ABSTRACT Over the years, the species of eucalyptus has become a multipurpose raw material. In addition, the most relevant aspect of the use for various purposes is related to the production of a high quality wood, coming from short duration plantations, which is fundamental to the current demand of the industries. However, its use in civil construction has not yet reached a level of importance, due to the low knowledge of many of its resistance properties and the consequent popular fear in the use of reforestation woods, in particular the Eucalyptus grandis. This research investigated its main mechanical properties, aiming to reinforce its constructive applications in wood structures. For this, two physical properties and fourteen mechanical properties, in two different moisture conditions of the samples were evaluated, according to the norm NBR 7190 (1997). In the first moisture content, the samples were stabilized at 30%, while the second level considered the content of 12%. It was obtained 3580 determinations for the sixteen properties. From the 14 mechanical properties, only 7 had significant increases with the moisture reduction (30% to 12%), consisting of the rupture modulus in the parallel and normal compressions, normal traction and static bending; modulus of elasticity in normal compression and static bending and in shear strength.

ABSTRACT: Eucalyptus urophylla consists in a wood-producing species, which offers a natural multiple raw material of good quality for applications in rural and civil constructions. However, Eucalyptus urophylla still has a small utilization as building parts and elements, resulting from the possible ignorance and low diffusion of its structural possibilities. Thereby, the present research aims to measure the main thirteen mechanical properties of Eucalyptus urophylla wood for two different moisture contents, 12% and 30% (green wood). Furthermore, in these two conditions of moisture content evaluation, volumetric mass densities were also evaluated. At the end of this evaluation, which included 2688 determinations, all the obtained results were statistically treated with t-test at a 5% of significance level in order to evaluate the influence of moisture content in the evaluated properties. Twelve mechanical properties were significantly affected by moisture content, and the behavior pattern consisted in increasing the values of the properties with the reduction of the moisture content.