EM - Escola de Minas
URI permanente desta comunidadehttp://www.hml.repositorio.ufop.br/handle/123456789/6
Notícias
A Escola de Minas de Ouro Preto foi fundada pelo cientista Claude Henri Gorceix e inaugurada em 12 de outubro de 1876.
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3 resultados
Resultados da Pesquisa
Item Análise numérica do comportamento não linear de estruturas mistas de aço e concreto.(2017) Lemes, Igor José Mendes; Silva, Andréa Regina Dias da; Silveira, Ricardo Azoubel da Mota; Rocha, Paulo Anderson SantanaO presente trabalho apresenta o desenvolvimento de uma formulação numérica adequada para análise de estruturas mistas de aço e concreto considerando os efeitos da não linearidade geométrica e da inelasticidade dos materiais. Para tal, foi desenvolvida uma metodologia baseada no Método da Rótula Plástica Refinado (MRPR), sendo os coeficientes de rigidez obtidos por meio da homogeneização da seção transversal. A avaliação da capacidade resistente dos elementos estruturais é feita no contexto do Método da Compatibilidade de Deformações (MCD). Os problemas oriundos da consideração das fontes de não linearidade (global e local) são resolvidos por meio do método iterativo de Newton- -Raphson acoplado a estratégias de continuação. Os resultados obtidos são comparados com aqueles fornecidos em análises experimentais e/ ou numéricas presentes na literatura, sendo verificada boa precisão nas análises de seções transversais mistas, pilares isolados mistos e pórticos simples mistos.Item Nonlinear analysis of two-dimensional steel, reinforced concrete and composite steel-concrete structures via coupling SCM/RPHM.(2017) Lemes, Igor José Mendes; Silveira, Ricardo Azoubel da Mota; Silva, Andréa Regina Dias da; Castro, Paulo de Tarso AmorimThis paper presents a numerical methodology based on Euler-Bernoulli theory to simulate the steel, reinforced concrete and composite structures 2D nonlinear behavior. The displacement-based numerical formulation uses the principles of the Refined Plastic Hinge Method (RPHM) to simulate the concentrated plasticity at the corotational finite element nodal points. In order to present a more realistic simulation of the axial and flexural stiffness degradation, the RPHM is coupled with the Strain Compatibility Method (SCM), where the materials constitutive relations are used explicitly. The SCM is also applied in determining the structural elements’ bearing capacity. Moreover, the present approach is not limited to a specific cross-sectional typology. Also addressed are residual stress models; these are introduced explicitly in subareas of steel profiles generated by a two-dimensional cross-sectional discretization. It should be emphasized that this study considers full interaction between the materials. Finally, the results obtained are compared with numerical and experimental findings available in the literature.Item Nonlinear equilibrium and stability analysis of axially loaded piles under bilateral contact constraints.(2015) Silveira, Ricardo Azoubel da Mota; Maciel, Felipe Vieira; Silva, Andréa Regina Dias da; Machado, Fernando Carlos Scheffer; Nogueira, Christianne de LyraThis paper presents a nonlinear stability analysis of piles under bilateral contact constraints imposed by a geological medium (soil or rock). To solve this contact problem, the paper proposes a general numerical methodology, based on the finite element meth-od (FEM). In this context, a geometrically nonlinear beam-column element is used to model the pile while the geological medium can be idealized as discrete (spring) or continuum (Winkler and Pas-ternak) foundation elements. Foundation elements are supposed to react under tension and compression, so during the deformation process the structural elements are subjected to bilateral contact constraints. The errors along the equilibrium paths are minimized and the convoluted nonlinear equilibrium paths are made tracea-ble through the use of an updated Lagrangian formulation and a Newton-Raphson scheme working with the generalized displace-ment technique. The study offers stability analyses of three prob-lems involving piles under bilateral contact constraints. The anal-yses show that in the evaluation of critical loads a great influence is wielded by the instability modes. Also, the structural system stiffness can be highly influenced by the representative model of the soil.