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Showing 1 to 13 of 13 for “"Análise não-linear de estruturas"”.
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Análise não-linear de estruturas reticuladas espaciais de concreto armado
Present an automatic program for non-linear analysis of spacial frames of reinforced concrete, including verification of structures under definite loading and research on its load-bearing capacity for a given disposition of loads. On its development are considered both the non-linearity of the …
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Análise não-linear de estruturas laminares pelo método dos elementos finitos
… to problems involving the geometrically non-linear behaviour of surface structures, subjected to static and dynamic loads. Two kinds of formulations are studied. ln the first one, through isoparametric degenerated elements, the tridimensional theory of elasticity is directly used. There are …
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Análise não-linear de estruturas de concreto armado submetido ao estado plano de tensões
… remanescentes da Engenharia Estrutural é a análise de estruturas de concreto armado que rompem ao cisalhamento. Isto se deve ao fato de um comportamento bastante complexo, envolvendo diversos mecanismos internos como, fissuração do concreto e transmissão dos esforços de cisalhamento através …
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Um modelo numerico para analise de estruturas de materiais compostos considerando efeitos viscoelasticos e falhas progressivas
Neste trabalho apresentam-se pocedimentos para análise não linear de estruturas de materiais compostos laminados reforçados por fibras. A formulação é baseada em uma descrição cinemática incremental Lagrangeana Total, que permite o tratamento de deslocamentos arbitrariamente grandes com pequenas …
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Formulações e métodos de solução na análise não-linear de treliças espaciais
… formulations for geometrically and materially nonlinear analysis of space trusses, and the most commonly used nonlinear equation solution algorithms. These formulations, and two others; are implemented in the ANALITE program. The Total Lagrangean and Updated Lagrangean formulations are developed …
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Implementação do cálculo do Fator de Cholesky diretamente a partir da matriz de rigidez do elemento estrutural
… The results from the computers program which was developed for the new method have garanteed its precision and the advantage of employing it to solve ill-conditioned problems. The basic ideas of this formulation were developed in Germany by other authors for the ASKA system. These ideas have been …
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Um método interativo para análise de não-linearidade geométrica em estruturas reticulares
An iteration procedure is presented to determine the buckling loads of plane and space framed structures taking into account non-linear behavior. Two effects are included in the analysis: the axial forces on the member stiffness matrix and the changes of geometry caused by large displacements. A …
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Análise do comportamento não linear geométrico e físico de pórticos planos de concreto armado
… plane frames, where two different types of non linearities are dealt with: 1) Geometrical non linearity: considering the second-order effects, resulting from axial-flexural interaction; 2) Physical non linearity: considering the physical characteristics of materials (concrete and steel), through …
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Aplicação de controle preditivo não linear multivariável com otimizador à operação transiente de turbina a gás
Apply and to investigate a multivariable nonlinear modelbased predictive control strategy to avoid unsafe or inappropriate operation of a gas turbine. In this research, the controller maintains the rotational speed of the compressor constant in accordance with the grid frequency, during load …
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Estruturas tridimensionais com propriedades mecânicas dos materiais representadas matematicamente por séries - aplicação à análise de pontes
… cross section. The analysis allows the consideration of diaphragms. The mechanical properties are expanded into FOURIER series, allowing for variations in the material and geometric characteristics of the structure. Besides the mechanical properties, all the other dependent variables are also …
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Uma formalização da mecânica analítica dos sistemas de corpos rígidos
… the evolution law for the angular momentum is made clear for the development of the theory. We obtain Euler's equation for a rigid body with a fixed point from Lagrange's equations, without using Euler's angles. And an elementary proof for the velocity field of a rigid body moving with a fixed …
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Monitoração de sistemas mecânicos pela assinatura decrescimento aleatório
The applicability of the "Random Decrement Function" to the detection of failures in linear mechanical systems is studied together with its sensitivity to the variations of measurement parameter such as, accelerometer position, frequency range, threshold level, number of samples. A continuous …
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Análise não-linear e simulações de oscilações de sub-vão em linhas de transmissão
The majority of the published research used a linearized version of the mathematical model describing the dynamics of sub-span oscillations. The problem was always reduced to a flütter-problem. A definition for the amplitude of the limit cycle and its stability were not possible using this …