Treesearch

Woodworkers know that wood is porous in that adhesive flows into lumens for a mechanical interlock (1) and that wood absorbs water, allowing the use of water-borne adhesives. However, the anatomical aspects of wood that lend to its porosity are much more complicated and have a greater influence on adhesive performance than is normallyrealized or discussed. This porosity can have both positive and negative effects on adhesive performance. A greater appreciation of how porosity relates to adhesive performance is important in designing new and improved adhesive formulations.

The effect of timber length on time-of-flight acoustic longitudinal measurements was investigated on the structural timber of four Spanish species: radiata pine (Pinus radiata D. Don), Scots pine (Pinus sylvestris L.), laricio pine (Pinus nigra Arn.), and maritime pine (Pinus pinaster Ait.). Time-of-flight longitudinal measurements were conducted on 120 specimens of dimensions 90 x 140 mm using three commercially available acoustic instruments (Sylvatest Duo, USLab, and Microsecond Timer). Time-of-flight data were initially obtained from the full-length (4 m) specimens, and then from the...

Quantification of the mechanical properties of cellulose nanomaterials is key to the development of new cellulose nanomaterial based products. Using contact resonance atomic force microscopy we measured and mapped the transverse elastic modulus of three types of cellulosic nanoparticles: tunicate cellulose nanocrystals, wood cellulose nanocrystals, and wood cellulose nanofibrils. These modulus values were calculated with different contact mechanics models exploring the effects of cellulose geometry and thickness on the interpretation of the data. While intra-particle variations in modulus...

Provides current and historical data on primary and secondary hardwood products, production, prices, international trade, and employment.

Biochar application to forest soils can provide direct and indirect benefits, including carbon sequestration. Biochar, the result of thermochemical conversion of biomass, can have positive environmental climate benefits and can be more stable when field-applied to forest soils than wood itself. Categorizing greenhouse gas (GHG) emissions and carbon sequestration profile are critical to the long-term sustainability of this practice. Using life-cycle assessment as a sustainable metric tool, this study evaluated the fuel consumed to pelletize, transport, and field-apply biochar produced from...

There has been a resurgence of interest and research on using bio-based materials as wood adhesives; however, they have achieved only limited market acceptance. To better understand this low level of replacement, it is important to understand why adhesives work or fail in moisture durability tests. A holistic model for wood adhesives has been developed that clarifies many issues of wood bond durability. This model addresses performance challenges that bio-based adhesives must overcome to compete with synthetic adhesives. Additionally, bio-based adhesives face challenges on economic and...

More wood use in the United States to construct low-rise nonresidential (NR) buildings would increase consumption and production of softwood (SW) lumber, engineered wood products, and structural and nonstructural wood panels. Using a consequential life-cycle analysis, we estimated the change in net CO2 emissions thatwould be caused by increased use of SWlumber and structural panels in NR construction. Carbon (C) storage and emissions were projected over 50 years for baseline and increased wood use scenarios using the US Forest ProductsModule operating within the Global Forest Products...

This report summarizes the proceedings, including key points and identified research needs, that evolved from the Mass Timber Research Workshop, which was held at the USDA Forest Products Laboratory (FPL), November 3–4, 2015. The purpose of the workshop was to bring design professionals, researchers, and industry leaders together to examine the state-of-the-art in mass timber construction, with an emphasis on cross-laminated timber, and to identify technical barriers to the broader use of wood in engineered structures that need to be addressed. Following a plenary session on mass timber in...