Investigation of some modulus properties of rubberwood by means of bending test
Abstract
The aim of this study was to investigate some modulus properties (Shear modulus (G), modulus of elasticity (MOE) and true modulus of elasticity in longitudinal direction (EL)) of rubberwood by means of bending test. The comparison of the obtained result with ones obtained by using different testing methods reported elsewhere was also made. The bending test was conducted in accordance with ASTM D198 and ASTM D 143 standards. Effect of annual ring orientation on the examined properties was considered. In addition, effect of span length to thickness ratio (L/t) on MOE value was also examined. The result showed that annual ring orientation did not affect MOE values but slightly affected G value. Shear modulus in radial-longitudinal plane (GRL) was about 1.34 times higher than shear modulus in tangential-longitudinal plane (GTL). However, it was found that the shear modulus obtained from this study was lower in comparison with ones determined by using different testing methods reported in literature. Notably, MOE value was decreased with decreasing L/t ratio. Finally, the relationship between MOE/EL and span length to thickness ratio was finally achieved.References
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