Orthotropic behavior of lumber composite materials

Elasticity properties were evaluated with respect to the various commercial types of composite lumber. The study included laminated veneer lumber (LVL), parallel strand lumber (PSL), and laminated strand lumber (LSL). The experimental study was designed to better characterize the elasticity properties of these increasingly important structural composite lumber (SCL) materials. Experimental efforts for SCL material characterization were performed applying the five-point bending test (FPBT) and torsional stiffness measurement test (TSMT) evaluation methodologies. FPBT provided simultaneous solution for both modulus of elasticity (E) and modulus of rigidity (G). TSMT was employed to derive both the in-plane and through-the-thickness shear moduli from a singular test scheme. Further investigation focused on axial tests under tensile and compressive loading conditions for determinations of longitudinal and transverse elastic moduli (i.e., E₁ and E₂) combined with in-plane Poisson ratio (ν₁₂). Presented are the descriptive statistics of the SCL elasticity data as are comparisons to the orthotropic behavior of solid wood.