Evaluation of the Tensile Modulus of Elasticity in Parallel Direction to the Grain for Eucalyptus grandis Wood Specie

Abstract

This research aimed to present an alternative methodology to determine the tensile modulus of elasticity based on the least squares method, allowing multiple uses of load and displacements values obtained from the experiment, giving greater reliability in the calculation of timber stiffness. Were used twelve specimens of Eucalyptus grandis wood species, tested in tensile parallel to the grain according to the assumptions of the Brazilian standard ABNT NBR 7190:1997. The modulus of elasticity obtained from the proposed calculation approaches were compared with the elastic moduli obtained from Brazilian standard recommendations. Results of analyzes of variance (Kruskal-Wallis) showed statistical equivalence between the modulus of elasticity obtained for both forms of calculation. However, considering the non-homogeneity of wood, to generalize the conclusions, it is necessary new set tests involving all strength classes indicate by NBR 7190:1997.