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Showing 1 to 20 of 249 for “"elementos finitos"”.
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Elementos finitos Taylorianos
A finite element model which makes use of the Taylor series to represent the displacement field, is presented. This way the interpolation functions for a domain in the periphery of the origin of the expansion in series are defined in respect to some points in the periphery of that origin. The form …
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Comparação de elementos finitos tridimensionais
Analyzed are finite three-dimensional elements. The elements studied are the hexahedron isoparametric ZIB-8 and ZIB-20, the tetrahedron TET-4, and there is formed an automatic program where the element ZIB-8 and two compositions of 12 and 24 tetrahedron, are analyzed. The presentation of the work …
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Análise de cascas espessas com elementos finitos mistos
This paper presents the development of a mixed finite element for analysis of thick shells of arbitrary shape, in the most general case. The fundamental unknowns are stresses and displacements. The analysis is linear and is based on the Theory of Elasticity. The finite element at issue is a …
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Método dos elementos finitos aplicado ao problema de escavação
Analysis of a bi-dimensional excavation using the Finite Element Method. The soil is considered to be isotropic and non-linear material, although following Hooke's law for small increments of stresses. The mechanical parameters of the soil are function of the state of stresses. A finite element …
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Análise dinâmica de placas pelo método dos elementos finitos
The main purpose of the present work is to study the dynamic behavior of plates under specified time-varying loads and moving forces. Initially a brief exposition of the variational formulation concerning the dynamics of thin plates is presented and the finite element method is applied to this …
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Análise de estabilidade elástica pelo método dos elementos finitos
Study the elastic stability of structures, using the finite elements method. In the first part it is presented an overall view of the stability criteria, and the essential differences among them. Using the criteria of the stationary value of the potential energy we have modified the method of …
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Métodos de elementos finitos mixtos con deformaciones supuestas en elastoplasticidad
… en esta tesis se encuentra en el contexto de los elementos mixtos con deformaciones supuestas en plasticidad. Empleando las formulaciones para deformaciones infinitesimales y para deformaciones finitas, que se analizan de manera crítica y detallada al principio de este trabajo se investigan …
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Ambiente para geração de modelos de elementos finitos em microcomputadores
The present work consists of an interactive graphics pre and post-processing environment for structural models discretization, plane and espatial, into finite element meshes in microcomputers. This work comes to make a contribution in the popularization of finite elements method, allowing …
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Análise de aberturas subterrâneas circulares pelo método dos elementos finitos
The present dissertation is about a two-dimensional computer program for the analysis of underground openings under plane-strain conditions. The numerical analyses are carried out by means of Finite Element Method (FEM) the quadratic isoparametric element being used. Linear and bi-linear elastic …
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Modelos mistos de elementos finitos para análise de grandes deformações
In the present work finite elasticity problems are studied through the use of an isoparametric rnixed elernent in wich stresses and displacements are approximated by the same interpolation functions. This finite element model is derived from a Reissner-type incremental variational principle based …
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Análise não-linear de estruturas laminares pelo método dos elementos finitos
ln this work, the finite element method is applied 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 …
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A análise elasto-plástica de túneis pelo método dos elementos finitos
In this paper a finite element program for the elastoplastic plane strain analysis was developed. Its purpose is to compute the displacements and stresses in soil and rock masses, and in tunnel supporting elements. Basic characteristics of other tunnel design methods have also been discussed. At …
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Elementos finitos para flexão de placas com campo de tensões assumido
The development of two Hybrid Pian's formulation of the finite element method based on assumed stress distribution and applicable to plate-bending problem is presented. The former makes use of Reissner's theory for bending of "moderately thick" plates and the latter is based on the customary theory …
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Métodos de elementos finitos e diferenças finitas para a equação de Helmholtz
Os métodos clássicos de elementos finitos e diferenças finitas, quando aplicados à equação de Helmholtz, apresentam o que é chamado de efeito de poluição do erro, comprometendo seriamente a qualidade da solução aproximada. Em virtude de numérico, foram desenvolvidos, nas últimas décadas, uma série …
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Análise estática de placas pelo método combinado elementos finitos - matriz de transferência
This work deals with the combined finite element-transfer matrix method. The main advantage of this method is to reduce the size of matrices envolved in the analysis which is useful in microcomputers with little RAM memory. Herein this method is used for static analysis of isotropic retangular …
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Análise não-linear geométrica de pórticos tridimensionais pelo Método dos Elementos Finitos
In this work, the finite element method is applied to problems involving the geometrically nonlinear behaviour of framed structures. Two consistent formulations of three-dimensional beam element are presented. In the first one, the element is straight with constant cross section and the …
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Análise de grandes deformações e plasticidade por meio de elementos finitos isoparamétricos
Through the finite element method, the non-linear behavior of problems involving large deformation and plasticity is analysed. Both for Lagrangian and Eulerian formulation, the continuous is approximated by quadratic isoparametric elements, and the analysis of plane stress, plane strain and …
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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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