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Submitted by Rafael Santana (rafael.silvasantana@ufpe.br) on 2017-07-10T19:03:34Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Dissertação. Maria Carolina. PPGEMinas.pdf: 3730779 bytes, checksum: 8594f4287f485aa5df1cc1b54795320a (MD5) / Made available in DSpace on 2017-07-10T19:03:35Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Dissertação. Maria Carolina. PPGEMinas.pdf: 3730779 bytes, checksum: 8594f4287f485aa5df1cc1b54795320a (MD5) Previous issue date: 2016-07-14 / CAPES / A análise estrutural de um maciço rochoso tem por finalidade fornecer elementos para uma melhor compreensão dos parâmetros de descontinuidades. Salienta-se que o controle destes parâmetros constitui o norte científico para orientar a lavra de rochas ornamentais, pois, as dimensões e qualidade dos blocos obtidos dependem principalmente da natureza e equidistância dos fraturamentos associados à distribuição das tensões atuantes em um maciço rochoso. Neste trabalho, apresenta-se a análise estrutural do Sienito Marrom Imperial, localizado em Umari, zona rural do Município de João Alfredo – PE. Ao fornecer tais informações o responsável técnico poderá definir a melhor sistemática tecnológica no plano de aproveitamento econômico a ser adotado, sem provocar o aparecimento de fraturas de alívio na rocha. Os dados coletados durante a visita técnica constituíram um banco de dados utilizado na determinação das projeções estereográficas (rede de Schmidt) e diagramas de rosetas. A análise do fraturamento mostrou que as fraturas de cisalhamento situam-se nas direções 30º Az e 340º Az. A bissetriz do ângulo formado pelo cruzamento destes cisalhamentos corresponde à direção de compressão máxima atuante representada por 1 e disposta na direção 5°Az. Perpendicularmente a essa, encontra-se a direção de distenção, 3. Com base no exposto pode-se concluir que a melhor orientação de corte, para o desenvolvimento dos trabalhos de abertura da pedreira, de modo a provocar o alivio das tensões e evitar o aparecimento de fraturas durante os serviços de lavra, é a direção SE-NW. Quanto à caracterização tecnológica, os resultados obtidos foram comparados aos estabelecidos pelas normas ABNT NBR 15844:2010, NBR 12042: 1992 e ASTM C 615:1992. Os índices físicos - massa específica aparente seca e saturada, porosidade e absorção aparentes - atenderam satisfatoriamente aos requisitos da ABNT NBR 15844:2010 e americana ASTM C615: 1992. Os resultados dos ensaios de resistência à compressão simples e resistência à flexão quando comparados com os valores requisitados para granitos, mostram que a rocha suporta uma compressão mediana, levemente inferior ao estabelecido por estas normas. Já o ensaio de desgaste Amsler ficou abaixo de 1mm/m, como especificado pela norma brasileira NBR 15844:2010. A avaliação dos ensaios do Marrom Imperial, juntamente com a análise petrográfica, possibilitou um melhor conhecimento da inter-relação dos resultados, e podendo assim relacionar diretamente a uma melhor aplicação do material objeto de estudo. A rocha pode ser aplicada sem restrições, salvo locais úmidos que requerem impermeabilização e de intenso tráfego. / Structural analysis of a rock mass is intended to provide elements for a better understanding of discontinuities parameters. It is noted that the control of these parameters is the scientific north to guide the mining of dimension stones, therefore, the size and quality of the blocks obtained depend mainly on the nature and equidistance of fracturing associated with the distribution of stresses acting on a rock mass. In this paper is presented a structural analysis of the Syenite Brown Imperial, located in Umari, rural municipality of Joao Alfredo - PE. By providing such information the responsible technician can determine the best technology in the systematic economic exploitation plan to be adopted, without causing the onset of relief of fractures in the rock. The data collected during the technical visit constituted a database used in determining the stereographic projections (Schmidt network) and rosettes diagrams. The analysis of fracturing showed that shear fractures are located in directions 30º and Az 340º Az. The bisecting the angle formed by the intersection of these shear is the maximum active compression direction represented by 1 and arranged in 5 ° Az direction. Perpendicular to this, it is the direction of distention, 3. Based on the above it can be concluded that the best cutting guidance for the development of the opening work of the quarry, so as to cause the relief of the stresses and prevent the occurrence of fracture during the mining services is the direction SE- NW. As for technological characterization, the results were compared to the standards established by the NBR 15844: 2010, NBR 12042: 1992 and ASTM C 615: 1992. Physical indices - apparent dry and saturated especific mass, porosity and apparent absorption - satisfactorily met the requirements of NBR 15844: 2010 and American ASTM C615: 1992. The results of tests on the compressive strength and flexural strength when compared to the values required to granites, showed rock that supports a median compression, slightly lower than that established by these standards. However Amsler wear test was less than 1 mm / m, as specified by the Brazilian standard NBR 15844: 2010. The evaluation of the tests of the Imperial Brown, along with petrographic analysis enabled a better understanding of the interrelationship of the results, and thus being able to relate directly to a better implementation of the object of study material. The rock can be applied without restriction, except wet locations that require waterproofing and high traffic.

Content: Soluble soybean polysaccharide (SSPS) is good in emulsification, and stable emulsion may be formed with the addition of SSPS in fatliquoring agents. In this paper, with wet blues as raw materials, after being retanned and neutralized, fatliquoring and filling up with SSPS were carried out at the same time, with different amounts of SSPS, i.e., 1%, 3%, 5%,7% in weight. The leather samples were dried at room temperature. The effects of SSPS amounts on the thickness, air permeability and water vapor permeability of the crust leather were studied. The tensile properties of the leathers filled by SSPS were analyzed. The results indicated that with increasing the amounts of SSPS, the thickness and the water vapor permeability of the leathers increase, while the air permeability decreases slightly. The maximum stress-strain capacity of leathers decreases with increasing the SSPS amount. At the SSPS amount of 3%, the leather is good in softness, as well as in physical and mechanical properties. Take-Away: 1.SSPS from soybean dregs is an acidic polysaccharide, which is rich in raw materials and low in cost. 2.Leathers filled with SSPS have good performance.

This Master’s thesis deals with strain-stress analysis of a spine segment with an introduced fixator and a spine in natural physiological state. The work starts with a research study of literature sources that focus on similar issues. Furthermore, basic anatomy terminology and basic procedures for human spine stabilization were described. The formulated issue was resolved by computational modelling with the use of the finite element method. This solution requires a suitable computational model to be produced. This model consists of partial geometry, material, bond, and loading models. The geometric model was produced on the basis of CT scan images of a 60-year-old man which were used for producing five spine vertebrae T11–L3. Moreover, the geometric model consists of four intervertebral discs and eight articular cartilages. The material model includes homogeneous, heterogeneous and degraded properties of bone tissue. The strain-stress analysis was performed for seven loading states, which concern basic movements of human spine – standing, bending forward, bending backwards, bending left, bending right, left rotation and right rotation, with the use of ANSYS software. The assessed and analysed quantities include spine segment displacement, contact pressure of articular cartilages and stress on the fixator.

The diploma thesis deals with computational modelling of stress-strain states in elastomeric components of a flexible coupling. The first part of the thesis is dedicated to research about usage and designs of flexible coupling and about fatigue of elastomers. The second part of the thesis concerns creation of the computational model. The model of material is determined based on uniaxial tension test of a specimen produced from a real elastomer component. The results are presented in the form of comparison of two designs of elastomer component with respect to fatigue behaviour based on a maximum principal strain range. The results of computational modelling in the viewpoint of crack initiation site are in good agreement with the results from the component used in operation and dif-ferences between the two designs are negligible. The quantitative difference of the two designs is 15 %.

In a family house not far from Brno, there is an entryway hole for getting into the space under the floor. The hole is covered by a high weight concrete hatch. For easier manipulation with the hatch an opening mechanism was designed and manufactured. This mechanism had been installed under the hatch and nowadays it works well. This master’s thesis deals with description of main components of the mechanism and their function. Load analysis and stress-strain analysis are the major part of this thesis. At the end of this work the analysis results are commented and some suggestions for further research are proposed.

This master´s thesis is focused on biomechanical study of wrist. There is a literature search on this theme in the beginning of this work. The thesis is described in detail anatomy of bones in the wrist. Subsequent the stress-strain analysis of physiological wrist is implemented in a neutral position. The model of geometry of wrist is created on base of CT data. To create calculation model and the solution is implemented in the computer system ANSYS Workbench.

The thesis is focused on expanding the ends of the tubes made of 1.4031 material into a cone shape for quasi-static and dynamic conditions. The aim of the research is the analysis of stress-strain condition in the area formed under the process conditions. As a technology test for expanding tubes is used a method of pushing the tube at a stationary mandrel and deformation measurement was done by 3D optical system ARAMIS. In the thesis is described in detail an experiment carried out under quasi-static conditions, the results of which yielded interesting findings. In the framework of the present study were designed and detailed engineering design and production tools designed for experimental realization of technological tests for quasi-static and dynamic conditions. Exploration in terms of the behavior of tube under dynamic conditions forming in this thesis is carried out in phase functional verification tools. The analysis of the forming process is planned in the framework of the next thesis.

Yes / Recycled aggregate concrete filled stainless steel tube (RAC-FSST) is a new type of composite member combining the advantage of stainless steel and RAC. In this paper, a total of twenty-four RAC-FSST stub columns were tested under axial load, considering the influences of coarse recycled aggregate (CRA) content, steel ratios and compressive strengths of RAC. The obtained results, including the failure patterns, responses of axial load vs. deformation, stress states of external stainless steel tube and inner RAC and confinement effects, were systematically analyzed. Results indicated that all specimens presented good ductility and high residual strengths after reaching the maximum axial load. The elastic stiffness of RAC-FSSTs obviously declined with the increasing CRA content, while the strain at the ultimate load was larger. The inclusion of CRA could advance the occurrence of the confinement and lead to lower confining stress. Based on the experimental results, an analytical model with consideration of confinement action was developed to predict the axial response of RAC-FSST stub columns. Besides, the current design provisions for the normal CFST and RAC-FST members were employed to evaluate their applicability to RAC-FSSTs. In general, the design rules EN 1994-1-1:2004, GB 50936-2014 and T/CECS 625-2019 gave a conservative and relatively accurate prediction on ultimate strength of RAC-FSST stub columns. / This work was supported by the National Natural Science Foundation.

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