Treesearch

In this study, CLT trailer decking was manufactured to current military trailer decking specifications, verified using PRG320 performance criteria, and treated with either waterborne or oil borne wood preservatives. Preliminary results show adequate uptake of preservative solution and subsequent testing shows minimal effect due to treatment. Field durability tests are also being conducted of treated and untreated materials in tropical sites in Suriname and 8-month data is presented herein. Presence of gaps in the CLT layup have proven problematic as it presents a pocket for collection of...

The main purpose of this study is to quantify and compare the embodied carbon (EC) from the materials used or designed to build the Adohi Hall, a residence building located on the University of Arkansas campus in Fayetteville, AR. It has been constructed as a mass timber structure. It is compared to the same building design with a steel frame for this study. Based on the defined goal and scope of the project, all materials used in the building structure are compared for their global warming potential (GWP) impact by applying a life cycle assessment (LCA) using a cradle-to-construction site...

Evaluation of physical and mechanical heterogeneity in commercial paperboards is needed to promote their use in structural applications, especially within the field of packaging. Understanding the range of their behaviors is needed to compete with other materials in the current marketplace and expand in others. This work describes the physical and stiffness heterogeneities of twelve commercial materials using tensile tests in the cross-machine direction and several inverse analyses. The effects of grammage, thickness, and apparent density on tensile stiffness were evaluated in both the...

Wood (or timber) mats are portable and temporary modular platform assemblies that spread short duration heavy loads from construction equipment out across large areas, protecting the environment from rutting and erosion. They are used throughout the United States and around the world. These assemblies facilitate access to construction sites and provide stable working surfaces during infrastructure and construction projects. Some examples of these types of projects include dragline operations, pipe- and transmission-line building and rebuilding, wind and cellular tower construction, crane...

Structural insulated panels (SIPs) are an important construction material that has been developed through many years of research at the USDA Forest Service, Forest Products Laboratory. There are concerns, however, related to the in-service performance of this important construction material. More data are needed to determine creep performance of these panels to help the industry address these concerns. This report describes a test method that was developed to measure the creep performance of SIPs. Topics covered in this report include a summary of the development of sandwich-type structural...

The ability of some white rot basidiomycetes to remove lignin selectively from wood indicates that low molecular weight oxidants have a role in ligninolysis. These oxidants are likely free radicals generated by fungal peroxidases from compounds in the biodegrading wood. Past work supports a role for manganese peroxidases (MnPs) in the production of ligninolytic oxidants from fungal membrane lipids. However, the fatty acid alkylperoxyl radicals initially formed during this process are not reactive enough to attack the major structures in lignin. Here, we evaluate the hypothesis that the...

The widely used high-density polyethylene (HDPE) polymer has inadequate mechanical and thermal properties for structural applications. To overcome this challenge, nano zinc oxide (ZnO) and nano boron oxide (B2O3) doped lignin-containing cellulose nanocrystals (L-CNC) were blended in the polymer matrix. The working hypothesis is that lignin will prevent CNC aggregation, and metal oxides will reduce the flammability of polymers by modifying their degradation pathways. This research prepared and incorporated safe, effective, and eco-friendly hybrid systems of nano ZnO/L-CNC and nano B2O3/L-CNC...

Cellulose nanocrystals (CNCs) are bioderived one-dimensional species with versatile surface chemistry and unique self-assembling behavior in aqueous solutions. This work presents a scientific approach to leverage these characteristics for creating CNC network templates and processing them to engineer a novel silicon (Si)-based material called silicon nano-quill (SiNQ) for energy storage applications. The SiNQ structure possesses a porous, tubular morphology with a substantial ability to store lithium ions while maintaining its structural integrity. The presence of Si suboxides in the SiNQ...

Volatile products from thermal decomposition of lignocellulosic biomass have been well characterized, but the solid- and liquid-phase reactions during the early stages of decomposition are largely unknown. Here the initial solid-phase biomass thermal deconstruction reactions were analyzed in situ and with high particle heating rates, delineating how these processes occur. A variety of instrumentation was used to quantify the extent and relative rates of deconstruction, demonstrating that biopolymers resist the thermally energetic conditions to differing degrees, even when ensconced in...

Understanding and controlling the diffusion of ions and chemicals within the secondary plant cell walls are pivotal in various applications of biomasses. Recent studies have shown that inorganic ion diffusion through secondary cell walls is controlled by a moisture-induced glass transition in amorphous polysaccharides, including amorphous cellulose and hemicelluloses. Understanding the diffusion of ions in these structures has been the subject of numerous recent experiments; however, a deep understanding of the underlying mechanisms of interactions between ion atoms and water/hemicellulose...