Comportamento estrutural de lajes pré-moldadas treliçadas com adição de resíduos de borracha de pneu

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Estudo de lajes com adição de resíduo de pneu

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Estudo da eficiência de reforços estruturais em vigas de concreto armado com o uso de chapas de aço coladas com resina epóxi: uma análise qualitativa

In civil engineering, a structure is the whole sustainment of a construction and, thus, it is important that it remains intact throughout its lifetime. An engineering construction must last for decades without losing its functionality. However its purpose may be altered and several times the original structure does not meet the new needs of use. Still, in new buildings, the functionality is altered due to possible flaws in execution and the structure, invariably does not reach the desired solicitation needs. In cases like this, the commonly adopted solutions are, basically, the demolishment followed by the reconstruction of the desired mold or the structural reinforcement. This second option, for long years, has not been put to practice due to certain factors such as the high costs for its implantation, use of inadequate reinforcement execution techniques, and the culture of people involved in the area regarding its use and, in this case, the option would always be the reconstruction. Thoughtout the years, some techniques were developed to allow the execution of structural reinforcements with low costs and in efficient ways. An interesting, fast, efficient and economical technique is the structural reinforcement through metal sheets put together with epoxy resin that can be applied in beams, slabs and pillars. In the present work the different behavior of beams reinforced with this technique. Steel is a very recommended material for these reinforcements due to its characteristics related to traction, compression and the effectiveness of the technique related to its cost. For the attachment the epoxy resin is recommended, since it allows the joining of two materials, in this case, steel and concrete. The efficiency of this union is so considerably high that it rarely produces any flaws in adherence and, normally, when it happens it is due to problems in the execution process, not in the union of materials

Passado e presente nas relações Colômbia-Estados Unidos: a estratégia de internacionalização do conflito armado colombiano e as diretrizes da política externa norte-americana

Este artigo tem como objetivo analisar a dinâmica das relações entre Colômbia e EUA, com ênfase no governo de Álvaro Uribe (2002-...). Para tanto, são examinadas a estratégia de internacionalização do conflito armado colombiano e os aspectos da intervenção dos EUA mediante o Plano Colômbia. Como conclusão, o trabalho sugere que as recentes mudanças políticas nos EUA têm causado impacto nas diretrizes das relações das relações entre EUA e Colômbia.

Dependência estrutural da capacidade de rotação plástic em vigas de concreto armado

Summary In this work the structural dependence of plastic rotation capacity in RC beams is evaluated using the Finite Element Method. The objective is to achieve a better understanding of the non-linear behavior of reinforced concrete members and perform extensive parameter studies, using a rational model developed by Bigaj [1] to analyze the phenomenon of plastic rotation capacity in reinforced concrete members. It is assumed that only bending failure is relevant due to sufficient member resistance against shear and torsion. The paper begins with the physical and theoretical background of the phenomenon of plastic hinge development in RC structures. Special emphasis is laid on the issue of structural dependence of deformation capacity of plastic hinges in RC members. Member size dependence and influence of properties of construction materials were emphasized as well. The essential components of the Bigajs model for calculating the plastic rotation capacity are discussed. The behaviour of the plastic hinge is analysed taking into account the strain localisation in the damage zones of the hinge region. The Fictitious Crack Model (FCM) and the Compressive Damage Zone Model (CDZ) are adopted in a Fracture Mechanics approach to model the behaviour of concrete in tension and compression, respectively. The approach is implemented in FEMOOP, a FEM in-house solver under development, and applied to evaluate ductility in 2D beams. The models were generated with GiD, a pre-processor and post-processor developed by CIMNE, and analyzed with the capabilities implemented in FEMOOP. © Universitat Politècnica de Catalunya, Barcelona, España 2010.

Análise numérica de lajes treliçadas pré-moldadas com adição de resíduo de borracha

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Análise não-linear física de vigas de concreto armado utilizando o elemento finito prismático regular linear associado ao de barra

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Análise numérica da ductilidade de vigas de concreto armado convencional e de alto desempenho

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

O cidadão armado comunismo e tenentismo (1927-1945)

Pós-graduação em História - FCHS

Dimensionamento e análise numérica de cascas de concreto armado para aplicações em plataformas offshore

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Determinação dos esforços em lajes pelo métodos dos elementos de contorno

Through deductions and formulations of the equations governing the behavior of plates elastic and thin based Kirchhoff theory, it is evident that it is justifiable to the complication of the numerical methods considering the complexity of the equations that describe the physical behavior of these elements and obtaining analytical solutions for specific situations. This study is directed to the application of the numerical method which is based on discretizations to the simplest elements which results in the reduction of data to be processed from. The numerical method in question is the Boundary Element Methods (BEM), as the name suggests, the discretizations are only the edges of the elements. The BEM converts the complex integral equations, in sums of functions that reduce the unknowns at the nodes that define the ends of discrete elements, obtaining internal values to elements using interpolation functions. Confirming the need and usefulness of the BEM, apply, then the foundations necessary to the specific cases of Civil Engineering where traditional methods do not provide the desired support, leaving in question the security situations and economics of the projects

Verificação de terceira ordem de estruturas de concreto armado de edíficios

The change in design of a building can occur during its construction process, especially when this change involves greater amount of profit for the building company, as it is the case of adding extra floors. However, there must be an analysis of the structure of the building in order to see if it is possible to increase the number of floors without the need of reinforcement, as this need would result in higher costs for the building company. This graduation report presents this analysis by using the methods of third order verification of reinforced concrete structures

Controle de qualidade em estruturas na construção civil

This work is to control the quality of the structures, procedures for addressing the assembly of the formwork, scaffolding and the frame of pillars, beams and slabs. He had also intended to show that the vibration of launch and concrete items are also important, if poorly implemented can undermine the structure. This work also shows that the mapping becomes essential if there is some problem in the concrete, where concrete was launched, could be identified. And finally check the product where the structure will be evaluated for how much their quality

Avaliação de momentos fletores em estruturas de fundação tipo radier em concreto armado

It aims the comparison of these moments between an analytical plates theory and a computational numerical simulation. It is accented the details of studies about analytical theory as well the process, step by step, of a program that has as an influence the method of finite elements. The theory of plates has an extremely importance when it is talked about slabs and it takes as a base some fundamental hypotheses (that the middle point of the plate is considered flat and under formable) the points that are normal in relation to the middle surface is not considered because of its intensity that is irrelevant in comparison to the rest. The computational programs offer good results when they are applied in a correct way and, it resolves numerous functions in a short period of time. The objective is to highlight the importance of bending moments, its points of maximum and minimum, that has the objective of realize a good reinforcement sizing for a reinforced concrete. Furthermore, it can propitiate an economy in places that is demanded a small quantity of steel, before dimensioned for a load that is distributed in all the surface of the plate, at the same intensity

Qualidade da construção civil de estrutura de concreto armado, alvenaria de vedação e revestimento externo de obras verticais

The main purpose of this research is to raise, through lab rehearsals, the geometric properties of some oxisols from the region of Vale do Paraíba as well as comparing them to demands prescribed by Technical Specifications ESP08/05 of the Road Department of the State of Paraná, for sub-base or fine grained lateritic soil base (SAFL) and in the Technical Specification ET-DEP00/006 of the Road Department of the State of São Paulo (DER/SP) for subbase or crushed stone base. According to the results that were obtained it will be feasible to appraise the usage of these sorts of soils in structure layers of low-weight traffic pavements