Calculations of Shear Moduli of Three-Ply Cross-Laminated Wood Panels from Shear Moduli of Individual Laminae
Keywords:Cross-laminated panel, shear modulus, apparent MOE, shear force, deflection
AbstractTo study in detail the effect of deflection caused by shear force of cross-laminated panels, shear modulus, apparent modulus of elasticity (MOE), and deflection caused by shear force of cross-laminated panels with different component ratios of laminae thicknesses were investigated using the equation derived for calculating shear modulus of a three-ply laminated beam from the shear moduli of individual lamina. The calculated shear modulus for C⊥ type increased markedly with increasing core laminae thickness, and that for C∥ type decreased markedly with increasing core laminae thickness. Also, the calculated shear modulus for C⊥ (45) type was higher than that for C⊥ (90) type at every core laminae thickness, whereas the calculated shear modulus for C∥ (45) was higher than that for C∥ (90) type at every core laminae thickness. The calculated value of the apparent MOE showed good agreement with measured value, and it was found that the apparent MOE can be calculated from true MOE and shear moduli of lamina. The percentage of deflection caused by shear force (Ysc) calculated from the calculated apparent MOE was close to that (Ys) calculated from the measured apparent MOE. From these results, the validity of the derived equation for calculating shear moduli of laminated panels from individual lamina was proven once more.
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