Dissertations / Theses on the topic 'Assissing the strength of a material'
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Ribeiro-Ayeh, Steven. "On the strength of bi-material interfaces." Licentiate thesis, KTH, Aeronautical Engineering, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-1467.
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Du, Lianxiang. "Laboratory investigations of controlled low-strength material." Access restricted to users with UT Austin EID Full text (PDF) from UMI/Dissertation Abstracts International, 2001. http://wwwlib.umi.com/cr/utexas/fullcit?p3031045.
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Larsson, Rikard. "On Material Modelling of High Strength Steel Sheets." Doctoral thesis, Linköpings universitet, Hållfasthetslära, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-80115.
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The work done in this thesis aims at developing and improving material models for use in industrial applications. The mechanical behaviour of three advanced high strength steel grades, Docol 600DP, Docol 1200M and HyTens 1000, has been experimentally investigated under various types of deformation, and material models of their behaviour have been developed. The origins of all these material models are experimental findings from physical tests on the materials. Sheet metal forming is an important industrial process and is used to produce a wide range of products. The continuously increasing demand on the weight to performance ratio of many products promotes the use of advanced high strength steel. In order to take full advantage of such steel, most product development is done by means of computer aided engineering, CAE. In advanced product development, the use of simulation based design, SBD, is continuously increasing. With SBD, the functionality of a product, as well as its manufacturing process, can be analysed and optimised with a minimum of physical prototype testing. Accurate numerical tools are absolutely necessary with this methodology, and the model of the material behaviour is one important aspect of such tools. This thesis consists of an introduction followed by five appended papers. In the first paper, the dual phase Docol 600DP steel and the martensitic Docol 1200M steel were subjected to deformations, both under linear and non-linear strain paths. Plastic anisotropy and hardening were evaluated and modelled using both virgin materials, i.e. as received, and materials which were pre-strained in various material directions. In the second paper, the austenitic stainless steel HyTens 1000 was subjected to deformations under various proportional strain paths and strain rates. It was experimentally shown that this material is sensitive both to dynamic and static strain ageing. A constitutive model accounting for these effects was developed, calibrated, implemented in a Finite Element software and, finally, validated on physical test data. The third paper concerns the material dispersions in batches of Docol 600DP. A material model was calibrated to a number of material batches of the same steel grade. The paper provides a statistical analysis of the resulting material parameters. The fourth paper deals with a simple modelling of distortional hardening. This type of hardening is able to represent the variation of plastic anisotropy during deformation. This is not the case with a regular isotropic hardening, where the anisotropy is fixed during deformation. The strain rate effect is an important phenomenon, which often needs to be considered in a material model. In the fifth paper, the strain rate effects in Docol 600DP are investigated and modelled. Furthermore, the strain rate effect on strain localisation is discussed.SFS ProViking Super Light Steel Structures
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Logan, Andrew Thomas. "Short-Term Material Properties of High-Strength Concrete." NCSU, 2005. http://www.lib.ncsu.edu/theses/available/etd-07252005-220433/.
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The need to extend the applicability of the AASHTO LRFD Bridge Design Specifications to high-strength concrete is being addressed by a series of projects being sponsored by the National Cooperative Highway Research Program (NCHRP). Among these projects, NCHRP Project 12-64 is being carried out at North Carolina State University (NCSU) to expand the use of the design specifications to 18,000 psi (124 MPa) for reinforced and prestressed concrete members in flexure and compression. As a part of this project, specimens were tested to determine the material properties of three high-strength concrete mixtures having target compressive strengths of 10,000, 14,000, and 18,000 psi (69, 97, and 124 MPa). The effects of various curing methods were also studied. This study covers the compressive strength, elastic modulus, Poisson?s ratio, and modulus of rupture of high-strength concrete. The study showed that extended curing beyond 7 days resulted in little or no increase in compressive strength. For predicting the elastic modulus of high-strength concrete, the ACI 318-02 or AASHTO-LRFD equation over-estimates the actual modulus while the ACI 363R-92 equation adequately predicts the measured value. The modulus of rupture equation in ACI 318-02 or AASHTO-LRFD gives a good approximation of the modulus of rupture of high-strength concrete when 1-day heat curing and 7-day moist curing are used. The equation from ACI 363R-92 gives a good estimate of modulus of rupture values for continually moist-cured specimens. The Poisson?s ratio of high-strength concrete is generally within the range of that reported for normal-strength concrete.
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Dan-Jumbo, F. G. "Material and structural properties of a novel Aer-Tech material." Thesis, Coventry University, 2015. http://curve.coventry.ac.uk/open/items/699ca3a1-deec-4549-b907-0e06bcdad83f/1.
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This study critically investigates the material and structural behaviour of Aer-Tech material. Aer- Tech material is composed of 10% by volume of foam mechanically entrapped in a plastic mortar. The research study showed that the density of the material mix controls all other properties such as fresh state properties, mechanical properties, functional properties and acoustic properties. Appreciably, the research had confirmed that Aer-Tech material despite being classified as a light weight material had given high compressive strength of about 33.91N/mm2. The compressive strength characteristics of Aer-Tech material make the material a potential cost effective construction material, comparable to conventional concrete. The material also showed through this study that it is a structural effective material with its singly reinforced beam giving ultimate moment of about 38.7KN. In addition, the Aer-Tech material is seen as a very good ductile material since, the singly reinforced beam in tension showed visible signs of diagonal vertical cracks long before impending rapture. Consequently, the SEM test and the neural network model predictions, carried out had showed how billions of closely tight air cells are evenly distributed within the Aer-Tech void system as well as the close prediction of NN model for compressive strength and density are same with the experimental results of compressive strength and density. The result shows that the Aer-Tech NN-model can simulate inputs data and predicts their corresponding output data.
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Claus, Julien. "Investigations on a new high-strength pozzolan foam material." Thesis, Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/31804.
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Thesis (M. S.)--Civil and Environmental Engineering, Georgia Institute of Technology, 2009.Committee Chair: Doyoyo Mulalo; Committee Member: Will Kenneth; Committee Member: Yavari Arash. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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Howell, Benjamin Paul. "An investigation of Lagrangian Riemann methods incorporating material strength." Thesis, University of Southampton, 2000. https://eprints.soton.ac.uk/47085/.
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The application of Riemann Methods formulated in the Lagrangian reference frame to the numerical simulation of non-linear events in solid materials is investigated. Here, solids are characterised by their ability to withstand shear distortion since they possess material strength. In particular, numerical techniques are discussed for simulating the transient response of solids subjected to extreme loading. In such circumstances, the response of solids will often be highly non-linear, displaying elastic and plastic behaviour, and even moderate compressions will produce strong shock waves. This work reviews the numerical schemes or 'hydrocodes' which have been adopted in the past in order to simulate such systems, identifying the advantages and limitations of such techniques. One of the most prominent limitations of conventional Lagrangian methods is that the computational mesh or grid has fixed-connectivity i.e. mesh nodes are connected to the same nodes for all time. This has significant disadvantages since the computational mesh can easily become tangled as the simulated material distorts. The majority of conventional hydrocodes are also constructed using outdated artificial viscosity schemes which are known to diffuse shock waves and other steep features which may be present in the solution. In the work presented here, a novel two-dimensional Lagrangian solver has been developed Vucalm-EP which overcomes many of the limitations of conventional techniques. By employing the Free-Lagrange Method, whereby the connectivity of the computational mesh is allowed to evolve as the material distorts, problems of arbitarily large deformation can be simulated. With the implementation of a spatially second-order accurate, finite-volume, Godunov-type solver, non-linear waves such as shocks are represented with higher resolution than previously possible with contemporary schemes. The Vucalm-EP solver simulates the transient elastic-perfectly plastic response of solids and displays increased accuracy over alternative Lagrangian techniques developed to simulate large material distortion such as Smoothed particle Hydrodynamics (SPH). Via a variety of challenging numerical simulations the Vucalm-EP solver is compared with contemporary Euler, fixed-connectivity Lagrangian, and meshless SPH solvers. These simulations include the solution of one- and two dimensional shock tube problems in aluminium, simulating the collapse of cylindrical shells and modelling high-velocity projectile impacts. Validation against previously published results, solutions obtained using alternative numerical techniques and analytical models illustrates the versatility and accuracy of the technique. Thus, the Vucalm-EP solver provides a numerical scheme for the Lagrangian simulation of extensive material distortion in materials with strength, which has never previously been possible with mesh-based techniques.
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Asgher, Wasim. "Effect of material grade on fatigue strength and residual stresses in high strength steel welds." Thesis, KTH, Lättkonstruktioner, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-101928.
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This thesis work is concerned with effect of material grade on fatigue strength of welded joints. Fatigue strength evaluation of welded joints in as welded and post weld treated condition was carried out with effective notch method. Results of peak stress method have also been compared with those of effective notch method for as welded joints. In addition, using the results of effective notch method, the effect of important weld and global geometry factors on notch stress concentration factor has been studied with 2-level design of experiment and a mathematical relation among stress concentration factor and the geometric factors has been proposed. Overall, thickness of the base plate and toe radius is found to be the most important factors determining fatigue strength of the joint. Welding induced residual stresses have also been predicted using 2D and 3D FEM analysis to see their effect on fatigue strength of the joints. Also, transversal residual stresses were measured using X-ray diffraction method to assess the accuracy of predicted results. Based on simulation results, effect of geometric factors on maximum value of transversal residual stress was also investigated.
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Leigh, Benjamin David. "Strength degradation of carbon-carbon composites for aircraft brakes." Thesis, University of Bath, 1999. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285332.
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Mirzadeh, Farshad. "Compressive strength and behavior of 8H C3000/PMR15 woven composite material." Diss., Virginia Polytechnic Institute and State University, 1988. http://hdl.handle.net/10919/54337.
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Center-notched and unnotched specimens cut from Celion 3000/PMR15 woven composite panels with 60% fiber volume fraction were tested under quasi-static compressive load to failure at room temperature. Micrographic evidence clearly identifies the mode of compressive failure as fiber kinking. Each fiber in the kink fractures because of a combination of compressive and shear stresses. A post failure mechanism follows the local fiber bundle failures, which completely deforms the material by large cracks. ln center notched specimens, fiber kinks start from the notch and propagate to some distance from the notch before the post failure takes place. The effect of bundle interactions on stresses and strains was clearly distinguished by comparing the results of the finite element analysis of a bundle surrounded by other plies to the results of the Moire interferometry on the edge of a laminate. A model was introduced which incorporated the micromechanical geometry as well as the constituent properties to predict the notched and unnotched compressive strengths of the woven material. For notched strength predictions, the Average Stress Criterion was used, and the characteristic distance was found to be a function of laminate thickness. Predicted notched and unnotched strengths correlate very well with the experimental results.Ph. D.
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Conroy-Jones, Gene A. "The effects of curing, and aggregate type upon the tensile strength measurement of medium to high strength concrete." Thesis, Cardiff University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.301797.
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Phillips, Lakin N. "Evaluation of Ohio Coal as Filler Material for Thermoplastic Composites." Ohio University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1512564409202248.
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Lee, Seunghun Marghitu Dan B. "Impacts of kinematic links with a granular material." Auburn, Ala., 2009. http://hdl.handle.net/10415/1751.
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Acton, Michael Rex. "Experiments on the indentation and strength of diamond." Thesis, University of Oxford, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.256898.
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Taymouri, Farid. "Reference data for bone material strength index (BMSI) measured by impact microindentation." Doctoral thesis, Universitat Autònoma de Barcelona, 2019. http://hdl.handle.net/10803/666868.
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Objetivo: La microindentación de impacto (MII) es una técnica que permite medir in vivo la resistencia tisular mecánica ósea. Se ha demostrado que la MII proporciona información útil sobre la evaluación de enfermedades esqueléticas, pero se desconoce el efecto que la edad puede ejercer sobre la propiedad ósea medida. El objetivo del estudio es analizar la relación entre la edad y la MII.
Material y métodos: El índice de Resistencia Mineral Ósea (BMSi), la variable de medición de MII, se midió en 69 mujeres (mediana de edad: 49 años; rango: 30-81 años) y 19 varones (mediana de edad: 34 años; rango: 24-98 años) sanos. La correlación entre BMSi y la edad se analizó mediante regresión lineal. La asociación entre BMSi y edad se evaluó mediante ANOVA tras ajustar por el índice de masa corporal. El posible efecto de depleción estrogénica postmenopáusica sobre el BMSi se estudió comparando el subgrupo de mujeres más jóvenes con las más mayores mediante la prueba t de Student.
Resultados: Los análisis de regresión lineal mostraron que la BMSi no se correlaciona con la edad en varones (R2=0,0016, p=0,74) ni en mujeres (R'=0,076, p=0,25). Asimismo, el análisis ajustado de ANOVA no demostró asociación entre la BMSi y la edad ni en varones (p=0,78) ni en mujeres (p=0,73). Finalmente, no se encontraron diferencias entre la BMSi entre las mujeres más jóvenes y las mayores (p=0,8). Conclusiones: La resistencia tisular mecánica ósea en individuos sanos es independiente a la edad y a la depleción estrogénica postmenopáusica.Objective: Impact microindentation (IMI) is a technique that allows the measurement of mechanicalbone tissue resistance in vivo. IMI has proven to provide useful information on the evaluation of skeletal diseases, but the effect of age on the bone property that is measured by this technique is unknown. This study aims to analyzethe relationship between age and MIH. Material and methods: Bone Material Strength index (BMSi), IMI's output variable, was measured in 69 healthy women (median age: 49 years, range: 30-81 years) and 19 healthy men (median age: 34 years, range: 24-98 years). The correlation between BMSi and age was analyzed by linear regression. The association between BMSi and age was evaluated by ANOVA after adjusting for body mass index. The potential effect of postmenopausal estrogenic depletion on BMSi was studied by comparing the younger vs the older subset of women through a t-student test. Results: Linear regression analysis showed that BMSi was not correlated with age in either men (R'=0.0016, p=0.74) or women (R'=0.076, p=0.25). Similarly, the BMI-adjusted ANOVA model revealed a lack of association of BMSi with age in men (p=0.78) and women (p=0.73). Finally, there were not significant differences on BMSi detected between the younger and the older subset of women (p=0.8). Conclusions: Bone tissue mechanical resistance in healthy individuals is independent of age and postmenopausal estrogenic depletion.
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Krossa, Alexander. "Material characteristics of new ultra high-strength steels manufactured by Giflo Steels." Thesis, Queensland University of Technology, 2022. https://eprints.qut.edu.au/236243/1/Alexander%2BKrossa%2BThesis%281%29.pdf.
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This thesis has investigated the material characteristics of the new high-strength steel (HSS) produced by Giflo Steels (F-series steel) using detailed experimental studies involving ambient and elevated temperature mechanical property tests, post-fire mechanical property tests and V-Charpy notch tests for hardness. Its findings have shown that the new F-series steel has an advantage over similar HSS as it has superior post-fire mechanical properties, while retaining also the other mechanical properties within the requirements of relevant design standards.
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Larsson, Rikard. "Constitutive Modelling of High Strength Steel." Thesis, Linköping University, Department of Management and Engineering, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-8157.
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This report is a review on aspects of constitutive modelling of high strength steels. Aspects that have been presented are basic crystallography of steel, martensite transformation, thermodynamics and plasticity from a phenomenological point of view. The phenomenon called mechanical twinning is reviewed and the properties of a new material type called TWIP-steel have been briefly presented. Focus has been given on phenomenological models and methods, but an overview over multiscale methods has also been given.
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Zhang, Y. H. "Small fatigue crack growth in high strength aluminium alloys." Thesis, Open University, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.314821.
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Jones, S. P. "Stress-corrosion and exfoliation of high strength aluminium alloys." Thesis, Cranfield University, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.352939.
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Murrell, Pamela. "Fatigue and fracture of a high strength cast steel." Thesis, Cranfield University, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.359549.
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Altzar, Oskar. "Surface Characteristics and Their Impact on Press Joint Strength." Thesis, KTH, Mekanisk metallografi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-205919.
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Press fitting is a commonly used method in the assembly of shafts and gearwheels in gearboxes andare using the friction created between them to hold them together. To increase productivity Scania CVAB in Södertälje, Sweden, are going to replace the current hard machining method for layshafts. Whiletesting the new methods in rig it occurred that the gearwheel slipped in tangential direction towardsthe layshaft at a lower torque then with the current method even through all requirements on thelayshafts surface was meet. The purpose and aim with this study is to investigate differences betweenthe methods and to find new requirements for the layshaft. The torque of slip, (Ms) established in atorque test rig and analysis of surface roughness, hardness and microstructure conducted of both thelayshafts and gearwheels. The characteristics of the layshaft surface was also analysed and comparedbetween the different hard machining methods. The study concludes that no correlation between thesurface parameters and the Ms occurred and no major differences in the material between themethods. The study also concluded that the Ms between the layshaft and gearwheel is lower if thelayshaft surface is harder and smoother than the gearwheel surface.
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Williams, Alun Gwyn. "Studies of muscle strength : with special reference to military training." Thesis, University of Birmingham, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.369339.
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Initially, this research programme investigated training methods to improve strengthrelated material handling performance in the British Army. A widely used training programme was evaluated for its effectiveness in improving material handling, and found to provide some significant but small improvements. Modifications to the training programme, including the use of a large strength-training element, were devised based on prior research evidence. The modified training programme was evaluated and compared with the original programme, and shown to be significantly more effective at improving material handling. Any means to improve the effectiveness of strength training per se would further improve the effectiveness of the modified training programme. Consequently, a potential means to improve the effectiveness of strength training via postexercise nutritional supplementation was investigated. The encouraging but not statistically significant results suggested further research to evaluate the potential of the supplementation regimen and also to better illuminate the possible mechanisms. An evaluation of the hormonal and metabolic responses to varying combinations of resistance exercise and supplementation provided little additional evidence to support the effectiveness of the supplementation regimen. However, the likely mechanism of the effect that may exist was better identified as a direct effect of insulin or amino acid availability on muscle cell growth, rather than a reduction in circulating cortisol concentration.
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Westrin, Pontus, and Nils Melin. "Slope processes and strength of material in silt rich ravines in Säterdalen, Sweden." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-239978.
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Slope processes are important to understand if we are to protect fragile environments. Every year slope development in weak soils put nearby infrastructure in risk zones of sliding and ravine erosion takes away field areal from farmers as they grow even larger. Many methods for doing a risk analysis of a slope and its soil are complicated and require a lot of equipment. A simple way to do a slope investigation is explained in this report, along with its advantages and disadvantages. The authors construct a shear ring, an apparatus to measure peak shear stress of soils before fracturing. LIDAR scanning of two small ravines are also made to illustrate how laser scanning can be used to accurately measure denudation in slopes. The results vary, the shear ring is mostly a success aside from errors caused by difficulty in taking representative samples and disturbance. Some of the laboratory work made to determine material properties fail at giving good results, often a result of bad samples or disturbance in the tests. The LIDAR is determined to be a good instrument when working with slope development.Sluttningsprocesser är viktiga att förstå och studera om vi ska kunna skydda känsliga områden. Varje år så sätter svaga jordar i sluttningar närliggande infrastruktur i riskzonen för att ligga på ett glidplan som snabbt kan släppa om jorden blir för blöt eller om för mycket tyngd läggs ovanpå. Samtidigt så tar ravinerosion bort åkerareal från bönder varje år medan ravinerna blir större och större. Många metoder för att göra riskanalyser av sluttningar är komplicerade och kräver mycket utrustning. I denna rapport så testas ett enkelt sätt att göra en sluttningsanalys med tillhörande diskussion kring dess fördelar och nackdelar. Författarna konstruerar en shear ring, en apparat som används för att testa jordens möjlighet att motstå en applicerad kraft. Två sidoraviner scannas även med LIDAR som en bas för att studera denudation i sluttningar. Resultaten varierar, shear ring-apparaturen bestäms som väl fungerande med undantag från vissa utförda tester, där svårigheter uppstod då jordproverna var störda eller mindre representativa. Vissa av laborationerna på jorden misslyckas med att ge bra värden, vilket ofta är ett resultat av dåliga eller störda prover. Laserscanningar av raviner med LIDAR bestäms som ett bra sätt att studera utvecklingen i sluttningar samt att mäta erosion.
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Bae, Hae Ryong. "Effects of temperature on the tensile strength and elastic modulus of composite material." Thesis, Reading, Mass. : Addison-Wesley, 1985. http://hdl.handle.net/10945/21301.
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Fahad, M. K. "The strength of brittle materials under complex states of stress." Thesis, University of Newcastle Upon Tyne, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.315564.
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Zong, Bernie Yaping. "Strength and fracture of a metal matrix composite at elevated temperature." Thesis, University of Oxford, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.260733.
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Morata, Royes Joan. "Wear resistance of heat-treated Advanced High Strength Steels and casting." Thesis, Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-80526.
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The necessity to improve the durability of the machinery used in the milling industry has lead to several types of research. One study is focused on the plates that are located in the stationary and moving jaws of crushers to diminish particles sizes of Gneiss and Diabase rocks. Thus, one type of approach to increase its durability is by reducing the material loss of the plates. Amongst all the parameters to reduce the wear ratio that includes inputs from geometry to load, just the hardness input of the material can be in constant development. Consequently, there are two well-known types of heat treatment that can produce this change in hardness and are named Carbide Free Bainite (CFB) and Quenching and Partitioning (QP). In this master thesis the topic is to perform the QP heat treatments for two compositions A and B to obtain the microstructure of the steels that consist in a mix of austenite, bainite and martensite which considerably increase the hardness while the toughness is not drastically reduced due to the austenite soft phase. Five samples have been studied at four different partitioning temperatures: QP250 A, QP180 B, QP210 B, QP240 B and Mn Steel as it is the composition most used nowadays in the industry. In order to characterise both mechanical properties and microstructural features, different analysis had been performed with Micro-indentations, Charpy-V, Gouging Abrasion Tests, Optical Microscopy, Scanning Electron Microscopy and X-Ray Diffraction. These analysis had been done in the samples before and after wear as a result in change of the microstructure. As the abrasive-impact of the rocks collide with the sample, austenite transforms to martensite by induced plasticity called TRIP effect. Thus, the surface of the alloy is harder than the bulk material as no austenite is found and the wear ratio is seen to be improved. The results have shown several behaviours. Austenite transforms in its majority to fresh martensite which is an unstable martensitic phase but harder than tempered martensite that is the stable martensitic phase. Moreover, the difference in hardness between the bulk and the surface produce an affected depth layer as a consequence of the abrasive-impact penetration of rocks in which the microstructure has fully transformed to martensite on the surface and the austenite phase increases as it goes further inside the steel. The thinner this layer is, the better wear ratio presents the alloy. From all the samples, the best combination of hardness and toughness is for QP210 B.
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Bursle, Sonia Jean Civil & Environmental Engineering Faculty of Engineering UNSW. "Influence of material related parameters on the axial shortening of high strength concrete columns." Awarded by:University of New South Wales. Civil & Environmental Engineering, 2009. http://handle.unsw.edu.au/1959.4/44512.
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The prediction of axial shortening is necessary in structures sensitive to its effects, such as tall bUildings. Potential strength and serviceability problems associated with axial shortening include damage to the building facade and rigid services such lift gUide rails. Differential shortening between adjacent elements can cause floor flatness problems and excessive additional bending moments and shear forces can be induced in horizontal members. The development of high strength concrete (HSq and the consequent increase in building heights has been rapid with little published information incorporating both axial shortening analysis and HSC material modelling. World Tower, the tallest residential bUilding in the Sydney CBD, presented an opportunity to monitor the axial shortening of HSC vertical elements. Comparison of the measured strains with theoretical predictions allowed the verification of the calculated values. The few buildings previously studied were constructed from normal strength concrete (NSC). This study considers the prediction of axial shortening with emphasis given to the refinement of the concrete material models for compressive strength, elastic modulus, shrinkage and creep. The test results of concrete samples taken from the World Tower building are compared to theoretical models available in design codes and published research. Compressive strength development results were best reflected by the ACI committee 209 (1992) model. An improved prediction was achieved when the actual measured strength was used instead of the specified characteristic strength. An elastic modulus model was developed in this study as most of the models considered overestimated the modulus of HSC. The basic creep factors derived from testing showed reasonable agreement with the creep model proposed by Gilbert (2002). Shrinkage models were reviewed by combining the shrinkage calculated with the verified creep and elastic strains. The shrinkage model proposed by Gilbert (2002) was found to provide the most consistent shrinkage strain prediction. The sensitivity of the results was also considered for it can be detrimental to both over and underestimate the axial strains. Shrinkage was found to influence the overall axial strain significantly compared the to the creep and elastic strain components. Hence, accurate determination of the expected shrinkage behaviour is essential for meaningful results.
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Wagstaff, Kevin Bjorn. "Evaluation of Passive Force on Skewed Bridge Abutments with Controlled Low-Strength Material Backfill." BYU ScholarsArchive, 2016. https://scholarsarchive.byu.edu/etd/5824.
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Although its use has become more widespread, controlled low-strength material, or CLSM, has fallen through the crack between geotechnical engineering and materials engineering research. The National Ready Mix Association states that CLSM is not a low strength concrete, and geotechnical engineers do not consider it as a conventional aggregate backfill. The use of CLSM as a bridge abutment backfill material brings up the need to understand the passive force versus backwall displacement relationship for this application. To safely account for forces generated due to seismic activity and thermal expansion in bridge design, it is important to understand the passive force versus backwall displacement relationship. Previous researchers have pointed out the fallacy of designing skewed bridges the same as non-skewed bridges. They observed that as the bridge skew angle increases, the peak passive force is significantly diminished which could lead to poor or even unsafe performance. The literature agrees that a displacement of 3-5% of the wall height is required to mobilize the peak passive resistance. The shape of the passive force displacement curve is best represented as hyperbolic in shape, and the Log Spiral method has been confirmed to be the most accurate at predicting the peak passive force and the shape of the failure plane. All of the previous research on this topic, whether full-scale field tests or large-scale laboratory tests, has been done with dense compacted sand, dense granular backfill, or computer modeling of these types of conventional backfill materials. However, the use of CLSM is increasing because of the product's satisfactory performance as a conventional backfill replacement and the time saving, or economic, benefits. To determine the relationship of passive force versus backwall displacement for a CLSM backfilled bridge abutment, two laboratory large-scale lateral load tests were conducted at skew angles of 0 and 30°. The model backwall was a 4.13 ft (1.26 m) wide and 2 ft (0.61 m) tall reinforced concrete block skewed to either 0 or 30°. The passive force-displacement curves for the two tests were hyperbolic in shape, and the displacement required to reach the peak passive resistance was approximately 0.75-2% of the wall height. The effect of skew angle on the magnitude of passive resistance in the CLSM backfill was much less significant than for conventional backfill materials. However, within displacements of 4-5% of the backwall height, the passive force-displacement curve reached a relatively constant residual or ultimate strength. The residual strength ranged from 20-40% of the measured peak passive resistance. The failure plane did not follow the logarithmic spiral pattern as the conventional backfill materials did. Instead, the failure plane was nearly linear and the failed wedge was displaced more like a block with very low compressive strains.
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Bandi, Raghava. "Effect of Surface Treatment on the Performance of CARALL, Carbon Fiber Reinforced Aluminum Dissimilar Material Joints." Thesis, University of North Texas, 2017. https://digital.library.unt.edu/ark:/67531/metadc1011869/.
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Fiber-metal laminates (FML) are the advanced materials that are developed to improve the high performance of lightweight structures that are rapidly becoming a superior substitute for metal structures. The reasons behind their emerging usage are the mechanical properties without a compromise in weight other than the traditional metals. The bond remains a concern. This thesis reviews the effect of pre-treatments, say heat, P2 etch and laser treatments on the substrate which modifies the surface composition/roughness to impact the bond strength. The constituents that make up the FMLs in our present study are the Aluminum 2024 alloy as the substrate and the carbon fiber prepregs are the fibers. These composite samples are manufactured in a compression molding process after each pre-treatment and are then subjected to different tests to investigate its properties in tension, compression, flexural and lap shear strength. The results indicate that heat treatment adversely affects properties of the metal and the joint while laser treatments provide the best bond and joint strength.
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Asia, Winifred. "An in-vitro study of the physical properties of core build-up materials." University of the Western Cape, 2017. http://hdl.handle.net/11394/6307.
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Magister Chirurgiae Dentium - MChD (Prosthodontics)The aim of this study was to evaluate and compare the physical properties of two core build-up materials (ParaCore and CoreXflow) and compare this to conventional composite material (Filtek Supreme Plus and SDR Flow) used as core build-up material.
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Chitti, Abhishek. "ASSESS MATERIAL PROPERTIES OF CONCRETE USING COMBINED NDT METHODS." OpenSIUC, 2019. https://opensiuc.lib.siu.edu/theses/2490.
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The aim of this research is to assess the material properties of concrete like modulus of elasticity, compressive strength, and Poisson’s ratio using various nondestructive Testing (NDT) methods like Ultrasonic Pulse Velocity (UPV) and Rebound Hammer (RH). Assessment of material properties of concrete is very important as they are used for structural design process. Various NDT methods are applied to ensure the quality of concrete specimens but they can also be used to find material properties. UPV is a NDT method which is used to test the internal condition of the concrete specimen. RH is a surface hardness testing method and can be used to test the homogeneity of the specimen. For this study, several batches of concrete samples with three different design strengths of 6000 psi, 8000 psi, and 12000 psi were casted. Modulus of elasticity and Poisson’s ratio were calculated from UPV P-wave and S-wave velocities. A Nomogram was developed by combining the longitudinal ultrasonic pulse velocities, rebound numbers, and compressive strengths measured from UPV, RH, and compressive strength tests respectively. This combined NDT correlation curve (Nomogram) can be used to estimate compressive strength of concrete if UPV and rebound values are known. The accuracy of these NDT methods were determined by comparing estimated strength to the actual strength. Furthermore, the effect of moisture content on UPV and rebound values was reviewed and also studied dynamic modulus of elasticity and its relation with static modulus of elasticity of the concrete was investigated for better understanding.
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Wu, Xiao Dong. "Experimental and theoretical studies of corrosion fatigue in a high strength steel." Thesis, University of Sheffield, 1995. http://etheses.whiterose.ac.uk/1846/.
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The present work consists of both experimental and theoretical aspects of corrosion fatigue in a high strength steel. Fatigue tests were conducted under fully reversed shear loading in an aerated 0.6M NaC1 solution at pH6, for a silico-manganese spring steel (BS251A58) having a yield strength around 1400 MPa. The fatigue crack evolution process can be defined sequentially in terms of a pit, a short crack in stage I and a crack in stage II. It was observed that in the early stages pits developed at Mn-rich sulphide inclusions, from which short cracks developed and propagated in stage I; the crack growth rate of such cracks was dominated by microstructural features. Stage II, microstructure-independent crack growth was observed following a transition from stage I crack growth. In addition consideration was given to the influences of cyclic frequency, the effect of cathodic polarisation and the effect of electrolyte compositions on corrosion fatigue lifetime and crack growth behaviour. Mechanical properties, metallurgical and electro-chemical properties of the material used were also investigated. The failed specimens were examined using SEM and X-ray spectra analysis in order to study the failure mechanism. Using a dislocation based Navarro-de los Rios model to represent the crack and its associated plastic zone, the crack growth process is characterised by the interaction of dislocations associated with micro-cracks, or local damage, and microstructural barriers (grain boundaries, precipitates, dispersed particles, phase interfaces, etc.). Some modifications to the model were made to incorporate the corrosive effect on the early stages of crack initiation (i.e. pit growth), the transition of stage I crack growth to stage II crack growth, and strain hardening of a parabolic form in order to achieve a more accurate prediction. The validity of the model was justified by the good agreement achieved between predictions based on the model and the experimental results. Based on the present study the following conclusions were made: 1. The fatigue strength of BS251A58 steel, subjected to 107 cycles in a 0.6M NaC1 solution, at pH6 and at a frequency of 5Hz, is 98 MPa, and is significantly lower than the value of the fatigue limit in air, i.e. 457.5 MPa. 2. Corrosion fatigue crack propagation in the high strength BS251A58 steel can be described sequentially in terms of corrosion-induced pits, microcracks from pits, cracks in stage I (shear type cracks), and cracks in stage II (tensile cracks). 3. The number of cycles in the stage I-to-stage II transition, in relation to the whole fatigue life, varies from 20% to 60%, increasing as the applied load decreases. 4. Crack coalescence may occur in both the stage I and stage II regimes. In the stage I regime, microcracks with an effective tip-to-tip distance less than 1 to 2 prior austenite grains will coalesce, while those with distances greater than 2 to 3 prior austenite grains will change to stage II propagation. In the stage II regime, crack coalescence °ems after about 70% of the fatigue life Nf. 5. The lower the cycling frequency, the shorter will be the corrosion fatigue life. The combination of a high stress level and a low frequency can eliminate the in-air-fatigue micro structural barrier effect. 6. Cathodic polarisation (E=-1280mv (SCE)) can prevent the surface of the specimen from pitting, delay the stage I-to-stage II transition, and decelerate the early stage II crack growth rate. However, as a stage II crack grows, cathodic polarisation will accelerate the crack growth rate. 7. In a 0.6M NaC1 solution, the final stage I crack length increases from 50ium to 300 gm with increasing cyclic shear stress range (from 224 MPa to 926 MPa). This distance equals approximately 2 to 10 prior austenite grain diameters. The final stage I crack length is much longer under cathodic polarisation than for a free corrosion potential under the same stress range. There is no significant frequency effect on the final stage I crack length when the frequency is in the range of 2Hz to 12.51-1z. 8. The dislocation based Navarro-de los Rios model was employed in the present study to describe crack growth behaviour and to predict fatigue life. The pit growth behaviour, the crack transition from stage I-to-stage II, and a parabolic strain hardening law, were incorporated into the model to reflect more closely the actual fatigue behaviour of the material. The validity of the model was justified by the good agreement achieved between predictions based on the model and the experimental results.
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Saad, Sariffuddin Bin. "Finite element determination of the static strength of cracked tubular T-joints." Thesis, University of Nottingham, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.362919.
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Yoon, Se-Young. "Bonding Material Coated Clay for Improving Paper Properties." Diss., Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/14540.
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The paper industry utilizes fillers either to reduce the cost or to provide desired functional or end-use properties of paper products. However, there are disadvantages associated with higher filler loadings beyond a certain level, which reduces paper strength. The present study focused on improving the physical property of filled papers. Three methods of structuring fillers were designed; precipitation with starch, complexation with starch and fatty acid, and regeneration with cellulose. Because cellulose and starch have hydroxyl groups on the chemical structure, the hydrogen bonding between fillers and wood fibers is assumed to be occurred by structuring fillers.
For starch application, we used two different approaches; salt precipitation and fatty acid complexation. The cooked starch can be precipitated by certain salt solutions such as (NH4)2SO4. Also, the cooked starch can be complexed with fatty acid to produce an insoluble crystalline structure. When starch composites with clay made by both methods were put into the furnish as fillers, dramatic strength improvement was achieved such as 100-200% gains in tensile strength. This is due to the strong bonding between clay fillers and wood fibers, which is determined by Z-directional tensile strength. One of advantages is that using the starch-fatty acid complex has an inherent water repellent property, sizing effect.
For cellulose as a bonding material, N-methylmorpholine-N-oxide was used as a solvent to dissolve the cellulose. The advantage of using this method is that we can use the low grade cellulose. The physical properties of the cellulose coated clay handsheets were significantly improved, but optical properties such as brightness and opacity were inferior to the hadnsheets filled with starch-clay composites due to relatively large particle size.
In order to model the strength improvement by the composite filler, BDT theory, which is a modified Pages Equation, was used. After calculating the factors such as surface area and specific bond strength, the model matched well with the experimental results. Using this model, the tensile strength improvement could be predicted in terms of the change of bond strength and composite size.
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Collins, Travis Collins. "Estimating in-situ flexural strength of heat-affected prestressed concrete beams using constituent material models." Connect to this title online, 2008. http://etd.lib.clemson.edu/documents/1219953974/.
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Das, Shagata. "Performance Enhancement Of Controlled Low-Strength Grout Material (CLSM) For Annulus Voids Of Sliplined Culverts." University of Akron / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=akron162828626290938.
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Narayanaswamy, Nitin. "Adhesive modelling in multi-material structures : Evaluating the strength and fatigue life of adhesive joints." Thesis, Linköpings universitet, Mekanik och hållfasthetslära, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-165507.
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Advancements in material science and manufacturing techniques are enabling the use of lightweight metal alloys and polymer composites in several combinations and shapes for producing more efficient and lightweight structures for automotive applications without compromising strength, stiffness and/or durability. When evaluating the strength of the structure, the joints are of importance. For multi-material structures adhesives are often the best type of joints. However, traditional finite element methods using stress criteria cannot accurately predict the failure of these adhesive joints under static loading. In this thesis work a strength and fatigue model, formulated using energy release rate theory, is implemented in a post processing tool. Given a finite element model of an adhesive joint and a list of boundary elements and nodes this tool calculates the energy release rates in mode I and mode II, and if the fracture toughness of the adhesive is known, a prescribed mixed-mode failure index is calculated. To evaluate its predictions joint strength results are correlated to experiments. Specimens with combined shear and normal load forms the underlying experimental setup with change in strain rate and adhesive thickness as varying parameters. Methods for implementing the model for a car body structure with multiple adhesive joints is investigated, the tool proves to be scalable, however, the required finite element setup at the adhesive boundaries may not be present in a car body model and thus further work needs to carried out to accommodate irregularities like non-matching mesh in the car body finite element model. This model may be used for assessing the strength and durability of a car body structure comprising different materials joined together using adhesives.
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Laws, Paul. "Corrosion fatigue performance of welded high strength low alloy steels for use offshore." Thesis, Cranfield University, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.359541.
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Gingell, Andrew Donald Brian. "Corrosion fatigue crack growth and hydrogen embrittlement in high strength aluminium alloy 7150." Thesis, University of Cambridge, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.337942.
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Bryne, Lars Elof. "Time dependent material properties of shotcrete for hard rock tunnelling." Doctoral thesis, KTH, Betongbyggnad, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-145678.
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In this thesis different mechanical properties for shotcrete (sprayed concrete) such as compression strength, bond strength, bending tensile strength, elastic modulus, free and restrained shrinkage as a function of its age was investigated. One of the main issues was to investigate the difference between ordinary cast concrete and shotcrete. Reliable material data for young and hardening shotcrete is scarce which in the past have made such comparisons difficult. Also, less accurate data representative for cast concrete has often been used in numerical modelling and design analyses. The focus of the project has particularly been on the properties bond strength and restrained shrinkage for which two new testing methods has been developed and evaluated. Microstructural studies have also been performed as a complement to the bond strength testing. The bond to rock is one of the most important properties for shotcrete used as rock reinforcement. During the very first time after spraying the physical properties and the bond to the rock depend on the set accelerator and the micro structure that is formed. The investigation of early age bond strength of shotcrete is of great importance both from a production perspective and a safety perspective. The newly developed method was tested and evaluated and proved that it can be used for bond strength testing already from a couple of hours after shotcreting. The bond, or adhesion, depends on several factors such as texture of the rock, the type of accelerator, application technique, etc. In this work the development of the microstructure in the interfacial transition zone (ITZ) and strength of the bond was investigated. The results show that the bond strength is related to the hydration process, i.e. the strength gain of the shotcrete. The early development of the ITZ was here studied using a scanning electron microscope (SEM) making it possible to observe changes over time, before and after proper cement hydration. Restrained shrinkage cracking of shotcrete, especially in the case of shotcrete sprayed on soft drains that are parts of a tunnel lining not continuously bonded to the rock, can be detrimental for the sustainability of an infrastructure tunnel system. Maintenance and repair costs can be high over time. It is shown that the developed test method realistically captures the behaviour of shotcrete drains on hard rock in situ. The method can be used in the evaluation of different technical solutions for avoiding or minimizing shrinkage cracks in shotcreted soft drains. It can also be used to assess the performance of shotcrete fully bonded to a rock surface, with respect to the ability to prevent cracking or to distribute possible shrinkage damage into several fine cracks instead of one wide.QC 20140526
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Mostofa, Md Golam. "Base material characterisation of spoil piles at BMA coal mines." Thesis, Queensland University of Technology, 2015. https://eprints.qut.edu.au/90717/4/Md_Golam_Mostofa_Thesis.pdf.
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This project was an initiation to investigate slaking induced properties detrition of spoil pile materials with overburden pressure and time. The changes in the material properties over time are important parameters that control the behaviour and performance of the piles. The time dependent mechanical and hydraulic properties reported together with mineralogical changes. One chamber designed to apply slaking in the laboratory and geotechnical investigation conducted to fulfil the objective of this project.
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Jihan, Sha. "Studies of structure cracking and fracture strength of E-glass fibres using acoustic emission." Thesis, Robert Gordon University, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.294825.
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Liou, Wen-Jer, and 劉文哲. "Material Strength Evaluation System of Random Load." Thesis, 1995. http://ndltd.ncl.edu.tw/handle/04131693443711890380.
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Hsieh, Wei-Chi, and 謝偉祺. "Study of Controlled Low Strength Material Properties." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/18896924141635776660.
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碩士國立中興大學
土木工程學系所
98
For the pipeline backfill material, to improve the road using CLSM backfill quality of service, monitoring the Settlement amount of CLSM to compare the usefulness. CLSM is a material with high water-cement mixture, higher than normal concrete big settlement. CLSM settlement amount due on time has not been established, testing understanding in this experiment. The purpose of this study but to have different mixture CLSM, shrinkage and water cement ratio and loaded with or without compared to the settlement amount. Research the relationship between the mixture at the subsidence and construction quality. The results show that, the settlement amount will tend to gradually slow after 5 to 7 days, load carrying capacity of the CLSM in the settlement not much impact.
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Pun, Tin Ian, and 潘天恩. "Compressive Strength Experiment in Virtual Material Laboratory." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/90120238973667485738.
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碩士國立交通大學
土木工程系所
98
Abstract: With the constant progress of multimedia technology and network bandwidth, the traditional teaching environment that based on text and pictures will be integrated with media stream or virtual reality. Visual simulation boomed out to be an essential tool in the 21st century. Slowly, VR technology has been widely proposed as a major technological advance that has potential to support for education and most importantly, it allows students to visualize abstract concepts. This research mainly illustrates the study of virtual laboratory, the difference of teaching strategies to explore the changes of students’ concept understanding, learning motivation, computer learning motivation which influences their learning motivation and concept understanding. In this paper, the compressive strength experiment is one of the designed experiments. It integrates 3ds max, Auto CAD, Virtools to carry out a seemed-to-be-real 3D effect- Virtual Reality (VR). Through this event, students can “experience” the whole experiment procedures clearly without any space limit. Key word: Virtual Reality, Virtools, 3ds Max, Compressive Strength Experiment
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Vugampore, Jean-Marie Vianney. "Development of high strength material for smart aircraft bolt." Thesis, 2005. http://hdl.handle.net/10413/2835.
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Scientists are constantly seeking new and convenient non-destructive damage assessment techniques. In fact, a global market has developed for structural health monitoring products. Many of the currently available techniques are expensive and difficult to implement. An inexpensive alternative is technology based on strain memory alloys. These materials encompass a vast array of alloys, from austenitic stainless steels through to the extremely high strength TRIP steels. All, however, have in common the transformation from paramagnetic austenite to ferromagnetic martensite upon application of strain. The degree of ferromagnetism can be directly correlated to the peak strain undergone by the material. Strain memory alloys are not as expensive to manufacture as some smart materials, and in addition are capable of bearing significant load, and it is therefore possible to manufacture entire components from these alloys, thereby producing what is known as a smart component, i.e. one that is capable of doing the job of an ordinary component while at the same time assessing its own peak damage levels. A possible application of this technology is that of wing bolts for the Hercules e130 aircraft. The material usually used to manufacture the aircraft wing bolts is HSLA steel (AISI 4340). A strain memory alloy was therefore developed to match the mechanical properties of 4340 steel, while also having the requisite properties to perform the self damage-assessment. Ultra high strength TRIP steels were identified as possible candidates, and four alloys selected for investigation. These alloys were melted and then thermo-mechanically processed using a rolling operation. All alloys were tensile tested and magnetic susceptibility monitored. The final material selected possesses an ultimate tensile strength (UTS) of between 1270 and 1500 MPa with 10 to 12% elongation. The stress / strain induced transformation begins to occur before the yield point, which is important because bolts must be replaced before they fail. Compression tests were also performed, and yielded similar results to those of the tensile tests, with martensitic transformation again beginning before plastic yield. The strain induced phase transformation was confirmed not only by magnetic susceptibility measurements, but also by metallographic inspection before and after testing. A subscale Smart bolt was designed, manufactured and tested for magnetic sensitivity using a smart washer.Thesis (Ph.D.)-University of KwaZulu-Natal, 2005.
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Chen, Pen-Lin, and 陳本霖. "Reuse of Stone Sludge in Control Low Strength Material." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/rzjub5.
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碩士大漢技術學院
土木工程與環境資源管理研究所
102
ABSTRACT To achieve sustainable development, nations are actively transforming industrial waste into resources. In Taiwan, copious quantities of marble waste are produced annually. Recycling this waste into usable resources would reduce the amount of refuse and advance the goal of sustainable development. Accordingly, in this study, we explored the use of marble waste sludge in controlled low-strength material (CLSM) by replacing the fine aggregates in CLSM with an equal weight of marble waste. The pipe flow, chloride ion content, and compressive strength of nine CLSM mixtures were tested to examine the influence of marble waste sludge on CLSM characteristics. The results show that when 30%~90% (by weight) of the fine aggregates in CLSM were replaced with marble waste sludge, the CLSM pipe flow ranged between 20 cm and 22 cm, which complies with construction standards in Taiwan. Increasing the proportion of marble waste sludge decreased CLSM compressive strength. When 90% of fine aggregates were replaced with marble waste, the compressive strengths on Days 1 and 28 were 12 kgf/cm2 and 82 kgf/cm2, respectively, which conform to required specifications. However, the final setting time spans as much as 15 hours, which would require attention in practical applications. The chloride-ion content of CLSM substantially increased when cement accelerators were used; thus, the amount of cement accelerator used should not exceed 4% of cement weight. High proportions of marble waste resulted in decreased chloride-ion content in CLSM, but the amount of binder and coarse aggregates had limited effect on chloride-ion content.
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Liou, Jer-Yuan, and 劉哲元. "Study on Material Strength of FRP Wind Turbine Blades." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/55982974486122262940.
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碩士國立臺灣大學
工程科學及海洋工程學研究所
96
This study mainly focuses on the mechanical characteristic of glass fiber reinforced plastics (GFRP) used for wind turbine blades. According to the past investigation, we discuss the characteristic of the material, which is varying with the category of fiber and resin and the stacking sequence, applied on the different part of the blades. We processed the static test, including the tension, compression, and shear test, and dynamic test, mainly fatigue test, based on the standard of material test. Then the characteristic of GFRP is provided cleanly and the database is established to make the foundation of the study and numerical calculation. Meanwhile, we can discuss the failure form with the different stacking sequence and influence on the strength and stiffness of the different resin. This paper also applies the theoretical analysis to conduct the mechanical characteristic of material with the different stacking sequence. That is, we substitute the stiffness of the single axial laminates to determine the stiffness of the biaxial and triaxial laminates based on the compound rule for the composite material and then compare the results with the experimental results. Finally we use the finite element software, ABAQUS, to discuss the shear strength analysis of the GFRP laminated plate.
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張家瑋. "The Mechanical Behaviors of The Control Low Strength Material." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/02735203095812807028.
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碩士國立屏東科技大學
土木工程系碩士班
91
”Control Low Strength Material” is a self-compacted material. It is used primarily as a backfill material. This study investigate the mechanical behaviors of CLSM by experiment. The relationship is between the size of specimen and the uniaxial compressive strength are discussed first. Then the mechanical behaviors are investigated. The stress-strain curve of CLSM are obtained by the uniaxial compressive test. The elastic modulus is discussed by using the stress-strain curves. Two different mixtures Portland cement and Soil Amelioration are also used. The test results have been compared and discussed.