Treesearch

Sustainable timber use is vital to the health of American forests, and building materials represent a significant market for wood materials. However, due to the combustible nature of wood, wood building products are at risk of both becoming target fuel and contributing to the fuel load/fire spread. To reduce the risks, fire protection measures, such as fire-retardant treatments, can be employed. Here, a summary of current research related to the fire protection of wood building products is provided from exterior uses in the wildland-urban interface to interior applications for tall wood...

Lignin is a waste product in the paper industry and lignocellulosic biorefineries, in addition to being the second most abundant renewable biopolymer on Earth. Valorization of useless lignin into high value-added advanced materials not only helps address the environmentally detrimental biowaste but also satisfies the societal need for energy. While lignin has been converted into porous carbon, made into slurry, and pasted onto metal forms as an electrode for lithium-ion batteries and supercapacitors, there remains issues with how to scale up the process while achieving great area and mass...

Water vapor sorption is a fundamental characteristic of wood as a building material. Apart from empirical prediction, models are often used to interpret the time-dependent process of water vapor uptake (sorption kinetics) and equilibrium states of water in wood (sorption isotherms). This paper summarizes our recent investigations into measurement methods and popular models that are widely used for interpreting these physical phenomena. Commonly used criteria for determining equilibrium moisture content with the dynamic vapor sorption technique yield much larger errors than previously...

Though ballistic projectile penetration of wood has been studied for centuries, standard models overestimate the thickness of wood required to stop projectiles, often by a large margin. Adhesive lamination via contemporary manufacturing methods can produce mass timber panels of unprecedented thickness, yet industry standard layups of softwood cross-laminated timber (CLT) cannot stop projectiles traveling at velocities specified by current protective design requirements. To develop mass timber panels that comprehensively mitigate blast, ballistic, and forced entry threats, seven reinforced...

A mass timber lateral force resisting system (LFRS) is proposed using a timber buckling restrained brace (TBRB) for improved seismic performance in high seismic applications. To develop a high-performance braced frame, it is essential to quantify the behaviour of the connections including failure modes and moment-rotation capacities. Cyclic and monotonic tests were conducted on six mass timber beam-column connections to investigate the response of mass timber joints connected with slotted-in steel plates and mild steel dowels. The goal of the subassembly tests was to measure the maximum...

Quasistatic nanoindentation is a proven tool that provides information on the micromechanical behavior of wood cell walls. However, quasistatic tests cannot probe the time-dependent mechanical behavior shown by wood. Nanoindentation dynamic mechanical analysis (nanoDMA) can measure the viscoelastic properties of wood cell walls. This research aimed to study the quasistatic and viscoelastic properties of individual radiata pine wood (Pinus radiata D. Don) cell wall layers. To minimize variability and retrieve both properties at the same locations, a load function composed of a multiload-quas...

Horizontal wood diaphragm systems, whether decked with conventional or mass timber panels, transfer wind and seismic loads to vertical elements of a lateral force-resisting system (LFRS), in flexible, rigid, or semirigid fashion. Characterizing and calculating the resulting diaphragm deflections determines the distribution of forces to critically loaded components and a significant portion of lateral building translations and rotations. Deflection equations for sheathed wood structural panel (WSP) diaphragms are well established in US design standards in a four-term expression that models...

The objective of this study was to assess the flexural and tensile properties of 702 pieces of No. 2 grade 2 by 6 southern pine lumber using nondestructive testing (NDT) techniques. Longitudinal and transverse vibration techniques were used to test each specimen. The mean dynamic modulus of elasticity in the longitudinal direction was 11,246 MPa, and the mean transverse vibration dynamic modulus of elasticity was 11,491 MPa. Proof-loading bending tests were conducted on each specimen. The mean bending modulus of elasticity (MOE) was 10,615 MPa. Each specimen was then destructively tested...

Deposition of small adhesive particles, called microstickies, onto pulp processing equipment and paper machines causes quality and operational problems for recycling mills. The factors that control deposition of microstickies onto surfaces of metal parts remain unclear. In this work, aluminum surfaces with a range of surface roughness were exposed to slurries containing microstickies. The deposition results showed that flat surfaces promote the aggregation and deposition of microstickies particles. Uneven surfaces tended to favor deposition of smaller microstickies, 0.2–1 μm, which may be...

This study proposes an efficient biorefining strategy for co-producing of bioethanol, furfural, and lignin nanoparticles (LNPs) from birch wood based on acid hydrotropic fractionation. Birch was fractionated into glucan-rich washed water-insoluble solids (WIS) fraction and xylose-rich spent liquor (SL) fraction with a low p-toluenesulfonic acid (p-TsOH) concentration of 15% (w/v). The obtained WIS was utilized to produce 75.5 g/L ethanol (76.3% ethanol yield based on initial sugars in the enzymatic hydrolysate) through separate hydrolysis and fermentation. Meanwhile, the xylose-rich SL was...