Effectiveness of GFRP Sheets for Shear Strengthening of Timber
Publication: Journal of Composites for Construction
Volume 10, Issue 6
Abstract
The objective of this study was to develop a cost-effective shear-strengthening technique for timber stringers that is environmentally friendly and leads to a durable structure. Testing was performed on creosote-treated Douglas fir beams, with dimensions of , removed from a 40 year old bridge. Two strengthening schemes were investigated; incorporating vertical and diagonal glass fiber-reinforced polymer (GFRP) sheets applied to both shear spans. The diagonal scheme proved effective in increasing the average ultimate load, flexural stiffness, and deformability of the beams. Performance of the members reinforced using the vertical scheme, however, was poor compared to diagonally reinforced beams. The contribution of the diagonal sheets to the shear capacity of the stringers was around 12% at service loads and 40% at ultimate load. In conclusion, this study has shown that diagonal GFRP sheets are more effective than vertical sheets in shear-strengthening timber stringers with horizontal splits at their ends.
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Acknowledgments
The writers wish to acknowledge the support of the Bridges and Structures Branch of Manitoba Transportation and Government Services, ISIS Canada, Vector Construction Group, and the Faculty of Architecture for the use of their facilities, and lab technicians from the W. R. McQuade Laboratory.
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Information & Authors
Information
Published In
Journal of Composites for Construction
Volume 10 • Issue 6 • December 2006
Pages: 483 - 491
Copyright
© 2006 ASCE.
History
Received: Oct 11, 2004
Accepted: Jan 6, 2006
Published online: Dec 1, 2006
Published in print: Dec 2006
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