Dissertations / Theses: 'Shale Mechanical properties Testing'

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Audette, Scott. "Mechanical Properties of Aerospace Composite Parts Made from Stitched Multilayer 3D Carbon Fibre Preforms." Thesis, Université d'Ottawa / University of Ottawa, 2014. http://hdl.handle.net/10393/31691.

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Producing composite parts using low-cost processes such as resin transfer moulding (RTM) has received much interest in the aerospace industry. RTM manufactured components require near net shape preforms which closely fit mould cavities. To reduce labour costs associated with composite production, automated preforming processes must be utilized. However, obtaining reproducible high quality preforms is required for manufacturing consistent high quality parts. Stitched multilayer 3D non crimp fabric preforms are well suited for automation and an investigation into quality and performance of components manufactured from these preforms is required. This thesis provides an initial evaluation of quality and mechanical properties of components made from stitched multilayer 3D non crimp fabric preforms using RTM. Similar sized flat plates of varying fibre volume fractions were manufactured to evaluate flexural modulus and strength, short beam shear strength and drop weight impact resistance of the material. Also, integral reinforced panels (IRPs) featuring a reinforcing section joined to a flat plate of varying laminating sequences were manufactured to evaluate debonding strength between sections. Optical microscopy was performed on component samples to determine quality based on void content and was found to be within acceptable limits for production composites. Flexural moduli were found to be comparable with theoretical expected values, however flexural strength was limited by the presence of transverse stitches. Short beam shear strength results showed high consistency between specimens, however were lower than comparable values found in literature. Impact specimens showed consistency among specimens, with greater damage resistance than comparable values found in literature. Determining debonding strength proved difficult as different failure modes were observed between IRPs, however, initial baseline values were acquired.

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Hatami, Mohammad. "Multiscale Analysis of Mechanical and Transport Properties in Shale Gas Reservoirs." Ohio University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1614950615095796.

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Bobko, Christopher Philip 1981. "Assessing the mechanical microstructure of shale by nanoindentation : the link between mineral composition and mechanical properties." Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/47731.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2008.
Includes bibliographical references (leaves 335-351).
Shale is a multi-phase, multi-scale sedimentary rock that makes up 75% of the earth's sedimentary basins and is especially critical in petroleum engineering applications. At macroscopic scales, shales possess a diverse set of possible compositions, resulting in a diverse set of mechanical properties. This thesis assesses microstructure and material invariant properties of shale as the link between engineering performance and composition. A comprehensive experimental microporomechanics approach, employing advanced experimental and analytical nanoindentation techniques, provides the basis for assessment of microstructure and material invariant properties. Nanoindentation experiments and analysis tools are designed to probe and infer the elastic and strength properties of the porous clay composite in shale. The results of this investigation show that properties of the porous clay composite scale with the clay packing density in the material, but otherwise do not depend on mineral composition. These scaling relationships are representative of a granular composite of spherical particles, and lead to identification of intrinsically anisotropic material invariant elastic properties and intrinsically isotropic material invariant hardness properties. The material invariant hardness represents a combination of cohesive and frictional behavior that is seen to scale with the average clay packing density in the sample. Nanoindentation results also provide evidence of packing density distributions that are analogous to pore size distributions.
(cont.) These observations are combined to define a model of the elementary building block of shale. Exploring the physical origin of this building block suggests that it represents an agglomerated polycrystal group of individual clay minerals. Particles in the porous clay composite exhibit fractal packings, which suggest a quantitative link between contemporary theories about the origin of friction and the experimental scaling of friction in shale. The new understanding provided by this thesis represents a leap forward for predictive models of shale behavior. The model of the elementary building block can be used as a basis for micromechanical homogenization models which predict poroelastic properties and strength behavior of shale at the lab-bench scale based on only two volume fraction parameters. The success of these models validates the elementary building block model and illustrates its engineering significance.
by Christoper P. Bobko.
Ph.D.

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Allen, Katherine Ruth. "Methods of testing the mechanical properties of orthodontic wires /." Title page, table of contents and summary only, 1994. http://web4.library.adelaide.edu.au/theses/09DM/09dma427.pdf.

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Li, Hui. "Effects of Water Content, Mineralogy, and Anisotropy on the Mechanical Properties of Shale Gas Rocks." Thesis, University of Louisiana at Lafayette, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10235426.

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In shale gas development, the mechanical properties of shale are crucial in hydraulic fracture propagation, wellbore stability, and the productivity of a shale gas wells. In this dissertation, acoustic velocity tests, uniaxial compressive tests, and Brazilian tensile tests were conducted on Eagle Ford and Mancos shale to investigate gas shale mechanical properties, including dynamic mechanial properties and static mechanical properties (compressive and tensile mechanical properties). Water content, mineralogy, and anisotropic effects on shale mechanical properties were analyzed.

Ultrasonic velocity measurements were performed on Eagle Ford shale samples. Dynaimic elastic properties were determined according to the compressive- and shear-wave vleocities. The results showed that both P- and S-wave velocities increase as confining pressure increases. Horizontal elastic modulus, vertical elastic modulus, and shear modulus increase with increasing confining pressure. While horizontal and vertical Poisson’s ratio exhibited more or less invariant with confining pressure. Transverse isotropy is an appropriate model to characterize Eagle Ford gas shale. Elastic properties of Eagle Ford shale are direction-dependent. Horizontal Young’s modulus is higher than vertical Young’s modulus and horizontal Poisson’s ratio is higher than vertical Poisson’s ratio. Increasing water content reduce Young’s modulus and shear modulus significantly. Induced water can make the shale softer. Water increase Eagle Ford shale’s anisotropies. Both P- and S- wave velocities decrease with increasing of TOC and clay content. Dynamic Young’s modulus, shear modulus, and bulk modulus vary inversely with TOC and clay. Poisson’s ratio does not correlate with TOC or clay content for these test samples.

Static mechanical properties were investigated by conducting uniaxial compressive tests and Brazilian tensile tests on Eagle Ford and Mancos shale samples. A new method was developed to analyze tensile elastic behavior of materials. The imbibed water significantly reduces the uniaxial compressive strength. Young’s modulus of wet samples is lower for corresponding dry samples. The maximum Young’s modulus decrease is up to about 70%. The imbibed water makes the shale softer. Poisson’s ratio increase with water content. Bedding plane/laminations have a significant impact on Eagle Ford indirect tensile strength, but not on Mancos shale. The imbibed water significantly reduces tensile strength and tensile Young’s modulus, but increase tensile Poisson’s ratio. Low clay content in the Eagle Ford shale (around 6%) and high clay content in the Mancos (around 22%) might be the explanation for the overall lower tensile strength of the Mancos than Eagle Ford shale.

Static and dynamic elastic properties of Eagle Ford shale samples are compared. Static Young’s modululs is lower than dynamic Young’s modulus. There is no strong correlations between static and dynamic Poisson’s ratio observed for the tested samples. The relationship of compressive and tensile mechanical properties of Eagle Ford shale are investigated. Tensile Young’s modululs is 0.76 to 0.98 times lower than corresponding compressive Young’s modulus. There is either no strong correlations between tensile and compressive Poisson’s ratio observed for the tested samples.

Water weaken mechanism was analyzed. Three potentially major weakening mechanisms—chemical effects, water clay interaction, and capillary pressure increase—were discussed in detail.

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Kalaugher, Elizabeth Mary. "The mechanical properties of CVD diamond coated fibres." Thesis, University of Bristol, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.264062.

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Zulu, Andrew Wisdom. "Thick Composite Properties and Testing Methods." Thesis, KTH, Lättkonstruktioner, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-243885.

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In most application to date reinforced carbon fiber composites have been used in relatively smaller thickness, less than 10mm thick and essentially for carrying in-plane loads. As a result, design and testing procedures were developed which reflected the need to understand the in-plane response of the material. recently, engineers and designers have begun to use reinforced carbon fiber composites in thicker sections, where an understanding of the through-thickness response is of para-mount importance in designing reliable structures, particularly where the through-thickness strength has a controlling influence on the overall structural strength of the component. In this thesis tests will be done on carbon fiber non-crimp fabric (NCF) which will be loaded in compression and shear and elastic moduli and strength will be evaluated. In characterizing the through-thickness mechanical properties of a composite, the objective is to produce a state of stress in the test specimen which is uniform and will repeatedly measure the true properties with accuracy. In this study, specimens were machined from two blocks of thick (~20 mm) laminates of glass/epoxy and NCF carbon fiber infused with vinylester and tested in compression, and shear.

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Frei, Katherine Rebecca. "Morphology Tuning and Mechanical Properties of Nanoporous Gold." Thesis, Virginia Tech, 2018. http://hdl.handle.net/10919/91899.

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Nanoporous gold is an exciting topic that has been highly researched due to its potential in applications including sensing, catalysts, gas storage, and heat exchangers, made possible by its high surface area to volume ratio and high porosity. However, these applications tend to require a specific morphology, which is often difficult to control. In this work, significant strides have been made in tuning the morphology of nanoporous gold by studying the effect of different fabrication parameters on the ligament diameter, pore diameter, and ligament length, three characteristics which are most discussed in previous studies concerning nanoporous gold. This material also, generally shows a brittle behavior despite it consisting of a normally ductile constituent element, limiting many commercial applications. There have been multiple simulated studies on the tensile mechanical properties and the fracture mode of this material, but limited experimental tensile testing research exists due to technical difficulty of conducting such experiments with small fragile samples. We examine the tensile mechanical behavior of nanoporous gold with ligament sizes ranging from 10 to 30 nm using in situ tensile testing under an environmental scanning electron microscope (ESEM). A specially designed tensile stage and sample holders are used to deform the sample inside the ESEM, allowing us to observing both the macro and microscopic structure changes. Our experimental results advance our understandings of how porous structure influence the mechanical properties of nanoporous gold, and they also serve to increase the accuracy of future simulation studies that will take this material a step towards commercial use by providing a thorough understanding of its structural mechanical limitations.
MS

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Al-Hajri, Hamood Said Ali. "Investigation of the controls of fluid flow through shale and their relation to its mechanical properties." Thesis, University of Leeds, 2018. http://etheses.whiterose.ac.uk/21976/.

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Understanding mechanisms of fluid flow through shale is very important as these sedimentary rock act as caprock, key source of unconventional hydrocarbon, seal for geological CO2 storage and radioactive waste disposal sites. Four mechanisms of fluid flow were identified; matrix flow by single or multiphase flow, flow through faults and fractures and flow through preferential pathways induced by high pressure fluid. Knowledge gaps associated with understanding the controls of these mechanisms were identified in this thesis. A series of experimental and simulation work was conducted to fill these knowledge gaps. Shale samples were collected from different location with a wide range of petrophysical, mechanical and mineralogical properties. Multiphase flow and sealing capacity assessment requires knowledge of threshold pressure of shale, which is challenging using standard methods due to the stress sensitive of shale. Using Mercury Porosimetry Under Confining Stress (MPUCS) instrument, it was proven experimentally that shale would act as effective seal and would not leak by multiphase flow through the undeformed matrix under in situ conditions. The radioactive waste management industry argues that leakage mainly occurs via flow along pathways formed by high gas pressures (pathway dilation). However, there is no micro mechanical model to describe formation and propagation of these pathways. Pathway dilation in clay-rich sediments was investigated by injecting melted Field’s metal into synthetic shale sample. Results suggest that compaction plays a key role in formation and propagation of these pathways. It is quite important to understand failure mechanics of shale in order to be able to argue the existence of conductive faults and fracture and their capability to re-seal. Anticipation of formation and closure of faults and fractures require knowledge of mechanical properties such as the apparent preconsolidation pressure, which is difficult to obtain for shale. A new simple technique was developed to measure the preconsolidation pressure under hydrostatic condition using MIP instrument. Micro-indentation was proposed to measure elastic properties as it is difficult to obtain core plugs that are sufficient long for tri-axial testing. Faults and fracture are often argued to be conduits to fluid flow across shale. However, these features could close and re-seal but knowledge of controls for fracture closure is still elusive. Controls of fracture closure in shale were investigated by conducting a series of flow experiments through artificial fracture using a set of different shale samples. It was shown that porosity, clay content and stress state controls fracture closure. It was suggested that fractures in soft shale with high porosity and clay content samples have potential to close and reseal under in situ condition whereas stiff shale will have their fracture open under same conditions. Finite element analysis (FEA) was performed to simulate the same fracture closure experiment, which also provided results that agree with the suggestions made from experimental work.

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Saka, Kolawole. "Dynamic mechanical properties of fibre reinforced plastics." Thesis, University of Oxford, 1987. http://ora.ox.ac.uk/objects/uuid:0514854d-36db-4cc1-b377-03a75550ab76.

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A small gas gun, capable of accelerating a projectile 1m long by 25.4mm diameter to about 50 m/s, and an extended split Hopklnson bar apparatus have been designed and constructed for the tensile impact testing of fibre reinforced composite specimens at strain rates of the order of 1000/s. Elastic strain measurements derived from the Hopkinson bar analysis are checked, using strain gauges attached directly to the specimen and the validity of the elastic moduli determined under tensile impact is confirmed. Epoxy specimens reinforced with plain-weave fabrics of either carbon or glass or with several hybrid combinations of the two in various lay-ups, giving five different weight fractions of reinforcement from all-carbon to all-glass, have been tested in tension at three strain rates, nominally, ~10^-3/s, ~10/s and ~10³/s. The effect of both hybrid composition (volume fraction of carbon reinforced plies) and applied strain rate on the tensile modulus, the tensile strength and the strain to fracture is determined and a limited hybrid effect is observed in specimens with a carbon volume fraction in the approximate range 0.6 to 0.7 where, at all three strain rates there is an enhancement of the failure strain over that for the all-carbon plies and an increased failure strength, most marked in the impact tests, over that predicted by the rule of mixtures. The fracture surfaces of specimens are examined by optical and scanning electron microscopy and the failure process in the hybrid composites is related to that found in the all-carbon and the all-glass specimens. The classical laminated plate theory and the Tsai-Wu strength criterion are used to predict the stiffness and strength of the hybrid composites from the elastic and strength properties of the constituent plies. Analytical predictions are in good agreement with experimental measurements.

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Krus, David Jr. "Finite element analysis of thin film mechanical properties." Case Western Reserve University School of Graduate Studies / OhioLINK, 1992. http://rave.ohiolink.edu/etdc/view?acc_num=case1059745475.

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Merle, Benoit [Verfasser]. "Mechanical Properties of Thin Films Studied by Bulge Testing / Benoit Merle." Erlangen : FAU University Press, 2013. http://d-nb.info/1065004818/34.

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Eshetu, Tefera Zegeye. "Impact Acoustic Testing for Classification of CGI Mechanical and Material properties." Thesis, KTH, Industriell produktion, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-140320.

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Automotive industries have been putting extensive effort into producing engine materials considering resistance and weight of the engine material. This material should withstand higher combustion pressure and in the meantime should be lighter. Compacted Graphite Iron (CGI) is a material that could allow achieving these design requirements. But the variation of the CGI material and mechanical properties are very high within the given specifications. The thesis is focused on classifying CGI according to its material and mechanical properties. Impact Acoustic Testing method is a Non Destructive Testing method which is fast and might be able to classify the CGI materials based on its properties. The method can measure the structural response of a part. Its volumetric approach tests the whole part providing objective and quantitative results. The result was that the method could able to distinguish between gray iron and CGI, and could distinguish partly among CGI. Keywords: Non Destructive Testing, Impact Acoustic Testing, Compacted Graphite Iron

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Valero, Diana (Diana E. ). "Compression testing and measurement of material properties of a double network hydrogel." Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/98758.

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Thesis: S.B., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2015.
Cataloged from PDF version of thesis.
Includes bibliographical references (page 26).
Double network hydrogel samples were synthesized and manufactured out of polyacrylamide (PAAm) and alginate solutions. They were casted into cube molds with each side measuring 20 mm. Samples were tested under compressive loads in cyclic compression tests and stress relaxation tests. A viscoelastic model was applied and material properties were calculated using the experimental data. The elastic modulus of these PAAm-alginate gels was found to be 35kPa, while the viscosity, [eta], was found to be 1.43 kPa-s. The viscous response was found to have a dependency on the strain rate by an exponential factor of 0.26. Using the applied theoretical model and the experimentally determined material properties, you can then characterize the mechanical response of the PAAm-alginate hydrogel when it undergoes small strains.
by Diana Valero.
S.B.

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Sabry, Mohammad Sabry Ismail. "The influence of specimen size on the measurement of mechanical properties of fabrics." Thesis, University of Leeds, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.329211.

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Carney, Alison Fox. "The effect of microstructure on the mechanical properties of a 30% titanium diboride/70% alumina composite." Thesis, Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/19994.

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Khasawneh, Qais Azzam. "On the Analysis of Mechanical Properties of Nanofiber Materials." University of Akron / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=akron1226939318.

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Malpally, Deepthi Rao. "Uncertainty Analysis of Mechanical Properties from Miniature Tensile Testing of High Strength Steels." DigitalCommons@USU, 2014. https://digitalcommons.usu.edu/etd/4029.

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This Miniature mechanical testing study is concerned with the use of miniature specimens to identify the mechanical properties of stainless steel Type 304, sensitized Type 304 and SA516 Grade 70 carbon steel as a viable replacement for the standard sized mechanical testing. The study aims at obtaining suitable specimen geometry and tensile testing proce- dure for miniature mechanical testing whose mechanical properties are comparable to that of conventional specimens of ASTM A370-10 of the same steel. All specimens are at and the gauge length cross section will be varied to obtain suitable geometry. The miniature tensile testing results are further validated by using Monte Carlo Method (MCM) for uncertainty estimation in order to know the probability distribution of mechanical properties. Miniature specimens with a cross section of 3 mm2 and 12 mm gauge length are found to produce equiva- lent mechanical properties as tested from standard-sized specimens. If a reasonable agreement is received, it will provide us with a very useful tool to evaluate mechanical properties of de- graded materials, which cannot be removed from service for standard testing, for repair and service life evaluation.

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How, Yew Seng. "Modeling of impression testing to obtain mechanical properties of lead-free solders microelectronic interconnects." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2005. http://library.nps.navy.mil/uhtbin/hyperion/05Dec%5FHow.pdf.

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Thesis (M.S. in Engineering Science (Mechanical Engineering))--Naval Postgraduate School, December 2005.
Thesis Advisor(s): Indranath Dutta. Includes bibliographical references (p. 79-80). Also available online.

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Li, Xuan. "Hydrogen Effects on X80 Steel Mechanical Properties Measured by Tensile and Impact Testing." Scholar Commons, 2016. http://scholarcommons.usf.edu/etd/6110.

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The effect of hydrogen charging current density and tensile strain rate on the mechanical properties of X80 pipeline steel were investigated by slow strain rate test (SSRT), Charpy impact test, and scanning electron microscopy (SEM) in this thesis. The results show that both the ultimate tensile strength and elongation to failure of X80 steel were deteriorated significantly after charging with hydrogen. With a strain rate of 5 x 10-5 s-1, the relative tensile strength and plasticity loss of X80 steel had no significant change within the range of assumed hydrogen partial pressures at room temperature. At room temperature, X80 steel had no apparent variation in ultimate tensile strength and elongation, except at the strain rate of 10-6 s-1. Specimens obtained the greatest relative tensile strength loss and plasticity loss when strained at 10-6 s-1 with a current density of 4.6 mA/cm2. The fracture morphology of two test groups of X80 steel exhibited significant brittle rupture when tested with dynamic hydrogen charging. The impact energy of X80 was not affected by hydrogen charging. Different current density also had no influence on the results of the impact test.

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Sánchez, Vivas Lorena. "Bamboo as a Sustainable Engineering Material: Mechanical Properties, Safety Factors, and Experimental Testing." Scholar Commons, 2019. https://scholarcommons.usf.edu/etd/7925.

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With exponential global population growth occurring and associated environmentally destructive consumption of natural resources, alternative materials that are fast growing and sustainable are being sought out to satisfy human needs. One material that is fast growing and sustainable that can be used to meet most basic needs of humans (i.e. shelter, food, tools) is the plant bamboo, of the grass family Poaceae. Bamboo was used in the past by native peoples who lived in the environment where bamboo natively grows (all continents except Europe and Antarctica) with proven success for uses such as shelter, piping, tools, wells, food, fencing, baskets and much more. These practices were mostly abandoned and deemed obsolete due to the introduction of long lasting ‘modern’ building materials of steel and concrete which gained popularity in the 1800s. Now, in the current century with much advancement in science, technology, and education, humanity is reconsidering many practices and returning to more ancient practices and ways that are better for human health, the environment, and overall sustainability. These environmental considerations are drivers of this research, which focuses on how to use bamboo for engineering applications. First, in order to use a material for engineering and design applications, a material must be destructively tested to attain material property values. Therefore, a critical examination of the bamboo mechanical property values published literature was performed. It was found that although many scientists all over the world have been working on mechanical property testing of bamboo, their results have been published in different journals, in different languages, and had not yet been aggregated and compared. This led to the first study in this work that analyzed mechanical property data from 43 bamboo peer-reviewed publications written in English, Spanish, and Portuguese (the three main languages in which bamboo literature is published). This study focused on aggregating mechanical property values, establishing a range of values for each property as well as an average, and correlating the difference in property values to bamboo variables stated in bamboo literature (age, bamboo species, density, moisture content, post-harvest treatment, and testing standard employed). The five mechanical properties reviewed were: shear strength, compressive strength, tensile strength, bending strength / modulus of rupture (MOR), and modulus of elasticity (MOE) and their average values were 9 MPa, 52 MPa, 159 MPa, 120 MPa, and 16 GPa, respectively. Although a thorough graphical set of analyses were performed attempting to correlate the difference in mechanical property values to the previously listed variables, and only main variables found to influence strength values were moisture content and specific testing standard employed. The results of the high range of mechanical property values with no variable with which to separate the results to lower the range, led to the second part of the research. It incorporated the high range of values reported in the literature but was able to establish safety factors and reduction factors alongside corresponding failure rates. This work allows for a designer to use bamboo culms choosing a failure rate he/she deems appropriate for structural bamboo construction. The analyses in this work were performed using Allowable Stress Design (ASD) and Load and Resistance Factor Design (LRFD) equations applied to bamboo as well as Monte Carlo statistical analyses for verification. The raw data and statistically analyzed data of 25 publications were used for this analysis, yielding 3806 strength test values (shear strength, compressive strength, bending strength / modulus of rupture, and tensile strength). Shear strength safety factors ranged from 1.38-3.58 for failure ratios from 1:6-1:25000; compressive strength from 1.30-2.79; bending strength from 1.43-4.03; tensile strength from 1.66-7.43. No singular safety factor is suggested for design as that is due to the judgment of the designer of what failure ratio he/she deems appropriate for the specific application. Although many compression tests have been performed on bamboo, there are no known tests which destructively test bamboo after an extended period of time after harvesting (more than ~3 months). This experiment conducted a field experiment to test the functionality of using bamboo for the application of installing bamboo wells to provide groundwater. The bamboo tested in the third part of the study was of two species, Dendrocalamus giganteus and Dendrocalamus asper half of which were 1) air-dried in a laboratory for 3.5 years and the other half of which was 2) inserted in the ground as bamboo wells. The bamboo culms (or poles) had been separately treated in three different ways right after cutting: 1/3 with a borax and boric acid solution (most conventional treatment in the industry), 1/3 with coconut oil (experimental treatment in the literature), and 1/3 air-dried, a non-treated control. Bamboo wells are said to be used in ancient times as well as in more recent applications in the 1990s in India by small scale farmers. The publication of bamboo well studies have been very few and nearly no scientific analyses had been performed on them. Therefore, six bamboo wells were assembled and installed at the University of South Florida Geopark, the first of their kind in the U.S. These wells were half of species D. giganteus and half of species D. asper and also treated individually using the three different treatments described above. The wells were monitored for pH and presence of leached boron for a 3.5-year monitoring period and then removed. Upon removal, the bamboo well casings were examined for molds present as well as by mechanical compression testing to assess degradation in comparison to each other (of different treatments) and to air-dried control samples maintained in the laboratory for 3.5 years. The mold fc. Acrodictys was observed to cover the entire inner portion of the bamboo (inner diameter), from the surface level up to the water table. The lab air-dried control samples had compression strength and compressive modulus of elasticity values correlating to those found in the literature, 44-90 MPa (72 MPa average) and 15-31 GPa, respectively. Removed well samples exhibited compressive strengths and compressive modulus of elasticity values of 22-61 MPa (39 MPa average) and 7-25 GPa, respectively. This study revealed that bamboo wells were feasible and although their compressive strengths lowered by around a half after being in the ground for 3.5 years, their compressive strength and compressive modulus of elasticity values were still in the range of bamboo tested in the literature.

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Toledo, García Gustavo A. "High temperature compression testing of hardened steels for plasticity behavior modeling." Thesis, Georgia Institute of Technology, 2002. http://hdl.handle.net/1853/16909.

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Dickinson, A. J. "Examination of the effects of processing variables on the mechanical properties of HDPE." Thesis, Manchester Metropolitan University, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.376539.

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Conley, Jill Anne. "Hygro-thermo-mechanical behavior of fiber optic apparatus." Thesis, Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/17308.

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黃翠 and Cui Huang. "Physical and mechanical properties of some resin-based restorative materials after immersion in two different media." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B38628090.

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Hagg, Lobland Haley E. "Definition of Brittleness: Connections Between Mechanical and Tribological Properties of Polymers." Thesis, University of North Texas, 2008. https://digital.library.unt.edu/ark:/67531/metadc9097/.

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The increasing use of polymer-based materials (PBMs) across all types of industry has not been matched by sufficient improvements in understanding of polymer tribology: friction, wear, and lubrication. Further, viscoelasticity of PBMs complicates characterization of their behavior. Using data from micro-scratch testing, it was determined that viscoelastic recovery (healing) in sliding wear is independent of the indenter force within a defined range of load values. Strain hardening in sliding wear was observed for all materials-including polymers and composites with a wide variety of chemical structures-with the exception of polystyrene (PS). The healing in sliding wear was connected to free volume in polymers by using pressure-volume-temperature (P-V-T) results and the Hartmann equation of state. A linear relationship was found for all polymers studied with again the exception of PS. The exceptional behavior of PS has been attributed qualitatively to brittleness. In pursuit of a precise description of such, a quantitative definition of brittleness has been defined in terms of the elongation at break and storage modulus-a combination of parameters derived from both static and dynamic mechanical testing. Furthermore, a relationship between sliding wear recovery and brittleness for all PBMs including PS is demonstrated. The definition of brittleness may be used as a design criterion in selecting PBMs for specific applications, while the connection to free volume improves also predictability of wear behavior.

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Soonangi, Ganesh Prakruthi. "REVIEW OF DENTAL CROWNS AND THEIR WEAR TESTING." OpenSIUC, 2020. https://opensiuc.lib.siu.edu/theses/2760.

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The desire to replace missing teeth with the aim to improve health and quality of life dates back to a thousand years ago. Although research on dental crown designs, materials and techniques has increased in recent years and is expected to grow in the future. In the past few decades, dental crown studies have gained high importance in dentistry due to their functionality, biocompatibility and good mechanical properties. This paper provides a comprehensive review of history and evolution of dental crowns. The goal of this study is to understand the dental crown materials and the differences in their properties with goals to facilitate the optimal selection and to support further development. It also describes the different methods by which wear is tested on these crowns. Finally, it describes the current technologies used for the analysis, and a comparative study is performed on various dental crown materials and it is demonstrated that the wear resistance is different for different materials.

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Stepto, Simon. "The effect of fibre volume on the mechanical properties of woven composite materials." Thesis, Queen's University Belfast, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.314218.

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Griggs, David Allen. "A laser-based ultrasonic system to measure the mechanical properties of paper products in a controlled environment." Thesis, Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/16801.

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Ruys, David Julian Materials Science &amp Engineering Faculty of Science UNSW. "The influence of bast fibre structure on the mechanical properties of natural fibre composites." Awarded by:University of New South Wales. Materials Science & Engineering, 2007. http://handle.unsw.edu.au/1959.4/40688.

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Composite materials based on natural bast fibres offer potential commercial and environmental benefits due to the low cost, availiability, and biodegradability of the fibres. However, such benefits cannot be realised without a comprehensive evaluation of processing and properties. This thesis involved a comprehensive evaluation of composites based on two types of natural bast fibre (hemp and flax), and two types of matrix - synthetic (epoxy), and biodegradable (Novamont Mater-Si). The experimental work involved four strands: the effects of growing conditions and fibre processing on the properties of raw bast fibres; the optimisation of a pultrusion process for epoxy-matrix composites; development of a film stacking process for Mater-Bi composites, and a detailed evaluation of the mechanical properties of the composites themselves. Fibre bundles and individual fibre cells were investigated to characterise their structure, with particular focus on compressive kink defects. The kink bands were sectioned using a novel technique of focused ion beam milling, and kinking was found to induce delamination and voiding of the lamellar fibre structure. The defect concentration per unit length was assessed for conventionally-processed fibres and for hemp fibres from plants grown under controlled conditions to assess the effect of wind shear and stem flexure on fibre defect concentration. No effect was found for plant flexure, while industrially processed fibre was found to have increased defect concentration. The loading behaviour of both types of composite was seen to be initially linear with a yield point at 20 - 30 MPa and a transition to nonlinear deformation dominated by damage mechanisms as a result of fibre kinks. Epoxy composites possessed an inital modulus of 30 GPa with a 30 - 60% reduction in modulus after yield. Flax reinforcement was found to increase the modulus of Mater-Bi from 0.1 to 20 GPa and strength from 24 to 169 MPa. Fibre addition was also found to significantly embrittle the polymers.

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31

Johnson, Mont A. "Investigation of the mechanical properties of copy paper using laser generated and detected lamb waves." Diss., Georgia Institute of Technology, 1996. http://hdl.handle.net/1853/16730.

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32

Lu, Yuebin. "The application of microindentation testing to measure the inhomogeneity of mechanical properties in polymers." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0007/MQ42243.pdf.

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Merle, Benoit [Verfasser], and Mathias [Akademischer Betreuer] Göken. "Mechanical Properties of Thin Films Studied by Bulge Testing / Benoit Merle. Betreuer: Mathias Göken." Erlangen : Universitätsbibliothek der Universität Erlangen-Nürnberg, 2013. http://d-nb.info/103724320X/34.

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34

C̆yz̆iūtė, Brigita Abakevic̆ienė. "Processes of deposition and testing of mechanical properties of polymers and metal coated polymers." Poitiers, 2008. http://theses.edel.univ-poitiers.fr/theses/2008/Abakeviciene-Cyziute-Brigita/2008-Abakeviciene-Cyziute-Brigita-These.pdf.

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The Ph. D. Work objective was the measurements of the mechanical properties of polymer foils and metal coated polymers, in connection with their microstructures. Two similar micro-tensile deformation devices were developed, which differ by their original non-contact deformation measurement techniques that are electronic speckle pattern interferometry and optical mark-tracking, at the Universities of Kaunas and Poitiers, respectively. The elongation range of both equipments allows for the investigation of elastic and plastic properties of polymer foils, coated polymer foils with thin metallic films. The substrates were either Kapton® HN or PET foils that were coated by electron beam evaporation with Al, Ag, Cr and Ni 0. 5 thick thin films on both sides. The Young’s moduli of the metallic thin films (Ef) were deduced from the stress-strain curves of the substrates and of the metallic/substrate composites. For Al and Ag, the deduced Ef values are in good agreement with those of bulk materials (Eb), while the Ef values for Ni and Cr are found drastically smaller than those of Eb. It was however observed that the Al and Ag metallic layers were uniform, whereas Ni and Cr films were far less regular and exhibit cracks. The microstructures and metal/polymer interfaces were essentially studied on the Ag/PET system. The influence of metal coverage on interface composition, structure, morphology and particle size has been studied by X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM) and X-ray diffraction (XRD). In addition, the role of deposition temperature over the temperature range 20°C-140°C, i. E. Below and above Tg (Tg = 80°C is the PET glass transition temperature), was also examined to understand how microstructure, residual stress, chemical composition and morphology of the Ag/PET layer structure is affected. It was observed that Ag 1 μm thick films evaporated at different temperatures show a compressive stress state with either a (111) texture component below Tg or a random grain orientation above Tg. The texture is formed at the very early stage of growth, at a thickness of nearly 20 nm where the Ag film is still discontinuous. Within the investigated temperature range, the Ag grain size does not depend on the deposition temperature and the deposited films are mostly composed of pure Ag with partially oxidized surface
Le but de ce travail de thèse était de caractériser, en relation avec leurs microstructures, les propriétés mécaniques de films polymères seuls ou revêtus de films minces de matériaux métalliques. Pour cela, deux micromachines de déformation très similaires ont été développées à l'Université de Kaunas et de Poitiers, qui se différencient par leur technique de mesure de déformation sans contact avec l'échantillon, à savoir respectivement la technique par interférométrie de granularité laser et celle de suivi de marqueurs par corrélation d'images. Les élongations permises par les deux équipements autorisent l'étude de la déformation à la fois élastique et plastique des films polymères et polymères revêtus de films minces métalliques. Les substrats ont été des films de Kapton® HN ou de PET revêtus par évaporation par canon à électrons sur chaque face de films minces de Al, Ag, Cr et Ni de 0. 5 μm d'épaisseur. Les modules d'Young (Ef) des couches métalliques ont été déduits des courbes contrainte-déformation des films polymères seuls et revêtus. Pour les films d'Al et Ag, les valeurs de Ef calculées sont en bon accord avec celles couramment rapportées dans la littérature pour les matériaux massifs (Eb), tandis que pour Ni et Cr les valeurs de Ef sont nettement plus faibles que celles de Eb. Il a été corrélativement observé que les couches d'Al et d'Ag étaient uniformes, tandis que celles de Ni et Cr étaient nettement plus irrégulières et présentaient des fissures. Les microstructures et les interfaces métal/polymère ont été principalement étudiées pour le système Ag/PET. L'influence de la couverture métallique sur la composition de l'interface, sa structure, sa morphologie et la taille des particules a été étudiée par XPS, AFM et XRD. De plus, le rôle de la température de dépôt a été étudié sur une plage allant de 20°C à 140°C, c'est-à-dire en dessous et au-dessus de la température de transition vitreuse, Tg = 80°C pour le PET, afin de comprendre mieux comment la microstructure, les contraintes internes, la composition chimique et la morphologie du système Ag/PET peuvent être influencées. Les films d'Ag de 1μm d'épaisseur évaporés à différentes températures sont en compression, texturés (111) au dessous de Tg et non texturés au dessus. La texturation existe dès le début de la croissance du film, à une épaisseur de 20 nm lorsque le film est encore discontinu. Sur la plage de température étudiée, la taille des grains d'Ag ne dépend pas de la température de déposition et les films déposés sont majoritairement composés d'Ag pur avec une oxydation partielle de surface

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35

Xie, Weidong. "Thermo-mechanical evaluation of interfacial integrity in multilayered microelectronic packages." Diss., Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/17380.

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36

Powley, Nicholas R. (Nicholas Ransom) 1982. "A device for testing the electronic and mechanical properties of conducting polymers with electron paramagnetic resonance spectroscopy." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/32776.

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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2004.
Includes bibliographical references (leaf 35).
Conducting polymers have the potential to serve the technical and commercial communities with novel actuators, sensors, and biomimetic devices. The conjugated structures of these polymers and the addition of dopants enable conduction. [1] One current goal in the conducting polymer field is to observe and understand the events by which these polymers carryout their active mechanical functions (contraction and expansion) upon the application of a potential. This thesis presents the design and a prototype of a new device for investigating the relationship between the mechanical and electronic properties of conducting polymers with EPR Spectroscopy. The performance of the testing device was explored with a controlled experiment. The results of this experiment suggest that the response of conducting polymer actuators to mechanical inputs can be examined with EPR Spectroscopy.
by Nicholas R. Powley.
S.B.

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37

Del, Zio Michael R. (Michael Robert) 1982. "Design and testing of the thermal properties of the structure of an ultra high-throughput mutational spectrometer." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/32822.

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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2004.
Includes bibliographical references (leaves 42-43).
A process known as mutational spectrometry allows the detection of both single and multiple mutations that appear to be spontaneous, using a technique known as constant denaturing capillary electrophoresis (CDCE). CDCE requires a region of constant temperature and concentration of denaturant. A massively parallel, fully automated instrument, capable of handling as many as 10,000 DNA samples simultaneously, is suited to this technique. A modular structure of such a mutational spectrometer was designed to remain water-tight, provide an array to hold the capillaries for electrophoretic excitation, and modulate the flow of a heat transfer fluid. Six such modules were manufactured and assembled. As the heat transfer fluid passed through the assembled structure, the natural thermal loss was determined.
by Michael R. Del Zio.
S.B.

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38

Saarimäki, Jonas. "The mechanical properties of lattice truss tructures with loadbearing shells made of selectively laser melted Hastelloy X (TM)." Thesis, KTH, Industriell produktion, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-41320.

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This thesis discusses how to test the mechanical properties of openlattice truss structures and hybrids being a tube containing a latticetruss structure. By properties we mean strength, stiffness, thermalconductivity and so forth.Mechanical testing was done on two different structures to betterunderstand how the load-bearing properties change when these structuresare subjected to tensile, compressive and bending forces. The structuresinvestigated were Diamond and Octagon built at 45° and 90°. Acousticemission was also used to evaluate and analyze the different behaviour ofthe structures. The test results were used to produce design criteria forproperties in different cell structures manufactured of Hastelloy X™. Amap with design criteria containing stiffness and weight per cubiccentimetre was produced for parts that would be subjected to compressiveforces.

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39

Clarke, Andrew Bryson. "Mechanical properties and process conversion of a novel form of unidirectional carbon fibre/epoxy rod." Thesis, University of Bristol, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.267007.

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40

Jayaraman, Vikram. "Production, characterization and testing of Tempered Martensite Assisted Steels (TMAS) obtained via subcritical annealing of cold rolled TRIP steels." Thesis, McGill University, 2007. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=99769.

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The requirement for lighter, safer and fuel efficient cars has created a major stir in the steel research society to develop advanced automotive steels. Since there is a trade off between strength and ductility, most of the conventional high strength steels do not address the strength-formability combination. With the realization of the TRIP phenomenon first in austenitic stainless steels, a new generation of advanced steels called TRIP steels were realised with an inexpensive and easier to process C-Mn-Si chemistry. TRIP or TRransformation Induced Plasticity is a phenomenon where the timely strain induced transformation of Retained Austenite (RA) to Martensite locally strengthens the steel at the point of plastic instability, causing failure by necking to be postponed and shifted elsewhere along the steel. This phenomenon repeated over and over again allows increased levels of strength and ductility, prior to fracture.
In current TRIP grades, the retained austenite particles present have to posses certain characteristics such as, optimum carbon concentration, optimum grain size and morphology etc. in order to account toward mechanical properties. Such limiting characteristics in turn minimize the processing window and make TRIP processing expensive and difficult to control. In this work, it is suggested that Tempered Martensite Assisted Steels (TMAS) obtained from TRIP steels via subcritical annealing of cold rolled TRIP steels may potentially replace TRIP steels. Relationship between the retained austenite volume fractions and mechanical properties was developed for TRIP steels. The effect of variation of retained austenite on tempered martensite volume fraction in TMAS, which in turn affect the mechanical properties was also investigated in depth. Results indicate that tempered martensite particles in TMAS do not have any limiting factors as in the case of RA in TRIP steels, in order to contribute toward enhancement of mechanical properties. Results also indicate that TMAS offers better strength levels compared to TRIP steels for same the level of formability.
Retained austenite volume fractions in TRIP steels were measured through XRD. Cold rolling of the samples was done in a laboratory scale rolling machine. The microstructures were analysed using conventional and color etching techniques. A new color etching technique for viewing all the four major phases in TRIP steel was developed in this work. The mechanical properties of both TRIP and TMAS were assessed by shear punch testing. And finally, the relationship between tempered martensite volume fraction and TMAS properties was developed and was compared to TRIP properties.

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PINTO, JOAO M. A. "Modelagem de testes acelerados com esforco aplicado em niveis em um estudo de fadiga mecanica." reponame:Repositório Institucional do IPEN, 2004. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11245.

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Made available in DSpace on 2014-10-09T12:49:53Z (GMT). No. of bitstreams: 0
Made available in DSpace on 2014-10-09T14:03:05Z (GMT). No. of bitstreams: 1 10187.pdf: 6151210 bytes, checksum: 37ed33ce82293706cac21bb2e41e8dbe (MD5)
Tese (Doutoramento)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

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42

Wong, Kong-yeung, and 黃剛揚. "Development of high strength concrete for Hong Kong and investigation of their mechanical properties." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1996. http://hub.hku.hk/bib/B31213765.

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Dike, Nnadozie N. F. "Performance of Mechanical and Non-mechanical Connections to GFRP Components." Master's thesis, University of Central Florida, 2012. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5187.

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There are presently many solutions to dealing with aging or deteriorated structures. Depending on the state of the structure, it may need to be completely over-hauled, demolished and replaced, or only specific components may need rehabilitation. In the case of bridges, rehabilitation and maintenance of the decks are critical needs for infrastructure management. Viable rehabilitation options include replacement of decks with aluminum extrusions, hybrid composite and sandwich systems, precast reinforced concrete systems, or the use of pultruded fiber-reinforced polymer (FRP) shapes. Previous research using pultruded glass fiber-reinforced polymer (GFRP) decks, focused on behaviour under various strength and serviceability loading conditions. Failure modes observed were specific to delamination of the flexural cross sections, local crushing under loading pads, web buckling and lip separation. However certain failure mechanisms observed from in-situ installations differ from these laboratory results, including behaviour of the connectors or system of connection, as well as the effect of cyclic and torsional loads on the connection. This thesis investigates the role of mechanical and non-mechanical connectors in the composite action and failure mechanisms in a pultruded GFRP deck system. There are many interfaces including top panel to I-beam, deck panel to girder, and panel to panel, but this work focuses on investigating the top panel connection. This is achieved through comparative component level shear, uplift, and flexure testing to characterize failure and determine connector capacity. Additionally, a connection of this GFRP deck system to a concrete girder is investigated during the system-level test. Results show that an epoxy non-mechanical connection may be better than mechanical options in ensuring composite behaviour of the system.
ID: 031001297; System requirements: World Wide Web browser and PDF reader.; Mode of access: World Wide Web.; Title from PDF title page (viewed March 7, 2013).; Thesis (M.S.)--University of Central Florida, 2012.; Includes bibliographical references (p. 80-82).
M.S.
Masters
Civil, Environmental, and Construction Engineering
Engineering and Computer Science
Civil Engineering; Structural and Geotechnical Engineering

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44

Doane, John William. "Measurements on the condition of compliant coatings for prediction of acoustic performance." Thesis, Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/17588.

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45

Esterly, Daniel Mason. "Manufacturing of Poly(vinylidene fluoride) and Evaluation of its Mechanical Properties." Thesis, Virginia Tech, 2002. http://hdl.handle.net/10919/34677.

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Poly(vinylidene fluoride) (PVDF) receives an increasing amount of attention because it exhibits the strongest piezoelectric response of any commercially available polymer. These piezoelectric properties have proved useful as actuators and sensors. Current manufacturing processes limit PVDF to thin films and restricting their uses largely to sensors. Further applications utilizing the changes in mechanical properties of piezoelectric polymers are being realized. Evaluating to what extent the mechanical properties will change with applied electric field and finding new ways to manufacture PVDF will lead to new applications of piezoelectric polymers. In-situ mechanical testing of biased piezoelectric PVDF films successfully measured changes in loss and storage modulus. In-situ creep testing measured an increase in stiffness while in-situ dynamic mechanical analysis (DMA) measured and overall decrease in loss and storage modulus. Differences in results between the two experiments are attributed to orientation of the polymer and piezoelectric forces acting on the equipment. DMA results are accepted as being the most accurate and measured changes of over 20% in elastic modulus. Results were believed to be greatly influence by attached electrodes and actuation forces. Cryogenic mechanical milling successfully converted a phase PVDF powder to b phase as measured with wide-angle x-ray diffraction. This is the first recorded instance of b phase powders forming from the a phase through ball milling. These b phase powders maintained their crystal structure during compression molding at 70°C.
Master of Science

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46

Berry, Robert D. "Dynamic viscoelastic properties of advanced magnetic tapes." Scholarly Commons, 2012. https://scholarlycommons.pacific.edu/uop_etds/807.

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The purpose of this thesis is to analyze the viscoelastic properties of current large digital storage magnetic tape materials, using a custom ultra-low frequency dynamic mechanical analyzer (DMA). Through the correlated effects of frequency and temperature, the long term mechanical properties of the magnetic tape can be simulated and used for predictive analysis of long term storage quality and stability of each individual tape given applicable storage conditions. Two magnetic tapes of primary interest reviewed in this paper are both current leading high capacity tapes, one having a poly(ethylene naphthalate) or PEN substrate and the other an aromatic polyamide or ARAMID substrate. The phase angle between the two signals and the peak strain based elastic modulus (E) were then used to determine the storage modulus (E'), loss modulus (E"), and the loss tangent (tan 8). These viscoelastic characteristics of the material were determined for each individual experimental sample. The combined data was then used to create comparative plots of each sample type allowing for a more conclusive look at the magnetic tape properties under the given conditions. It is found that viscoelastic deformation, or energy loss in the material, increasingly occurs at low frequencies. These experiments also verify that viscoelastic loss also occurs due to molecular orientation and can have a large impact on results. A final comparison is also made between the two leading tape materials commonly used in industry currently by taking a direct look at relative loss in conjunction with the materials overall complex elastic modulus. This allows a more definitive strength comparison of the defined materials · under given conditions.

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Thapa, Keshab Bahadur. "An Investigation of the Mechanical Properties of Swelling Clays and Clay-Kerogen Interactions in Oil Shale: A Molecular Modeling and Experimental Study." Diss., North Dakota State University, 2020. https://hdl.handle.net/10365/31719.

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This work provides an insight into how the molecular interactions influence macroscale properties of two materials: swelling clay and oil shale. Swelling clays cause enormous damage to infrastructure: buildings, roads, and bridges. Understanding the mechanisms are essential to prevent the detrimental effects and use of these clays for engineering applications. Our group studied the effect of fluid polarity on sodium montmorillonite (Na-MMT) swelling clay mineral using molecular modeling and experiments for bridging the molecular level behavior with the microstructure, swelling pressure, permeability, and compressibility. Various polar fluids (Dielectric Constant 110 to 20) found in landfill leachates are used. Our molecular dynamics (MD) simulations show that the nonbonded interactions of Na-MMT with polar fluids are higher than with low and medium polar fluids. These results are consistent with the results from Fourier transform infrared (FTIR) spectroscopy experiments. The polarity of the fluids and the fluid content influence the interlayer spacing, interlayer modulus, nonbonded interactions, and conformation as well as the shear strength parameters, the angle of internal friction (φ) and cohesion (c). Furthermore, the unconfined compressive strength experiments are used to evaluate the undrained cohesion at various swelling level. The nanomechanical properties, the modulus of elasticity (E) and hardness (H), of the undisturbed dry and saturated Na-MMT at various level of swelling are evaluated using nanoindentation experiments for the first time. The undrained cohesion, modulus of elasticity, and hardness decrease with increase in swelling level. Swelling controls the microstructure of Na-MMT clay, and the clay particles breakdown into smaller sizes with increase in swelling level. The Green River Formation located in the United States is the richest oil shale deposit in the world. Oil shale contains clay minerals, bitumen, and kerogen—a precursor to crude oil. A three-dimensional (3D) kerogen model is built from seven fragments, and the interactions of kerogen with Na-MMT is investigated using MD simulations to understand how the kerogen is bound to the clay mineral. The nonbonded interactions between Na-MMT and kerogen as well as among kerogen fragments are found. This work seeks to develop new methods to extract kerogen economically and efficiently.
Department of Energy (DoE)
Mountain Plains Consortium (MPC)
North Dakota Established Program to Stimulate Competitive Research (ND EPSCoR)

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48

Kabche, Jean Paul. "Structural Testing and Analysis of Hybrrid Composite/Metal Joints for High-Speed Marine Structures." Fogler Library, University of Maine, 2006. http://www.library.umaine.edu/theses/pdf/kabchejp2006.pdf.

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Shirmohammadi, Maryam. "Process modelling and simulation of tissue damage during mechanical peeling of pumpkin as a tough skinned vegetable." Thesis, Queensland University of Technology, 2014. https://eprints.qut.edu.au/67921/1/Maryam_Shirmohammadi_Thesis.pdf.

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Food waste is a current challenge that both developing and developed countries face. This project applied a novel combination of available methods in Mechanical, agricultural and food engineering to address these challenges. A systematic approach was devised to investigate possibilities of reducing food waste and increasing the efficiency of industry by applying engineering concepts and theories including experimental, mathematical and computational modelling methods. This study highlights the impact of comprehensive understanding of agricultural and food material response to the mechanical operations and its direct relation to the volume of food wasted globally.

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Stagon, John Thomas. "The Mechanical Property Analysis of Thin Diamond Coated Metal Substrates." Case Western Reserve University School of Graduate Studies / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=case1337013344.

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Dissertations / Theses on the topic 'Shale Mechanical properties Testing'

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