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Showing 1 to 20 of 84 for “"Vigas"”.
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Análise dinâmica de vigas de pontes pelo método dos elementos finitos - aplicação a vigas Gerber
The dynamic analysis of bridges is presented, being the bridge idealized as an elastic beam under the action of moving constant forces. Special emphasis is given to the dynamic behavior of cantilever bridges. The structure is discretized in finite elements and the analysis is conducted by means of …
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Análise dinâmica das vigas sandwich comprimidas
The problem undertaken is this work is to determine and analyze the equations of lateral vibrations of sandwich beams with an axial compressive load, as well as the analysis of the instability loads by a dynamic method. Some cases, corresponding to several boundary conditions, were studied and the …
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Verificação experimental de vibrações paramétricas em vigas
Experimental investigation of parametric resonance of a bar subjected to an axial compressive force P, smaller than the buckling load and to an oscillating torque of the type T = T₀ + T₁1 cos Ω t, , where T₀, T₁ e Ω are independent pameters. The regions of elastodynamic instability are determined …
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Integridad estructural de vigas roblonadas de acero estructural antiguo
… la evaluación de la integridad estructural de vigas roblonadas antiguas que tiene en cuenta la interacción entre componentes. Una de sus contribuciones es el desarrollo de un método analítico para el cálculo del factor de intensidad de tensiones en vigas común componente fisurado. La …
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Modos em vigas com secção transversal de variação linear
… obtenção dos modos e as freqüências naturais de vigas de variação linear e em forma de cunha, com condições de contorno clássicas e não-clássicas, descritas pelo modelo estrutural de Euler-Bernoulli. A forma dos modos foi determinado com o uso das funções cilíndricas. No caso forçado se considera …
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Avaliação da confiabilidade de vigas otimizadas de concreto armado
No projeto de vigas de concreto armado, o procedimento padrão constitui em estimar as dimensões da seção transversal, determinar as armaduras através das equações de equilíbrio estático e realizar as verificações de segurança e utilização. Caso os critérios sejam atendidos, o dimensionamento é …
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Cortante longitudinal em vigas de concreto com mesas comprimidas
This work consists of an experimental study about the longitudinal shear problem in beams of reinforced concrete with compression flanges. It is included a brief summary of the design methods and tests published earlier, and also the recommendations of some codes of practice related to the subject. …
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Tensões locais em vigas de rolamento de instalações siderúrgicas
This work deals with the determination of local stress in steel crane runway girders of mill instalations. Herein an state of the art is presented about the execution details which can cause fadigue cracks due to the local effects in the upper part of the crane runway girders. A computer program is …
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Estudo da flexão em vigas de concreto leve armado
The subject of this dissertation deals with the bending analysis of light. Our final aim is to compare the experimental results with the CEB-FIP standards for this type of concrete. Twelve specimens were tested. All the beams tested were casted with the same geometry and dimensions, only the …
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Mecanismos de respuesta frente al esfuerzo cortante en vigas prefabricadas
… de esta tesis. En estos ensayos la rotura de las vigas prefabricadas se produjo directamente en las bielas de crotante, sin plastificación previa de los cercos. Se ha desarrollado un modelo racional en el que se combina la resistencia frente al esfuerzo cortante a través del mecanismo de la …
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Vigas contínuas em hastes de paredes delgadas: estudo da torção
This is a thesis, divided in six Chapters, that studies torsion in thin walled beams. In Chapter I, the necessary concepts to the development of the thesis are exposed: Bimoment and warpihg torsion, sectorial properties of a section. In Chapter II, an analytical study of bimoment is presented: the …
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Apoios em dente de vigas de concreto leve armado e protendido
Tests on twenty half-joints (tooth-shaped end of a beam) of ten ligthtweight concrete beams were carried out. Five were reinforced concrete beams and five prestressed concrete beams. Five different joint reinforcement details were tested. The joints were reinforced so that reinforcement yielding …
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Influência das bainhas na resistência das almas das vigas de concreto protendido
CEB Recommendations preconize that in case of verification of the web strength of the prestressed concrete bearns against the shear force, it might be taken into account the effective web thickness (by deduction of the half sum of the ducts diameters) in the considered region (bwef = bw - 1/2 ∑Ф). …
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Análise não-linear física de vigas contínuas em concreto armado e protendido
A non-linear analysis is developed for a prestressed concrete continuous beam, based on the theory of the finite-element method. As a consequence of the theoretical study, a computer program in FORTRAN is developed. This program performs a physical non - linear analysis of a prestressed continuous …
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Análise estática e dinâmica de vigas sandwich pelo método dos elementos finitos
In view of the static and dynamic analysis of sandwich beams submitted to axial loads as well as for the determination of instability critical loads the Finite Element Method has been used in the present work. The developed elements are also applied to beams where the shear strain has been taken …
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Método dos elementos finitos aplicado a análise não linear de vigas Timoshenko-Vlasov
… Finitos aplicado a análise não-linear de vigas Timoshenko-Vlasov. A princípio, objetiva-se investigar a formulação não linear tridimensional de vigas para simular estruturas reticuladas, considerando efeitos de empenamento da seção transversal como uma das variáveis do problema. Será …
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Estudo da flexão em vigas de alvenaria armada de tijolo vazado de barro
Studying the pure bending in reinforced masonry beams made with hollow clay bricks. With this aim fifteen beams with approximately the same geometrical characteristics and the same transversal reinforcement were tested until the failure. The variable parameters were the type of brick, the …
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Resistência ao esforço cortante em vigas curtas de concreto leve, sem armadura transversal
In the failure test of a reinforced concrete beam, with the loads and reactions applied on the top and bottom of the beam, respectively (named "directly loaded beam"), it is evident that the shear strenght of the beam is greatly affected by the ratio of shear span to effective depth, a/d. Thus, for …
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