Copyright
© 2008 ASCE.
History
Received: Jun 12, 2006
Accepted: Apr 30, 2007
Published online: Apr 1, 2008
Published in print: Apr 2008
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