Treesearch

This paper highlights research results from a joint effort between the Forest Products Laboratory (FPL) in the United States of America (USA) and the University of Coimbra (UC) in Portugal (PT). The main objective is the development of a Timber-Concrete Composite system (TCC) that utilizes precast concrete deck panels that accelerate construction times and can easily be removed to facilitate bridge repair/rehabilitation efforts and reuse options. The research is focused on various critical aspects such as the type of interconnection between the concrete deck and the glued laminated timber...

This paper presents a framework to better identify and measure defects in a bridge using drone-based inspection images integrated with grayscale image enhancement techniques. For this study, a DJI Matrice 210 drone was used for the inspection of a three-span timber bridge with concrete decking located in Keystone, South Dakota. During the inspection, the drone recorded a series of videos of the bridge using the MOVie (MOV, video file extension) video format. MOV-based image analysis was conducted to identify a variety of defect types (i.e., efflorescence, water leakage, spalling, and...

The Equivalent Lateral Force (ELF) procedure is the most widely used seismic analysis approach, because of its simplicity and practicality in preliminary and final design phases. This paper applies the ELF procedure to a hypothetical building that stands 5 stories tall, with a 4-story superstructure supported on a rocking story of elliptically profiled cross-laminated timber (CLT) walls. First-generation prototypes made from six CLT panels of 5-ply, 175 mm, thickness—each measuring 2.44 m by 3.66 m in respective width and height—demonstrated that elliptical geometry controls lateral...

During the summer of 2019, seven stress-laminated deck timber bridges were evaluated to assess their field performance and serviceability. These bridges were originally constructed during a six year period (1988-1994) using hardwood lumber as part of a national program initiative in the USA. Its aim was to increase the use of wood in transportation structures primarily in the rural regions of the country. To assess bridge performance, comprehensive visual inspections were conducted and advanced inspection tools were utilized to accurately assess the bridge superstructure components using a...

Effcient wood production and utilization requires knowing the wood quality attributes of forest resources relevant to various end uses, prescribing appropriate silvicultural treatments that positively influence wood quality, and then, at the time of harvesting, sorting and allocating standing timbers to the most appropriate markets [1–3]. The field of forestry has many widely accepted field tools, sampling procedures, and models for gathering and summarizing data and making projections of growth, yield, and tree size; however, counterparts for wood quality assessment have lagged behind...

Each year, the U.S. Department of Agriculture’s (USDA’s) Forest Service Forest Products Laboratory, Durability and Wood Protection research work unit (FS RWU 4723) installs and/or observes plots of soil treated with candidate termiticide products. These products may or may not be available to pest management professionals (PMPs) for application, depending on federal and state registration. This article reports on the latest results of these studies, and provides data for those products that have reached federal registration. Data provided are limited to label-approved rates of application...

Wheat straw was rapidly fractionated using maleic acid (MA) as an acid hydrotrope at atmospheric pressure under a range of conditions. MA hydrotropic fractionation (MAHF) was very selective in dissolving lignin and hemicelluloses resulting in a cellulose-rich water insoluble solids (WIS), which was evaluated for producing fibers through bleaching and cellulosic nanofibrils by fibrillation, as well as glucose through enzymatic saccharification. The residual lignin (RL) within the WIS has a low degree of condensation, which eased bleaching. The RL was also carboxylated through MAHF, which...

While it is known that modifying the hydroxyls in wood can improve the decay resistance; what is often missing in the literature is whether these modifications alter wood nanostructure, and how these changes correlate to the improved decay resistance. Here, we used SANS to probe the effects of alkylene oxide modification on wood nanostructure. Southern pine wood samples were chemically modified to various weight percentage gains (WPG) using four different alkylene oxides: propylene oxide (PO), butylene oxide (BO), epichlorohydrin (EpH) and epoxybutene (EpB). After modification, the samples...

Wood pallets play a critical role in the movement and storage of goods worldwide. They are an important component in the complex global supply chain and used by almost every industry. It is therefore important to assess the environmental implications of the wood pallet supply chain and identify optimization strategies that can be implemented. In this paper, primary 2018 annual production data collected from U.S. pallet manufacturers were used to develop the first industry-average life-cycle inventory (LCI). A new functional unit was proposed to perform a more refined and accurate environmen...

This study assessed the environmental impacts and economic feasibility of generating heat using wood-briquettes (WBs), and heat and electricity using torrefied-wood-briquettes (TWBs). WBs and TWBs were manufactured from forest residues using portable systems and delivered to either residential consumers or power plants in the United States. An integrated cradle-to-grave life-cycle assessment (LCA) and techno-economic analysis (TEA) approach was used to quantify environmental impacts and minimum-selling prices (MSPs) of heat and electricity, respectively. Results illustrated that 82% and...