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Properties of four domestic hardwood speciesCarmona Uzcategui, Marly Gabriela 01 May 2020 (has links)
This study aimed to evaluate the physical and mechanical properties of red oak (Quercus spp.), white oak (Quercus spp.), hard maple (Acer saccharum) and yellow-poplar (Liriodendron tulipifera) and compare them to values from past publications. Mechanical testing was conducted on small, clear, defectree specimens from red oak, white oak, hard maple and yellow-poplar following the standard ASTM D143. Percentage of latewood, moisture content, specific gravity, modulus of elasticity (MOE), modulus of rupture (MOR), compression parallel and perpendicular to the grain and Janka hardness were determined. Results indicated that mechanical properties for red oak, white oak, hard maple and yellow poplar have not changed substantially because the average values remain in a range that is very close to the ones published in past studies. Thus, values from the Wood Handbook can still be used for engineering purposes.
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Stand Level Compatible Diameter Distribution Models for Red Oak-sweetgum Complexes on Minor Stream Bottoms in the SouthHoward, Wesley James 30 April 2011 (has links)
Southern bottomland hardwood forests lack effective growth and yield predictive models primarily due to the complexity of the ecosystems. These models are important tools for relative comparison of management schemes and making sound management decisions to obtain optimal future yields. Starting in 1982, 150 red oak-sweetgum bottomland hardwood growth and yield plots were established in northern and central parts of Mississippi. These plots were remeasured in 1988, 1992, 1993, 2005, 2006, and 2007 along with the addition of new plots. A diameter distribution model was developed from stand level component equations constructed in a previous study (Iles 2008; Schultz et al. 2010). The equations created performed well when testing the predicted survival and diameter growth against the observed data. The resulting growth and yield system will be a basis for better decision making in the comparison of management alternatives as well as increased conservation and efficient utilization of wood products.
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The margin for yield improvement for no. 1 common 5/4 red oak in a conventional rough millYun, Linda Y. January 1989 (has links)
This study examined the potential for improvement within a conventional (crosscut-first) rough mill. Improvement was measured in terms of volume and also value of cuttings produced.
Current levels of yield were obtained from an in-plant yield study of 138 boards. The same material was then processed with a computer optimization program designed to simulate a crosscut-first operation. Tests between the two methods, actual and optimized, showed that . current levels of cutting volume production were not able to be improved upon with optimization. Due to the varying costs of different length cuttings, however, a significant increase in the value of cuttings produced was possible. The distribution of cutting lengths produced was found to be a significant factor in these results. / Master of Science / incomplete_metadata
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Optimization of edging and trimming operations for red oak lumberRegalado, Carmen de Castro 24 October 2009 (has links)
This research project investigated the upgrading of edging and trimming operations for red oak lumber through computer-aided optimization. The main objective was to evaluate how lumber value recovered by actual hardwood operations compare with the maximum value obtainable through the optimization of edging and trimming.
An optimization procedure was developed involving the use of an iterative computer program for finding optimum edging and trimming solutions. The hardwood lumber grading program developed by Klinkhachorn et.al. [1988] was incorporated into the procedure. Comparison of results with actual values indicated that only 63% to 80%, approximately, of the maximum theoretical value was obtained in the sawmills studied.
Edging and trimming optimizing systems equipped with scanners that provide only wane information have been successfully applied in softwood lumber manufacturing. The second part of this study investigated the lumber value recovery that can be expected if a similar system were applied to hardwood edging and trimming, i.e., if optimization were based only on wane input. Based on the output of a computer optimization program that maximizes volume yield subject to wane limitations, it was found that for red oak boards, an average value of approximately 80% of the optimum can be recovered through the application of this procedure. / Master of Science
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Mass transfer, creep and stress development during the drying of red oakRice, Robert W. January 1988 (has links)
The purpose of this research was to measure and simulate the major perpendicular to gain strain components and associated stresses which develop as the result of mass transfer and restraint of shrinkage in red oak. Particular emphasis was placed on the rheological or creep components of strain.
Mass transfer was measured during the first four days of drying under increasingly severe conditions. The resulting moisture gradient profiles were parabolic in shape under nearly all drying conditions. The pattern developed quickly and was modeled with reasonable accuracy using Fick's second law.
Three major strain components occur in drying. These are termed elastic strain, visco-elastic creep and "set" or mechano-sorptive creep. The magnitude and variation of each of these components was measured during the first four days of drying under increasingly severe conditions.
Using a slicing technique to cut very thin wafers of wood parallel to the surface, the elastic strain was shown to be quite small. The experiments led to the conclusion that the maximum stress develops within a few cell thicknesses of the surface.
Much of the experimental work centered on the t of the rheological or creep components of strain, The magnitude of the visco-elastic creep was found to be about the same order of magnitude as the elastic strain and was clearly a function of the applied stress. The major strain component during drying was shown to be mechano-sorptive creep. This type of creep occurs in a number of polymeric materials undergoing diluent movement or temperature change. The maximum magnitude of the mechano-sorptive component was about 30 times larger than the maximum elastic strain. Mechno-sorptive creep was shown to be directly related to moisture loss and, to a lesser extent, a function of applied load.
Using relationships derived from the experimental data, a computerized simulation was developed to predict the development of stress and the probability of checking early in drying. The simulation makes use of data on elastic strain, mechano-sorptive creep and the elastic modulus. The concept worked well in this study, but its application is limited by the lack of strain data for the surface layers representing the outer few cell thicknesses where stress is greatest early in drying.
As an adjunct, acoustic response tests were performed on green samples stressed perpendicular to grain in flexure under third point loading conditions. The evidence indicates that the onset of surface failure can be predicted prior to the appearance of macroscopic checking. The acoustic response pattern is typical of that which occurs in brittle glassy polymers such as polystyrene. / Ph. D.
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Soil Moisture Profiles and Root growth of Hardwood Trees Planted in Different Groundcovers on the Steep Slopes of Reclaimed Mine SitesAubuchon, Elizabeth Anne 01 December 2010 (has links)
Surface mining is a major industry in eastern Tennessee that removes much of the native forest. To restore the forest, reclamation practices are used. These include planting a ground cover species with native hardwoods. Competition between the ground cover and tree species for soil resources could hinder growth and decrease survival of the trees. Northern red oak (Quercus rubra) was used for this study to examine the possible effects of this competition and the relationships between root growth and soil moisture through a field and a greenhouse experiment.
A field experiment was designed using four different ground cover treatments (Soldiago nemoralis, Medicago sativa, Panicum virgatum, and bare ground) with four different hardwood species. Northern red oak was measured for this study. The results showed that the site physical factors (slope position, soil temperature, and soil moisture) were not related to each other. Soil moisture varied by depth with the lower depths (46 cm to 76 cm) was much higher than the upper depths (0 to 46 cm). Root growth did not differ by treatment or percent cover. Both soil temperature and ground cover percentage increased over the growing season. Root growth showed a relationship with depth with the upper depths of soil having more roots than the lower depths. Annual rye was used as well as switchgrass, alfalfa, and bare ground treatments for a green house study. Two-year-old Northern red oak seedlings were first planted in pots and then ground covers were established and grown for 9 weeks. Then water stress was imposed over two dry down periods during which transpiration and soil moisture were measured. Root growth was measured after harvest. The results showed a relationship between transpiration and soil moisture. Soil moisture was highest in the bare ground treatment and lowest in the annual rye treatment. Fine root development of trees was greatest in the bare and alfalfa and lowest in the annual rye. Switchgrass had the second highest soil moisture and third highest fine root development. Root growth was related to both soil moisture and transpiration.
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Effect of Alliaria petiolata invasion on ectomycorrhizal colonization of Quercus rubraCastellano, Steven Michael. January 2008 (has links)
Thesis (M.S.)--Miami University, Dept. of Botany, 2008. / Title from first page of PDF document. Includes bibliographical references (p. 22-29).
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A stand level growth and yield model for red oak/sweetgum forests in Southern bottomlandsIles, John Clinton, January 2008 (has links)
Thesis (M.S.)--Mississippi State University. Department of Forestry. / Title from title screen. Includes bibliographical references.
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Determination of flexural strength of structural red and white oak and hardwood composite lumberSherrington, Alan 13 May 2022 (has links) (PDF)
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.
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A Stand Level Growth and Yield Model for Red Oak/Sweetgum Forests in Southern BottomlandsIles, John Clinton 09 August 2008 (has links)
A greater emphasis is being placed on hardwood management, yet there has been relatively little effort to develop growth and yield information for hardwood forest types. Measurements on permanent growth and yield plots collected in 1981, 1988, 1994, and 2006 in minor stream bottoms in Mississippi and Alabama were used to construct a stand level growth and yield model for red oak/sweetgum stands. The model predicts arithmetic mean diameter, quadratic mean diameter, trees per acre, basal area, total tree height, and cubic foot volume per acre for the total stand and by species. Different sets of equations were constructed depending on the amount of information known about a hardwood stand. Models were chosen based on significance of variables, coefficient of determination, index of fit, and biological trends. Predicted stand development patterns are discussed. These models will be base models for a complete diameter distribution growth and yield model.
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