Deterioration of black wattle wood in two exposure environments

Abstract

Advanced stages of deterioration have a critical effect on the mechanical properties of wood. This study aimed to use the mechanical bending test as a parameter for assessing the deterioration of the wood of Acacia mearnsii in different environments. The experiment consisted in two fields of rot in the northern region of the State of Rio Grande do Sul: environment 1 (open field) and environment 2 (seasonal deciduous forest), with seven samples in each, where they stayed for 12 months. After the period were made the specimens to the bending test in order to compare with those of unexposed samples. Was also performed a survey of the soil and climate characteristics of the areas for better understanding of the results. Both fields have indicated a significant reduction in the studied variables (MOE, MOR, σLP) in relation to the control. When evaluated the two environments, the contrast was significant only for the modulus of elasticity, at the other properties there was no significant influence of environments, the forest produced the greatest reductions in mechanical bending the wood of black wattle, related to the environment characteristics.