The Influence of Rays on the Transverse Elastic Anisotropy in Green Wood of Deciduous Trees

Abstract

Summary The green wood of twelve deciduous tree species was investigated regarding its radial and tangential moduli of elasticity measured in tension (ER and ET, respectively). In addition, the wood density and the volume fraction of rays were determined. A strong positive correlation was found between structural and stiffness properties. A simple two component model was derived for the relationship between the transverse elastic anisotropy factor (i.e., ER/ET) of the green wood and the relative volume fraction of the axial and ray tissues. In the radial direction of the wood, the modulus of elasticity is influenced by the wood density and the volume fraction of rays; in tangential direction only the density seems to be important. However, the comparison between the elastic anisotropy and the volume fraction of rays indicates that the rays may have an indirect influence due to their shape.