Mechanical Grading of Structural Larch Dimension Lumber

Abstract:

Larch dimension lumber bending strength properties from full-size bending test were used to establish preliminary grade boundary settings for mechanical grading of lumber by modulus of elasticity. Simulated production using the grade boundary settings were evaluated for modulus of rupture, ultimate tensile strength, and ultimate compressive strength. The results showed a good relationship between modulus of rupture and modulus of elasticity, and the observed relationships between strengths properties were consistent with that assumed for the standard grades. Through mechanical grading, larch dimension lumber could be sort grades: M14, M30 and M40. Assuming the visual requirements are met, the M30 and M40 grades account for more than 80% of the total production. Mechanical grading of larch appears to be a viable approach for grading Chinese large for structural applications.

• Periodical: Key Engineering Materials (Volume 517)
• Pages: 683-688
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.517.683
• Online since: June 2012
• Authors: Wan Li Lou, Hai Qing Ren, Zhao Hui Wang, Xiu Qin Luo
• Keywords: Bending Tests, Dimension Lumber, Grade Boundaries, Mechanical Grading

References

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DOI: 10.3403/00560921u

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