Resistência mecânica de caules de clones de Eucalyptus cultivados em diferentes topografias

Abstract

The objective of this work was to evaluate the failure moment of the stem from trees and its relationship with the basic density, volumetric shrinkage, modulus of elasticity in static bending and modulus of rupture. The mechanical resistance of the trees was determinate trying to simulate the wind action on them, measuring the necessary strength to produce the rupture of the tree or their permanent deformation. For the trees of the four clones it can be concluded that: i) the average height of rupture was equal to 2.5 m; the average force of rupture was equal to 69.6 kgf; the modulus of the rupture was 464.1 kgf.cm-2; ii) the average rupture force increased with the land slope; while the modulus of the rupture presented itself higher for slight slope than for heavy slope or flat land; iii) clone 129 stands out as the most strong; iv) several associations between the modulus in the rupture and the characteristics of wood were identified. The most evident was the volumetric shrinkage, which is related inversely with the modulus in the rupture.