Destructive and Nondestructive E-Rating of Red Maple Veneers

Abstract In this study, the modulus of elasticity of red maple ( Acer rubrum ) veneer, a native species abundant in eastern North America, was evaluated. These veneer sheets were 3.5 mm thick by 304 mm wide by 2.44 m long. Over 500 specimens were visually graded and subjected to a nondestructive stress wave test to determine the dynamic modulus of elasticity (MOE d ). Subsequently, 60 specimens were selected for tensile testing to measure the static modulus of elasticity (MOE s ). The average MOE d was 19.10 GPa, while the MOE s obtained from tensile testing was 11.88 GPa. This tension-based MOE value was very close to the bending test value for red maple lumber reported in the wood handbook (11.31 GPa). A regression analysis was conducted to evaluate the effects of density and defects on MOE. The results showed that density has a greater effect on MOE d than defects. A correlation was also developed between MOE d and MOE s . The results showed that the MOE d was 60 percent higher than the MOE s , with a weak positive correlation ( r = 0.40). The stress wave velocity, as affected by different factors such as density, defects, and fiber orientation, strongly correlated with MOE d .