Localized Tensile Strength and Modulus of Elasticity of E-Related Laminating Grades of Lumber


  • Brent A. Richburg
  • Donald A. Bender


MOE (modulus of elasticity), tensile strength, lumber, glulam, simulation, reliability


Localized modulus of elasticity (MOE) and tensile strength (T) of six E-rated grades and two visual grades of 2 by 6 Douglas-fir laminating lumber were measured over a test span of 2 ft. The E-rated laminating grades studied were C14, 2.3E-1/6, 2.3E-1/3, 2.0E-1/6, 2.0E-1/3, and 1.7E-1/4. The visual laminating grades were L2 and L3, which consisted of lumber not qualifying for the E-rated grades. Multivariate statistical parameters and probability distributions were fit to the localized MOE and T data. These parameters can be used to simulate lumber properties needed to predict the reliability of glued-laminated timber beams. Localized MOE and T data were simulated using a multivariate approach to determine whether the statistical properties of the original MOE and T data were preserved in the simulated data. The original statistical properties (i.e., probability distributions and correlations) were preserved in the simulated data for all lumber grades studied.


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Research Contributions