Three hardwoods technological properties characterization deteriorated by termites

ABSTRACT The objective of this study was to determine technological properties of Corymbia maculata. Eucalyptus dunnii and Eucalyptus saligna forest species, and to verify the changes in the characteristics of these Woods after food preference assay with Nasutitermes termites. The food preference assay was conducted through of the standard ASTM D 3345 (2008) adapted, evaluating the mass loss and mechanical properties at the end of the corresponding period. To obtain the results, the basic specific mass (μEB) was analyzed, with the aid of standard ASTM D 143 (2014), Janka hardness in the tangential and radial planes and the elasticity modulus (EC) and compression resistence (FC), both obtained by the compression parallel to grain test, before and after the termites attack. About the technological properties, it was verified that the Corymbia maculata species had the highest μEB (0.674 g/cm3) and mechanical resistance, with the highestvalues of Janka hardness in both anatomical planes (tangential = 664.6 kgf/cm2, radial = 593.8 kgf/cm2) and parameters related to compression parallel to grain (EC = 294.873 kgf/cm2, FC = 667.7 kgf/cm2). After the Nasutitermes termites test, the greatest mass loss was observed in the Eucalyptus dunnii species, thus indicating its food preference. These caused insignificant decreases in the mechanical properties, when compared to those measured before the food preference assay. From the results obtained, it is concluded that the wood deterioration by Nasutitermes, together with the anatomical characteristics, caused variations in the technological properties analyzed, however, the species Eucalyptus saligna and Corymbia maculata showed high natural resistance in relation to the termites.