Treesearch

Timber genus identification based on the anatomical features of wood is well established in botany. However, species-level wood identification is not always possible based on traditional wood morphology techniques alone. To compensate for the deficiencies of traditional methods, direct analysis in real time coupled to Fourier transform ion cyclotron resonance mass spectrometry (DART-FTICR-MS) was used to obtain the mass spectral fingerprints of different timber species. Using heartwood samples of two morphologically similar species, Pterocarpus santalinus and Pterocarpus tinctorius,...

Roundwood is increasingly sourced from highly productive plantations that yield excellent growth. Information is needed on the wood properties from plantations because these trees will contain a higher proportion of low stiffness corewood compared to naturally regenerated trees of the same size. The objective of this study was to examine the within-tree variation in stiffness for Douglas-fir and loblolly pine grown in the United States through assessment of specific gravity (SG) and ultrasonic velocity (USV). Approximately 500 pith-to-bark radial strips collected from multiple height...

Fused borate rods were installed at equal distances along the length of unseasoned red or white oak bridge timbers. Moisture content and boron levels were examined at 15 and 30 weeks after rod installation at various points along the bridge timbers. Moisture contents for both red and white oak were greater than 60% at all time checks. Boron levels were highest near the point of borate rod placement, but high levels were also recorded 4 and 6 inches from the rod installation point. Boron levels transverse to the boron rod installation point were lower than in the longitudinal direction....

The objective of this study was to determine the feasibility of using a transverse free vibration testing method to nondestructively evaluate the bending stiffness and strength of full-size (1220 x 2440 mm) wood composite panels (WCPs). Based on the principle of transverse free vibration of a thin plate, the dynamic modulus of elasticity (MOE) of a full-size WCP supported on two nodal-lines was derived using the Rayleigh method. Transverse free vibration test was conducted on 54 full-size medium density fiberboard (MDF) panels and 36 full-size particleboard (PB) panels under a two-nodal-lin...

The objective of this study was to explore the potential of an acoustic impact test as a nondestructive evaluation procedure to assess the soundness of hardwood logs in terms of internal decay, void, and defect ratio. Fifteen logs of four hardwood species (black cherry, white oak, red oak, and cottonwood) were obtained and subjected to acoustic impact testing. The logs were subsequently dissected for visual examination and physical mapping of the internal defects. The acoustic response signals were analyzed to derive acoustic velocity (through FFT), time centroid (through moment analysis),...

This Research Note describes the rationale for and design of a XyloScope, a digital imaging system for viewing and recording macroscopic images of wood for a XyloTron machine-vision wood identification system, and provides a bill of materials and the associated technical drawings of its components.

The use of cross-laminated timber (CLT) as a building material is gaining popularity in the North American building sector, especially in mid- to high-rise building designs. This study presents the methodology of life-cycle cost analysis (LCCA) and an example of a hypothetical case study in Portland, Oregon, USA, of a CLT mass timber building compared with a baseline code-compliant concrete alternative. It was found, not unexpectedly, that the mass timber building with premium energy and water saving designs exhibited a lower total life-cycle cost (TLCC) than a concrete building for a...

Global demand for construction materials has grown greatly in the last century, contributing to unsustainable growth and detrimental impacts on the ecosystem. To aid in sustainable growth and reduce our environmental footprint, renewable construction materials, such as lumber, have been incorporated into green building activities. To quantify the environmental footprints of construction products, a method called life-cycle assessment is used. This study determined the environmental attributes associated with manufacturing redwood lumber in northern California using the unit process...

Buckling Restrained Brace Frames (BRBF) are a proven and reliable method to provide an efficient lateral force resisting system for new and existing structures in earthquake prone regions. The fuse-type elements in this system facilitate stable energy dissipation at large load deformation levels. Currently, the new trend towards mass timber vertical structures creates a need for a lightweight compatible lateral force resisting system. A Buckling Restrained Brace (BRB) component is possible to construct and feasible to implement when combining a steel core with a mass timber casing herein...

Fungi that decay wood have characteristic associations with certain tree species, but the mechanistic bases for these associations are poorly understood. We studied substrate-specific gene expression and RNA editing in six species of wood-decaying fungi from the ‘Antrodia clade’ (Polyporales, Agaricomycetes) on three different wood substrates (pine, spruce, and aspen) in submerged cultures. We identified dozens to hundreds of substrate-biased genes (i.e., genes that are significantly upregulated in one substrate relative to the other two substrates) in each species, and these biased genes...