Bending Properties of Wood I-Sections Fabricated with Screws and Polyurethane Adhesive
Publication: Journal of Structural Engineering
Volume 139, Issue 11
Abstract
Laboratory tests were used to quantify the effects of section shape, screw density, and polyurethane adhesive use on laminated wood assembly bending strength and stiffness. Both I-shaped sections and vertically laminated rectangular sections were studied, each utilizing three members. I-sections featured dimension lumber flanges screwed to laminated strand lumber (LSL) webs. In half of these assemblies, polyurethane adhesive was used in addition to screws. Only screws and dimension lumber (no LSL or adhesive) were used in fabrication of the vertically laminated assemblies. Bending strength and stiffness were significantly increased by the reconfiguration of members into an I shape. Composite action, and therefore bending strength and stiffness, was significantly increased by the addition of polyurethane adhesive to I-sections. This research presents an efficient assembly design with bending strength and stiffness values significantly higher than those of the current industry standard mechanically laminated assembly.
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Acknowledgments
Research was supported by a Hatch Act Formula Grant through the University of Wisconsin, Madison.
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Information
Published In
Journal of Structural Engineering
Volume 139 • Issue 11 • November 2013
Pages: 2019 - 2027
Copyright
© 2013 American Society of Civil Engineers.
History
Received: Jul 9, 2012
Accepted: Nov 5, 2012
Published online: Nov 7, 2012
Published in print: Nov 1, 2013
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