As paradas planejadas gerais nas indústrias papeleiras, normalmente realizadas anualmente, são fundamentais devido ao processo produtivo e estratégicas para a competitividade no setor. Face à sofisticação dos equipamentos e instalações, denotando intervenções complexas e de grande porte, altos custos e riscos potenciais de acidentes e danos ambientais, procura-se uma caracterização desses eventos como grandes empreendimentos. Esses, fazem parte da estratégia de manutenção definida para a planta fabril, sendo gerenciados pela equipe de manutenção que atua voltada a disponibilidade, confiabilidade, qualidade e produtividade. Neste sentido, este trabalho desenvolve uma sistemática de manutenção para o gerenciamento e controle das paradas planejadas gerais em processos de produção de celulose e papel, com a finalidade de facilitar e promover o sucesso na execução de todas as atividades e etapas envolvidas. Para isso, contextualiza-se o setor e as paradas planejadas; são revisados os principais conceitos, técnicas, práticas e ferramentas características à gestão da manutenção, qualidade e conhecimento; são estudadas abordagens específicas voltadas aos processos de produção contínua; é verificada uma prática empresarial do setor e; finalmente, é proposta uma sistemática fundamentada nestas pesquisas. Como principais benefícios observam-se: a sinergia entre as equipes de manutenção e operação; a valorização da manutenção na gestão do processo produtivo; a competitividade do negócio; a otimização dos recursos e as alavancagens de produtividade. / The general planned stops within the paper industries, once in the year as a rule, are due to the productive process and competitiveness strategies in that business sector. Current sofistified equipments and facilities call for complex and significant interventions. Because high costs involved and potential risks of both accidents and environmental nature damage, those events are characterized as important projects. They are part of the strategy defined for the manufacturing plant, thus being managed by the maintenance team focusing availability, reliability, quality and productivity. In view of such scenario, this paper develops a maintenance system addressing the management and control of planned stops within the cellulose pulp and paper production processes. The scope is to facilitate and promote the success when carrying out all the activities involved. Therefore, the context of the sector and planned stops is discussed; the main concepts, techniques, practices and tools specific to the management of maintenance, quality and knowledge are reviewed; approaches specific to the continuous production processes are studied; business practices within the sector are analyzed, and, finally, a systemic approach proposal is made grounded on the preceding research. The most important benefits observed were: the achievement of synergy among the maintenance and production teams; the true understanding of the maintenance value in the productive process; the business competitiveness; resources optimization as well as productivity boosting.

Plant cell walls compose the largest source of sugars on earth and are a potential source after conversion for liquid transportation fuels. However, the crystalline region of cellulose and the lignin that incases it present significant obstacles for enzymes to digest. This lowers the sugar yield, which ultimately decreases the production efficiency of bioethanol. A pretreatment that could help lowering the amount of crystallinity; meanwhile, breakdown the matrix of lignin and polysaccharides that cover cellulose fibers would be ideal. Here we propose a physical pretreatment strategy of electron beam irradiation that could potentially decrease cellulose crystallinity as well as unzip the lignin structure. Four types of biomass: cellulose, yellow pine, yellow poplar, and switchgrass were irradiated with a 12 MeV electron beam (Sterigenics, Inc.) at dosages of 0, 54, 80, 148 and 403 kGy. By combining the result from the wet chemical analysis of percent weight glucose/ cellulose from the HPLC, percent crystallinity from the Wide Angle X-Ray Diffraction (WAX) and the change of chemical functionality from Fourier Transform Infrared Spectrometer (FTIR), a promising effect is obtained in pine and yellow poplar but not in cellulose and switchgrass. A significant increase in percent glucose is observed for pine at higher doses as shown by (r = 0.97, P< 0.0076) which are 9.4 and 27% at 0 and 403 kGy. The amount of glucose considerably changes from all different types of biomass over time (P< 0.0001). A strong correlation of decreasing in percent crystallinity was found in poplar (r = -0.89, P< 0.05) from 32.4% to 17.4% and related to an average increase in percent glucose produced from 30 to 55% comparing between 0 and 403 kGy.

This research assessed the influence of hydrologic gradients on woody debris dynamics in a Cumberland Plateau watershed, eastern Kentucky, U.S.A. Although the breakdown of wood can be attributed to several different processes, including leaching, biological decay, fragmentation, and transport, the influence of differing flow regimes has been unstudied. The objectives of this study were to examine how stream channel type (temporary vs. perennial) affected wood processing dynamics (i.e., mass loss and macroinvertebrate colonization and standing stock patterns). Two questions were addressed: (1) do mass loss rates of wood differ across hydrological gradients in stream channels?, and (2) do macroinvertebrate colonization and standing stock patterns vary in relation to hydrologic gradients? Although within each channel type both dry mass and ash free dry mass loss followed a negative exponential model (p < 0.05), there wasn’t a significant between-channel difference in mass loss rates (p > 0.05). Breakdown rates (-k) ranged from 0.133 – 0.194year-1 for perennial streams compared to 0.103 – 0.170year-1 in the temporary streams. Collector-gathers comprised the greatest proportion of macroinvertebrates, accounting for 65.5% (temporary) and 59.3% (perennial) of all taxa colonizing wood bundles, followed by shredders (16.1%, 16.8%), predators (16.8%, 20.1%), (scrapers < 0.1% in both reaches) and filtering collectors (1.2%, 3.7%). Overall, there were no significant between-channel differences for total macroinvertebrate abundance, total macroinvertebrate biomass, and similarly for abundance and biomass of all functional groups. There was a trend, however, of decreasing density and biomass over time of collector-gathers and shredders on wood. Overall, hydrological gradients had no effects on short-term breakdown rates of woody debris or macroinvertebrate colonization patterns. Studies of wood breakdown have been shown to require long study periods (≥ 5 years), therefore, future studies of hydrological gradient may show differing results for woody debris breakdown.

Plant cell walls compose the largest source of sugars on earth and are a potential source after conversion for liquid transportation fuels. However, the crystalline region of cellulose and the lignin that incases it present significant obstacles for enzymes to digest. This lowers the sugar yield, which ultimately decreases the production efficiency of bioethanol. A pretreatment that could help lowering the amount of crystallinity; meanwhile, breakdown the matrix of lignin and polysaccharides that cover cellulose fibers would be ideal. Here we propose a physical pretreatment strategy of electron beam irradiation that could potentially decrease cellulose crystallinity as well as unzip the lignin structure. Four types of biomass: cellulose, yellow pine, yellow poplar, and switchgrass were irradiated with a 12 MeV electron beam (Sterigenics, Inc.) at dosages of 0, 54, 80, 148 and 403 kGy. By combining the result from the wet chemical analysis of percent weight glucose/ cellulose from the HPLC, percent crystallinity from the Wide Angle X-Ray Diffraction (WAX) and the change of chemical functionality from Fourier Transform Infrared Spectrometer (FTIR), a promising effect is obtained in pine and yellow poplar but not in cellulose and switchgrass. A significant increase in percent glucose is observed for pine at higher doses as shown by (r = 0.97, P< 0.0076) which are 9.4 and 27% at 0 and 403 kGy. The amount of glucose considerably changes from all different types of biomass over time (P< 0.0001). A strong correlation of decreasing in percent crystallinity was found in poplar (r = -0.89, P< 0.05) from 32.4% to 17.4% and related to an average increase in percent glucose produced from 30 to 55% comparing between 0 and 403 kGy.

As paradas planejadas gerais nas indústrias papeleiras, normalmente realizadas anualmente, são fundamentais devido ao processo produtivo e estratégicas para a competitividade no setor. Face à sofisticação dos equipamentos e instalações, denotando intervenções complexas e de grande porte, altos custos e riscos potenciais de acidentes e danos ambientais, procura-se uma caracterização desses eventos como grandes empreendimentos. Esses, fazem parte da estratégia de manutenção definida para a planta fabril, sendo gerenciados pela equipe de manutenção que atua voltada a disponibilidade, confiabilidade, qualidade e produtividade. Neste sentido, este trabalho desenvolve uma sistemática de manutenção para o gerenciamento e controle das paradas planejadas gerais em processos de produção de celulose e papel, com a finalidade de facilitar e promover o sucesso na execução de todas as atividades e etapas envolvidas. Para isso, contextualiza-se o setor e as paradas planejadas; são revisados os principais conceitos, técnicas, práticas e ferramentas características à gestão da manutenção, qualidade e conhecimento; são estudadas abordagens específicas voltadas aos processos de produção contínua; é verificada uma prática empresarial do setor e; finalmente, é proposta uma sistemática fundamentada nestas pesquisas. Como principais benefícios observam-se: a sinergia entre as equipes de manutenção e operação; a valorização da manutenção na gestão do processo produtivo; a competitividade do negócio; a otimização dos recursos e as alavancagens de produtividade. / The general planned stops within the paper industries, once in the year as a rule, are due to the productive process and competitiveness strategies in that business sector. Current sofistified equipments and facilities call for complex and significant interventions. Because high costs involved and potential risks of both accidents and environmental nature damage, those events are characterized as important projects. They are part of the strategy defined for the manufacturing plant, thus being managed by the maintenance team focusing availability, reliability, quality and productivity. In view of such scenario, this paper develops a maintenance system addressing the management and control of planned stops within the cellulose pulp and paper production processes. The scope is to facilitate and promote the success when carrying out all the activities involved. Therefore, the context of the sector and planned stops is discussed; the main concepts, techniques, practices and tools specific to the management of maintenance, quality and knowledge are reviewed; approaches specific to the continuous production processes are studied; business practices within the sector are analyzed, and, finally, a systemic approach proposal is made grounded on the preceding research. The most important benefits observed were: the achievement of synergy among the maintenance and production teams; the true understanding of the maintenance value in the productive process; the business competitiveness; resources optimization as well as productivity boosting.

Reclaimed wood is material salvaged from old, abandoned buildings that offers sustainable living to communities. There have been previous studies on reclaimed wood, but a limited amount linking reclaimed wood to consumerism. In August 2021, an online survey was conducted to gauge consumers’ knowledge of the industry and attitudes on reclaimed wood practices. Consumers are U.S. citizens 18 years of age or older. Study results indicate that respondents have little knowledge regarding reclaimed wood. Of the 1,516 respondents, 44% seem knowledgeable of reclaimed wood. Most respondents are not aware that reclaimed wood is a separate industry. Respondents believe there should be better marketing practices. Respondents also believe reclaimed wood to be environmentally friendly, durable, and aesthetically pleasing. The reasons respondents would purchase reclaimed wood are sustainability, aesthetics, and to exercise a need. Respondents acknowledge the importance of the origin of wood products. Respondents also acknowledge the importance of the industry.

As the use of engineered wood products as such as cross-laminated timber (CLT) evolves in United States, it’s imperative to understand its behavior under different circumstances as well as to explore new possible streams for product’s application. In that matter, it was proposed that a research study would be developed to evaluate the performance of CLT panels focusing on strength and stiffness properties. To accomplish this goal, three main objectives were traced: 1) To complete preliminary test on traditional lumber in order to observe notched wood failure behavior focusing on strength, ductility, and failure mode; 2) To perform mechanical testing and non-destructive evaluation on 3-ply CLT control panels in order to compare design calculation methods and efficiency of NDE on CLT; and 3) To perform mechanical testing on notched 3-ply CLT samples to evaluate the influence of notches and stitching reinforcement on panels. Based on these objectives, this dissertation features five main sections: 1) General Introduction, 2) Technical note: Ductility and brittleness in small clear notched S-P-F beams, 3) Evaluation of the modulus of elasticity and modulus of rupture of cross-laminated timber with longitudinal vibration NDE techniques, 4) Case study of 3-ply commercial southern pine CLT mechanical properties and design values, and 5) Effect of notching on 3-ply southern pine cross-laminated timber panels stiffness and strength.

This document will outline the findings of three separate and independent studies: Study 1: In or around 1972, an experimental building was constructed. One of the intents of the construction project was to demonstrate advancements in wood building construction design. It was value-engineered throughout. That is, its materials and systems were intended to function at or near design capacity. In 2019, part of the roof of the structure collapsed. This case study investigates two potential factors that led to the failure: stress concentration in excess of the 12 allowable stress for 2 × 4 web members and insufficient plywood sheathing to support live loads 13 caused by large rain events. Study 2: As a building material, cross laminated timber (CLT) has exponentially grown in popularity recently. Although performing superior to numerous other popular building materials, a consistent issue presented in wood construction is the effect of moisture on performance. This study looks to investigate the effect of moisture content on the performance of a 2-way dowel type fastener system loaded in shear perpendicular to the major strength axis. It was found that the peak load capacity of the specimens was not affected by the moisture content of the CLT. However, yield strength increased as the moisture content decreased. Lastly it was found that the failure mode changed from ductile to brittle as specimens became drier than 12% moisture content by mass. Study 3: Inherently, the weak point of any structure is the connection system. This phenomenon is particularly apparent in wooden structures as dowel type fasteners place tremendous amounts of stress perpendicular to the grain of the wood, as well as shear stress under the bolt. In hopes of mitigating this behavior, fiberglass reinforcement of these samples is examined to see if both failure mode as well as overall performance of these fasteners could be improved with reinforcement. It was found that fiberglass significantly reduced the standard deviation of failure strength of fasteners, significantly increased the overall strength of the fasteners, increased the efficiency of the fasteners, and finally increased the probability of bearing failure opposed to block shear failure.

In this research, flexural properties of mill-run, in-grade white oak and red oak lumber from a single mill and commercially available laminated hardwood composite were evaluated. Structurally graded green (wet) freshly sawn red oak and white oak 5 by 10-cm (2 by 4-in.) nominal lumber as well as glue-laminated hardwood composite billets were tested in bending and their modulus of rupture (MOR) and modulus of elasticity (MOE) properties were developed. It is well documented that MOR and MOE are two major indicators to evaluate flexural strength of wood lumbers. From these data, summary statistics, design values, and mean separations were calculated and reported. Overall, the red and white oak lumber performed similarly to structural No. 2 grade material. The hardwood composite billets were highly uniform. Each of the three materials demonstrated a reasonably good relationship between MOE and MOR, thereby suggesting that MOE could be used as a selection criterion for strength in a commercial use situation.

Over the past few decades, university level US Forestry and Wood Science and Technology programs have faced declining enrollment. As a result, the seeming disinterest of younger generations has impacted employment in these sectors. In an attempt to bridge the communication gap among colleges/industries, this study was created to attract the interest and maintain the enthusiasm of new generations of professionals and currently enrolled college students in the United States. In September 2021, an online survey was created and distributed to over 1500 alumni and students and received 1,495 usable surveys. Analysis performed on the resultant data included descriptive statistics and chi-square calculations. Although the study results indicate that the current generation of students and professionals appear to have basic knowledge surrounding the forestry and wood products/science industries, they showed a lack of awareness of the available careers linked to the sector.