Abstract
In Brazil, the Brazilian Standard NBR 7190 (ABNT, 1997ASSOCIAÇÃO BRASILEIRA DE NORMAS TÉCNICAS. NBR 7190: projeto de estruturas de madeira. Rio de Janeiro, 1997.) establishes testing methods to obtaining the physical and mechanical properties wood. With the impossibility of determining the experimental results, the Brazilian Code establishes relations among the properties. However, the relations between the stiffness properties are based on the older normative standard MB-26: 1940 (Brazilian Standard NBR 6230), which condisidered another calculation model rather than the one used by the Brazilian standard. This research aimed to investigate the equivalence between the conventional modulus of elasticity in static bending tests (EM), with compression parallel to the fibres (Ec0) and tension parallel to the fibres (Et0) of ten species of tropical wood, as well as to establish relations between these properties, in case they are not equivalent. The ANOVA results showed that Ec0 and Et0 were statistically equivalent, and the relation between EM and 0.90∙Ec0 was not statistically equivalent, implying the determination of an ideal coefficient equal to 0.98 by the least squares method. This coefficient was 8.89% higher than the Brazilian standard.
Keywords:
Relations between properties; Hardwood; Stiffness; Beams theory
