Prediction of Bending Strength in Oak Beams on the Basis of Elasticity, Density, and Wood Defects
Publication: Journal of Materials in Civil Engineering
Volume 24, Issue 6
Abstract
The purpose of the study was to propose accurate models for predicting bending strength that are valid for a wide range of beam qualities. For the study, 26 European oaks (Quercus robur L.) were felled in northwestern Spain, where most of the oak stands in the country are located. The trees were sawn, and a sample of quarter-sawn planks was selected. Planed and edged specimens () were tested to obtain the modulus of rupture (MOR) in axial direction bending, the modulus of elasticity (MOE), density, moisture content, and size of defects. The MOR was correlated with the MOE and with maximum edge knot diameter. The correlation was not high enough to justify construction of a predictive model of mechanical behavior on the basis of maximum knot size in the piece. The analyses enabled development of a model for predicting MOR, with MOE as the only predictor variable (; ).
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Acknowledgments
We thank the Xunta de Galicia and the Research Office of the Universidad de Santiago de Compostela for providing financial support for the project.
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Published In
Journal of Materials in Civil Engineering
Volume 24 • Issue 6 • June 2012
Pages: 629 - 634
Copyright
© 2012. American Society of Civil Engineers.
History
Received: Jul 2, 2010
Accepted: Nov 14, 2011
Published online: Nov 16, 2011
Published in print: Jun 1, 2012
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