Variabilidade radial e longitudinal de propriedades da madeira de angico-vermelho (Anadenanthera peregrina (L.) Speg.) / Radial and longitudinal variability of properties of the wood of angico-vermelho (Anadenanthera peregrina (L.) Speg.)

AUTOR(ES)
DATA DE PUBLICAÇÃO

2008

RESUMO

The objective of this work was to determine the variability in the radial and longitudinal directions of some properties of the angico-vermelho (Anadenanthera peregrine (L.) Speg.) wood, from an area of native forest, located in the campus of the Universidade Federal de Viçosa, State of Minas Gerais, Brazil. The specific mass (basic and apparent), retractility, compression, shearing, Janka hardness and static bend mechanical resistance (MOR and MOE), were determined according to the norm NBR 7190 (ABNT, 1997) and ABNT MB-26 (1940) rule. The anatomical properties were determined according to the norm COPANT (1974) rule. Some dendrometrical variables associated with the logs were also evaluated. Seven trees were used, of unknown age, chosen at random in the field, with similar diameters at breast height (DBH). The results, by the Tukey test at 5% significance, showed that there an significant differences between the positions, in the pith-bark direction. These differences were observed among the logs, in the base-top direction, for the majority of the properties studied. A tendency of increase of the fibers length, on the wall thickness, on the basic and apparent specific mass, on the tangential retraction, radial retraction, on the volumetric retraction, on the compression resistance, on the shearing, on the hardness on the radial, tangential and cross sections, and on the rupture and elasticity modules on the radial direction, in the pith-bark orientation was observed. The fiber width and the lumen diameter showed a decrease in the same orientation. A clear tendency of variation in the radial direction, for the longitudinal retraction and for the anisotropic factor was not observed. A tendency of the decrease on the basic and apparent specific mass, on the compression resistance, on the shearing, on the hardness on the radial and cross sections was observed, as well as on the rupture and elasticity modules in the longitudinal direction, on the base-top orientation. A clear tendency of longitudinal variation, on the base-top orientation, for the fiber length, fiber width, lumen diameter, wall thickness, tangential retraction, radial retraction, volumetric retraction, longitudinal retraction, anisotropic factor and hardness on the tangential plane, was not observed.

ASSUNTO(S)

tecnologia e utilizacao de produtos florestais longitudinal variability propriedades da madeira angico-vermelho variabilidade radial anadenanthera peregrina wood properties variabilidade longitudinal radial variability

ACESSO AO ARTIGO

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