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The work is focused on assessing the structure of urban winter stadium, which will be located in Brno - Komarov. Winter stadium is designed according to standarts of ice hockey with a capacity of approximately 7 000 spectators. Of the 5 850 seating, 1 050 stalls and 100 in the VIP areas. Construction of hockey stadium is made of steel and steel-concrete columns, which together with composit transverse beam, reinforced concrete slab and bracings provide rigidity. Columns are supported by a set of bored piles with capitals. Roofing of the main part of the winter stadium is designed using a flat space frame having a maximum height of 4,5 m. Roof for entrance halls are design by a system of truss girder and purlins, which are hardened bracings to increase spatial rigidity. The structures are made of steel S 355 and concrete C 25/30. For designing steel structures was used software Scia ENGINEER and IDEA RS. Steel columns and composit beams are calculated by hand calculation. The total length of the hockey stadium is 111,5 meters, width outside the entrance hall is 82,02 m and the total width at the entrance hall is 96,85 m. The height of the building at the highest point is 25,6 meters.

Este trabalho objetivou o estudo dos edifícios de múltiplos andares constituídos por elementos mistos aço-concreto, com enfoque acadêmico, porém abordando aspectos e recomendações normativas diretamente aplicadas na prática corrente da engenharia estrutural. A revisão bibliográfica foi realizada com base em estudos acadêmicos e normativos além do estudo de um edifício exemplo constituído por elementos mistos. Os elementos mistos lajes, vigas e pilares foram abordados inicialmente de forma isolada, com base nas recomendações normativas, sendo que ao final os elementos foram interligados, apresentando ao leitor os principais aspectos teóricos e normativos para o dimensionamento de um edifício completo constituído de elementos estruturais mistos. / This study aims the multiple storey buildings formed by composite elements steel-concrete, with academic emphasis, however approaching standard recommendations and aspects directly applied to the structural engineering. A bibliographic review based on academic and standard studies was made, besides the design of an example building formed by composite elements. The composite elements: slabs, beams and columns were firstly approached based on standard aspects, and in the end, the elements were interconnected and presented to the reader the main theoretical and standard aspects to the design of a complete building formed by composite structural elements.

Advances in the design and manufacturing technologies have greatly enhanced the utility of fiber reinforced composite materials in aircraft, helicopter and space- craft structural components. The special characteristics of composites such as high strength and stiffness, light-weight corrosion resistance make them suitable sub- stitute for metals/metallic alloys. However, composites are very sensitive to the anomalies induced during their fabrication and service life. Also, they are suscepti- ble to the impact and high frequency loading conditions because the epoxy matrix is at-least an order of magnitude weaker than the embedded reinforced carbon fibers. On the other hand, the carbon based matrix posses high electrical conductivity which is often undesirable. Subsequently, the metal matrix produces high brittleness. Var- ious forms of damage in composite laminates can be identified as indentation, fiber breakage, matrix cracking, fiber-matrix debonding and interply disbonding (delam- ination). Among all the damage modes mentioned above, delamination has been found to be serious for all cases of loading. They are caused by excessive interlaminar shear and normal stresses. The interlaminar stresses that arise in the case of composite materials due to the mismatch in the elastic constants across the plies. Delamination in composites reduce it’s tensile and compressive strengths by consid- erable margins. Hence the knowledge of these stresses is the most important aspect to be looked into. Basic theories like the Euler-Bernoulli’s theory and Timoshenko beam theory are based on many assumptions which poses limitation to determine these stresses accurately. Hence the determination of these interlaminar stresses accurately requires higher order theories to be considered. Most of the conventional methods of determination of the stresses are through the solutions, involving the trigonometric series, which are available only to small and simple problems. The most common method of solution is by Finite Element (FE) Method. There are only few elements existing in the literature and very few in the commercially available finite element software to determine the interlaminar stresses accurately in the composite laminates. Accuracy of finite element solution depends on the choice of functions to be used as interpolating polynomials for the field variable. In-appropriate choice will manifest in the form of delayed convergence. This delayed convergence and accuracy in predicting these stresses necessiates a formulation of elements with a completely new concept. The delayed convergence is sometimes attributed to the shear locking phenomena, which exist in most finite element formulation based on shear deformation theories. The present work aims in developing finite elements based on higher order theories, that alleviates the slow convergence and achieves the solutions at a faster rate without compromising on the accuracy. The accuracy primarily depends on the theory used to model the problem. Thus the basic theories (such as Elementary Beam theory and Timoshenko Beam theory) does not suffice the condition to accuratley determine the interlaminar stresses through the thickness, which is the primary cause for delamination in composites. Two different elements developed on the principle of super-convergence has been presented in this work. These elements are subjected to several numerical experiments and their performance is assessed by comparing the solutions with those available in literature. Spacecraft and aircraft structures are light in weight and are also lightly damped because of low internal damping of the material of construction. This increased exibility may allow large amplitude vibration, which might cause structural instability. In addition, they are susceptible to impact loads of very short duration, which excites many structural modes. Hence, structural dynamics and wave propagation study becomes a necessity. The wave based techniques have found appreciation in many real world problems such as in Structural Health Monitoring (SHM). Wave propagation problems are characterized by high frequency loads, that sets up stress waves to propagate through the medium. At high frequency, the wave lengths are small and from the finite element point of view, the element sizes should be of the same order as the wave lengths to prevent free edges of the element to act as a free boundary and start reflecting the stress waves. Also longer element size makes the mass distribution approximate. Hence for wave propagation problems, very large finite element mesh is an absolute necessity. However, the finite element problems size can be drastically reduced if we characterize the stiffness of the structure accurately. This can accelerate the convergence of the dynamic solution significantly. This can be acheived by the super-convergent formulation. Numerical results are presented to illustrate the efficiency of the new approach in both the cases of dynamic studies viz., the free vibration study and the wave propagation study. The thesis is organised into five chapters. A brief organization of the thesis is presented below, Chapter-1 gives the introduction on composite material and its constitutive law. The details of shear locking phenomena and the interlaminar stress distribution across the thickness is brought out and the present methods to avoid shear locking has been presented. Chapter-2 presents the different displacement based higher order shear deformation theories existing in the literature their advantages and limitations. Chapter-3 presents the formulation of a super-convergent finite element formulation, where the effect of lateral contraction is neglected. For this element static and free vibration studies are performed and the results are validated with the solution available in the open literature. Chapter-4 presents yet another super-convergent finite element formulation, wherein the higher order effects due to lateral contraction is included in the model. In addition to static and free vibration studies, wave propagation problems are solved to demonstrate its effectiveness. In all numerical examples, the super-convergent property is emphasized. Chapter-5 gives a brief summary of the total research work performed and presents further scope of research based on the current research.

Limitações de altura são frequentemente impostas à edificações de múltiplos pavimentos por regulamentos de zoneamento urbano, aspectos econômicos e considerações estéticas. Um pé-direito alto é normalmente requerido para se permitir a passagem de tubulações e dutos de grande diâmetro sob vigas de aço, conduzindo muitas vezes à alturas inaceitáveis entre pavimentos de edificações. Várias são as soluções possíveis para se resolver tal inconveniência, dentre elas pode-se citar: Vigas com inércia variável, stub girders , treliças mistas e vigas misuladas. Outra solução frequentemente utilizada é a abertura de furos na alma das vigas d e aço para a passagem das tubulações de serviço. A presente dissertação tem por objetivo avaliar e descrever o comportamento estrutural de vigas de aço com aberturas de diferentes tamanhos e formas na alma. Outro propósito deste trabalho de pesquisa é a avaliação dos parâmetros que influenciam diretamente a capacidade de resistência das vigas com diferentes tipos de abertura na alma, tais como: Tipo de furo, localização do furo ao longo do vão, altura do furo em relação à altura do perfil, esbeltez da alma, localização da carga solicitante ao longo do vão, entre outros. Também é objetivo deste trabalho, a avaliação dos diferentes mecanismos de ruína para as vigas com aberturas na alma e as causas que conduziram o colapso das mesmas. Finalmente, apresenta-se um estudo da eficácia de enrijecedores longitudinais nos locais de abertura da alma das vigas de aço. A metodologia empregada para tal estudo baseou-se em uma análise paramétrica com o auxílio do método numérico dos elementos finitos. / Height limitations are frequent in multi-storey buildings due to zoning regulations, economic requirements and esthetical considerations . In order to provide the passage of large pipes and ducts beneath steel beams, huge spaces are normally required, leading many times to unacceptable heights between storeys. There are many possible solutions to solve these problems, such as: Tapered beams, stub girders, composite trusses and haunched beams. Another frequent solution is the opening of holes in the web beam steel to enable the passage of the services. This dissertation has the objective of evaluating and describing the structural behavior of steel beams with web openings of different shapes and sizes. Another aim of this research work is the evaluation of the parameters that directly influence the load carry capacity of the beams with different web openings, such as: Holesh ape, the location of the opening throughout the span, the height hole to height profile ratio, the web slenderness and the location of the load point throughout the span. The evaluation of the different failure mechanisms of steel beams with web openings and the reasons that conducted the collapse of them are also focused on the present work. Finally, a study of the efficiency of the use of longitudinal stiffeners at web openings locations is also presented. The methodology employed for such study was based on a parametric analysis based on the finite elements method.

Limitações de altura são frequentemente impostas à edificações de múltiplos pavimentos por regulamentos de zoneamento urbano, aspectos econômicos e considerações estéticas. Um pé-direito alto é normalmente requerido para se permitir a passagem de tubulações e dutos de grande diâmetro sob vigas de aço, conduzindo muitas vezes à alturas inaceitáveis entre pavimentos de edificações. Várias são as soluções possíveis para se resolver tal inconveniência, dentre elas pode-se citar: Vigas com inércia variável, stub girders , treliças mistas e vigas misuladas. Outra solução frequentemente utilizada é a abertura de furos na alma das vigas d e aço para a passagem das tubulações de serviço. A presente dissertação tem por objetivo avaliar e descrever o comportamento estrutural de vigas de aço com aberturas de diferentes tamanhos e formas na alma. Outro propósito deste trabalho de pesquisa é a avaliação dos parâmetros que influenciam diretamente a capacidade de resistência das vigas com diferentes tipos de abertura na alma, tais como: Tipo de furo, localização do furo ao longo do vão, altura do furo em relação à altura do perfil, esbeltez da alma, localização da carga solicitante ao longo do vão, entre outros. Também é objetivo deste trabalho, a avaliação dos diferentes mecanismos de ruína para as vigas com aberturas na alma e as causas que conduziram o colapso das mesmas. Finalmente, apresenta-se um estudo da eficácia de enrijecedores longitudinais nos locais de abertura da alma das vigas de aço. A metodologia empregada para tal estudo baseou-se em uma análise paramétrica com o auxílio do método numérico dos elementos finitos. / Height limitations are frequent in multi-storey buildings due to zoning regulations, economic requirements and esthetical considerations . In order to provide the passage of large pipes and ducts beneath steel beams, huge spaces are normally required, leading many times to unacceptable heights between storeys. There are many possible solutions to solve these problems, such as: Tapered beams, stub girders, composite trusses and haunched beams. Another frequent solution is the opening of holes in the web beam steel to enable the passage of the services. This dissertation has the objective of evaluating and describing the structural behavior of steel beams with web openings of different shapes and sizes. Another aim of this research work is the evaluation of the parameters that directly influence the load carry capacity of the beams with different web openings, such as: Holesh ape, the location of the opening throughout the span, the height hole to height profile ratio, the web slenderness and the location of the load point throughout the span. The evaluation of the different failure mechanisms of steel beams with web openings and the reasons that conducted the collapse of them are also focused on the present work. Finally, a study of the efficiency of the use of longitudinal stiffeners at web openings locations is also presented. The methodology employed for such study was based on a parametric analysis based on the finite elements method.

Este trabalho objetivou o estudo dos edifícios de múltiplos andares constituídos por elementos mistos aço-concreto, com enfoque acadêmico, porém abordando aspectos e recomendações normativas diretamente aplicadas na prática corrente da engenharia estrutural. A revisão bibliográfica foi realizada com base em estudos acadêmicos e normativos além do estudo de um edifício exemplo constituído por elementos mistos. Os elementos mistos lajes, vigas e pilares foram abordados inicialmente de forma isolada, com base nas recomendações normativas, sendo que ao final os elementos foram interligados, apresentando ao leitor os principais aspectos teóricos e normativos para o dimensionamento de um edifício completo constituído de elementos estruturais mistos. / This study aims the multiple storey buildings formed by composite elements steel-concrete, with academic emphasis, however approaching standard recommendations and aspects directly applied to the structural engineering. A bibliographic review based on academic and standard studies was made, besides the design of an example building formed by composite elements. The composite elements: slabs, beams and columns were firstly approached based on standard aspects, and in the end, the elements were interconnected and presented to the reader the main theoretical and standard aspects to the design of a complete building formed by composite structural elements.

The goal of this work is to develop and demonstrate a comprehensive analysis of single and multi-body composite strip-beam systems using an asymptotically-correct geometrically nonlinear theory. The comprehensiveness refers to the two distinguishing features of this work, namely the unified framework for the analysis and the inclusion of the usually ignored cross-sectional nonlinearities in thin-beam and multi-beam analyses. The first part of this work stitches together an approach to analyse generally anisotropic composite beams. Based on geometrically exact nonlinear elasticity theory, the nonlinear 3-D beam problem splits into either a linear (conventionally considered) or nonlinear (considered in this work) 2-D analysis of the beam cross-section and a nonlinear 1-D analysis along the beam reference curve. The two sub-tasks of this work (viz. nonlinear analysis of the beam cross-section and nonlinear beam analysis) are accomplished on a single platform using an object-oriented framework. First, two established nonlinear cross-sectional analyses (numerical and analytical), both based on the Variational-Asymptotic Method (VAM), are invoked. The numerical analysis is capable of treating cross-sections of arbitrary geometry and material distributions and can capture certain nonlinear effects such as the trapeze effect. The closed-form analytical analysis is restricted to thin rectangular cross-sections for generally anisotropic composites but captures ALL cross-sectional nonlinearities, and not just the well-known Brazier and trapeze effects. Second, the well-established geometrically-exact nonlinear 1-D governing equations along the beam reference curve, after being generalized to utilize the expressions for nonlinear stiffness matrix, are solved using the mixed variational finite element method. Finally, local 3-D stress, strain and displacement fields for representative sections in the beam are recovered, based on the stress resultants from the 1-D global beam analysis. This part of the work is then validated by applying it to an initially twisted cantilevered laminated composite strip under axial force. The second part is concerned with the dynamic analysis of nonlinear multi-body systems involving elastic strip-like beams made of laminated, anisotropic composite materials using an object-oriented framework. In this work, unconditionally stable time-integration schemes presenting high-frequency numerical dissipation are used to solve the ensuing governing equations. The codes developed based on such time-integration schemes are first validated with the literature for two standard test cases: non-linear spring mass oscillator and pendulum. In order to apply the comprehensive analysis code thus developed to a multi-body system, the four-bar mechanism is chosen as an example. All component bars of the mechanism have thin rectangular cross-sections and are made of fiber reinforced laminates of various types of layups. They could, in general, be pre-twisted and/or possess initial curvature, either by design or by defect. They are linked to each other by means of revolute joints. Each component of the mechanism is modeled as a beam based on the first part of this work. Results from this analysis are compared with those available in the literature, both theoretical and experimental. The margins between the linear and non-linear results are evaluated specifically due to the cross-sectional nonlinearities and shown to vary with stacking sequences. This work thus demonstrates the importance of geometrically nonlinear cross-sectional analysis of certain composite beam-based four-bar mechanisms in predicting system dynamic characteristics. To enable graphical visualization, the behavior of the four-bar mechanism is also observed by using commercial software (I-DEAS + NASTRAN + ADAMS). Finally, the component-laminate load-carrying capacity is estimated using the Tsai-Wu-Hahn failure criterion for various layups and the same criterion is used to predict the first-ply-failure and the mechanism as a whole.