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Showing 1 to 16 of 16 for “"Dinâmica das estruturas"”.
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Um algoritmo de ordem superior para a integração direta das equações da dinâmica estrutural
In this work an algorithm for the direct integration of the equation of motion of structural systems based on the cubis interpolation of the inertia forces is studied. The algorithm is conditionally stable and uses an iterative procedure. The spatial discretization is accomplished by the Finite …
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Dinâmica de estruturas prismáticas laminares - consideração de cargas móveis
Dynamic analysis of laminated structures submitted to moving loads. The formulation of the problem makes use of Hamilton's principle and the linear theory of thin plates. Associated with the Fourier series, the finite element method is used to discretize the spatial variables. The resulting system …
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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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Otimização estrutural em problemas dinâmicos
Presents an optimization structural procedure under dynamic constraints. The constraints imposed on the optimization problem can be subdivided into two classes: constraint on the natural frequency of the structure and dynamic response constraint. It is presented a general computer program for the …
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Análise de vibração de uma haste sob a ação de forca centrifuga e de Coriolis
The dynamic stability and the analysis of motion of a bar under the action of centripetal and Coriolis acceleration is investigated. A simplified one degree of freedom model is used for the cases of a rigid and a flexible bar. The equations of motion may be established by Lagrangian or Newtonian …
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Aplicação do método de Ritz extendido na análise de vibrações e estabilidade dinâmica de placas circulares
The aim of this paper is to present an appraximate soluction for the natural frequencies of circular plates, under axisynnetric transverse vibration. It was used the Ritz method to form a minimizing sequence for the energy functional. Initially a review of the basic principles of the variational …
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Análise dinâmica elasto-plástica de transiente de curta duração incluindo os efeitos da interação solo-fluido-estrutura
The finite element method is employed in the prediction of the dynamic transient response of structures systems exhibiting material non-linearity. The central difference explicit time marching schem is adopted for integration of the dynamic equilibrium equation and a diagonal lumped mass matrix is …
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Métodos de redução de base para problemas térmicos em regime transiente com condições de contorno de radiação e convecção
ln the past few years there have been a renewed interest in reduction methods for transient heat transfer analysis. Particularly, for transient heat conduction, it has been shown that reduction methods based on Lanczos-type algorithms or Ritz methods are most effective than the usual direct …
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Análise dinâmica linear de cascas axissimétricas com um elemento finito curvo
Linear dynamic analysis based on the theories of LOVE and FLÜGGE is presented for axisymmetric thin shells under the action of arbitrary loads including temperature effects. The general equilibrium equations and the corresponding boundary conditions are obtained from the Principle of Virtual work. …
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Análise dinâmica linear por superposição modal de cascas finas arbitrárias pelo Método dos Elementos Finitos
The main purpose of this work is to study the linear dynamic behavior of arbitrary thin shells by the Finite Element Method. Plane triangular elements with eighteen degrees of freedom each are used. The general equations of movement are obtained from the Hamilton Principle and solved by the Modal …
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Dinâmica de uma estrutura origâmica cilíndrica atuada por ligas com memória de forma
Origami, the art of paper folding, has been inspiration to the development of new engineering structures due to its intrinsic ability of change its shape and volume. Associated with smart materials, these structures have a great potential in the creation of self-expandable devices. Shape memory …
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Esforços hidrodinâmicos em grupos de corpos submersos
The purpose of this work is to analyse the use of the Boundary Element Method (BEM) for solving the problem defined by the forced vibration of a pair of slender circular cylinders immersed in aninfinite fluid domain. The formulation of the problem is done through the assumption of simplifying …
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Método da forma normal e suas aplicações em oscilações e estabilidade
An analytical-numerical method for the study of nonlinear systems of ordinary differential equations near an equilibrium point, especially 1n the case of a bifurcation. This method is called "Normal Form Method" (NFM) and it is based in the Normal Form Theory and Center Manifold Theory. We derive …
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Previsão do comportamento estático e dinâmico de estruturas de máquinas operatrizes
The flexibility method is formulated with an immediato application to the stitic and dynamic analysis of mochine tool structures. There is also presented a computer program for predicting from design drawings the static deformations and the natural froequencias and modes of vibration of such …
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Resposta dinâmica de estruturas reticuladas a cargas móveis, pelo método dos elementos finitos
Studies the dynamic behavior of framed structures under moving loads by means of the finite element method. Three different types of loadings are idealized and impact factors determined for them, being developed computer programs for dynamic analysis of beams and plane frames. The structure-loading …
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Uma formalização da mecânica analítica dos sistemas de corpos rígidos
The Lagrange's equations for systems of rigid bodies are obtained directly from the laws of motion for a rigid body, without the preliminary study of systems with a finite number of parti eles. ln doing so, the role of the evolution law for the angular momentum is made clear for the development of …