ReLAM: Nonlinear Probabilistic Model for the Analysis of Reinforced Glulam Beams in Bending
Publication: Journal of Structural Engineering
Volume 138, Issue 6
Abstract
The University of Maine, in conjunction with Willamette Industries, Georgia-Pacific, Strongwell, and APA—the Engineered Wood Association, tested 90 fiber-reinforced polymer (FRP)-reinforced glue-laminated wood (glulam) beams. This study showed that a FRP reinforcement ratio of 3% in tension can increase glulam-allowable bending stress () by more than 100%. Furthermore, this physical testing was used to verify a nonlinear probabilistic computer model for reinforced glulam, called the reinforced laminated (ReLAM) model. ReLAM uses moment-curvature () analysis and Monte Carlo simulation to predict the strength and stiffness of a population of reinforced glulams, requiring as input distributions of the lamstock long-span flatwise-bending modulus of elasticity (), ultimate tensile stress, and ultimate compressive stress. ReLAM output lists the reinforced glulam modulus of elasticity (MOE) and in terms of the gross cross-sectional dimensions, providing beam properties in the same fashion as the current tabulated properties for unreinforced glulams. ReLAM accurately predicted the and MOE for the 90 reinforced glulams tested, demonstrating that it is a valuable tool for the analysis of reinforced glulams with various layups, reinforcing materials, and reinforcing levels.
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Information & Authors
Information
Published In
Journal of Structural Engineering
Volume 138 • Issue 6 • June 2012
Pages: 777 - 788
Copyright
© 2012. American Society of Civil Engineers.
History
Received: Oct 11, 2010
Accepted: Aug 19, 2011
Published online: Aug 22, 2011
Published in print: Jun 1, 2012
Published ahead of production: Jun 15, 2012
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