摘要
The variation in lumber quality within the supply of eucalypt is large. Effective segregation of the lumber according to "fitness for purpose " is fundamental to enabling the capture of greater value for the finger-jointed. This paper deals with the longitudinal vibration technique as a means of assessing modulus of elasticity (MOE) of solid and finger-jointed specimens made with Eucalyptus grandis × E. urophylla and E. grandis. Dynamic MOE was calculated from resonance frequencies obtained from longitudinal vibration. The dynamic MOE was well correlated to the static bending MOE for solid and finger-jointed lumber from the two eucalyptuses. Correlation coefficients were obtained for the regression of dynamic MOE on static bending MOE for solid and finger-jointed lumber, and were statistically significant. Although the correlation coefficient of finger-jointed was lower than that of solid lumber, the results indicated that the static bending MOE of finger-jointed was strongly correlated with the dynamic MOE of solid lumber, namely, the solid lumber with higher dynamic MOE can produce higher bending MOE finger-jointed. It can be concluded that the longitudinal vibration technique may be useful as a nondestructive method for segregating lumbers for finger-jointed.
The variation in lumber quality within the supply of eucalypt is large. Effective segregation of the lumber according to "fitness for purpose " is fundamental to enabling the capture of greater value for the finger-jointed. This paper deals with the longitudinal vibration technique as a means of assessing modulus of elasticity (MOE) of solid and finger-jointed specimens made with Eucalyptus grandis × E. urophylla and E. grandis. Dynamic MOE was calculated from resonance frequencies obtained from l...
基金
This research is supported by ITTO Project PD 69/01 Rev. 2 (I) " Improved and diversified use of tropical plantation timber in Chinato supplement diminishing supplies from natural forests" .