Creosote, a coal tar distillate product, has been used to preserve wooden utility poles for well over 100 years. Such use began in the late 1800s and continues to this day. Creosote’s efficacy in protecting wood from decay, termite attach, and general weathering has been demonstrated by actual performance of poles in utility service and in documented field and laboratory testing. The American Wood Protection Association has standardized and long recognized the efficacy of creosote preservation. With production of pentachlorophenol ending after 2022, preservation may easily convert to creosote preservative. Creosote preservative also is an environmentally sound choice in that used poles can be used as fuel and otherwise, creosote degrades biologically. Wood is sustainable as new trees are grown to replace poles while the poles are sequestered carbon. Utility service life of creosote preserved wooden poles typically lasts for 70 to over 100 years with inspection and maintenance. Utilities can expect new creosote preserved poles to last into the next century.Abstract
Estimating industrial carbon dioxide emissions at the national scale is crucial for China's carbon peak and carbon neutralization targets, as well as the low-carbon development of the Chinese furniture manufacturing industry. For this purpose, in this study the Intergovernmental Panel on Climate Change Tier-2 methodology was used to evaluate the carbon dioxide emissions of the Chinese furniture manufacturing industry at the national scale. The results show that carbon dioxide emissions increased from 219.50 × 10,000 tons of CO2 equivalent in 2000 to 850.68 × 10,000 tons of CO2 equivalent in 2019. Moreover, carbon dioxide emission intensity decreased from 9.50 tons of CO2 per million dollars to 1.73 tons of CO2 per million dollars in this period. Moreover, electricity and raw coal were observed to have a significant influence on carbon dioxide emissions, followed by diesel oil, gasoline, heat energy, and natural gas. The results reveal that the Chinese furniture manufacturing industry has generally realized low-carbon development over the past two decades. This work proposes several suggestions to reduce carbon dioxide emissions from the Chinese furniture manufacturing industry, including promoting the use of clean electricity, the installation of photovoltaic cells, industrial transformation and upgrading, the optimization of transport modes for product delivery and material supply, and the employment of low-carbon raw materials.Abstract
The goal of this research was to test the effect of low-moisture-content veneer on the strength and durability of plywood test specimens constructed with a soy-flour adhesive. Soy-flour adhesive systems offer certain environmental and health advantages but research studies and performance data are lacking currently for a variety of wood types and end uses. Soyad adhesive was used in this study due to its natural, renewable soy flour, a novel cross-linking resin, and lack of added formaldehyde. Test specimens were prepared using heartwood of hickory and red oak and sapwood of hickory. These wood types were used to represent some of the most challenging wood adhesion conditions. Analytical tests included determination of select chemical properties of the adhesive and wood veneer, measurement of strength properties of the adhesive bond, and assessment of delamination tendencies of bonded panels following water soaking.Abstract
Cross-laminated timber (CLT) is an increasingly popular wood-based alternative for large building applications. CLT panels are typically not treated due in part to a perceived lack of efficient and effective methods for treating large panels and a lack of information on what effect treatment processes may have on the panels' mechanical properties. We propose that treating CLT panels with borate solution, applied under vacuum in flexible bags, could provide a practical and effective option for providing preservative protection for interior applications. Samples were cut from commercially produced CLT panels and treated with borate solution using vacuum. The samples were then evaluated for preservative retention, swelling, and degradation of mechanical properties. Initial treatments resulted in a wide range of preservative retentions and property effects among the products tested. In subsequent adjustments, the treatment parameters were changed to provide consistent and sufficient retention among the products. The vacuum treatment method effectively penetrated cracks in the lumber and the bond lines (adhesive joint between adjacent lamellae). Swelling and effects on mechanical properties were minimal in the adjusted samples. In addition to these samples that were treated in a rigid pressure vessel, a larger sample was successfully treated in a flexible plastic bag. Data from this study support the concept that vacuum treatment of CLT panels with borate can provide sufficient levels of preservative retention, can be adjusted to the material being treated, and has minimal effects on mechanical properties.Abstract
Wood has thousands of uses and the industry plays an important role in the US economy. There are many sectors within the industry such as the lumber, engineered wood products, pulp and paper products, and reclaimed lumber sectors. However, most consumers are unaware of the importance and the diversity of the industry. Reclaimed lumber is one particular sector that can have a great economic and environmental impact among communities. In 2021, an online survey was conducted to assess consumer knowledge of the reclaimed lumber sector and perceptions and attitudes toward the sector and reclaimed lumber products. Of the 1,516 respondents, 59 percent indicated being somewhat knowledgeable of the wood products industry but only 44 percent felt they were knowledgeable of reclaimed lumber. Caucasian and male respondents were more likely to indicate they were knowledgeable. Although respondents had somewhat negative responses toward the environmentally friendliness of the industry, their responses toward the environmental and economic benefits of reclaimed lumber products were positive. The information obtained from this study will be beneficial to companies that are interested in creating strategies to market new or innovative products to reach new or existing customers.Abstract
The Internet is a powerful tool that can be leveraged to explore user search behavior. Google Trends is a compelling database that tracks the frequency with which all users search any given word. There is thus an opportunity to see if the search histories obtained from Google Trends can be merged with data analytics to tease out underlying relationships with similar searches for cross-laminated timber (CLT). In this study, multiple linear regression was used to predict the search strength of the term cross laminated timber from 60 possible variables that may be directly or indirectly associated with CLT. This study was able to model the search term CLT (R2 = 0.76) using a reduced model of 20 variables. However, while prediction strength was strong, our primary interest was to statistically classify and rank important variables that might be important to CLT. To achieve this, the Mallow's Cp statistic was used to build the most robust model possible. To confirm with the literature, we also compared our study with another Web-based study and found a significant linear relationship between the t statistic in our study and the frequency of the same or similar search term in their study (R2 = 0.76). This agreement between studies helps to support our hypothesis that multiple linear regression coupled with Google Trends is a new tool that may assist marketers to identify emerging trends important to CLT.Abstract
Sawing variation (SV), the degree of deviation from a specified target lumber size, is an unavoidable component of the sawing process. SV is influenced by several factors such as machine, material, set works, feed works, and cutting parameters. To account for these factors resulting in deviations from the desired target size, the target thickness of the lumber cut must be increased such that only a minimal number of boards is less than target thickness. Thus, the greater the amount of SV, the larger the target thickness must be such that a minimal quantity of undersized lumber is produced. Hence, with larger amounts of SV come greater waste and decreased opportunities for optimizing lumber recovery. However, the decrease in material loss due to a reduction in SV may not necessarily translate into a statistically significant increase in lumber product recovery by volume. This study explored the effect of varying degrees of SV on lumber recovery by volume for a range of hardwood log diameters using the US Forest Service's LOg ReCovery Analysis Tool sawmill simulation software. A minimal average recovery improvement of 3 percent due to reduced SV was observed across all kerf thicknesses, equating to a production value improvement of $336,000 for an 8 million board feet mill. Results indicate that the recovery gains realized by volume depend upon the log diameters sawn, the lumber target thickness, and the change (reduction) in SV.Abstract
Sawing variation (SV) describes all variations that exist in the production of lumber due to machine, material, set works, feed works, and cutting parameters. The necessary oversizing of board thickness due to SV diminishes sawmill profits and hence efforts must be made to reduce the variation. However, such efforts are costly and sawmill personnel generally do not know at which point efforts to reduce (SV) become more costly than oversizing the boards. In an accompanying paper we examined the impact of SV on lumber volume recovery and found that volume recovery increased comparatively more for thinner than for thicker kerfs and that the effect of reduced SV became more pronounced as diameter increased. In this second manuscript, the effect of SV on the quantity of boards sawn for a range of hardwood log diameters using the US Forest Service's LOg ReCovery Analysis Tool sawmill simulation software was researched and compared with the volume improvement from an earlier paper. Results showed that significant differences in the number of boards obtained was dependent on the log diameters sawn, the lumber target thickness, and the change (reduction) in SV. A minimal average recovery improvement of 3 percent due to reduced SV was observed across all kerf thicknesses, equating to a potential production value improvement of $336,000 for an 8 million board feet mill. All sawmills can benefit from reducing SV, but mills that saw large-diameter logs might consider pursuing SV reduction more aggressively than a sawmill sawing mostly small-diameter logs.Abstract
Assessing 2 by 6 Southern Pine Lumber Flexural and Tensile Properties with Nondestructive Techniques
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 in tension parallel to the grain to determine tension MOE (Et) and ultimate tensile stress (UTS). The overall mean for Et was 11,339 MPa and the UTS mean was 28.54 MPa. Correlations between growth characteristics, and physical and mechanical properties were analyzed. From the linear regression analysis, a strong relationship between Et and dynamic MOE was found using both NDT tools. Multivariable regression models were developed to improve UTS estimation. NDT techniques are recommended for the estimation of mechanical properties of No. 2 grade 2 by 6 southern pine lumber.Abstract