Tropical wood species: alternative model to determine the characteristic compressive strength perpendicular to grain

Brazil has a vast area of native forests with the potential to be sustainably exploited for application in civil construction. Density is a key factor when analysing the characteristics of different wood species and their future uses, and additionally it can be used as an estimator for other mechanical properties of wood. Furthermore, in a developing country like Brazil, carrying out various characterisation tests for different wood species is sometimes impossible because of the associated high costs. The Brazilian standard ABNT NBR 7190:1997, Design of Timber Structure, governs wood construction and timber structures in Brazil. However, this guideline lacks equations that link the majority of mechanical characteristics to density. Therefore, the main aim of this study was to propose regression models for estimating compressive strength perpendicular to grain, for 17 native species of Brazilian tropical wood, as a function of apparent density and the characteristic value of apparent density. From the results obtained, it is possible to conclude that all the regression models provided in this study were successful in estimating characteristic compressive strength perpendicular to grain (fc90,k), and that the model from Equation 3 in this work, a linear model with one independent variable, might be included in future revisions of ABNT NBR 7190:1997.