Abstract

"Abstract: In general, data regarding the mechanical properties of wood is still incomplete, mainly owing to the difficulties involved in preparing well-made standard testing samples, as well as the time-consuming evaluation tests. Therefore, the elastic constants for Pinus radiata in this paper were determined using ultrasound technology. In parallel, typical compression mechanical testing was carried out to compare the effectiveness of the nondestructive test using the ultrasound. The longitudinal elastic constant values were similar to the mechanical testing (ultrasound was 12,8 % higher than mechanical testing), showing that ultrasound technique is a reliable and valid tool. The values for radial and tangential moduli obtained by the ultrasound versus mechanical testing showed statistically significant differences. This may be due to the difficulty in obtaining adequate samples for mechanical testing. The symmetry of the shear modulus was revealed by the ultrasound technique (Gij = Gji). Poisson's ratios were not comparable using either method; however, values obtained were more consistent with the existing literature for Pinus species. Additionally, the elastic anisotropy of the analyzed wood samples was demonstrated through the ultrasound velocity propagation in the material. It was thus possible to obtain the twelve engineering constants that characterize the mechanical behavior of wood employing of the proposed ultrasound technique. The results proved that this technique could be a useful tool for such characterization."