Ultrasound to estimate the physical-mechanical properties of tropical wood species grown in an agroforestry system

Abstract

The great diversity of tropical wood species makes it difficult to obtain information about their technological properties. The present work employed ultrasound to estimate the physical and mechanical properties of four wood species: African mahogany (Khaya senegalensis), ‘freijó’ (Cordia goeldiana), ‘paricá’ (Schizolobium amazonicum), and teak (Tectona grandis). Nineteen-year-old adult trees were selected and harvested from an agroforestry system (AFS) located in the Brazilian Amazon. From the harvested trees, 1.5 m logs were sawn and test specimens were obtained for physical-mechanical assays. The ultrasound propagation speed (V 0) and the dynamic modulus of elasticity (E d ) were obtained from applying ultrasound longitudinally in wood samples. Values of V 0 decreased from the lightest wood (paricá) to the heaviest (African mahogany), and E d presented the opposite behavior. For the physical properties, the coefficient of determination (R 2) ranged from 12 to 35% and the best linear regression models were fitted for the basic density, having V 0 and E d as independent variables. For the mechanical properties, the values of R 2 varied from 18 to 63% and higher correlations were found between parallel-to-grain compression strength and E d , and rigidity, static bending and Ed. Ultrasound presented the potential to estimate the properties of tropical wood species from the ASF.

Predicting mechanical properties of clear wood from Acacia mangium provenances using ultrasound

“…The correlation coefficients ranged between 0.44 and 0.87 for individual provenances (Table 4). Considering the relationship between Ed and MOR in this study, the results were similar to those from tropical wood species (Baar et al 2015;Mascarenhas et al 2021). Using ultrasound, de Oliveira et al (2002) reported coefficients of determination between Ed and MOR for Goupia glabra and Hymenaea sp.…”

“…Duong et al (2019) also reported a strong positive correlation existed between Vu and CS (r = 0.70) of Melia azedarach. In contrast, Mascarenhas et al (2021) showed that there was a significant (P < 0.001) but weak correlation (r 2 = 0.29) between ultrasonic propagation speed and bending strength of tropical wood species. In addition, Duong and Ridley-Ellis (2021) reported a poor relationship between stress wave velocity and MOE (r 2 = 0.23) and no significant relationship between stress wave velocity and MOR for Melia azedarach.…”

Biological Control of Termites: A Bibliometric and State-of-the-Art Review

“…plantations, which are among the most widely cultivated wood species in the world, is reported (GOVORUSHKO, 2019;PRASTYANINGSI et al, 2020;EVANS, 2021). These aspects are fundamental for the timber market in tropical regions, especially in Brazil, which stands out worldwide in the area of native and planted forests with robust tropical timber production (MASCARENHAS et al, 2021;MEDEIROS et al, 2021).…”