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Partington, Mark. "The effectiveness of polyacrylamide in providing short-term erosion control on steep slopes /." Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=80348.
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A study was conducted to determine if polyacrylamide (PAM) could be utilized as a best management practice to reduce soil erosion on forest road embankments. Experiments involving two different PAM application rates (10 and 20 kg/ha) were conducted using natural rainfall in 2001 and 2002 and indoor rainfall simulation. In 2001, PAM was combined with a broadcast application of grass seed.The study results suggest that PAM provided no statistically significant erosion control after natural rainfall on a loam soil. In the rainfall simulation experiments PAM applied at both 10 and 20 kg/ha significantly reduced soil erosion (by 75 and 77%) and the turbidity of runoff water (by 99%). PAM application at 10 kg/ha significantly increased grass densities (by 109%) compared with the control plots. However, PAM applied at 20 kg/ha provided no significant increase in grass density compared with the control.
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Weikle, Belinda M. "Preliminary investigation of energy dissipation at culvert outlets using a riprap step." Morgantown, W. Va. : [West Virginia University Libraries], 2000. http://etd.wvu.edu/templates/showETD.cfm?recnum=1280.
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Thesis (M.S.)--West Virginia University, 2000.Title from document title page. Document formatted into pages; contains ix, 168 p. : ill. (some col.) Vita. Includes abstract. Includes bibliographical references (p. 148-167).
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Mäkikyrö, M. (Marko). "Converting raw materials into the products–Road base material stabilized with slag-based binders." Doctoral thesis, University of Oulu, 2004. http://urn.fi/urn:isbn:9514272528.
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Abstract
A procedure is defined for commercializing slags arising as by-products of steelmaking, and this is used to develop certain products. The outcome of the present work comprised three products or groups of products: 1) slag-based binding agents, 2) a road structure improved by means of stabilization with such binding agents, and 3) a procedure for designing stabilized structures. The commercialization procedure was drawn up by examining the technical properties of the initial materials, excluding environmental acceptability and the mechanisms of their chemical reactions.
The research proceeded in stages, of which the first was a reconsideration of the results presented in the author's licentiate thesis concerning factors affecting the stabilization of road construction aggregates with blast-furnace slag-based binding agents and their significance. This was followed by a series of experiments designed to test the validity of these results. At the third stage the selection of slag-based binding agents was extended to include LD steel slag products, while the final stage consisted of the implementation of a set of test structures and associated preliminary experiments and monitoring measurements.
The binding properties of three blast-furnace slag products and three LD steel slag products, used separately or in various combinations, were examined in the course of this work, taking cement as a reference material. Materials were then eliminated as the research proceeded, either on account of their poor binding properties or on economic grounds. The final construction experiments were performed with three combinations: cement-activated granulated blast-furnace slag, LD steel slag-activated granulated blast-furnace slag and a mixture of ground granulated blast-furnace slag and cement.
The actual novel product among the slag-based binding agents to be introduced here is LD steel slag-activated granulated blast-furnace slag, which was found to be similar in its technical properties to cement-activated granulated blast-furnace slag. Structural layers stabilized with these two binding agents showed very similar bearing capacities, although the former did not reach the same compression strengths at an age of 91 days. The reasons for these similarities lay in a larger amount of binding agent used when activated with LD steel slag and the greater thickness of the stabilized layer, factors which both tended to compensate for the poorer compression strength.
The new information gained on the properties of cement-activated granulated blast-furnace slag and the mixture of ground granulated blast-furnace slag and cement opens up fresh opportunities for selecting binding agents and designing road structures. Formulae were developed here for predicting the uniaxial compression strength at 91 days, used as a stabilization criterion, from the value for a sample taken at 28 days, a technique which will speed up the assessment of stabilization results, especially when using slowly reacting slag-based binding agents.
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Zia, Seiar Ahmad. "The effect of different road load implementation strategies on fuel economy of USPS step vans." Morgantown, W. Va. : [West Virginia University Libraries], 2009. http://hdl.handle.net/10450/10375.
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Thesis (M.S.)--West Virginia University, 2009.Title from document title page. Document formatted into pages; contains xii, 92 p. : ill. (some col.), col. map. Includes abstract. Includes bibliographical references (p. 79-81).
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Knobel, Christian. "Optimal control allocation for road vehicle dynamics using wheel steer angles, brake, drive torques camber angles." Düsseldorf VDI-Verl, 2009. http://d-nb.info/992593425/04.
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Mendroková, Magda. "Most v obci Návsí přes řeku Olši." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2013. http://www.nusl.cz/ntk/nusl-226070.
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The diploma thesis deals with design and assessment of steel arched bridge with the semi through bridge deck placed on the third-class road. This steel structure is drawn up to bridge water barrier – the river Olše in Návsí. The distance between axes lay on abutments is 48,5 meters. The bridge´s supporting structure consists of two steel arches angled towards each other and fastened to the foundation blocks. The supporting beam of the bridge deck is tied to the arch by tie-rods. The tie-rods are designed to the V-shaped system.
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Winsteen, Albin Moran, and Haleh Nezamabadi. "One step further on the road to cultural diversity : - Implementing ethnic diversity among managers in Ericsson." Thesis, Stockholm University, School of Business, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-6455.
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The aim of this study is to find out what keeps the foreign workers in Ericsson from achieving leading roles in the organization. The low presentation of the immigrants in Ericsson’s management team compared to the proportion of immigrants in lower positions, suggests that there might be a glass ceiling in the organization. By examining the existing obstacles that non-Swedish employees at Ericsson face in getting into the management team, we can come up with solutions that can make it easier to overcome these barriers. In order to find out these difficulties, fourteen interviews have been conducted with four groups of respondents: Immigrant managers, Immigrant employees, Swedish managers and Swedish employees. The results of these qualitative interviews are then analyzed to reach to a conclusion and the possible solutions to resolve these difficulties. These different groups have given different perspectives in looking at this complex phenomenon. We asked about the factors that were assumed to be the main problems such as: society’s culture, deficiency in recognition of competence, lack of contact network, lack of communication skills, internal factors and finally the organizational factors. The results proved that all these factors can affect the possibilities for career advancement for immigrant employees in Ericsson in some degree, but the most visible factors were the culture, lack of contact network, and internal factors. Therefore the organization can resolve these difficulties by focusing on increasing diversity awareness and training, helping the foreign employees form contacts using various strategies.
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Bradley, David. "Occupational health and safety in the Scottish steel industry, c.1930-1988 : the road to 'its own wee empire'." Thesis, Glasgow Caledonian University, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.570877.
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Occupational health history is becoming an increasingly vibrant field of study, and this thesis will contribute to this subject by analysing one of the major industries in the twentieth-century Scottish economy. The history of the Scottish steel industry has been relatively neglected since its radical contraction in the 1980s and early 1990s, and this thesis adds to the attempts to address this. Utilising a number of sources, including trade union papers and oral testimony, this thesis engages with health and safety concepts pertaining to work in the steel industry. Significantly, it has been discovered that cultures of health and safety among workers were established relatively early on. It will be seen that the levels of commitment to industry-specific health and safety standards on the part of workers and trade unions, and employers and management, varied. This will then link in to the significance of government legislation in the 1970s. While employer initiatives of the privatised era were geared towards improving the workplace - such as the Craig War Memorial Home - they were highly localised in character. This lack of an 'across the board' experience therefore makes the health and safety legislation of the 1970s all the more significant. An attempt to assess the extent to which regulation of health and safety in the workplace had distinctively 'Scottish' features has also been made, and it will be seen that the locations of the Scottish plants and the changing nature of ownership of the industry had their own parts to play in the development of work culture. Moreover, it will be demonstrated that a stoic, fatalistic work culture was prevalent in the industry, and that a 'machismo' element was often absent. These themes, it will be seen, combined to create an atmosphere in which workers and, indeed, management - many of whom were drawn from local communities - were receptive to improvements in occupational health and safety practices. Despite varied experiences across plants and sectors of the steel industry, health and safety has become of increasing importance to the entirety of the workforce. The result of this is that procedures have developed from being left largely to 2 individual discretion, to the point where work in steel is dictated by the likely impact of tasks on oneself and others. It is now 'its own wee empire.' 3
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Kuthy-Saenger, Juan Arturo. "Comparison study of the savings between a single and a double step toll systems." Morgantown, W. Va. : [West Virginia University Libraries], 2001. http://etd.wvu.edu/templates/showETD.cfm?recnum=1899.
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Thesis (M.S.)--West Virginia University, 2001.Title from document title page. Document formatted into pages; contains x, 48 p. : ill. Vita. Includes abstract. Includes bibliographical references (p. 41-42).
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Campbell, Peter Cameron. "Application of microstructural engineering to the controlled cooling of steel wire rod." Thesis, University of British Columbia, 1989. http://hdl.handle.net/2429/29065.
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The concept of microstractural engineering has been applied to Stelmor cooling of steel wire rod. The Stelmor process is situated immediately following the rod mill and utilizes forced air to cool steel rod from the rolling temperature, through austenite transformation, down to a temperature suitable for handling. A mathematical model has been developed for the prediction of the mechanical properties of the steel rod as a function of cooling parameters in the process and steel composition. The model is based on one-dimensional heat conduction within the rod and is limited to plain-carbon eutectoid and hypoeutectoid steels. Phase transformation kinetics in the model, for both the austenite-ferrite and austenite-pearlite reactions, have been characterized through the use of the Avrami equation. A combination of experimental and literature data have been employed for the development of equations to quantitatively predict the microstructure formed in the steel rod after transformation. A modified Gladman equation was adopted for the strength predictions.
Validation of the model has been achieved with controlled cooling experiments conducted in the laboratory. The experiments were designed to simulate the Stelmor process, involving a range of steel grades, rod diameters and air velocities. Thermal histories in steel rod samples during forced air cooling were acquired by mounting a thermocouple at the centreline of each rod. After cooling, the rod samples were subjected to microstructural examination and mechanical testing. Results from this investigation were utilized to develop relationships among steel composition, thermal history and ferrite fraction, ferrite grain diameter and pearlite interlamellar spacing. The laboratory data was also utilized to modify the strength predictions of the Gladman equation.
In order to obtain information on cooling conditions in an industrial setting, a series of experiments has been conducted on an operating Stelmor line at the No. 2 Rod Mill of Stelco Hilton Works. The technique followed in the plant trials was similar to that employed in the laboratory and the thermal histories of the test rods allowed the mathematical model to be "tuned" to operating conditions. Mechanical properties for several industrial steel grades were also measured during the plant trials, and have been applied to test the predictive capability of the model.
Comparisons of the model-predicted thermal histories, microstructures and mechanical properties with those measured in both the laboratory and plant tests have been made. The results of the thermal history comparison for both laboratory and plant conditions showed good agreement between the model-predicted and measured centreline temperatures of control-cooled steel rod. Predicted temperatures during the austenite-ferrite and austenite-pearlite phase transformations were within the expected error associated with prediction of transformation kinetics. Good agreement was obtained between model-predicted and measured ferrite fraction, ferrite grain diameter and interlamellar pearlite spacing. Yield strengths and ultimate tensile strengths predicted by the model for the laboratory and plant tests displayed excellent agreement with measured strengths.
In order to obtain a test of the predictive capability of the model under Stelmor line conditions, an independent set of ultimate tensile strengths for Stelmor-cooled steel grades was obtained. These samples were taken directly from grades being processed on the line. A comparison between model-predicted and measured UTS for these grades yielded excellent agreement in the 1020-1040 and eutectoid composition range, with a fair prediction obtained for 1055-1065 grades.Applied Science, Faculty of
Materials Engineering, Department of
Graduate
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Gillström, Peter. "Alternatives to pickling; preparation of carbon and low alloyed steel wire rod /." Örebro : Örebro universitetsbibliotek, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-376.
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Morales, Franklin R. "Magnesium and calcium rod injection for desulphurization of steel and hot metal." Thesis, McGill University, 1988. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=61923.
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Correard, Gilvan Cesar de Castro [UNESP]. "Projeto de uma roda para comporta vagão usando elementos finitos." Universidade Estadual Paulista (UNESP), 2006. http://hdl.handle.net/11449/97100.
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O objetivo desta pesquisa foi apresentar um método de análise para a solução de problemas de contato por elementos finitos e o cálculo dos componentes mecânicos que fazem parte do projeto de uma roda de aço. Foi demonstrado passo a passo à execução de um cálculo analítico da roda de uma Comporta Vagão, calculando as cargas radial e axial presentes, verificando a tensão de Hertz, as tensões localizadas no cubo da roda, as tensões atuantes no eixo e a seleção do rolamento. Após esta etapa retiraram-se os parâmetros iniciais que foram utilizados no cálculo analítico para buscar o cálculo por elementos finitos. Assim, foram definidas as superfícies de contato, a geometria dos componentes, a malha, as restrições, as condições de contorno e por fim a análise dos resultados encontrados antes e após o projeto. Dessa maneira, podê-se determinar com precisão os pontos de concentração de tensão para eliminação as falhas. Com a busca deste cálculo, usando a análise por Elementos Finitos, respaldado pelo cálculo analítico, foi possível reduzir o diâmetro da roda para obter ganhos em massa para este tipo de equipamento que usa uma quantidade alta de rodas (acima de 100 rodas), sem alteração da confiabilidade das peças durante seu funcionamento.
The objective of this research was to present an analysis method for the solution of contact problems for finite elements and the calculation of the mechanical components that are part of the project of a steel wheel. It was demonstrated step by step the execution of an analytic calculation of the wheel of a Fixed Wheel Gate, calculating the radial and axial loads present, verifying the Hertz pressure, the concentrated stresses in the hub of the wheel, the acting stresses in the shaft and hub, and the selection of the roller bearings. After this stage the initial parameters were used in the analytic calculation in order to obtain the calculation using finite elements. After this, it was defined the contact surfaces, the geometry of the components, the mesh, the restrictions, the real constraints and finally the analysis of the results found before and after the project. After this calculation, the other analysis was established in order to determine the points of concentration stress accurately for the elimination of fails. In order to obtain the calculation, using Finite Elements, by the analytic calculation it was possible to reduce the diameter of the wheel to obtain earn in mass for this type of equipment that uses a high amount of wheels (above 100 wheels), without alteration of the reliability of the parts during the operation.
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Correard, Gilvan Cesar de Castro. "Projeto de uma roda para comporta vagão usando elementos finitos /." Guaratinguetá : [s.n.], 2006. http://hdl.handle.net/11449/97100.
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Orientador: Fernando de Azevedo SilvaBanca: João Zangrandi Filho
Banca: Anselmo Monteiro Ilkiu
Resumo: O objetivo desta pesquisa foi apresentar um método de análise para a solução de problemas de contato por elementos finitos e o cálculo dos componentes mecânicos que fazem parte do projeto de uma roda de aço. Foi demonstrado passo a passo à execução de um cálculo analítico da roda de uma Comporta Vagão, calculando as cargas radial e axial presentes, verificando a tensão de Hertz, as tensões localizadas no cubo da roda, as tensões atuantes no eixo e a seleção do rolamento. Após esta etapa retiraram-se os parâmetros iniciais que foram utilizados no cálculo analítico para buscar o cálculo por elementos finitos. Assim, foram definidas as superfícies de contato, a geometria dos componentes, a malha, as restrições, as condições de contorno e por fim a análise dos resultados encontrados antes e após o projeto. Dessa maneira, podê-se determinar com precisão os pontos de concentração de tensão para eliminação as falhas. Com a busca deste cálculo, usando a análise por Elementos Finitos, respaldado pelo cálculo analítico, foi possível reduzir o diâmetro da roda para obter ganhos em massa para este tipo de equipamento que usa uma quantidade alta de rodas (acima de 100 rodas), sem alteração da confiabilidade das peças durante seu funcionamento.
Abstract: The objective of this research was to present an analysis method for the solution of contact problems for finite elements and the calculation of the mechanical components that are part of the project of a steel wheel. It was demonstrated step by step the execution of an analytic calculation of the wheel of a Fixed Wheel Gate, calculating the radial and axial loads present, verifying the Hertz pressure, the concentrated stresses in the hub of the wheel, the acting stresses in the shaft and hub, and the selection of the roller bearings. After this stage the initial parameters were used in the analytic calculation in order to obtain the calculation using finite elements. After this, it was defined the contact surfaces, the geometry of the components, the mesh, the restrictions, the real constraints and finally the analysis of the results found before and after the project. After this calculation, the other analysis was established in order to determine the points of concentration stress accurately for the elimination of fails. In order to obtain the calculation, using Finite Elements, by the analytic calculation it was possible to reduce the diameter of the wheel to obtain earn in mass for this type of equipment that uses a high amount of wheels (above 100 wheels), without alteration of the reliability of the parts during the operation.
Mestre
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Dixon, Teresa Joan. "The effect of microstructure in the advances of hot rolling of steel." Thesis, University of Sheffield, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.286885.
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Walawender, Kinga Roksana. "Context Sensitive Solutions for Road Infrastructures: Design of a Wildlife Crossing over the S11 Motorway in Poland." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018.
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Wildlife crossings are present as a part of infrastructure systems since the 1950’s. Their development through years has proven that they are an integral part when considering building highways all over the world.
This paper is aimed to bring closer to a broader public the potential of wildlife crossings while also highlighting their importance. What is more an exemplary overpass over the
S11 motorway in Poland has been designed following given recommendations and studying errors on already existing ones.
Wildlife crossings divide into three main categories: overpasses, underpasses, and crossings over the road. The latter gives the worst results as to mortality rate which indicates the necessity to upgrade crossings over the road to ones minimalizing possibility of accidents. What is more, a social campaign should be started to explain briefly but firmly why do we even need animal crossings as there are many misconceptions regarding this subject.
New visions and ideas focus mainly on integrity and aesthetics, as construction is already developed on a high note. Engineers should work closely with ecologists to ensure proper migration patterns and provide a continuation to migration corridors.
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Fahd, Faisal. "Risk Assessment Approach for Evaluating Recycled Materials Use in Road Construction: A Pilot Study." University of Toledo / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1230027556.
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Nickoletopoulos, Nicholas. "Physical and numerical modeling of steel wire rod fracture during upsetting for cold heading operations." Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=37796.
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A comprehensive methodology to physically and numerically model upsetting in cold heading was developed.The physical model was a Drop Weight Test with a guided pocket-die set capable of approximating industrial cold heading conditions. The results show that the test is sensitive to the critical parameters for cold heading. These include surface quality, residual element level, nitrogen content, microstructure, decarburization, and specimen geometry. The test is capable of assessing the fracture behavior of cold heading materials.
One goal of the study was to reveal differences in fracture behavior with varying steel sources. Accordingly, the matrix of test materials consisted of grade 1038 steels from three different steel sources.
Material preparation and conditioning of test materials approximated industrial procedures for cold heading materials. These procedures included hot rolling, controlled rod cooling, descaling, straightening, lime coating and lubricating, and wire drawing. Spheroidization of test specimens was performed in an industrial batch furnace using an industrial heat treatment cycle.
A finite element program (FEM) enabled the simulation of upsetting in cold heading. The inputs required to model the cold heading process include flow stress behavior and friction conditions representative of cold heading. These inputs were obtained using the CANMET Cam Plastometer and the Friction Ring Test.
The Cockcroft and Latham fracture constants for an as-rolled and a spheroidize annealed 1038 material were computed by FEM modeling and the critical values were calibrated using the Drop Weight Test. The fracture criterion constant was found to be independent of strain path for upsetting in cold heading and thus is material-related.
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Eklund, Gustav. "Experimental and Numerical Investigation of Ratcheting Effects in 316L Stainless Steel - The Two-Rod approach." Thesis, KTH, Hållfasthetslära (Inst.), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-178802.
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This Master’s Thesis was conducted during spring 2014. An experimental and numerical investigation was conducted on the austenitic 316L stainless steel. The main focus of the study was the investigation of ratcheting effects. Experimentally, the main focus was the two-rod test, which had not been conducted previously. The two-rod test resembles a structure and a load case where ratcheting effects may be produced, although being less complicated than structures used in prior studies. Furthermore, the stress state in the structure is uniaxial. Other tests were also performed to characterize the material. Based on results from uniaxial tensile tests and fully reversed strain cycling of 316L, four material models were calibrated. The four material models were Bi-linear kinematic hardening model Multilinear kinematic hardening model (Mróz) Armstrong-Frederick non-linear kinematic hardening model Chaboche non-linear kinematic hardening model with three superimposed back-stress tensors. The two-rod test was then numerically simulated with different material models. The results from the FE simulations were then compared to the test results obtained from the two-rod tests. The goal, apart from investigating the ratcheting effects in 316L steel, was to evaluate the material models’ ability to reproduce the two-rod test results. The results from the comparison suggest that the bi-linear and the multilinear material model agreed with the test results to a larger extent than the Armstrong-Frederick and Chaboche model. The two non-linear hardening material models predicted in most cases a constant ratcheting rate which did not agree with the test results. Even though the predictions of the two-rod tests with the bilinear and the multilinear models generally was better than predictions with the two non-linear hardening material models, the bilinear and the multilinear models predicted plastic shakedown in certain cases which was not observed in the tests. The employment of an isotropic part in the non-linear kinematic hardening material models might have improved the simulations’ agreement to experimental results. The setup for the two-rod test proved robust and reliable. The results suggest that structural ratcheting effects dominate the two-rod test results. Furthermore, the comparison between simulations and the two-rod tests suggest that a more advanced material model does not necessarily yield in a better prediction.Det här examensarbetet utfördes under våren 2014. En experimentell och numerisk undersökning genomfördes på det austenitiska rostfria stålet 316L. Huvudområdet för studien var att undersöka fenomenet ratcheting (progressiv plastisk deformation). Experimentellt var huvudfokus på det så kallade tvåstångstestet, vilket tidigare inte hade utförts. Tvåstångstestet utgör en struktur och ett lastfall vari ratcheting kan skapas, samtidigt som strukturen är mer renodlad än de som undersökts i tidigare studier för samma ändamål. Dessutom är spänningstillståndet enaxligt i strukturen. Utöver tvåstångsprovning gjordes även ytterligare provning för att karaktärisera materialet. Utgående från resultat från enaxligt dragprov och fullt reverserad töjningsstyrd cykling anpassades fyra materialmodeller efter materialet. Dessa fyra materialmodeller var Bi-linjär kinematiskt hårdnande modell Multilinjär kinematiskt hårdnande modell (Mróz) Armstrong-Frederick icke-linjärt kinematiskt hårdnande modell Chaboche icke-linjärt kinematiskt hårdnande modell med tre superponerade back stress- tensorer. En FEM-modell över tvåstångsprovet användes för att simulera de olika materialmodellernas respons. Resultaten från dessa jämfördes sedan med resultaten från tvåstångsprovningen. Målet, bortsett från att karaktärisera ratchetingeffekterna i 316L-stålet, var att utvärdera materialmodellernas förmåga att återskapa resultaten från tvåstångsprovningen. Resultaten från jämförelsen mellan simuleringarna och tvåstångsprovningen pekar på att den bi-linjära och den multilinjära materialmodellen förmår återskapa provresultaten bättre än Armstrong-Frederick-modellen och Chaboche-modellen. De två sistnämnda materialmodellerna predikterade i de flesta fall konstant ratchetinghastighet, vilket inte överensstämde med provresultaten från tvåstångsprovningen. Även om predikteringen av tvåstångsprovningen med den bi-linjära och multilinjära materialmodellen överlag var bättre än för de icke-linjärt hårdnande materialmodellerna predikterade den bi-linjära och multilinjära materialmodellen i vissa fall plastisk shakedown, vilket inte sågs i provresultaten. Införandet av isotropt hårdnande i de icke-linjärt kinematiskt hårdnande materialmodellerna kan ha förbättrat simuleringarnas överensstämmande med provresultaten då materialet visar på omfattande plastiskt hårdnande, både i monotont dragprov såväl som cykliskt hårdnande. Metoden som utvecklades för tvåstångsprovningen visade sig robust och pålitlig. En slutsats som kan dras är att effekter från materialratcheting förmodligen är små i jämförelse med effekter från strukturratcheting i tvåstångsprovningen. Dessutom kan från jämförelsen mellan simuleringarna och tvåstångsprovningen sägas att en mer avancerad materialmodell inte nödvändigtvis resulterar i en prediktering som överensstämmer bättre med provningen.
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Yoshimura, Koji. "Robust Design of Roll Pass for Reduced Geometric Variance in Hot Rolling of Steel Rod." The Ohio State University, 1995. http://rave.ohiolink.edu/etdc/view?acc_num=osu1380554061.
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Mooney, Dennis Todd 1964. "Experimental and numerical study of the rod shear test for determining steel-sand interface behavior." Diss., The University of Arizona, 1998. http://hdl.handle.net/10150/282785.
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One laboratory technique to determine the unit side resistance of piles is the rod shear test. In a rod shear test a model pile is placed inside a cylindrical soil specimen. A confining pressure is then placed around the specimen/pile assembly and the model pile axially loaded. In some cases rod shear tests in sands have produced anomalously high interface friction angles (δ) which may be, at least in part, due to differences in how the normal stress on the model pile has been interpreted. Therefore, the usefulness of the rod shear test as a means to determine interface behavior for pile design is questionable. In this study, a new rod shear device was constructed to determine the behavior of steel-sand interfaces, and a numerical model was used to further evaluate the results. The interfaces tested were smooth and rough model piles in dense and loose sand. Results for the smooth pile tests are consistent with published values. However, tests with the dense and loose sands using rough piles produced interface friction values that were, in some instances, higher than the dilatant friction angle (φ(d)) for the sand at comparable stress levels. Elastic and elasto-plastic (modified Cam-clay) models failed to predict the high interface friction angles. Therefore it is suggested that the rod shear test imposes heretofore unrecognized kinematic restraints to volume change that, coupled with the discrete nature of the sand, lead to the development of a complex arching system The result is that effective normal stress on the pile is increased beyond the applied confining pressure. Evidence for such behavior included the observation of secondary features in the dense sand following pile displacement, the existence of force chains and work with discrete element systems showing that stress distribution in dense arrays is nonuniform.
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Vlček, Radek. "Ocelová konstrukce mostu na pozemní komunikaci." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2016. http://www.nusl.cz/ntk/nusl-240323.
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The content of the thesis is a proposal of steel load-bearing structure (carrying structure of a steel) bridge of the span of 31+74+31m with the bottom bridge deck taking over the second-class road in the territory of Olomouc city. The bridge deck is created by composite steel-concrete slab with crossbars. The solution was focused on using arched construction in the middle of the bridge with different tilt of arches to the horizontal central axis of the bridge. Under the term of the solution four alternatives have been calculated. The most optimal solution was selected and processed in detail. The calculations were made in compliance with the Czech technical norms ČSN EN.
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Mirjana, Filipovic. "Evolution of artificial defects during shape rolling." Licentiate thesis, Högskolan Dalarna, Materialvetenskap, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:du-5215.
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Very often defects are present in rolled products. For wire rods, defects are very deleterious since the wire rods are generally used directly in various applications. For this reason, the market nowadays requires wire rods to be completely defect-free. Any wire with defects must be rejected as scrap which is very costly for the production mill. Thus, it is very important to study the formation and evolution of defects during wire rod rolling in order to better understand and minimize the problem, at the same time improving quality of the wire rods and reducing production costs. The present work is focused on the evolution of artificial defects during rolling. Longitudinal surface defects are studied during shape rolling of an AISI M2 high speed steel and a longitudinal central inner defect is studied in an AISI 304L austenitic stainless steel during ultra-high-speed wire rod rolling. Experimental studies are carried out by rolling short rods prepared with arteficial defects. The evolution of the defects is characterised and compared to numerical analyses. The comparison shows that surface defects generally reduce quicker in the experiments than predicted by the simulations whereas a good agreement is generally obtained for the central defect.
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Šťastná, Barbora. "Vliv silničních záchytných systémů na počet a druh dopravních nehod." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2013. http://www.nusl.cz/ntk/nusl-225924.
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The aim of the master´s thesis is to analyze the types of road restraint systems, a description of testing road restraint systems and the use of wire rope safety fence in the Czech Republic and abroad. In addition, there is an analysis on the highway of R48 in the section Nový Jičín – Příbor and assessed in terms of the number and type of accidents in connection with wire rope safety fence.
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Camp, Joe Harden. "Birch rod to arsenal : a study of the Naval Ordnance Plant at South Charleston, West Virginia and the search for a government industrial policy /." VIEW WEB VERSION, 2002. http://etd.wvu.edu/templates/showETD.cfm?recnum=2359.
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Filipovic, Mirjana. "Evolution of artificial defects during shape rolling." Licentiate thesis, Stockholm : Division of Mechanical Metallurgy, Department of Material Science and Engineering, Industrial Engineering and Management, Royal Institute of Technology, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4350.
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Biswas, Souvik. "Simulation of thermo-mechanical deformation in high speed rolling of long steel products." Link to electronic thesis, 2003. http://www.wpi.edu/Pubs/ETD/Available/etd-1027103-203032/.
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Thesis (M.S.)--Worcester Polytechnic Institute.Keywords: product geometry; hot rolling; high speed rolling; rolling simulation; bar and rod rolling; free surface; finite element analysis. Includes bibliographical references (p. 69-75).
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Vošček, Martin. "Silniční a tramvajový most." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2017. http://www.nusl.cz/ntk/nusl-265573.
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The subject of this Diploma Thesis is to develop different alternatives of the road and tram bridge. It is a river bridge with the length of 52,5 m. There are compared two proposals, while in the first proposal it is an arch bridge with the tension bars. The second proposal which is also finalized as the winning proposal is the truss structure. Both proposals have composite deck. The structure is designed from steel S355 and concrete C35/45. The load bearing structure is designed in accordance with applicable technical standards.
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Kloda, Petr. "Ocelová konstrukce silničního mostu." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2019. http://www.nusl.cz/ntk/nusl-391963.
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The aim of the master thesis was a design of the steel-concrete composite road bridge for a main road in Ostrava. The part of the design was a variant design of the bridge which has theoretical spans equal to 44 m + 55 m + 44 m. Total span of the bridge is then 143 m. Two variants of the bearing steel structure are compared in the preliminary structural design, in the first one a twin-girder is designed and in the second one a box-girder bridge is assessed. The width of the bridge is 14 m and a launching of the bridge without temporary supports is chosen as the assembly method. The design of the bridge structure was carried out according to the valid standard ČSN EN. The final thesis contains variant design, structural design report, where a bill of quantities is stated, engineering report and drawings.
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Bergstedt, Pontus, and Viktor Svemark. "Konstruktion av stegmatare för vevstakar." Thesis, Högskolan i Skövde, Institutionen för ingenjörsvetenskap, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-17369.
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Detta arbete beskriver förarbete och konstruktion av en stegmatare som sorterar och orienterar vevstakar för en takttid på tio sekunder. Industrier är ofta beroende av materialhanteringsutrustning där olika processer säkerställer någon form av sortering eller orientering, vilket styrker arbetets relevans. Detta har skett genom att dela in maskinen i två huvudfunktioner; trappfunktionen, som försorterar och transporterar vevstakarna vidare till andra huvudfunktionen; orienteringsfunktionen, där orienteringen sker. Genom att tillämpa metoder inom; konstruktion & tillverkning, feleffektsanalys och programvaror för materialdatabashantering, datastödd design, samt numerisk hållfasthetsanalys kunde en konstruktion utformas som speglar de aspekter som kännetecknar en genomtänkt produkt. Sju olika designmetoder användes för att generera och utvärdera idéer i flera itererande steg. Tio undersökande experiment utfördes som ytterligare utvärdering av koncept samt underlag för vidare beräkningar och slutsatser. Utformningen av stegmataren resulterade i en enkelverkande lutande trapp med två rörliga trappsteg och ett statiskt mellan dem för överföring. En enkelmatning efter trappen i form av ett “skovelhjul” säkerställer att vevstakarna levereras en-och-en till orienteringsfunktionen samtidigt som den garanterar takttiden. En orienteringsfunktion bestående av ett “rullband” som med hjälp av friktion och tyngdpunktsförskjutning orienterar vevstakarna med vevänden först. Slutligen studerades tre kritiska områden i konstruktionen för vidare analys med finita element-metoden med godkända resultat. Samtliga mål för projektet uppnåddes, exempelvis har stegmataren färre unika komponenter än befintliga lösningar. Ambitionen var att utforma stegmataren med en låg grad av komplexitet och utan sensorer har genomsyrat hela projektet, vilket även har uppnåtts.This work describes the preparatory work and construction of a step feeder that sorts and orients connecting rods in a cycle time of ten seconds. Industries are often dependent of different material handling operations which assures a specific material orientation, which validates the importance of this work. This has been done by dividing the machine into two main functions; Stair case-function, which pre-sorts and transports the connecting rods further to the second function, the orientation- function where the orientation is performed. By using methods such as; design for manufacture & assembly, failure mode & effects analysis and softwares for material database handling, computer aided design and numerical strength analysis a construction could be formulated which reflects the aspects that characterize a well-planned product. Seven different design-methods were used in order to generate and evaluate ideas in several iterated steps. Ten investigative experiments were conducted as an additional evaluation of concepts and as a basis for further calculations and conclusions. The formulation of the step feeder resulted in a single-acting stair with two moving stairs and a static between them for transfer. A single-feeder after the staircase in the shape of a “paddle wheel” ensures that the connection rods are delivered one-by-one to the orientation-function while also ensuring the cycle time. An orientation-function consisting of a “conveyor“ that with the aid of friction and an offset of the center of gravity orients the connecting rods with the crankshaft-end first. Lastly were three critical areas in the construction further examined with finite element method with passing results. All objectives for the project were achieved, the step feeder have for instance fewer unique components than existing solutions. The ambition was to design the step feeder with a low grade of complexity and without sensors have permeated throughout the entire project, which also was achieved.
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Kuba, Michal. "Návrh silničního ocelobetonového komorového mostu na obchvatu Bludova." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2018. http://www.nusl.cz/ntk/nusl-372194.
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The aim of this work is design and assessment of the box-girder road bridge on by-road of Bludov. Bridge is designed as composite steel concrete bridge with 5 spans with distances between supports of 31,25 m; 40,0 m; 60,0 m; 60,0 m and 40,35 m. Main bearing structure is designed as open steel box-girder with reinforced concrete deck. Box girder is braced with longitudinal and transversal bracings. Main structure is separated for each traffic direction. The bridge crosses river Morava and railway in 2nd and 3rd span, respectively. The category of road I/44 is S 21,5/100. The height of steel box girder is designed as 2,5 m. Bridge will be built by incremental launching method, with in-situ casted concrete deck afterwards. The bridge is designed according to current standards. Supporting elements are designed from steel of class S 355 and concrete of class C35/45.
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Silva, Irwing Aguiar Ribeiro da. "Modelagem do comportamento dinâmico e análise de fadiga de pontes rodoviárias mistas (aço-concreto)." Universidade do Estado do Rio de Janeiro, 2014. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=9076.
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Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorConsiderando-se os diversos carregamentos que solicitam a estrutura de uma ponte rodoviária, ao longo de sua vida útil, alguns possuem um comportamento essencialmente dinâmico, ou seja, variam com o tempo, diferentemente do que é considerado na prática corrente de projeto desse tipo de obra de arte. Em geral, os projetistas desse tipo de estrutura têm tratado carregamentos como o de vento, tráfego de veículos e de pedestres como ações de natureza estática, ignorando seu perfil cíclico. Tal consideração, em diversas situações de projeto, tende a minorar os efeitos das ações dinâmicas sobre o sistema estrutural. Além disso, estruturas submetidas a solicitações cíclicas, sob uma carga inferior à caga máxima suportada pelo material, estão sujeitas ao fenômeno da fadiga. A consideração adequada de todos estes aspectos mostra-se fundamentalmente importante para correta avaliação dos níveis de esforços solicitantes do sistema estrutural e, bem como, para a identificação de fenômenos importantes como o da fadiga que pode vir a provocar, por exemplo, a ruptura de componentes estruturais sem aviso prévio ou motivo aparente. Para tal, nesta dissertação as técnicas para a contagem de ciclos de tensão e a aplicação das regras de dano acumulado foram analisadas através de curvas do tipo S-N, associadas a diversas normas de projeto. A ponte rodoviária mista (aço-concreto) investigada neste estudo é constituída por seis vigas de aço longitudinais com enrijecedores transversais, oito transversinas e por um tabuleiro de concreto armado. O modelo numérico-computacional, desenvolvido para a análise dinâmica da ponte, foi elaborado com base em técnicas usuais de discretização através do método dos elementos finitos. As mesas e almas das vigas, assim como os enrijecedores , foram modelados por elementos de casca e laje de concreto armado, por elementos sólidos. O carregamento dinâmico avaliado no presente estudo diz respeito ao tráfego de veículos, cuja representação se dá a partir de sistemas "massa-mola-amortecedor". Os comboios formados são adotados como sendo semi-infinitos, deslocando-se com velocidade constante sobre a ponte. As conclusões da presente investigação versam acerca da vida útil de serviço dos elementos estruturais de pontes mistas (aço-concreto).
Considering the various shipments requesting the structure of a road bridge over its useful life, some are of an essentially dynamic behavior, ie , vary with time, contrary to what is considered standard practice in the design of this type of work of art. In general, the designers of this type of structure have treated loads such as wind, vehicles and pedestrians as traffic static nature of actions, ignoring their cyclical profile. This consideration, in various design situations, tends to mitigate the effects of dynamic actions on the structural system. Furthermore, structures subjected to cyclic requests under a lower load at maximum shits supported by the material, are subject to fatigue phenomenon. The proper consideration of these aspects is shown fundamentally important for accurate assessment of levels of internal forces in the structural system, as well as for the identification of important phenomena such as fatigue which may ultimately lead, for example, disruption of structural components without warning or apparent reason. To this end, this dissertation techniques for counting cycles of tension and enforcement of accumulated damage were analyzed by the type SN curves associated with various design standards. Mixed road bridge (steel-concrete) investigated in this study consists of six longitudinal steel girders with transverse stiffeners eight crossbeams and a deck of reinforced concrete. The numerical - computational model developed for the dynamic analysis of the bridge, was based on standard techniques of discretization by finite element method. The tables and souls of the beams, as well as the stiffeners were modeled by shell elements and reinforced concrete slab, for solid elements. The dynamic loading evaluated in this study relates to vehicular traffic, whose representation is given from "mass - spring - damper systems." Trains formed are adopted as semi - infinite, moving with constant speed on the bridge. The findings of this research Versam about the service life of the structural elements of composite (steel-concrete) bridges.
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Hollý, Tomáš. "SO 217 Most přes řeku Morávku v km 6.205." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2012. http://www.nusl.cz/ntk/nusl-225523.
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The subject of the thesis is to design and consider steel superstructure of a composite steel-concrete road bridge. It is a continuous beam with seven spans of 36,0 + 57,0 + 75,0 + 90,0 + 75,0 + 57,0 + 36,0 = 426 meters. The superstructure consists of welded I-beams, which pass into closed box girder. The calculations take into account the construction phase.
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Westin, Tommy. "Induktiv provning av ferritiskt rostfritt stå." Thesis, Högskolan Dalarna, Materialvetenskap, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:du-10039.
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The report examines the factors which may be a contributing cause to the problems that are present when ferritic stainless steel are eddy current tested in a warm condition. The work is carried out at Fagersta Stainless AB in Fagersta which manufactures stainless steel wire. In the rolling mill there is an eddy current equipment for detection of surface defects on the wire. The ferritic stainless steels cause a noise when testing and this noise complicates the detection of defects.Because of this, a study was made of how the noise related to factors such as steel grade, temperature, size and velocity. By observing the signal and with the possibilities to change the equipment settings the capability to let a signal filter reduce the noise level were evaluated. Theories about the material's physical properties have also been included, mainly the magnetic properties, electrical conductivity and the material's tendency to oxidize.Results from the tests show that a number of factors do not affect the inductive test significantly and to use a filter to reduce the noise level does not seem to be a viable option. The level of noise does not relate to the presence of superficial particles in form of oxides.The ferritic stainless steels showed some difference in noise level. Which noise level there was did match well with the steels probability for a precipitation of a second phase, and precipitation of austenite may in this case contribute to noise when using an eddy current instrument.The noise is probably due to some physical material property that varies within the thread.
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Černoch, Jakub. "Lávka pro pěší." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2017. http://www.nusl.cz/ntk/nusl-265478.
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Master´s thesis deals with design and complex static assessment of steel and timber cable stayed footbridge structural system over the water area. The footbridge is situated into the area of Podyjí National Park near the city of Hnanice. Footbridge span is being used as 52 metres. The structure is formed by flat arched main beams, floor beams, crossbeams, under-deck bracing, pylons and rods. From two variations of footbridge, one was selected and elaborated in more details.
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Kábrt, Michal. "Ocelová rozhledna." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2018. http://www.nusl.cz/ntk/nusl-372095.
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The aim of the diploma thesis was to make a structural design of steel-load-carrying structure of steel lookout tower, in the grounds of domestic brewery in Humpolec. Lookout tower will be part of newly built centre for customers of the brewery. The layout and shape of the load-carrying structure of steel lookout tower follow the brewery chimney with height of 32.7 m with circular ground plan and outside diameter of 3.5 m in the heel and 2.3 m at the top. The chimney is independent of the construction of the lookout tower. The ground plan and dimensions of the lookout tower were considered taking into account the required spacing of the structure from adjacent buildings and ensuring sufficient dimensions for the required passage between the future lookout tower and the existing building of the boiler room. RFEM was used for calculation internal forces and assessment on individual structural elements, according to the valid Eurocodes.
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Uhl, Milan. "Návrh silničního spřaženého mostu na obchvatu Bytomi." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2016. http://www.nusl.cz/ntk/nusl-240415.
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Bílek, Tomáš. "Vícepodlažní administrativní budova ve Zlíně." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2012. http://www.nusl.cz/ntk/nusl-225572.
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Design of a new steel structure administrative building in Zlín. Structure is consist of three parts. The part A is designed of three fields in the transverse direction and five fields in the longitudinal direction. This part is two-storey. The part B is designed of two fields in the transverse direction and three fields in the longitudinal direction. This part is six-storey (five-storey). The part C is designed of two fields in the transverse direction and five fields in the longitudinal direction. This part is four-storey (three, two-storey). In both directions in all parts of the building is the distance between the columns in all fields of 6,0 meters. Structural elevation of all floors is 3,5 meters. Shape and dimension design. Fixed, utility, climatic load. The purpose is confrontation of inner forces and dimensioning of main supporting elements in three variations of structure. Comparsion of variations. More detailed static calculation, drawings for the selected variant. Detailed drawings for part of building.
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Kubíček, Michal. "Nosná konstrukce jízdárny." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2013. http://www.nusl.cz/ntk/nusl-226064.
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Master's thesis describes the design and check of the construction of the riding hall. Here are compared two versions the steel structure riding hall. For select version is here technical report, design calculation, statement of material and design documentation. Next is prepared specialization in the field of building construction.
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Smělíková, Petra. "Přemostění řeky Svitavy a tratě ČD v Blansku." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2015. http://www.nusl.cz/ntk/nusl-227189.
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The aim of the Diploma Thesis is elaboration of study of bridge crossing over the Svitava river and ČD railway track in Blansko. It concerns a five-pole steel beam road bridge with through-span which carries road of the third category. The static system of the construction is solved as solid-web beam of 1.3 meters height which is in three middle spans reinforced by truss construction with top chord and system of diagonals without verticals. The height of the main beam where reinforced by trusswork is 4.75 meters. The width of spans in the road axis is 18.5 + 30.525 + 44.4 + 30.525 + 18,5 metres. The bridge deck consists of steel cross beams bonded with reinforced concrete slab of 200 millimeters of thickness. The drive-through width of the roadway is 7.0 meters. The bridge is fitted with right-sided walkway placed on steel cantilevers. The walk-through width of the walkway is 3.0 meters. Material used is S355 Steel, C30/37 Concrete and S460 Steel which is used for marginal spans of the bridge. Load-bearing construction is assessed in compliance with current technical requirements laid down by European Directives, so called “Eurocodes”. The calculation of inner powers is performed using the Scia Engineer 2013.1 software.
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Ameli, Mostafa. "Heuristic Methods for Calculating Dynamic Traffic Assignment Simulation-based dynamic traffic assignment: meta-heuristic solution methods with parallel computing Non-unicity of day-to-day multimodal user equilibrium: the network design history effect Improving traffic network performance with road banning strategy: a simulation approach comparing user equilibrium and system optimum." Thesis, Lyon, 2019. http://www.theses.fr/2019LYSET009.
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Les systèmes de transport sont caractérisés de manière dynamique non seulement par des interactions non linéaires entre les différents composants, mais également par des boucles de rétroaction entre l'état du réseau et les décisions des utilisateurs. En particulier, la congestion du réseau impacte à la fois la répartition de la demande locale en modifiant les choix d’itinéraire et la demande multimodale globale. Selon les conditions du réseau, ils peuvent décider de changer, par exemple, leur mode de transport. Plusieurs équilibres peuvent être définis pour les systèmes de transport. L'équilibre de l'utilisateur correspond à la situation dans laquelle chaque utilisateur est autorisé à se comporter de manière égoïste et à minimiser ses propres frais de déplacement. L'optimum du système correspond à une situation où le coût total du transport de tous les utilisateurs est minimal. Dans ce contexte, l’étude vise à calculer les modèles de flux d'itinéraires dans un réseau prenant en compte différentes conditions d’équilibre et à étudier l’équilibre du réseau dans un contexte dynamique. L'étude se concentre sur des modèles de trafic capables de représenter une dynamique du trafic urbain à grande échelle. Trois sujets principaux sont abordés. Premièrement, des méthodes heuristiques et méta-heuristiques rapides sont développées pour déterminer les équilibres avec différents types de trafic. Deuxièmement, l'existence et l'unicité des équilibres d'utilisateurs sont étudiées. Lorsqu'il n'y a pas d'unicité, la relation entre des équilibres multiples est examinée. De plus, l'impact de l'historique du réseau est analysé. Troisièmement, une nouvelle approche est développée pour analyser l’équilibre du réseau en fonction du niveau de la demande. Cette approche compare les optima des utilisateurs et du système et vise à concevoir des stratégies de contrôle afin de déplacer la situation d'équilibre de l'utilisateur vers l'optimum du systèmeTransport systems are dynamically characterized not only by nonlinear interactions between the different components but also by feedback loops between the state of the network and the decisions of users. In particular, network congestion affects both the distribution of local demand by modifying route choices and overall multimodal demand. Depending on the conditions of the network, they may decide to change for example their transportation mode. Several equilibria can be defined for transportation systems. The user equilibrium corresponds to the situation where each user is allowed to behave selfishly and to minimize his own travel costs. The system optimum corresponds to a situation where the total transport cost of all the users is minimum. In this context, the study aims to calculate route flow patterns in a network considering different equilibrium conditions and study the network equilibrium in a dynamic setting. The study focuses on traffic models capable of representing large-scale urban traffic dynamics. Three main issues are addressed. First, fast heuristic and meta-heuristic methods are developed to determine equilibria with different types of traffic patterns. Secondly, the existence and uniqueness of user equilibria is studied. When there is no uniqueness, the relationship between multiple equilibria is examined. Moreover, the impact of network history is analyzed. Thirdly, a new approach is developed to analyze the network equilibrium as a function of the level of demand. This approach compares user and system optimums and aims to design control strategies in order to move the user equilibrium situation towards the system optimum
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Drexler, Martin. "Lávka pro pěší." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2014. http://www.nusl.cz/ntk/nusl-226916.
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This thesis deals with the design and assessment of the wooden footbridge. The structure is designed for the locality of the village Loučná nad Desnou acrros the river Desná. Span of the footbridge is 30m, and the width is 4m. The footbridge is covered with a saddle roof. The main supporting elements are two triple joint arcs with intermediate bridge deck. The bridge deck is made of two main beams and nine cross members, with always two longitudinal members in between them. Roofing is of nine cross-bindings, which are connected by purlins and top purlin. The stability of the whole structure is stiffened by the horizontal longitudinal stiffeners in the top and bottom surface and vertical longitudinal stiffener in the roof. The main load-bearing elements are made of glued laminated timber, the other elements are made of solid timber. Stiffeners are made of steel rods.
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Hrudík, Jan. "Přední náprava vysokovýkonného sportovního vozu." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2011. http://www.nusl.cz/ntk/nusl-443475.
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Tato diplomová práce byla psána při studentské zahraniční stáži, pod záštitou Evropské Unie – program „ERASMUS Student Mobility for Placement“. Stáž byla absolvována mezi prosincem 2010 a květnem 2011 ve společnosti a.d.Tramontana, mající sídlo v Palau de Santa Eulália, Španělsko. Pro kompletní návrh podvozku a odpružení jakéhokoli vozidla je nezbytná znalost mnoha technických disciplín. Tato diplomová práce se zabývá dvěma z nich – odpružení a řízení. Nejprve je rozebrána teorie, na kterou se může navázat v praktické části práce. Velká pozornost byla věnována srozumitelnosti textu a názornosti obrázků, bez zbytečných detailů, avšak bez vynechání důležitého. Tuto práci je tedy možné užít jako prvního kroku před návrhem podvozku. V další části je popsáno, jak byla probraná teorie využita při návrhu řízení u skutečného vozu, přičemž největší pozornost je věnována Ackermannově teorii řízení a geometrii zabraňující samořízení při propružení. V závěrečných částech je pozornost věnována ukázce některých z každodenních činností v malosériové výrobě automobilů – jde o zjištění maximálně možného pohybu kola při propružení a proces výroby příčných trojúhelníkových ramen včetně návrhu jejich připevnění k šasi.
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Луценко, Владислав Анатолійович, Владислав Анатольевич Луценко, and Vladyslav A. Lutsenko. "Наукові основи вдосконалення термомеханічної обробки катанки для сталевого дроту малого діаметру." Thesis, Запорізький національний технічний університет, 2015. http://eir.zntu.edu.ua/handle/123456789/417.
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Луценко, В.А. Наукові основи вдосконаленнятермомеханічної обробки катанки для сталевого дроту малого діаметру [Текст]: дис. … докт. техн. наук: 05.16.01 : захищена ....: затверджена…. /Луценко Владислав Анатолійович. – Запоріжжя, 2015. – 353 с.UK: Дисертаційна робота присвячена підвищенню в процесі ТМО пластичних властивостей сталевої катанки. Отримана сталева катанка має структуру: високовуглецева – дисперсний перліт із відсутністю замкнутої цементитної сітки, мінімальний зневуглецьований шар, який рівномірно розподілений по периметру; низьковуглецева – рівномірну структуру фериту з мінімальною кількістю перліту; легована – наявність бейніто-мартенситних ділянок до 10% в змішаній структурі. Результати використані на дротових станах ВАТ «БМЗ» та ПАТ «АрселорМіттал Кривий Ріг». Підвищення пластичності катанки забезпечило виготовлення сталевого дроту малого діаметру без проміжної термічної обробки, що дозволило знизити видатковий коефіцієнт металу в середньому на 10%. EN: The dissertation is devoted of increasing in thermo-mechanical processing the plastic properties of steel wire rod. The obtained steel wire rod has the structure: high carbon – the dispersion of perlite without closed cementite net, the minimum depth of equable decarburized layer; low carbon – uniform structure of ferrite with a minimum of perlite; alloy – the occurrence of bainite-martensite areas up to 10% in the mixed structure. The results were used on the rod mills OJSC “Byelorussian steel works” and РJSC “ArcelorMittalKryvyiRih“. The increasing of plasticity provided the production of steel wire of small diameter without intermediate heat treatment, thus reducing the expenditure coefficient of metal by 10% in average. RU: В диссертационной работе решена актуальная научно-техническая проблема – повышение после высокотемпературной прокатки пластических свойств металла путем развития научных основ о влиянии процессов ТМО на структурообразование и качественные характеристики стальной катанки. Установленные закономерности позволили совершенствовать технологию ТМО катанки и при экономии материальных ресурсов обеспечить производство стальной проволоки малого диаметра для металлокорда (в том числе сверхвысокопрочного), высокопрочной бортовой, канатной, легированной сварочной и низкоуглеродистой. Изучена кинетика превращения аустенита непрерывнолитой стали 90 при непрерывном охлаждении и в изотермических условиях. Установлено, что выделения цементита по границам зерен подавляются и полностью отсутствуют при скоростях более 10°С/с и при изотермическом распаде. Определено, что величина эффекта рекалесценции в стали 90 зависит от времени превращения. Установлено, что при ТМО снижение температуры после горячей деформации с 1050…1100°С до 900…950°С в результате принудительного охлаждения при повышении дробности деформации (на 20%) приводит к увеличению пластических свойств высокоуглеродистой стали. Полученная катанка для стальной проволоки, в отличие от традиционной, имеет повышенные пластические свойства. Основу структуры катанки составляет: высокоуглеродистой – сорбитообразный перлит (более 70%) с отсутствием избыточных структур (замкнутой цементитной сетки), минимальный обезуглероженный слой равномерно распределен по периметру; низкоуглеродистой – равномерная структура феррита с минимальным количеством пластинчатого перлита; легированной – наличие бейнито-мартенситных участков до 10% в смешанной структуре. Повышены требования к микроструктуре и свойствам высокоуглеродистой катанки и проволоки, которые отражены в изменении №11 к ЗТУ 840-03-2006 «Катанка стальная сорбитизированная для металлокорда, бортовой проволоки и проволоки для рукавов высокого давления» и ТУ У 276.3-23365425-638.2008 «Проволока стальная термически обработанная». Результаты использованы на ПАО «АрселорМиттал Кривой Рог» при разработке СТИ 228-112-2008 «Производство катанки из легированных сталей для сварочной проволоки ответственного назначения», изменения №3 к режимам охлаждения проката в потоке проволочного стана 150-1 СПЦ-1. Разработаны и внедрены на ОАО «БМЗ» режимы ТМО стальной катанки, в том числе для сверхвысокопрочной проволоки и металлокордапо ЗТУ 840-03-2006 (Изменения к ТК 840-П13-01-2002 и ТК 840-П3-01-2007 на режимы двухстадийного охлаждения катанки различного марочного сортамента в потоке стана 150). Повышение пластичности после высокотемпературной прокатки обеспечило изготовление стальной проволоки малого диаметра различного назначения без промежуточной термической обработки с сохранением требуемых конечных характеристик. Катанка, изготовленная по новому режиму ТМО, переработанная на проволоку малого диаметра, имеет лучшую технологичность в сравнении с базовой. Так, при производстве высокопрочногометаллокорда обрывность снизилась на 34%, а сверхвысокопрочного – на 23%. Освоение усовершенствованных режимов ТМО позволило снизить расходный коэффициент металла в среднем на 10%. Общий фактический экономический эффект от внедренных новых технологических решений составляет 31,7 миллиона гривен, доля автора – 4,44 миллиона гривен.
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Lečbych, Antonín. "Trojlodní objekt pro průmyslovou výrobu." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2015. http://www.nusl.cz/ntk/nusl-227558.
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The thesis contains the design and assessment of three-aisled steel building for small metal production. Supporting span of construction hall is 9, 18 and 9 m. In the middle wing is situated bridge crane with capacity of 2 tons. The estimated location of the object is Luhačovice. The initial design concept was specified by supervisor (as the idea of the investor/architect), for which was did static and structural solution and assembly details. For selected option was made a calculation of supporting structures and selected assembly details. The hall has a rectangular floor plan of 36x36m and ridge height is 9 m. The central wing is made of steel and side extensions are made of glued laminated timber.
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Ward, Nicholas Rhys. "The rate-limiting mechanism for the heterogeneous burning of iron in normal gravity and reduced gravity." Queensland University of Technology, 2007. http://eprints.qut.edu.au/16673/.
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This thesis presents a research project in the field of oxygen system fire safety relating to the heterogeneous burning of iron in normal gravity and reduced gravity. Fires involving metallic components in oxygen systems often occur, with devastating and costly results, motivating continued research to improve the safety of these devices through a better understanding of the burning phenomena. Metallic materials typically burn in the liquid phase, referred to as heterogeneous burning. A review of the literature indicates that there is a need to improve the overall understanding of heterogeneous burning and better understand the factors that influence metal flammability in normal gravity and reduced gravity. Melting rates for metals burning in reduced gravity have been shown to be higher than those observed under similar conditions in normal gravity, indicating that there is a need for further insight into heterogeneous burning, especially in regard to the rate-limiting mechanism. The objective of the current research is to determine the cause of the higher melting rates observed for metals burning in reduced gravity to (a) identify the rate-limiting mechanism during heterogeneous burning and thus contribute to an improved fundamental understanding of the system, and (b) contribute to improved oxygen system fire safety for both ground-based and space-based applications. In support of the work, a 2-s duration ground-based drop tower reduced-gravity facility was commissioned and a reduced-gravity metals combustion test system was designed, constructed, commissioned and utilised. These experimental systems were used to conduct tests involving burning 3.2-mm diameter cylindrical iron rods in high-pressure oxygen in normal gravity and reduced gravity. Experimental results demonstrate that at the onset of reduced gravity, the burning liquid droplet rapidly attains a spherical shape and engulfs the solid rod, and that this is associated with a rapid increase in the observed melting rate. This link between the geometry of the solid/liquid interface and melting rate during heterogeneous burning is of particular interest in the current research. Heat transfer analysis was performed and shows that a proportional relationship exists between the surface area of the solid/liquid interface and the observed melting rate. This is confirmed through detailed microanalysis of quenched samples that shows excellent agreement between the proportional change in interfacial surface area and the observed melting rate. Thus, it is concluded that the increased melting rates observed for metals burning in reduced gravity are due to altered interfacial geometry, which increases the contact area for heat transfer between the liquid and solid phases. This leads to the conclusion that heat transfer across the solid/liquid interface is the rate-limiting mechanism for melting and burning, limited by the interfacial surface area. This is a fundamental result that applies in normal gravity and reduced gravity and clarifies that oxygen availability, as postulated in the literature, is not rate limiting. It is also established that, except for geometric changes at the solid/liquid interface, the heterogeneous burning phenomenon is the same at each gravity level. A conceptual framework for understanding and discussing the many factors that influence heterogeneous burning is proposed, which is relevant to the study of burning metals and to oxygen system fire safety in both normal-gravity and reduced-gravity applications.
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Ward, Nicholas Rhys. "The rate-limiting mechanism for the heterogeneous burning of iron in normal gravity and reduced gravity." Thesis, Queensland University of Technology, 2007. https://eprints.qut.edu.au/16673/1/Nicholas_Ward_Thesis.pdf.
Full textAbstract:
This thesis presents a research project in the field of oxygen system fire safety relating to the heterogeneous burning of iron in normal gravity and reduced gravity. Fires involving metallic components in oxygen systems often occur, with devastating and costly results, motivating continued research to improve the safety of these devices through a better understanding of the burning phenomena. Metallic materials typically burn in the liquid phase, referred to as heterogeneous burning. A review of the literature indicates that there is a need to improve the overall understanding of heterogeneous burning and better understand the factors that influence metal flammability in normal gravity and reduced gravity. Melting rates for metals burning in reduced gravity have been shown to be higher than those observed under similar conditions in normal gravity, indicating that there is a need for further insight into heterogeneous burning, especially in regard to the rate-limiting mechanism. The objective of the current research is to determine the cause of the higher melting rates observed for metals burning in reduced gravity to (a) identify the rate-limiting mechanism during heterogeneous burning and thus contribute to an improved fundamental understanding of the system, and (b) contribute to improved oxygen system fire safety for both ground-based and space-based applications. In support of the work, a 2-s duration ground-based drop tower reduced-gravity facility was commissioned and a reduced-gravity metals combustion test system was designed, constructed, commissioned and utilised. These experimental systems were used to conduct tests involving burning 3.2-mm diameter cylindrical iron rods in high-pressure oxygen in normal gravity and reduced gravity. Experimental results demonstrate that at the onset of reduced gravity, the burning liquid droplet rapidly attains a spherical shape and engulfs the solid rod, and that this is associated with a rapid increase in the observed melting rate. This link between the geometry of the solid/liquid interface and melting rate during heterogeneous burning is of particular interest in the current research. Heat transfer analysis was performed and shows that a proportional relationship exists between the surface area of the solid/liquid interface and the observed melting rate. This is confirmed through detailed microanalysis of quenched samples that shows excellent agreement between the proportional change in interfacial surface area and the observed melting rate. Thus, it is concluded that the increased melting rates observed for metals burning in reduced gravity are due to altered interfacial geometry, which increases the contact area for heat transfer between the liquid and solid phases. This leads to the conclusion that heat transfer across the solid/liquid interface is the rate-limiting mechanism for melting and burning, limited by the interfacial surface area. This is a fundamental result that applies in normal gravity and reduced gravity and clarifies that oxygen availability, as postulated in the literature, is not rate limiting. It is also established that, except for geometric changes at the solid/liquid interface, the heterogeneous burning phenomenon is the same at each gravity level. A conceptual framework for understanding and discussing the many factors that influence heterogeneous burning is proposed, which is relevant to the study of burning metals and to oxygen system fire safety in both normal-gravity and reduced-gravity applications.
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Šašinka, Jakub. "Ocelová konstrukce vojenského muzea." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2015. http://www.nusl.cz/ntk/nusl-227198.
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The diploma thesis describes the design and assessment of steel structure of the roofing of the military museum in Králíky. The supporting structure of hall is 40.00 meters span. The total layout are 55.93 x 72.04 m, building height 11.43 m, 16.11 m pylon height. Main construction material is steel, grade S355, secondary constructions are made from steel grade S235, rods are made from steel grade S460. I did optimization of steel structure and chose the best option. For this option I made detailed structural analysis. It is prepared by static analysis of the main load-bearing parts of the structure, including joints and details. The supporting structure of hall consists in the transverse direction from the curved spatial lattice structure made of steel circular tubes which hang on rods on a sloped pylon. Part of the report is open-air roofing.
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MISHRA, SAURABH KUMAR. "AN OPTIMIZED PATH PLANNING ALGORITHM BASED ON SOFT COMPUTING." Thesis, 2018. http://dspace.dtu.ac.in:8080/jspui/handle/repository/16354.
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The existing guidance systems for panoramic areas facing various traversal problem during the path selection,whenever any path select by the Ant it is select only by seeing the lowest path cost. As we know very well that in particular panoramic spot,there are two type of roads, plane roads and other are steep roads,these steep roads some time are not suitable for children ortheageandalsoconsumehugeenergybytouristvehicle. Theexistingguidancesystemsfor panoramic areas facing various traversal problem during the path selection. Traditional path planning algorithm focus on shortest path but they did not focus on tourist demand,it means formermethodologybasedonbeststrategyinsteadofoptimal. Ourproposedmethodologyfor path selection of tourist vehicle based on two parameter: link steep probability which is based on steep angle and steep cost of link. If Ant want to go from node i to node j then first of all it will compare all value of steep probability and steep cost,the value which is very less as compare to other values then this min value link will be selected by ant and Pheromone rate on this link will be more as compare to others links. This modification in previous methodology will surely increase the performance of our algorithm ,hence this algorithm has given better optimal route for tourist with less time, cost and energy consumption as well as tourist requirements.
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tien, Chiang shih, and 江仕添. "A Case Study of Biotechnical Retaining Structures in Steep Slopes-Widening of the Tao-Chu Road #20." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/96136886358399154531.
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碩士中華大學
土木工程學系碩士班
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This study evaluates the optimum retaining structure system by investigating the soil characteristics and the useable lands along the slope of widening of the Tao-Chu Road #20, Taoyuan County, Taiwan. The evaluated factors include: cost, materials specification, availability of on-site materials, construction difficulty, inspection, risk potential, vegetation, environment & landscape, acceptability by residence, maintenance & management. Among the three different types of retaining structures, namely, reinforced soil wall, stone wall, and sandwiched wall, the above 10 factors are evaluated and the reinforced soil wall is considered the optimum ecological engineering method. Due to the elevation difference of more the 10 m, and the space constraint, the stone wall is unsuitable due to its stable high limitation of only 3m. Sandwiched wall is also unsuitable because of its big volume of rigid gravity wall, necessity of piling and uneconomic in cost. The reinforced soil wall, on the other hand, is flexible wall and the earth pressure could be reduced due to some allowable lateral deformation. Besides, it has several other advantages, such as high earthquake resistance, rapid construction, unnecessities of heavy construction equipments and very skillful workers, and the possibility of building very high wall, etc. Besides, since the geogrid has openings, spreading the weeds and cohesive soils will allow vegetation to grow. When the vegetation grows, not only green and beautiful, it also provides the nest for small animals and bugs to reside. Keywords: road widening, biotechnical retaining structures, reinforced soil walls, ecological engineering.