Caracterización nanomecánica de la estructura celular y anatómica de Eucalyptus nitens y su relación con la frecuencia de grietas y rajaduras en madera redonda

Abstract

The aim of this study was to define the minimum volumen in trees of E. nitens that characterize the mechanical and anatomy behavior for non-destructive sampling. The trees were cut from sites located in Mulchen and Yungay in the region of Bío Bío. Relationships were found between nanomechanical properties, wood anatomy and wood cracks and fractures. The response variables were the ductility ratio (E/H) and the modulus of resilience (ur), in the S2 layer and middle lamella. The results showed that the representative volume, from E. nitens families is at 3 meter high from base of the trees and between the 5th to 7th annual rings. Also, it was established that the middle lamella is more brittle than the S2 layer. Relationship between the vessels morphology and the level of the wood cracking was observed. A high area of vessels, a high vessel diameter and a small frequency of them, resulted in high cracking. The cracks were mainly concentrated in the first meters of tree, were we found a good relationship of this response variable with the E/H ratio for the middle lamella; there was a significant change of this ratio at 3 meters high. Cracks were evident on earlywood and from the 5th to the 7th annual rings. (English) [ABSTRACT FROM AUTHOR]