Simplified Model for Strength Assessment of Timber Beams Joined by Bonded Plates
Publication: Journal of Materials in Civil Engineering
Volume 25, Issue 8
Abstract
This paper presents a simplified method of analysis and design for repair using bonded rigid plates of timber beams with localized damage. This method assesses the load-bearing capacity of the connection between plate and timber and proposes two failure modes: shear stresses at the bonding interface and in the timber piece. An experimental campaign was developed to verify the theoretical model, which in this paper is limited to the problem of bending moment transfer. Ten specimens of Pinus radiata D. Don were joined with bonded-in plates and 10 with laterally bonded ones, after which they were tested for bending. Two epoxy formulations were used as adhesive and glass fiber–reinforced plastic (GFRP) plates for reinforcements. Tests with different anchorage lengths were developed to establish a relationship with load-carrying capacity. For an anchorage length approximately longer than twice the depth of the plate, failure was not located at the connection. There was reasonable agreement between the theoretical and experimental results. The former were always on the safe side, and there was better agreement in the case of laterally bonded plates.
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Acknowledgments
The author gratefully acknowledges the support of the Timber Industry Technical Research Association (Asociación de Investigación Técnica de las Industrias de la Madera), the Ministry of Culture (Ministerio de Cultura), and the Ministry of Science and Innovation, BIA2010-18858. The testing materials were supplied free of charge by Sika adhesives and the GFRP composite materials by the Bremen company.
References
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Information & Authors
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Published In
Journal of Materials in Civil Engineering
Volume 25 • Issue 8 • August 2013
Pages: 980 - 990
Copyright
© 2013 American Society of Civil Engineers.
History
Received: Oct 26, 2011
Accepted: Aug 16, 2012
Published online: Aug 24, 2012
Discussion open until: Jan 24, 2013
Published in print: Aug 1, 2013
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