Estimation of compression and shrinkage properties of Brazilian tropical timber through porosimetry analysis by mercury intrusion

Abstract

Wood is a natural material with properties that are strongly influenced by anatomical characteristics, so studies that aim to correlate properties through empirical equations in search of simplification to obtain the values of their characteristics are essential. In this context, this work aims to generate multiple regression models to estimate the properties of shrinkage and compression parallel and normal to the grain of Brazilian tropical woods as a function of the values of porosity, density, and for both properties, with porosity being obtained by mercury intrusion porosimetry. As a result, the radial (RRT) and total tangential (RTT) shrinkage could be estimated through porosity. However, it was not possible to estimate them considering only density as an independent variable. All the models that were used were able to accurately estimate the modulus of resistance and modulus of elasticity values (fc,0, Ec,0, fc,90, and Ec,90).

Indicadores de flexibilidad de madera laminada, densificada y reforzada con fibra de carbono

“…Caso excepcional es la madera densificada laminada donde se observa una disminución del módulo de elasticidad en la dirección tangencial con respecto a la dirección radial. Este incremento en el módulo de elasticidad de la madera se puede explicar admitiendo dos paradigmas vigentes en ciencias de la madera: por una parte, que su resistencia mecánica aumenta a medida que la densidad se incrementa (Prihatmaji et al, 2012;Almeida et al, 2022) y, por otra parte, que el módulo de elasticidad en flexión tangencial es mayor que el radial (Kim et al, 2022;Mascia et al, 2022). En el caso de la madera sólida, las diferentes capas de crecimiento se alinean paralelamente, lo que permite modelar la madera como un material multicapas a la escala anatómica de los tejidos de crecimiento anuales de un árbol.…”

Estimation of Flexural Tensile Strength as a Function of Shear of Timber Structures

“…Lahr et al [8] analyzed the relationship between characteristic values of shear and compressive strength, both evaluated in the direction parallel to the fibers, concluding that the coefficient value 0.24 (f v0,k = 0.24 × f c0,k ) is more accurate than the value of 0.12 established by the Brazilian standard [6]. Other researches have also been undertaken with the same purpose using the same or other methodology [9][10][11][12][13][14].…”