The Immediate Effect of Temperature on the Modulus of Elasticity of Green and Dry Lumber<sup>1</sup>
Keywords:Dry, green, MOE, moisture content, temperature change, lumber
AbstractThis study evaluated the immediate (reversible) effect of temperature on flexural modulus of elasticity (MOE) of green and dry nominal 2x4 (standard 38 by 89 mm) structural lumber from 66 to -26°C. For lumber at 4 and 12% moisture content (MC), a linear relationship was used to relate the increase in MOE to decreases in temperature. For green lumber, MOE also increased with decreasing temperature. A segmented linear regression was developed to describe the change in MOE of green lumber for 66 to -18°C. The slope of this relationship was steeper below 0°C than above. The actual MC of green lumber was not a factor above -18°C. Below this temperature, the increase in MOE with decreasing temperature was a function of both actual green MC and temperature. We discuss factors that cause this behavior in green wood at low temperatures and the use of an empirical model for describing the MOE-temperature relationship as a function of MC for frozen green lumber.
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