Volume 26, Issue 2 (March 1998)
Mechanical Properties of Laminated Veneer Lumber via Five-Point Bending Test
The five-point bending test is shown to be an effective and efficient way of determining the mechanical properties of structural composite lumber. Shear strength, bending strength, shear-free Young's modulus of elasticity and shear modulus for both plank (flatwise) and joist (edgewise) orientations can be obtained with simple adjustments of the test configuration. Span or span-to-depth ratios are adjusted to produce either predominantly shear or bending failure. To determine elastic constants, a removable center support creates the necessary situation for both four-point bending and five-point bending. Use of a deflection yoke is especially important in determining the shear moduli. Results are reported for testing laminated veneer lumber. which was selected as representative of the evolving family of structural composite lumber products.