Abstract
Portuguese forests have changed in recent years. These changes were mainly boosted by the wildfires that affected a significant percentage of the softwood area. Data from 2015, conveyed by the Portuguese Institute for Nature Conservation and Forests, indicates that hardwoods occupy 70% of the Portuguese forest area. This paper presents the Blackwood (Acacia melanoxylon R. Br.) species potential, focusing on construction applications, based on recent studies performed at the University of Coimbra and SerQ—Forest Innovation and Competences Center. The valuation of Blackwood for structural applications has been considered through the non-destructive and destructive assessment of their mechanical properties as sawn wood. Their potential was also assessed for a more technologically engineered wood product, the glulam. The dynamic modulus of elasticity (MOE) was estimated through the Longitudinal Vibration Method (LVM) and the Transformed Section Method (TSM); the static MOE and bending strength were assessed through a four-point bending test. Agreement was obtained between both approaches. Sawn Portuguese Blackwood showed a density of 647 kg/m3, 13,900 MPa of MOE and a bending strength of 65 MPa (mean values). The glulam beams fabricated with this raw material had improved properties relative to sawn wood, most obviously concerning the bending strength, with an improvement of 29%. This proves the significant ability and potential of these species to be used in construction products with structural purposes like sawn wood and glulam.
Highlights
Portuguese forests and the wood products obtained from them represent a significant contribution to the Portuguese economy, being responsible for 3% of Gross Domestic Product in 2015 [1]
The Transformed Section Method (TSM) considers a cross-section with homogeneous properties, instead of the actual heterogeneous one, which allows for the application of conventional beam theory elastic formulas
The prediction of static modulus of elasticity (MOE) was considered by the use of the Transformed Section Method boards the considers
Summary
Portuguese forests and the wood products obtained from them represent a significant contribution to the Portuguese economy, being responsible for 3% of Gross Domestic Product in 2015 [1]. Portuguese law prohibits the felling of species like Cork Oak and Holm Oak, unless duly and previously authorized, which means that, in most the cases, only branches from thinning are available, resulting in a material with dimensions unsuitable for construction applications. This implies a decrease in the available area of hardwood forests for these applications by approximately 37%. A study focusing on the density and growth of Blackwood in different sites of the raw material to increase the wood quality. A study focusing on the density and growth of in Portugal in showed a mean width of 6 mm in.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
