Determining Shear Modulus of 3-ply Laminated Veneer Lumber by Uniaxial Tension Test

  • Received : 2013.07.22
  • Accepted : 2013.09.23
  • Published : 2013.09.25


Estimation equations of shear modulus in the plane of laminated veneer lumber (LVL) were compared each other through uniaxial tension test results. The equations - basic elastic equation in the dimensional orthotropic case, Hankinson's formula and empirical equation proposed by Salikis and Falk, were applied to determine the elastic constants at various angles to the grain, which were needed for determination of shear modulus. Tensile elastic modulus of LVL predicted from these equations were compared with test data to evaluate the accuracy of the equation. Tensile elastic modulus rapidly decreased at orientations between 0 and 15 degrees and elastic modulus at grain angles of 15, 30, and 45 degrees overestimated in the presented equations. But the proposed equation by Salikis and Falk showed better prediction, especially at 30, and 45 degrees. This proposed formula would be more useful and practical for estimating of shear modulus of wood composites like LVL to minimize the effect of Poisson's ratio term.


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