Página 1 dos resultados de 206 itens digitais encontrados em 0.004 segundos

Avaliação do comportamento do concreto com adição de borracha obtida a partir da reciclagem de pneus com aplicação em placas pré-moldadas

Santos, Antonio Carlos dos
Fonte: Universidade Federal de Alagoas; BR; Estruturas; Programa de Pós-Graduação em Engenharia Civil; UFAL Publicador: Universidade Federal de Alagoas; BR; Estruturas; Programa de Pós-Graduação em Engenharia Civil; UFAL
Tipo: Dissertação Formato: application/pdf
Português
Relevância na Pesquisa
936.1623%
It was observed that the concrete is the most consumed material in the civil construction and not always satisfies all the demanded properties, its takes to researches that tries materials that can provide to the concrete more efficiency. This work, the discarding of residues procedures from the recycling of tires is focused, with the purpose to give to this material a rational destination, in the environment of the Civil Construction. The aim is to study the concrete behavior produced with rubber tire fiber addition, obtained by recycling of tire, and apply it on the confection of plates for to analyze the mechanical efforts behavior. The amongst of the additions are done in amongst usual for staple fibers. The bibliographical review disclosed that a reduction of the compressive strength when the rubber additions occurs. On the other hand, an increase of the ductility and the resistance for the impact occurs. The point of glow of the observed rubber was studied and it was observed that it occurs in a temperature range above of that one where the concrete has its deficit properties. With the short rubber fiber addition the same losses foreseen in literature without significant profits in the ductility are still verified. The rubber fibers chosen had been with low a relation length-diameter. This type for representing a small parcel and knowing that its separation can to add values that do not compensate its use as residue. Thus...

Análise da interação solo-estrutura através do emprego conjunto dos métodos dos elementos de contorno e elementos finitos; Soil-structure interaction analysis by the coupling of Boundary Element Method (BEM) and Finite Element Method (FEM)

Cavalcanti, Daniel Jatobá de Holanda
Fonte: Universidade Federal de Alagoas; BR; Estruturas; Programa de Pós-Graduação em Engenharia Civil; UFAL Publicador: Universidade Federal de Alagoas; BR; Estruturas; Programa de Pós-Graduação em Engenharia Civil; UFAL
Tipo: Dissertação Formato: application/pdf
Português
Relevância na Pesquisa
937.33516%
In this work, it is proposed a mechanical behavior analysis of the soil-structure interaction from the development of a computational code using a coupling static formulation of Boundary Element Method (BEM) and Finite Element Method (FEM) for the displacements and stress calculation in structures in contact to the half space. Thus, it is intended to model the structure using the bending plate finite element DKT (discrete Kirchhoff triangle) and applying the concepts of the Boundary Element Method (BEM) formulation to model the soil, considered as a half- infinite and/or infinite space and using Kelvin s fundamental solution. The coupling between the media is done using the sub-regions technique. From the computational code development some practical examples of engineering are implemented, such as: soil-structure interaction analysis in superficial and buried plate foundations and others engineering structures, study on the behavior of a half- infinite space from the application of a distributed and concentrated load, analysis of bodies submitted to bend and traction, among others applications.; Fundação de Amparo a Pesquisa do Estado de Alagoas; Neste trabalho, propõe-se a análise do comportamento mecânico da interação solo -estrutura a partir do desenvolvimento de um código computacional utilizando-se uma formulação estática conjunta do Método dos Elementos de Contorno (MEC) e do Método dos Elementos Finitos (MEF) para o cálculo de deslocamentos e tensões em estruturas em contato com o meio semiinfinito. Assim sendo...

Estudo de algoritmos de integração elemento por elemento para análise dinâmica não linear de estruturas

Vieira, Luciana Correia Laurindo Martins
Fonte: Universidade Federal de Alagoas; BR; Estruturas; Programa de Pós-Graduação em Engenharia Civil; UFAL Publicador: Universidade Federal de Alagoas; BR; Estruturas; Programa de Pós-Graduação em Engenharia Civil; UFAL
Tipo: Dissertação Formato: application/pdf
Português
Relevância na Pesquisa
934.8259%
The topic of structural dynamics involves an ample actuation field since the most of nature actions are time dependent. The analyses of structures in aerospace engineering, offshore engineering, civil engineering and others might be realized including the inertial effects since they have important role in reliability and safety of them. Due to the various nonlinearities that can be present in the dynamic analysis, the preview of the dynamic behavior of a structure can become a complex task. That analysis is generally executed using computational numeric algorithms improved for spatial and temporal discretization where computational requirements are excessive. Techniques based on element-by-element concept have gained recognition due to its increasing efficiency caused by the recent development of parallel computers. This work is focused on time integration algorithms for nonlinear dynamic problems formulated by the finite element approach. Besides, the considered algorithms have been prepared to be used, in the future, on parallel computational architectures. The main algorithms for nonlinear structural dynamics and alternatives of implementation of the element-by-element techniques are studied. The software MATLAB has been used for implementation of some algorithms...

Uma metodologia para o tratamento de problemas da mecânica dos sólidos com redefinição de domínio utilizando a técnica de relaxação dinâmica

Silva, Rodrigo Mero Sarmento da
Fonte: Universidade Federal de Alagoas; BR; Estruturas; Programa de Pós-Graduação em Engenharia Civil; UFAL Publicador: Universidade Federal de Alagoas; BR; Estruturas; Programa de Pós-Graduação em Engenharia Civil; UFAL
Tipo: Dissertação Formato: application/pdf
Português
Relevância na Pesquisa
934.6834%
Diverse construction work of engineering involves the execution of excavation and embankments, such as the construction of foundations, dams and urban infrastructure. In general, geomechanical problems have a high degree of complexity due to the difficulty on the parameters quantification, the definition of representative models of the soil and the interaction soil-structure. Many models are based on the final arrangement of the system, not considering the intermediate analyses that are important steps in the study of those problems. In this study was developed a methodology for modeling problems that need redefinitions of analysis domain in function of the consideration of excavations and embankments, using an alternative technique for solution of the balance equations, the Dynamic Relaxation, combined with the Finite Element Methods for the development of the model.; Fundação de Amparo a Pesquisa do Estado de Alagoas; Diversas obras de engenharia envolvem a execução de escavações e aterros, a exemplo da construção de fundações, barragens e infra-estrutura urbana. De um modo geral, a modelagem desses tipos de problemas possui um grau de complexidade alto devido à dificuldade da quantificação de parâmetros, de definição dos modelos representativos do solo e da interação solo-estrutura. Muitas modelagens baseiam-se no arranjo final do sistema...

Um elemento finito de tubo tridimensional para análise geometricamente não linear de dutos; A threedimensional pipe finite element for geometric nonlenear analyses

Machado, Alexandre Cunha
Fonte: Universidade Federal de Alagoas; BR; Estruturas; Programa de Pós-Graduação em Engenharia Civil; UFAL Publicador: Universidade Federal de Alagoas; BR; Estruturas; Programa de Pós-Graduação em Engenharia Civil; UFAL
Tipo: Dissertação Formato: application/pdf
Português
Relevância na Pesquisa
1039.13484%
In transport of fluids or even as structural elements, cylindrical shells are widely used in several segments of structure engineering. The understanding of the behavior of this type of structure along a trajectory of equilibrium resultant of a description of historical loading of different natures and, consequently, is important in the definition of the real load capacity of the ducts. In this work, a finite element for geometric and threedimensional nonlinear analyses of pipes is developed. Taking into account the nature of the analysis, proper measure of tension and deformation that are compatible with states of large deformations and displacements are studied. The Total Lagrangean formulation is adopted, but the constitutive relationships used are linear. The developed computational implementation uses a three-dimensional finite element of pipe with 2 or 3 nodes, compatible with the state of great deformations and displacements, and, also, incorporating the movements of rigid body of the structure.In order to map the nonlinear trajectories of equilibrium, using some methodologies proposed in the literature, a structure of Object-Oriented Programming is used. It allows the application of different techniques of incremental and iterative analysis integrated to the implementation of the aforementioned finite elements.Aiming to validate the formulation...

Subsídios para o projeto de estruturas sismo resistentes

Dantas, Raul Omar de Oliveira
Fonte: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Engenharia Civil; MECÂNICA DAS ESTRUTURAS, ESTRUTURAS DE CONCRETO E ALVENARIA E MATERIAIS E PROCESSOS CONSTRUTIVOS Publicador: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Engenharia Civil; MECÂNICA DAS ESTRUTURAS, ESTRUTURAS DE CONCRETO E ALVENARIA E MATERIAIS E PROCESSOS CONSTRUTIVOS
Tipo: Dissertação Formato: application/pdf
Português
Relevância na Pesquisa
934.6834%
Through this research is detailed the Brazilian seismic code focused on concrete projects design related to seismic engineering. At the beginning of the research is debated the fundaments of the seismic effects, the influence factors to the development of seismic effects and also relates the main data registration happened in Brazil. The second step is study the Brazilian seismic code explaining all the concepts related to it and does a compilation to the most important international seismic code. At this research is developed the designing of a building submitted to horizontal equivalent seismic forces and the modal process based on the answer spectrum based on the brazilin seismic code. It was also developed the design of a commercial building submitted to seismic loads based on the Brazilian code answer spectrum and compared to the same building submitted to wind loads.The research also focus on projects conception and detailing of seismic engineering Project design. At the study of seismic engineering it was concluded that seismic effects require special focus on concrete structures design, proving that is the essential consider the seismic effects; Nesse trabalho são apresentados e discutidos diversos critérios da norma NBR 15421:2006 para o desenvolvimento de um projeto de estruturas de concreto...

Avaliação do concreto de cimento portland com resíduo da produção de scheelita em substituição ao agregado miúdo

Paiva, Emanuel Henrique Gomes
Fonte: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Engenharia Civil; MECÂNICA DAS ESTRUTURAS, ESTRUTURAS DE CONCRETO E ALVENARIA E MATERIAIS E PROCESSOS CONSTRUTIVOS Publicador: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Engenharia Civil; MECÂNICA DAS ESTRUTURAS, ESTRUTURAS DE CONCRETO E ALVENARIA E MATERIAIS E PROCESSOS CONSTRUTIVOS
Tipo: Dissertação Formato: application/pdf
Português
Relevância na Pesquisa
937.5653%
From the 70`s, with the publication of the Manifesto for Environment UN Conference, held in Stockholm, in Sweden (1972), defend and improve the environment became part of our daily lives. Thus, several studies have emerged in several segments in order to reuse the waste. Some examples of waste incorporated in portland cement concrete are: rice husk ash, bagasse ash of cane sugar, powder-stone, microsilica, tire rubber, among others. This research used the residue of the mining industry Scheelite, to evaluate the incorporation of the residue composition of Portland cement concrete, replacing the natural sand. The percentage of residue were incorporated from 0% to 100%, with a variation of 10%, 11 being produced concrete mix in the ratio 1:2:3:0.60, by mass. We evaluated the following characteristics of concrete: slump test, compressive strength, tensile strength by diametral compression, water absorption, porosity and density, based on the ABNT, through tests performed in the Laboratory of Civil Construction, UFRN. The trace with the addition of 60% scheelite residue was obtained which better performance. Therefore, the use of the waste from the production of Scheelite is feasible due to the durability parameters (water absorption and porosity)...

Metodologia de implantação da construção enxuta: estudo de caso em construtora de porte médio

Oliveira, Erikson Ricardo Marques de
Fonte: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Engenharia Civil; MECÂNICA DAS ESTRUTURAS, ESTRUTURAS DE CONCRETO E ALVENARIA E MATERIAIS E PROCESSOS CONSTRUTIVOS Publicador: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Engenharia Civil; MECÂNICA DAS ESTRUTURAS, ESTRUTURAS DE CONCRETO E ALVENARIA E MATERIAIS E PROCESSOS CONSTRUTIVOS
Tipo: Dissertação Formato: application/pdf
Português
Relevância na Pesquisa
943.59125%
In recent years, the Brazilian construction industry has gone by changes like currency stability, increasing competition, shortage of skilled labor and increasing quality importance required by the customer, who made the sector companies seek solutions through new management practices in order to become more efficient. A alternative to these management practices is known as Lean Construction which is derived from the Toyota System Production. Lean Construction main goals are to reduce parts of activities that do not add value, increase product value by considering customer needs, reduce variability and production cycle time, simplify process by reducing the number of parts or steps, increase the flexibility in the product execution and transparency process, focus the control on overall process, introduce continuous improvement process, maintain a balance between improvements in flows and conversions and seek to learn from practices adopted by competitors. However, the construction industry is characterized by having nomadic activity, which undertakes an unique product with high cost of production and big inertia for behavioral change, making it difficult to implement the philosophy of lean construction in companies. In this sense, the main objective of this study is to develop a methodology for implementation of the principles of Lean Construction. The method of implementing the proposed management system was designed with the aid of 5W2H tool...

Desenvolvimento de um sistema de planejamento, gestão de serviços e controle de custos em obras de construção civil

Bezerra, João Sergio Simões
Fonte: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Engenharia Civil; MECÂNICA DAS ESTRUTURAS, ESTRUTURAS DE CONCRETO E ALVENARIA E MATERIAIS E PROCESSOS CONSTRUTIVOS Publicador: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Engenharia Civil; MECÂNICA DAS ESTRUTURAS, ESTRUTURAS DE CONCRETO E ALVENARIA E MATERIAIS E PROCESSOS CONSTRUTIVOS
Tipo: Dissertação Formato: application/pdf
Português
Relevância na Pesquisa
1039.4209%
The increasing competitiveness of the construction industry, set in an economic environment in which the offer is now greater than the demand , causes the prices of many products and services, are strongly influenced by the processes of production and the final consumer. Thus, to become more competitive in the market and construction companies are seeking new alternatives to reduce and control costs, production processes and tools that allow for close monitoring of the construction schedule, with the consequent compliance deadline with the client. Based on this scenario, the creation of control tools, service management and planning work emerges as an investment opportunity and an area that can promote great benefits to construction companies. The goal of this work is to present a system of planning, service management and costs control that through worksheets provide information relating to the production phase of the work, allowing the visualization of possible irregularities in the planning and cost of the enterprise, enabling the company to take steps to achieve the goals of the enterprise in question, and correct them when necessary. The developed system has been used in a piece of real estate in Rio Grande do Norte, and the results showed that its use together allowed the construction company to accompany their results and take corrective and preventive actions during the production process...

Estudo da viabilidade da utilização de cinza de lodo de esgoto como adição em argamassa de cimento Portland; Feasibility study of the use of sewage sludge ash as addition in Portland cement mortar

Costa, Felipe Murilo Silva da
Fonte: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Engenharia Civil; MECÂNICA DAS ESTRUTURAS, ESTRUTURAS DE CONCRETO E ALVENARIA E MATERIAIS E PROCESSOS CONSTRUTIVOS Publicador: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Engenharia Civil; MECÂNICA DAS ESTRUTURAS, ESTRUTURAS DE CONCRETO E ALVENARIA E MATERIAIS E PROCESSOS CONSTRUTIVOS
Tipo: Dissertação Formato: application/pdf
Português
Relevância na Pesquisa
937.656%
The use of sewage sludge as a raw material falls within the waste recycling key in the current process model environmental sustainability .Waste recycling has been consolidated as a sustainable environmentally sound technical solution, and. Despite showing very variable composition and characteristics, sewage sludge, can be considered as a residue with a high recycling potential in the building sector. In this paper the feasibility of using sewage sludge ash was studied in addition to Portland cement mortar in 1:3 mass considered the standard dash. This gray additions were studied in proportions of 5%, 10 %, 15 %, 20 %, 25% and 30% by mass of cement. The methodology was focused on the characterization of materials by physical, chemical , mechanical , environmental and morphological followed by the production of mortar tests ,and finalized by the characterization tests of mortar in the fresh state, through the consistency index, content of entrained air, bulk density and water retention, and in the hardened state by bulk density, water absorption by capillarity capillarity coefficient, compressive strength, tensile strength in bending ,tensile bond strength and microstructural analysis for percentages of 0 to 20%. After comparing with the standard mortar mortars with addition of ash...

Análise numérica do efeito de fatores influentes da reação álcali-agregado no desempenho de estruturas de concreto; Numerical analysis of the effect of influential factors of alkali-aggregate reaction in the performance of concrete structures

Rodrigues, Edmilson Correia
Fonte: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Engenharia Civil; MECÂNICA DAS ESTRUTURAS, ESTRUTURAS DE CONCRETO E ALVENARIA E MATERIAIS E PROCESSOS CONSTRUTIVOS Publicador: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Engenharia Civil; MECÂNICA DAS ESTRUTURAS, ESTRUTURAS DE CONCRETO E ALVENARIA E MATERIAIS E PROCESSOS CONSTRUTIVOS
Tipo: Dissertação Formato: application/pdf
Português
Relevância na Pesquisa
1044.7043%
The aim of this work is the numerical simulation of the mechanical performance of concrete affected by Alkali-Aggregate Reaction or RAA, reported by Stanton in 1940. The RAA has aroused attention in the context of Civil Engineering from the early 80, when they were reported consequences of his swelling effect in concrete structures, including cracking, failure and loss of serviceability. Despite the availability of experimental results the problem formulation still lacks refinement so that your solution remains doubtful. The numerical simulation is important resource for the assessment of damages in structures caused by the reaction, and their recoveries The tasks of support of this work were performed by means of the finite element approach, about orthotropic non-linear formulation, and, thermodynamic model of deformation by RAA. The results obtained revealed that the swelling effect of RAA induced decline of the mechanical performance of concrete by decreasing the margin of safety prior to the material failure. They showed that the temperature influences, exclusively, the kinetics of the reaction, so that the failure was the more precocious the higher the temperature of the solid mass of concrete; O objetivo deste trabalho é a simulação numérica do desempenho Mecânico de membros de concreto afetados pela Reação Álcali-Agregado ou RAA...

Desempenho de argamassas produzidas com agregados reciclados oriundos do resíduo de construção e demolição da Grande Natal-RN; Performance of mortar coating produced with recycled aggregates derived from construction and demolition waste (CDW) produced in the Grande Natal-RN

Araújo, Neuber Nascimento de
Fonte: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Engenharia Civil; MECÂNICA DAS ESTRUTURAS, ESTRUTURAS DE CONCRETO E ALVENARIA E MATERIAIS E PROCESSOS CONSTRUTIVOS Publicador: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Engenharia Civil; MECÂNICA DAS ESTRUTURAS, ESTRUTURAS DE CONCRETO E ALVENARIA E MATERIAIS E PROCESSOS CONSTRUTIVOS
Tipo: Dissertação Formato: application/pdf
Português
Relevância na Pesquisa
940.3954%
The construction industry is responsible for generating a lot of waste because of their activities. Consequently, it is noticeable the occurrence of environmental problems in terms of its disposal in inappropriate places. Faced with this problem, some studies have been conducted with the aim of developing technologies and alternatives for recycling construction and demolition waste (CDW), motivated by the scarcity of natural resources and reduction of environmental problems generated. The research aims to characterize the recycled aggregates derived from construction and demolition waste (CDW) produced in the Greater Natal-RN and analyze the performance of mortar coating produced with recycled aggregates. The study includes the chemical , physical and microstructural characterization of recycled aggregates , as well as conducting microscopic analysis and laboratory tests in the fresh state (consistency index , water retention , bulk density and content of entrained air ) and in the hardened state ( compressive strength , tensile strength in bending , water absorption by immersion and capillary , mass density and void ratio ) for mortars produced from different levels of substitution of aggregates ( 0, 20 %, 40 %, 60 %, 80 % and 100 %). The results were satisfactory...

Desenvolvimento de um equipamento para avaliação do desempenho de geomantas

Bezerra Neto, Carlindo Avelino
Fonte: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Engenharia Civil; MECÂNICA DAS ESTRUTURAS, ESTRUTURAS DE CONCRETO E ALVENARIA E MATERIAIS E PROCESSOS CONSTRUTIVOS Publicador: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Engenharia Civil; MECÂNICA DAS ESTRUTURAS, ESTRUTURAS DE CONCRETO E ALVENARIA E MATERIAIS E PROCESSOS CONSTRUTIVOS
Tipo: Dissertação Formato: application/pdf
Português
Relevância na Pesquisa
940.1652%
O controle sobre os processos erosivos é uma necessidade constatada em vários segmentos da engenharia. A movimentação de terra necessária para a execução de taludes rodoviários, por exemplo, pode resultar em taludes de corte ou aterro vulneráveis à erosão superficial. Dentre as alternativas tecnológicas para controle de erosão a utilização de geossintéticos se apresenta como uma solução potencial. A referida aplicação encontra-se em amplo desenvolvimento em alguns países como, por exemplo, nos EUA. No Brasil, a especificação de geossintéticos para controle de erosão é limitada pela ausência de caracterização desses produtos e de normas nacionais, sendo a única fonte técnica de informação, os catálogos dos fabricantes. Neste contexto, o objetivo deste trabalho é construir um equipamento e desenvolver métodos de ensaio para caracterização e avaliação de geossintéticos utilizados no controle de erosão superficial, com base na ASTM D7101. Além de um simulador de chuvas, o equipamento é composto por uma bancada de testes formada por: rampa de escoamento, mesa de suporte e núcleos de solo. Utilizando a bancada construída, foram realizados ensaios para avaliar o funcionamento do equipamento e o desempenho de uma geomanta na redução da taxa de erosão superficial. Os ensaios foram realizados com intensidades de precipitação de 100 ± 4mm/h e 150 ± 4mm/h...

Análise experimental de vigas constituídas de perfis formados a frio com emendas soldadas submetidas à flexão simples; Experimental analysis of beams made of cold formed steel with welded seams subjected to bending

ALMEIDA, Ariovaldo Fernandes de
Fonte: Universidade Federal de Goiás; BR; UFG; Mestrado em Engenharia Civil; Engenharias Publicador: Universidade Federal de Goiás; BR; UFG; Mestrado em Engenharia Civil; Engenharias
Tipo: Dissertação Formato: application/pdf
Português
Relevância na Pesquisa
942.3247%
The cold-formed steel sheets have been sufficiently used when it is thought of manufacturing a metallic structure with reduced weight. Its use until some time ago in construction was limited to the secondary structures, but, with considerable growth in research involving this type of material together with development of technical standards, made its use a good solution for certain types of light structures. The present work presents considerations on cold-formed steel sheets, the patened steel, processes of welding and the result of experimental tests with beams with composed section of two profiles U constituted with cold-formed steel sheets, manufactured with two types of patened steel produced in Brazil. In some of these beams, welded sections with coated electrode had been used and were made the comparison with the reference beam, where it was possible to study the influence of the process of welding in the ultimate resistance and the ductility of the beam.; Os perfis metálicos formados a frio tem sido bastante usados quando se pensa em fabricar uma estrutura metálica com peso próprio reduzido. O seu uso até a algum tempo atrás na construção civil estava limitado apenas a estruturas secundárias, mas, com o crescimento considerável de pesquisas envolvendo este tipo de material associadas ao desenvolvimento de normas técnicas...

Influência do agregado graúdo reciclado de resíduos da construção predial nas propriedades do concreto fresco e endurecido

NUNES, Wesley Carlos
Fonte: Universidade Federal de Goiás; BR; UFG; Mestrado em Engenharia Civil; Engenharias Publicador: Universidade Federal de Goiás; BR; UFG; Mestrado em Engenharia Civil; Engenharias
Tipo: Dissertação Formato: application/pdf
Português
Relevância na Pesquisa
953.5822%
Recycling waste materials is an efficient way to hinder environmental, social and economic impacts of the civil construction industry. This dissertation aimed at verifying the behavior of different concretes made of coarse recycled aggregate (AGR), mineral fractions collected from the waste (RCD) of a high- rise apartment building (multiple floor building). The RCD has been selectively collected at the building construction site and processed by a jaw crusher. The study focused on the effects of gradual replacements of coarse natural aggregate (AGN) by AGR where the fundamental properties of the fresh and hardened concretes are concerned. The experiment involved the production of three dry aggregate/ceme nt ratios: (3,5 / 1), (5 / 1) and (6,5 / 1) for each concrete family (zero%, 25%, 50%, 75% and 100% replacement contents of AGN by AGR), and thus 15 different concrete mix proportions were manufactured. Workability, entrapped air, and density were the variables analyzed in the fresh concretes. Furthermore, water absorption, density, total pores volume, compressive strength, splitting-tensile strength, and initial-tangent modulus were the properties studied in hardened concretes. The strengths of concretes with AGR contents are lower than those of corresponding reference concretes (zero% of replacement content of AGN by AGR). However...

CONTRIBUIÇÃO AO ESTUDO DAS PROPRIEDADES MECÂNICAS E DA DURABILIDADE DE CONCRETOS COM ESCÓRIA DE ACIARIA ELÉTRICA (EAF) COMO AGREGADO GRAÚDO; CONTRIBUTION TO THE STUDY OF MECHANICAL PROPERTIES AND THE DURABILITY OF CONCRETE WITH SLAG OF Residue (EAF) as aggregate

FARIA, Ricardo Andrade Fernandes
Fonte: Universidade Federal de Goiás; BR; UFG; Mestrado em Engenharia Civil; Engenharias Publicador: Universidade Federal de Goiás; BR; UFG; Mestrado em Engenharia Civil; Engenharias
Tipo: Dissertação Formato: application/pdf
Português
Relevância na Pesquisa
949.373%
The increasing demand for aggregate for uses in engineering stimulated the search for alternative materials. In this way, the civil construction potentially started to be a great consumer of residues from other industries, becoming a great recycle plant. The use of by-product, brings great environmental benefits in relation to the degradation of the environment, as for example, less settlement of residues in earth fill, the reduction of extraction of natural resources, and the exploration of aggregate ores. Steel plants from around the world have a commom problem, that is what to do with all the steel slags generated as a by-product from the steel refining in electric steel plants or oxygen steel plants. There are two points of these process where slags can be generated: the first comes from the electric or oxygen furnace itself (called oxidizing refining) and the second is the laddle metallurgy slag (reduction refining slag), which is the last stage of the steel production. This aims to demonstrate related studies to the use of steel slags (EAF slags) in electric steel plants as coarse aggregate. Expansibility of the steel slag tests had been carried through, compressive strength, tensile strength for diametrical compression, related modulus of deformation and durability tests...

Análise experimental de pilares de concreto armado submetidos à flexo-compressão, reforçados com concreto auto-adensável e conectores; Experimental analysis of reinforced concrete columns under flexural compression, strengthened with self-compacting concrete and connectors

NASCIMENTO, Poliana Paula
Fonte: Universidade Federal de Goiás; BR; UFG; Mestrado em Engenharia Civil; Engenharias Publicador: Universidade Federal de Goiás; BR; UFG; Mestrado em Engenharia Civil; Engenharias
Tipo: Dissertação Formato: application/pdf
Português
Relevância na Pesquisa
1049.373%
Many problems involving cases of ruins of buildings, bridges, etc., specifically ruin of columns, which are among the most important links in the whole structure, due to project flaw, bad execution or even for the evolution and changing habits. Therefore it has been of fundamental importance researches on the experimental behavior of structures. When conducting a strengthening column using dry with increased self-compacting concrete, it has the drawback of a sudden rupture by peeling the reinforcement. For this, there is a need to study the area of adhesion between substrate and to strengthen and create a way of preparation of this interface area so that the column increases may come into ruin in a ductile flexural as well as in a monolithic column. Thus, it s been developed an experimental study in the School of Civil Engineering, Federal University of Goias, based on analysis of the breaking loads, lateral displacements and deformations of the column of materials for different ways of preparing the surface of the column to be strengthened. The experimental phase of this work was based on testing of nine reinforced concrete columns, which are tested under flexural compression, with eccentricity of 60 mm. Two columns were used as reference columns...

Análise da interação solo-estrutura em edifícios sobre estacas; Analysis of soil-structure interaction in buildings on cuttings

ARAÚJO, Adrianne Carvalho de
Fonte: Universidade Federal de Goiás; BR; UFG; Mestrado em Geotecnia e Construção Civil; Engenharias Publicador: Universidade Federal de Goiás; BR; UFG; Mestrado em Geotecnia e Construção Civil; Engenharias
Tipo: Dissertação Formato: application/pdf
Português
Relevância na Pesquisa
949.663%
The joined structure-foundation analysis of buildings is one of the studied themes of Soil- Structure Interaction (SSI). In this research, a numerical tool was developed using the Matlab program to evaluate the soil-structure interaction in buildings, where the problem has been studied in the last years, but has not became a current practice in civil engineering. The developed program, here named as AIEFE, predict the settlement using the Aoki and Lopes (1975) method, using as input data the reaction loads of building columns, calculated in any subroutine of spatial-portico analysis. The commercial program TQS was chosen as this subroutine in the present research. The found foundation settlements were converted in stiffness values and, then, inputted again in the structural analysis, predicting new settlements, but no more considering the foundations as fixed points . The method is iterative, aiming to reach the settlement (or load) convergence. Two examples of buildings supported by piled foundations were analyzed. The first one presented an almost square plant and the other one was typically rectangular. The SSI effects were analyzed in terms of column loads and also stiffness and foundations settlements during the constructive process of the 15-levels studied cases. During the construction of the first building levels...

Levantamento das manifestações patológicas em fundações e estruturas nas edificações, com até dez anos de idade, executadas no estado de Goiás; Survey of pathologies in foundations and structures in buildings with up to ten years old, executed in the state of Goiás

ALVES, Jader Rodrigues
Fonte: Universidade Federal de Goiás; BR; UFG; Mestrado em Engenharia Civil; Engenharias Publicador: Universidade Federal de Goiás; BR; UFG; Mestrado em Engenharia Civil; Engenharias
Tipo: Dissertação Formato: application/pdf
Português
Relevância na Pesquisa
942.1823%
The main objective of this research is to proceed to the rising of the indexes, to identify the pathologies and to characterize the constructions that presented occurrences of pathological manifestations in foundations and structures in the constructions executed in the State of Goiás, with age of up to ten years. The researches was classified as documental, considering that, to make possible the accomplishment of the same, the files of Regional Council of Engineering, Architecture and Agronomy of Goiás were analyzed -Crea/GO, with a total sample of 545 reports. It was observed that most of the processes are concerning the last seven years. This Organ was chosen by the fact that all of the technical documents are elaborated by professionals, and, mainly, for Official Organ to be considered. The Method of the Incidence was adopted as methodology recommended for this study observing that in the reports and decisions, elaborated by Crea-GO doesn't be in the number of occurrences of a same pathology and yes only the incidence of the same. The main conclusions of this research were: the main pathological manifestation was found in the foundations repression with a rate of 37.50% followed by collapse with a rate of 22.50%, both in relation to all the pathologies found in the foundation stage...

Avaliação de concreto com adição de fibras de PET submetido a altas temperaturas; Assessment of concrete made with de PET fiber exposedo to high temperatures

Meneses, Ilzenete Andrade
Fonte: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Engenharia Civil; MECÂNICA DAS ESTRUTURAS, ESTRUTURAS DE CONCRETO E ALVENARIA E MATERIAIS E PROCESSOS CONSTRUTIVOS Publicador: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Engenharia Civil; MECÂNICA DAS ESTRUTURAS, ESTRUTURAS DE CONCRETO E ALVENARIA E MATERIAIS E PROCESSOS CONSTRUTIVOS
Tipo: Dissertação Formato: application/pdf
Português
Relevância na Pesquisa
937.656%
The concrete for centuries constituted an essential structural element in the construction industry due to its relative ease of forming, before the weather durability, low cost, its lower maintenance compared to other materials such as steel. However, when the concrete is exposed to high temperatures tends to lose its mechanical characteristics, and may even result in loss of section, which undermines the stability and mechanical strength of structural elements. The pathologies resulting from exposure to elevated temperatures ranging from cracks, pops up chipping explosives (spalling). Recently, the technology of concrete is closely related to the study of its microstructure. The use of fibers added to concrete has been revealed as a solution to increase the mechanical strength of the concrete, it acts directly on the distribution of efforts to act in the play within the microstructure. In this work we used recycled PET fibers embedded in concrete with 15x2mm fck = 30MPa, water/cement ratio of 0.46, in works made for verification of mechanical strength of this mixture submitted to high temperature. The specimens of concrete with addition of PET fibers were tested after exposure to temperatures: ambient (30ºC), 100°C, 200°C, 300°C...