Measurement and Stochastic Computational Modeling of the Elastic Properties of Parallel Strand Lumber
Publication: Journal of Engineering Mechanics
Volume 135, Issue 9
Abstract
This paper describes a model for the spatial variation of the elastic modulus of parallel strand lumber (PSL) that is based on bending experiments and also describes a validated stochastic computational model that incorporates orthotropic elasticity and uncertainty in strand geometry and material properties. The PSL exhibits significant variability both within members and between members, but this variability is less than that of equivalent sawn-wood members, and decreases with increasing member size. The correlation length of the elastic modulus is found to be several meters and is independent of the cross-sectional size. The variance of PSL elastic modulus is found to scale inversely with the number of strands in the cross section. The validated computational model is flexible enough to allow preliminary exploration of the properties of new mixes of species and strand sizes in PSL material design.
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Acknowledgments
M. Peterson at the Wood Mechanics Laboratory provided valuable assistance in preparing test specimens and conducting the laboratory experiments. The National Science Foundation partially supported this work through Grant No. UNSPECIFIEDCMMI-0826265.
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Information & Authors
Information
Published In
Journal of Engineering Mechanics
Volume 135 • Issue 9 • September 2009
Pages: 897 - 905
Copyright
© 2009 ASCE.
History
Received: Apr 30, 2008
Accepted: Jan 12, 2009
Published online: Mar 6, 2009
Published in print: Sep 2009
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