Outdoor aging of wood-based panels and correlation with laboratory aging : Part 2

Abstract

The performance of four commercially manufactured structural wood-based panels and three ply woods was determined in accelerated laboratory-aging treatments and outdoor exposure. The wood-based panels met the ANSI/A208. 1-1989 standards for modulus of rupture (MOR) of 2-M-2 particleboard. Performance of the wood-based panels was severely decreased by accelerated laboratory-aging treatments, including the cyclic boil-dry treatment and the ASTM D 1037 accelerated-aging treatment. Woodbased panels did not meet the ANSI A208. 1 bond durability requirement for MOR after undergoing ASTM D 1037 accelerated-aging treatment. Performance of the wood-based panels after aging was considerably below that of two lower ranking wood-based panels from a previous study. Outdoor aging for 1 year reduced MOR and modulus of elasticity of wood-based panels by 38 to 59 percent. Internal bond strength decreased 34 to 60 percent; panel thickness increased 11 to 18 percent after 1 year of outdoor exposure. Performance of the three plywoods was comparable to that of the exterior marine plywood tested previously. A relationship was developed between the MOR after 1 year of outdoor exposure and after five boil-dry cycles. This relationship was compared with a similar relationship developed previously for a broad range of exterior-type panel materials. The new relationship appears to coincide and strengthen the relationship developed in the previous study.