Submitted by Irene Nascimento (irene.kessia@ufpe.br) on 2016-06-27T17:24:22Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação_Maria Victória Leal de Almeida Nacimento (2016).pdf: 1980230 bytes, checksum: eef736353b0156d4355d07d1b2ad6f70 (MD5) / Made available in DSpace on 2016-06-27T17:24:22Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação_Maria Victória Leal de Almeida Nacimento (2016).pdf: 1980230 bytes, checksum: eef736353b0156d4355d07d1b2ad6f70 (MD5) Previous issue date: 2016-02-16 / A utilização de resíduos em materiais cimentícios, tem sido desenvolvida para melhorar a qualidade ambiental, diminuindo os resíduos gerados. O RPP é um resíduo industrial produzido em grande escala pela indústria cerâmica, ele foi utilizado nesse trabalho sendo incorporado em blocos intertravados de concreto. Os blocos intertravados de concreto foram escolhidos dentre os materiais cimentícios, por não ter sua trabalhabilidade comprometida, quando se trata de adicionar um material pulverulento, pois é produzido por vibro-compressão. Foi realizada a otimização do empacotamento dos agregados, para a produção dos blocos intertravados de concreto, através de método matemático. Também foi otimizada, através de método experimental a relação água/cimento. O traço de referência, encontrado após as otimizações, foi 1: 2,68: 2,32 (cimento: areia: pedrisco), com relação água/cimento de 0,45, atendeu as especificações da NBR 9781 (ABNT, 2013), com relação a resistência à compressão. A partir do traço de referência foi realizado o empacotamento matemático para a incorporação do RPP. O resíduo foi considerado como agregado no empacotamento, ele foi incorporado nas seguintes porcentagens: 3% de RPP, 6% de RPP, 9% de RPP, e 12% de RPP, afim de avaliar a influência do resíduo nos blocos intertravados de concreto, nas propriedades do estado endurecido. A presença do RPP, reduziu a absorção de água tendendo a trazer para o admitido pela NBR 9781 (ABNT, 2013), manteve a resistência a abrasão de acordo com as especificações da NBR 9781 (ABNT, 2013), embora tenha prejudicado a resistência a compressão, sendo promissor a sua utilização, em blocos intertravados de concreto, em situações onde não há tráfego de veículos, como em: passeios públicos, praças, parques infantis, áreas que necessitem de drenagem. O traço com a incorporação do resíduo, que de uma forma geral obteve os resultados mais satisfatórios foi o traço 2 (3% RPP), que apesar da resistência à compressão média ter sido de 14,26 MPa menor que o especificado pela norma, apresentou uma taxa de absorção média de 6,60%, e em relação a resistência à abrasão apresentou uma cavidade média de 17,50 mm. / To incorporate residues in cimentitious materials has been developed to improve the environmental quality, reducing the amount of disposed residues. The ceramic porcelain industry generates a large amount of porcelain tile polishing residue. This work proposes to incorporate this tile polishing residue in concrete interlocking blocks. The concrete interlocking blocks were chosen due to the addition of a powder material not prejudice their workability, once they are molded by vibrocompression. It was determined the best packaging by a mathematical method. The water-cement ratio was also optimized by the experimental method. The achieved reference mix proportion after all optimizations was 1:2.68:2.32 (cement: sand: gravel) with ratio water-cement ratio 0.45. The compressive strength of the reference mix proportion is according to the NBR 9781 (ABNT, 2013). In the sequence, based on this reference mix, the incorporation of the residue was also mathematically optimized. The residue was considered as an aggregate on the packaging method. The residue was incorporated at the following percentages: 3%, 6%, 9% and 12% in order to evaluate its influence on the hardened state properties of the concrete interlocking blocks. The presence of the tile polishing residue reduces the water absorption, tending to bring the values to the admitted one by the NBR 9781. The abrasion resistance was in agreement with the NBR 9781 (ABNT, 2013). However, the compressive resistance was reduced, limiting the applications of the concrete interlocking blocks with the addition of tile polishing residue where there is no vehicle traffic, as in public footpaths, parks, playgrounds or areas requiring drainage. In a general way, the most satisfactory result among the evaluated mixes incorporating tile polishing residue was to the mix 2 (3% of residue). Despite the average compressive strength was 14.26 MPa lower than the specified by the standard, this mix presented the average absorption of 6.60% and 17.50 mm as a medium cavity liner in the abrasion resistance test.

Resumo: Diante do grande crescimento da alvenaria estrutural no país, muitas fábricas de blocos de concreto vieram por necessidade, buscar por otimizações do seu processo produtivo, visto que, projetos mais arrojados, acabam exigindo maiores controles de qualidade. A proposta deste estudo é melhorar a produção destes artefatos de concreto por meio de otimizações simples que reduzem o custo e garantem uma produção eficiente na fábrica. Estudar a fundo os vários parâmetros de formação de um traço de concreto seco, tais como coesão, textura, energias de adensamento e resistência à compressão axial, todos os fenômenos dependentes entre si, torna-se muito complexo se avaliado em um único trabalho. No entanto, propor um estudo que colete informações apresentadas por vários autores, facilita na otimização e criação de uma pesquisa que possa contribuir na dosagem para concretos secos, em especial, na fabricação de blocos estruturais. Neste estudo, adaptaram-se para laboratório alguns equipamentos de uso comum para confecção destes artefatos de concreto, possibilitando a correlação direta de corpos de prova cilíndricos com os blocos. Uma das adaptações é o estudo baseado na padronização da energia de compactação, proporcionada pelo equipamento para ensaios de mini-proctor, simulando assim, a máquina vibro-prensa. Outras correlações como coesão e resistência à compressão, também foram possíveis de obter no laboratório, reduzindo então, as interferências constantes no processo produtivo da fábrica, ocasião verificada em vários outros estudos. Diante do exposto, foi possível avaliar com boa segurança os resultados. O estudo foi desenvolvido em três etapas, sempre buscando a maior massa específica seca compactada da mistura de agregados, inicialmente na primeira etapa, foi utilizado somente dois agregados (areia fina e pedrisco), conforme... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Given the substantial growth of structural masonry in Brazil, many concrete block companies have seen the need to optimize their production process, since more challenging projects require greater quality control. This study proposes to improve the production of concrete artifacts by means of simple optimizations that reduce costs and ensure the company's efficient production. Studying in depth the various parameters of the formation of dry concrete trace, such as cohesion, texture, density energy and axial compressive strength, all the particularities interdependent on one another become very complex when assessed in a single study. However, proposing a study that collects the information submitted by various authors, expedites optimizing and creating a research study which may assist in improving the dosage for dried concrete, particularly in the manufacture of structural blocks. In this study, some commonly used manufacturing equipment, such as concrete artifacts, were laboratory-adapted, enabling a direct correlation of the cylindrical specimens with the blocks. One of the adjustments is the study based on the standardization of compaction energy, provided by the mini-proctor testing equipment, thus simulating the vibro press machine. Other correlations such as cohesion and compressive strength were also obtained in the laboratory, therefore reducing the constant interferences in the plant's production process, observed in many other studies. In this manner, it was possible to reliably assess the results. The study was conducted in three stages, always seeking the highest compressed dry specific mass of the mixture of aggregates. In the first stage, only two aggregates were used (fine sand and pebbles), commonly used at the plant. The second stage included adding the coarse sand and stone powder to correct the lack of resistance promoted by the high amount of fine sand from... (Complete abstract click electronic access below) / Orientador: Jefferson Sidney Camacho / Coorientador: Maria da Consolação F. de Albuquerque / Banca: Jorge Luís Akasaki / Banca: Paulo César Primo Agostinho / Mestre

Stress-strain relations for unconfined and confined concrete are proposed to overcome some shortcomings of existing commonly used models. Specifically, existing models are neither easy to invert nor integrate to obtain equivalent rectangular stress-block parameters for hand analysis and design purposes. The stress?strain relations proposed are validated for a whole range of concrete strengths and confining stresses. Then, closed form expressions are derived for the equivalent rectangular stress-block parameters. The efficacy of the results is demonstrated for hand analysis applied for deriving the moment-curvature performance of a confined concrete column. Results are compared with those obtained from a computational fiber-element using the proposed stress-strain model and another widely used model; good agreement between the two is observed. The model is then utilized in the development of a new structural system that utilizes the positive attributes of timber and concrete to form a parallel. Timber has the advantage of being a light weight construction material, easy to handle, is environmentally friendly. However, large creep deflections and significant issues with sound transmission (the footfall problem) generally limit timber use to small spans and low rise buildings. Concrete topping on timber sub-floors mitigate some of these issues, but even with well engineered wood systems, the spans are relatively short. In this study, a new structural system called structural boxed-concrete, which utilizes the positive attributes of both timber and reinforced concrete to form a parallel system (different from timber-concrete composite system) is explored. A stress-block approach is developed to calculate strength and deformation. An analytical stress-block based moment-curvature analysis is performed on the timber-boxed concrete structural elements. Results show that the structural timber-boxed concrete members may have better strength and ductility capacities when compared to an equivalent ordinary reinforced concrete member.

Stress-strain relations for unconfined and confined concrete are proposed to overcome some shortcomings of existing commonly used models. Specifically, existing models are neither easy to invert nor integrate to obtain equivalent rectangular stress-block parameters for hand analysis and design purposes. The stress?strain relations proposed are validated for a whole range of concrete strengths and confining stresses. Then, closed form expressions are derived for the equivalent rectangular stress-block parameters. The efficacy of the results is demonstrated for hand analysis applied for deriving the moment-curvature performance of a confined concrete column. Results are compared with those obtained from a computational fiber-element using the proposed stress-strain model and another widely used model; good agreement between the two is observed. The model is then utilized in the development of a new structural system that utilizes the positive attributes of timber and concrete to form a parallel. Timber has the advantage of being a light weight construction material, easy to handle, is environmentally friendly. However, large creep deflections and significant issues with sound transmission (the footfall problem) generally limit timber use to small spans and low rise buildings. Concrete topping on timber sub-floors mitigate some of these issues, but even with well engineered wood systems, the spans are relatively short. In this study, a new structural system called structural boxed-concrete, which utilizes the positive attributes of both timber and reinforced concrete to form a parallel system (different from timber-concrete composite system) is explored. A stress-block approach is developed to calculate strength and deformation. An analytical stress-block based moment-curvature analysis is performed on the timber-boxed concrete structural elements. Results show that the structural timber-boxed concrete members may have better strength and ductility capacities when compared to an equivalent ordinary reinforced concrete member.

Made available in DSpace on 2014-06-11T19:25:21Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-02-01Bitstream added on 2014-06-13T20:53:08Z : No. of bitstreams: 1 felipe_as_me_ilha.pdf: 2392820 bytes, checksum: 9c6e04fef232018e3760dee715984441 (MD5) / Universidade Estadual Paulista (UNESP) / Diante do grande crescimento da alvenaria estrutural no país, muitas fábricas de blocos de concreto vieram por necessidade, buscar por otimizações do seu processo produtivo, visto que, projetos mais arrojados, acabam exigindo maiores controles de qualidade. A proposta deste estudo é melhorar a produção destes artefatos de concreto por meio de otimizações simples que reduzem o custo e garantem uma produção eficiente na fábrica. Estudar a fundo os vários parâmetros de formação de um traço de concreto seco, tais como coesão, textura, energias de adensamento e resistência à compressão axial, todos os fenômenos dependentes entre si, torna-se muito complexo se avaliado em um único trabalho. No entanto, propor um estudo que colete informações apresentadas por vários autores, facilita na otimização e criação de uma pesquisa que possa contribuir na dosagem para concretos secos, em especial, na fabricação de blocos estruturais. Neste estudo, adaptaram-se para laboratório alguns equipamentos de uso comum para confecção destes artefatos de concreto, possibilitando a correlação direta de corpos de prova cilíndricos com os blocos. Uma das adaptações é o estudo baseado na padronização da energia de compactação, proporcionada pelo equipamento para ensaios de mini-proctor, simulando assim, a máquina vibro-prensa. Outras correlações como coesão e resistência à compressão, também foram possíveis de obter no laboratório, reduzindo então, as interferências constantes no processo produtivo da fábrica, ocasião verificada em vários outros estudos. Diante do exposto, foi possível avaliar com boa segurança os resultados. O estudo foi desenvolvido em três etapas, sempre buscando a maior massa específica seca compactada da mistura de agregados, inicialmente na primeira etapa, foi utilizado somente dois agregados (areia fina e pedrisco), conforme... / Given the substantial growth of structural masonry in Brazil, many concrete block companies have seen the need to optimize their production process, since more challenging projects require greater quality control. This study proposes to improve the production of concrete artifacts by means of simple optimizations that reduce costs and ensure the company’s efficient production. Studying in depth the various parameters of the formation of dry concrete trace, such as cohesion, texture, density energy and axial compressive strength, all the particularities interdependent on one another become very complex when assessed in a single study. However, proposing a study that collects the information submitted by various authors, expedites optimizing and creating a research study which may assist in improving the dosage for dried concrete, particularly in the manufacture of structural blocks. In this study, some commonly used manufacturing equipment, such as concrete artifacts, were laboratory-adapted, enabling a direct correlation of the cylindrical specimens with the blocks. One of the adjustments is the study based on the standardization of compaction energy, provided by the mini-proctor testing equipment, thus simulating the vibro press machine. Other correlations such as cohesion and compressive strength were also obtained in the laboratory, therefore reducing the constant interferences in the plant’s production process, observed in many other studies. In this manner, it was possible to reliably assess the results. The study was conducted in three stages, always seeking the highest compressed dry specific mass of the mixture of aggregates. In the first stage, only two aggregates were used (fine sand and pebbles), commonly used at the plant. The second stage included adding the coarse sand and stone powder to correct the lack of resistance promoted by the high amount of fine sand from... (Complete abstract click electronic access below)

This thesis is focused on designing a new multipurpose building with parts used for apartments, administration offices and a bar. The land, which the building is situated on, is located in the city of Olomouc. The structure consist of five above-ground floors and one underground floor, where a garage is designed. The vertical supporting construction are made of reinforced cast-in-place concrete columns, the horizontal of reinforced concrete cast-in-place boards, other vertical walls are made of sand-lime and aerated concrete blocks. The roof is warm flat.