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Oprávnění stavět a stavby na cizích pozemcích / Building licence and structures on the land of anotherBorošová, Tereza January 2013 (has links)
The thesis is focused on ways of formation of permissions to build and the possibilities of settlement of authorized and unauthorized structures, which are established on extraneous grounds. It also defined important terms such as the concept of land, construction or the principle of superficies non solo cedit. Part of the thesis include historical development of the ownership of land and buildings located on them. Essential part of the thesis deals with changes that will bring the effectiveness of a new Civil Code.
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Sobre o projeto e a construção de estruturas metálicas espaciais / About the design and construction of metal space structuresMagalhães, João Ricardo Maia de 18 September 1996 (has links)
O presente trabalho aborda alguns aspectos estruturais e construtivos das estruturas metálicas espaciais. Inicialmente apresentam-se um breve histórico deste sistema estrutural, algumas informações gerais a respeito das classificações das estruturas espaciais, das \'tipologias\' para alguns dos sistemas mais utilizados, assim como exemplos de aplicação destas estruturas. A seguir discutem-se aspectos relativos à análise estrutural, com a apresentação de um breve roteiro de cálculo para uma cobertura em treliça espacial. Finalmente apresentam-se alguns resultados teóricos e experimentais relativos a barras comprimidas de inércia variável ao longo do comprimento. / In this work, some structural and constructional aspects of metal space structures are presented. lnitially, a brief review of this structural system is described together with some general informations about classifications, types and applications of usual systems. In addition, some aspects about structural analysis are discussed, presenting a brief guide for a space truss design. Finally, some theoretical and experimental results are illustrated for a case of axial compression members with variable stiffness.
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Análise numérica de seções transversais e de elementos estruturais de aço e mistos de aço e concreto em situação de incêndio / Numerical analysis of steel and composite steel-concrete cross sections and structural elements in fire situationRegobello, Ronaldo 07 March 2007 (has links)
O presente trabalho teve como objetivo principal estudar, em caráter essencialmente numérico via ANSYS v9.0, a elevação de temperatura em seções transversais de elementos estruturais de aço e mistos de aço e concreto, com vistas a uma avaliação das equações propostas pelo método simplificado de cálculo da NBR 14323:1999, em especial, para situações em que não ocorra aquecimento uniforme por todos os lados do elemento. São apresentados modelos numéricos de seções transversais de elementos estruturais de aço, mistos de aço e concreto e, em caráter complementar, de madeira, em situação de incêndio, para avaliar a evolução dos níveis de temperatura ao longo do tempo. São também construídos e analisados modelos numéricos com vistas à análise do efeito da elevação de temperatura no comportamento mecânico em vigas de aço de um edifício de interesse. A determinação dos níveis de temperatura em seções transversais de elementos estruturais, obtidas com base nas prescrições normativas da NBR 14323:1999, conduzem a resultados satisfatórios, porém, com temperaturas próximas as temperaturas máximas obtidas numericamente. Para os casos usuais não contemplados pela NBR 14323:1999 fica evidente a necessidade do emprego de modelo avançado de cálculo ou de estudos com vistas ao desenvolvimento de ferramentas analíticas para emprego em tais situações. Com relação à análise do efeito da elevação de temperatura no comportamento mecânico, os fatores de redução de resistência para as vigas em situação de incêndio obtidos via ANSYS resultaram inferiores àqueles obtidos via TCD v5.0, com base na análise da seção transversal e procedimentos normativos. / This research presents a study, within the context of numerical analysis with ANSYS v9.0, in which the main goal has been driven to obtain the rise of temperature in steel and composite steel-concrete structural elements cross sections with the purpose of evaluating the temperature determination by normative equations proposed in brazilian standard NBR 14323:1999, considering the simple calculation model, specially in situations with not uniform exposition of the elements cross sections to the fire. Numerical models of steel, composite steel-concrete and wooden structural elements cross sections in fire situation are presented to evaluate the levels of temperature throughout the time. Numerical models to analyze the effect of the rise of temperature in the mechanical behavior of steel beams of a building of interest are also presented. The temperature levels obtained for structural elements by prescriptions of NBR 14323:1999 lead to satisfactory results but with temperatures near to the maximum temperatures obtained numerically. For the usual cases not contemplated by the NBR 14323:1999, is evident the necessity of employing advanced calculation models or studies for the development of analytical methods for such situations. With respect to the analysis of temperature rising effects in the mechanical behavior, the reduction factors for the resistance in fire situation, obtained by ANSYS, resulted smaller than those ones obtained by TCD v5.0, with base on the analysis of elements cross sections and normative procedures.
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Dynamically installed anchors for floating offshore structuresRichardson, Mark Damian January 2008 (has links)
The gradual depletion of shallow water hydrocarbon deposits has forced the offshore oil and gas industry to develop reserves in deeper waters. Dynamically installed anchors have been proposed as a cost-effective anchoring solution for floating offshore structures in deep water environments. The rocket or torpedo shaped anchor is released from a designated drop height above the seafloor and allowed to penetrate the seabed via the kinetic energy gained during free-fall and the anchors self weight. Dynamic anchors can be deployed in any water depth and the relatively simple fabrication and installation procedures provide a significant cost saving over conventional deepwater anchoring systems. Despite use in a number of offshore applications, information regarding the geotechnical performance of dynamically installed anchors is scarce. Consequently, this research has focused on establishing an extensive test database through the modelling of the dynamic anchor installation process in the geotechnical centrifuge. The tests were aimed at assessing the embedment depth and subsequent dynamic anchor holding capacity under various loading conditions. Analytical design tools, verified against the experimental database, were developed for the prediction of the embedment depth and holding capacity.
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Modélisation et simulation numérique de vibrations induites par écoulements autour d'obstacles cylindriques seuls ou en réseauxJus, Yoann 13 December 2011 (has links) (PDF)
Le travail engagé dans cette thèse s'inscrit dans le cadre de programmes de recherche engagés par les industriels du domaine nucléaire visant à optimiser les capacités prédictives des modèles de dimensionnement de composants de centrales nucléaires. La modélisation de l'action exercée par le fluide en écoulement et de la rétroaction induite par la dynamique de la structure est un élément clef du dimensionnement. L'objectif de la thèse est de mettre en évidence l'interaction entre la turbulence proche paroi et les effets de couplage instationnaire non conservatif potentiellement déstabilisant. Le cas particulier d'un cylindre seul en milieu infini, soumis à un écoulement transverse, est examiné en statique, puis en dynamique. L'influence des régimes d'écoulement sur la réponse dynamique est caractérisée. La quantification de l'énergie d'interaction fluide-structure est évaluée. Ce mémoire de thèse s'achève par une ouverture au cas du réseau de cylindres et démontre l'apport de macro simulations tridimensionnelles pour l'analyse des vibrations de struc- tures induites par écoulement en régime sous-critique dans un cadre HPC et l'intérêt du couplage CFD/CSM dans le cas d'écoulements turbulents en environnement industriel.
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Compliant shell mechanismsSeereeram, Videsh Ramjas January 2012 (has links)
No description available.
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Análise numérica de seções transversais e de elementos estruturais de aço e mistos de aço e concreto em situação de incêndio / Numerical analysis of steel and composite steel-concrete cross sections and structural elements in fire situationRonaldo Regobello 07 March 2007 (has links)
O presente trabalho teve como objetivo principal estudar, em caráter essencialmente numérico via ANSYS v9.0, a elevação de temperatura em seções transversais de elementos estruturais de aço e mistos de aço e concreto, com vistas a uma avaliação das equações propostas pelo método simplificado de cálculo da NBR 14323:1999, em especial, para situações em que não ocorra aquecimento uniforme por todos os lados do elemento. São apresentados modelos numéricos de seções transversais de elementos estruturais de aço, mistos de aço e concreto e, em caráter complementar, de madeira, em situação de incêndio, para avaliar a evolução dos níveis de temperatura ao longo do tempo. São também construídos e analisados modelos numéricos com vistas à análise do efeito da elevação de temperatura no comportamento mecânico em vigas de aço de um edifício de interesse. A determinação dos níveis de temperatura em seções transversais de elementos estruturais, obtidas com base nas prescrições normativas da NBR 14323:1999, conduzem a resultados satisfatórios, porém, com temperaturas próximas as temperaturas máximas obtidas numericamente. Para os casos usuais não contemplados pela NBR 14323:1999 fica evidente a necessidade do emprego de modelo avançado de cálculo ou de estudos com vistas ao desenvolvimento de ferramentas analíticas para emprego em tais situações. Com relação à análise do efeito da elevação de temperatura no comportamento mecânico, os fatores de redução de resistência para as vigas em situação de incêndio obtidos via ANSYS resultaram inferiores àqueles obtidos via TCD v5.0, com base na análise da seção transversal e procedimentos normativos. / This research presents a study, within the context of numerical analysis with ANSYS v9.0, in which the main goal has been driven to obtain the rise of temperature in steel and composite steel-concrete structural elements cross sections with the purpose of evaluating the temperature determination by normative equations proposed in brazilian standard NBR 14323:1999, considering the simple calculation model, specially in situations with not uniform exposition of the elements cross sections to the fire. Numerical models of steel, composite steel-concrete and wooden structural elements cross sections in fire situation are presented to evaluate the levels of temperature throughout the time. Numerical models to analyze the effect of the rise of temperature in the mechanical behavior of steel beams of a building of interest are also presented. The temperature levels obtained for structural elements by prescriptions of NBR 14323:1999 lead to satisfactory results but with temperatures near to the maximum temperatures obtained numerically. For the usual cases not contemplated by the NBR 14323:1999, is evident the necessity of employing advanced calculation models or studies for the development of analytical methods for such situations. With respect to the analysis of temperature rising effects in the mechanical behavior, the reduction factors for the resistance in fire situation, obtained by ANSYS, resulted smaller than those ones obtained by TCD v5.0, with base on the analysis of elements cross sections and normative procedures.
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Sobre o projeto e a construção de estruturas metálicas espaciais / About the design and construction of metal space structuresJoão Ricardo Maia de Magalhães 18 September 1996 (has links)
O presente trabalho aborda alguns aspectos estruturais e construtivos das estruturas metálicas espaciais. Inicialmente apresentam-se um breve histórico deste sistema estrutural, algumas informações gerais a respeito das classificações das estruturas espaciais, das \'tipologias\' para alguns dos sistemas mais utilizados, assim como exemplos de aplicação destas estruturas. A seguir discutem-se aspectos relativos à análise estrutural, com a apresentação de um breve roteiro de cálculo para uma cobertura em treliça espacial. Finalmente apresentam-se alguns resultados teóricos e experimentais relativos a barras comprimidas de inércia variável ao longo do comprimento. / In this work, some structural and constructional aspects of metal space structures are presented. lnitially, a brief review of this structural system is described together with some general informations about classifications, types and applications of usual systems. In addition, some aspects about structural analysis are discussed, presenting a brief guide for a space truss design. Finally, some theoretical and experimental results are illustrated for a case of axial compression members with variable stiffness.
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Analyse de quelques éléments du comportement des écrans de filets pare-blocs / Analysis of some elements of the behaviour of soft rockfall barriersGhoussoub, Leyla 01 December 2014 (has links)
Les écrans de filets pare-blocs sont des structures complexes hétérogènes formés d'un filet métallique maintenu par des câbles, des poteaux et des haubans munis de dissipateurs d'énergie. Le filet intercepte la trajectoire du bloc rocheux et résiste à sa perforation en dissipant l'énergie cinétique de l'impact dans les différents éléments de la structure. Le problème de modélisation posé par ces structures met en jeu de nombreuses non-linéarités tant matérielles que géométriques : l'impact dynamique rapide, les grandes déformations du filet et des câbles, les glissements et les frottements (dans le filet, du filet sur les câbles ou des câbles sur les supports), la plastification du filet ou des éléments dissipateurs, ainsi qu'un très grand nombre de paramètres géométriques ou technologiques (type de filet, type de dissipateur, type d'architecture de kit).Les travaux de doctorat présentés ici proposent deux nouvelles approches pour la modélisation numérique de deux principaux éléments du comportement des écrans de filets pare-blocs : les propriétés élastiques intrinsèques des filets et l'effet rideau, c'est-à-dire le glissement du filet sur les câbles de rives. Sur le premier point, il est à noter que les recherches qui ont été consacrées jusqu'à présent à l'étude du filet se concentrent pour l'essentiel sur des typologies particulières. Dans ce travail, les propriétés intrinsèques des différentes technologies de filets sont déterminées à l'aide de la méthode d'homogénéisation des milieux périodiques discrets dans laquelle chaque filet est remplacé par une membrane homogène. Une comparaison des comportements non-linéaires des principales technologies de filets est effectuée et met en évidence des différences remarquables dans la distribution des efforts aux bords de chaque filet et les caractéristiques des déformations. Concernant le deuxième point, plusieurs études ont montré l'importance de la modélisation des câbles glissants pour reproduire le comportement réel de la structure. Dans la deuxième partie de la thèse, l'effet rideau est modélisé. Un modèle analytique de câble glissant à « n » nœuds est développé. Ensuite, ce modèle est implémenté dans un algorithme numérique mettant en œuvre une utilisation avancée du logiciel de calcul par éléments finis code-aster en statique et en dynamique. Cet algorithme est validé par des calculs analytiques et les limites de la méthode utilisée sont exposées. Enfin, des tests numériques sont conduits sur des modèles de filets en tenant compte de l'effet rideau pour évaluer l'influence du modèle développé sur les résultats. Des remarques, observations et conseils sont déduits afin d'aboutir à un outil numérique d'aide à la conception des écrans de filets pare-blocs / Soft rockfall barriers are complex structures that generally consist of a metallic net supported by steel posts and cables with brake elements. Several experimental and numerical studies have been carried out to evaluate their behaviour and a technical agreement in EU was recently established to certify these barriers based on experimental tests. Actually, manufacturers develop rockfall kits with their own technical specificities. The objective of the present work is to determine the intrinsic properties of most common nets technologies and to investigate their influence on the overall mechanical behaviour of the structure. To this end, a comprehensive comparison between the local behaviours of the different nets is first presented using equivalent homogeneous membranes. Results derived for square nets under static concentrated loading illustrate the influence of the manufacturing technology on the deflection and stresses distribution. Then, a numerical and analytical model for the so-called “curtain effect” is developed and validated. It is focused on the capacity of the proposed methodology to study and evaluate the response of the whole barrier
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Influence of Consolidation and Interweaving on Compression Behavior of IsoTruss™ StructuresHansen, Steven Matthew 09 March 2004 (has links) (PDF)
Composite IsoTruss™ structures incorporate intersecting longitudinal and helical members. At the intersections, the fiber tows can be interwoven to achieve mechanical interlocking for increased joint integrity. Interlocking introduces gaps and curvilinear fiber paths similar to the crossovers in filament-wound structures, potentially facilitating local delamination within the members, thus reducing the strength and/or damage tolerance of the structure. Optimizing the interlocking pattern at the joints along with efficient consolidation minimizes these effects.
Joint specimens were fabricated using a specially designed machine. Specific tow intersection patterns at the joint were: 1) Completely encapsulating the longitudinal member with the tows of the helical member; and 2) Interweaving the tows of the helical member with the tows of the longitudinal member. Consolidation was accomplished using: 1) a braided sleeve; 2) a coiled sleeve; 3) a sparse spiral Kevlar® wrap; 4) a polyester shrink tape sleeve; 5) twisting the entire bundle of longitudinal fiber tows; and 6) cinching the joints using aramid fiber.
Ultimate compression strength and stiffness is directly related to the straightness of the tows in the longitudinal members at the intersections. An encapsulated joint reduces member strength by only 4.6%; whereas, an interwoven joint reduces member strength by 30.5%. The fiber paths of the longitudinal member in encapsulated joints are straighter than in interwoven joints, resulting in an average strength difference of 26.2%.
Physical properties, strength, and stiffness show that consolidation quality directly affects performance. Consolidation using sleeves provides high quality consolidation, high strength, and high stiffness. Encapsulated joints consolidated using sleeves have an average ultimate strength and Young's modulus 34% and 21% higher, respectively, than encapsulated joints consolidated using other methods. Interwoven joints consolidated using sleeves have an average ultimate strength and Young's modulus 28% and 19% higher, respectively, than interwoven joints consolidated using other methods. Consolidating specimens using a braided sleeve yields the highest quality based on consistency, strength, and stiffness. Consolidating specimens by twisting the longitudinal member yields the lowest strength and stiffness. These conclusions will be applied to IsoTrussâ„¢ grid structure design and manufacturing technology.
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