Caracterização de lenho de reação através da variação radial e longitudinal de propriedades físicas em madeira de eucalipto

Abstract

The reaction wood presents a great difference in its chemical, anatomical characteristics and physical properties in relation to the opposite wood. This heterogeneity of wood causes a series of problems for the transformation and processing industry. The present work aimed to study the physical properties of reaction wood and opposite reaction wood from a tree of the Eucalyptus genus. The tree was approximately 50 years old, coming from the Campus of the Federal University of Recôncavo da Bahia located in the city of Cruz das Almas – BA. To this end, specimens with dimensions of approximately 30x20x50 mm were removed from transverse discs to determine the basic densities and total linear contractions of the reaction wood, wood opposite the reaction wood, wood to the left of the pith and wood to the left of the pith. right side of the medulla. There was a statistically significant variation in density depending on the type of wood, with density being higher on the left and right of the pith. The reaction wood differed significantly from the opposite wood as it presented higher values ​​of tangential and volumetric contractions and anisotropy coefficient. Radial contraction did not vary depending on the wood strip, however, it showed a significant difference depending on the height in the trunk. Longitudinal contraction did not vary depending on the sources of variation under study. With these results, it was concluded that the formation of reaction wood can lead to wood heterogeneity due to the variation in its physical properties.