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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Influência do graute e da taxa de armadura no comportamento da alvenaria de blocos de concreto

Logullo, Bárbara Gonçalves [UNESP] 28 April 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:25:22Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-04-28Bitstream added on 2014-06-13T20:13:42Z : No. of bitstreams: 1 logullo_bg_me_ilha.pdf: 2174691 bytes, checksum: 2bff5d48b8a6abd70b07786d00f61690 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Apresenta-se neste trabalho uma investigação experimental do comportamento da alvenaria estrutural de blocos de concreto, resistência à compressão axial e módulo de elasticidade, em função do emprego de blocos de diferentes resistências, na presença de grautes de resistências variadas e também da existência ou não de armaduras, aplicadas em distintas taxas. Desse modo, são apresentados e comentados os resultados de ensaios de compressão axial em unidades, prismas de três blocos e pequenas paredes, montados com um só tipo de argamassa, mas com blocos de duas resistências distintas, designadas B1 e B2. Os elementos ensaiados são vazios e também preenchidos com grautes de duas resistências, definidas G1 e G2. Além destes, também são ensaiados prismas e paredes armadas, com taxas de armadura ñ 1, ñ 2 e ñ 3. Portanto, são realizados ensaios em prismas e paredes vazias, prismas e paredes grauteadas com as diferentes combinações de classes de bloco e graute e com a combinação de blocos, grautes e taxas de armadura. Com os resultados obtidos foi verificado que o grauteamento praticamente dobrou a resistência do prisma grauteado, e, nas paredes o acréscimo foi médio de 80%, comparado com prisma e parede vazia na área bruta, porém esse aumento não foi proporcional à relação efetiva de áreas. Os prismas grauteados apresentaram diminuição na deformação de ruptura com a utilização de grautes mais rígidos, e, o grauteamento homogeneizou o comportamento de deformabilidade da alvenaria e do bloco que a constitui, no prisma e na parede. Constatou-se, também, que as armaduras não alteraram o comportamento estrutural dos prismas e paredes, nem na sua resistência à compressão axial e nem na sua deformabilidade. / It is presented in this work an experimental investigation of the structural mansory of concrete blocks behavior, resistance to axial compression and elastic modulus, in function of the utilization of blocks of different resistances, with the presence of grout of varying resistances and the existance or not of armour, applied in distinct taxes. By this way, it's shown and commented the trials results of axial compression in units, three-block prisms and small walls, manufactured with just one type of mortar, but with blocks with two distincts resistances, called B1 and B2. The tested elements are empty and filled with grout of two resistances, defined as G1 and G2. Besides them, armoured prism and walls were tested too, with armour taxes called ñ 1, ñ 2 and ñ 3. Hence, the trials are executed in empty prisms and walls, grouted prisms and walls with the different combinations of classes of blocks and grouts and with the combination of blocks, grouts and armour taxes. With the obtained results, it was verified that the grout almost doubled the resistance of the grouted prism and, in walls there was an 80% increase, compared with empty prism and walls in brute area, although this increase was not proportional to the effective relation of areas. The grouted prisms presented a decrease in rupture deformation with the utilization of more rigid grouts, and the grout smoothed the deformability behaviour in mansory and in the block that form it, in prisms and walls. It was noticed too, that the armour do not alter the structure behavior of prisms and walls, not even in theirs resistance to axial compression force, neither to theirs deformability.
12

Influência do graute e da taxa de armadura no comportamento da alvenaria de blocos de concreto /

Logullo, Bárbara Gonçalves. January 2006 (has links)
Orientador: Jefferson Sidney Camacho / Banca: Jorge Luis Akasaki / Banca: João Bento de Hanai / Resumo: Apresenta-se neste trabalho uma investigação experimental do comportamento da alvenaria estrutural de blocos de concreto, resistência à compressão axial e módulo de elasticidade, em função do emprego de blocos de diferentes resistências, na presença de grautes de resistências variadas e também da existência ou não de armaduras, aplicadas em distintas taxas. Desse modo, são apresentados e comentados os resultados de ensaios de compressão axial em unidades, prismas de três blocos e pequenas paredes, montados com um só tipo de argamassa, mas com blocos de duas resistências distintas, designadas B1 e B2. Os elementos ensaiados são vazios e também preenchidos com grautes de duas resistências, definidas G1 e G2. Além destes, também são ensaiados prismas e paredes armadas, com taxas de armadura ñ 1, ñ 2 e ñ 3. Portanto, são realizados ensaios em prismas e paredes vazias, prismas e paredes grauteadas com as diferentes combinações de classes de bloco e graute e com a combinação de blocos, grautes e taxas de armadura. Com os resultados obtidos foi verificado que o grauteamento praticamente dobrou a resistência do prisma grauteado, e, nas paredes o acréscimo foi médio de 80%, comparado com prisma e parede vazia na área bruta, porém esse aumento não foi proporcional à relação efetiva de áreas. Os prismas grauteados apresentaram diminuição na deformação de ruptura com a utilização de grautes mais rígidos, e, o grauteamento homogeneizou o comportamento de deformabilidade da alvenaria e do bloco que a constitui, no prisma e na parede. Constatou-se, também, que as armaduras não alteraram o comportamento estrutural dos prismas e paredes, nem na sua resistência à compressão axial e nem na sua deformabilidade. / Abstract: It is presented in this work an experimental investigation of the structural mansory of concrete blocks behavior, resistance to axial compression and elastic modulus, in function of the utilization of blocks of different resistances, with the presence of grout of varying resistances and the existance or not of armour, applied in distinct taxes. By this way, it's shown and commented the trials results of axial compression in units, three-block prisms and small walls, manufactured with just one type of mortar, but with blocks with two distincts resistances, called B1 and B2. The tested elements are empty and filled with grout of two resistances, defined as G1 and G2. Besides them, armoured prism and walls were tested too, with armour taxes called ñ 1, ñ 2 and ñ 3. Hence, the trials are executed in empty prisms and walls, grouted prisms and walls with the different combinations of classes of blocks and grouts and with the combination of blocks, grouts and armour taxes. With the obtained results, it was verified that the grout almost doubled the resistance of the grouted prism and, in walls there was an 80% increase, compared with empty prism and walls in brute area, although this increase was not proportional to the effective relation of areas. The grouted prisms presented a decrease in rupture deformation with the utilization of more rigid grouts, and the grout smoothed the deformability behaviour in mansory and in the block that form it, in prisms and walls. It was noticed too, that the armour do not alter the structure behavior of prisms and walls, not even in theirs resistance to axial compression force, neither to theirs deformability. / Mestre
13

Propriedades físicas e mecânicas de blocos estruturais produzidos com agregados reciclados de concreto / Physical and mechanical properties of structural blocks produced with recycled aggregates of concrete

Danilo Mascarenhas Prado 15 May 2006 (has links)
Este trabalho estuda a influência da utilização de resíduos de concreto (fração graúda ou miúda) nas características físicas e mecânicas de blocos de concreto estruturais, comparando-as com as características obtidas para blocos produzidos com agregados naturais. Foram utilizados resíduos obtidos de diferentes fontes oriundas de uma indústria de pré-moldados e pesquisados limites para a substituição dos agregados naturais por esses agregados reciclados. Inicialmente, foram realizados ensaios de caracterização dos agregados reciclados de concreto para avaliar o potencial de aplicação de cada um deles. Após serem selecionados os dois agregados mais apropriados para o estudo (resíduos de vigotas e blocos), foram produzidos corpos de prova com três traços em volume 1:20, 1:15 e 1:10, com substituições de 100% e 50% para agregados graúdos e de 33% para agregados miúdos. Quase todos esses traços e substituições foram utilizados para produzir blocos de concreto em uma indústria de pré-moldados, objetivando-se obter resistências à compressão de 4.5, 8.0 e 12.0 MPa. Os resultados obtidos para blocos com agregados reciclados foram então comparados com aqueles obtidos utilizando-se agregados naturais. Observou-se que, apesar de algumas propriedades apresentarem alterações, foram obtidos valores adequados para os parâmetros mais importantes, principalmente quanto à resistência à compressão e à absorção de água. Por fim, foram produzidos e ensaiados prismas com os blocos com agregados reciclados que apresentaram melhor desempenho, sendo avaliados a resistência à compressão e o módulo de deformação. Os resultados mostraram que os valores de eficiência prisma/bloco não foram significativamente alterados e os valores para os módulos de deformação resultaram próximos, tanto para blocos com agregados reciclados quanto para blocos com agregados naturais / This research deals with the influence of the use of recycled concrete aggregate (coarse and fine) for physical and mechanical characteristics of concrete blocks comparing them with those ones obtained from blocks produced with natural aggregates. Residues from different sources of a prefabricated concrete blocks factory were used and limits for substituting natural aggregates for recycled aggregate were tested. First, several characterization tests for different recycled concrete aggregates were carried out in order to evaluate their properties. Two of them were selected and test samples were produced considering three different mix proportions in volume: 1:20, 1:15 and 1:10, with replacements of 100% and 50% of coarse aggregates and 33% of fine aggregates. Almost all of these proportions were used for preparing concrete blocks with three classes of compression strength: 4.5, 8.0 and 12.5 MPa. Then the obtained results were compared with those ones obtained for blocks with natural aggregates. Despite the fact of the properties were not the same, the physical and mechanical characteristics could be considered adequate, mainly regarding compression and water absorption. Finally, some prisms with blocks of recycled aggregate were produced and tested evaluating the results for compression and deformation modulus. One could observe that the strength rate prism/block was not significantly modified and the deformation modulus were similar either considering blocks of recycled aggregate or blocks of natural aggregate
14

Blocos de concreto para alvenaria em construções industrializadas / Concrete blocks for masonry in industrialized construction

José Americo Alves Salvador Filho 26 June 2007 (has links)
A inovação tecnológica na construção civil no Brasil e em outros países ainda é bastante tímida, de modo que o setor é frequentemente apontado como tecnologicamente atrasado. O desenvolvimento insuficiente de novas tecnologias e sua pouca utilização, aliados ao desperdício de materiais, à informalidade e à qualidade de vida dos trabalhadores, tornam o custo da construção excessivamente alto. Apesar de ter havido nos últimos anos uma série de avanços na indústria de blocos de concreto, o que permitiu um grande desenvolvimento na qualidade deste produto, sua utilização ainda está restrita quase que exclusivamente a um procedimento artesanal, cuja qualidade final depende da qualidade da mão-de-obra. Neste contexto, a utilização de materiais de construção que permitam montagens rápidas e com qualidade se tornam necessárias. O presente trabalho apresenta componentes para alvenarias, de alto padrão, desenvolvidos no Laboratório de Materiais Avançados à Base de Cimento da Escola de Engenharia de São Carlos. Estes componentes são encaixáveis, com dimensões padronizadas, que permitem o assentamento sem necessidade de argamassa, facilitando sua utilização na construção. Os blocos possuem aberturas para colocação de armaduras e tubulações de telefonia, hidráulica, elétrica, gás, etc., de forma que possam atender às diversas exigências dos usuários. Para tanto, foi desenvolvido um componente para construção em concreto especial colorido, cuja baixa porosidade e permeabilidade e resistência permitem um perfeito acabamento, dispensando chapiscos, rebocos, emboços e pintura, eliminando assim diversas etapas construtivas. Os resultados alcançados apontam a viabilidade da utilização desse componente estrutural para um tipo diferenciado de construção. / The technological innovation for housing construction in Brazil is still quite tiny, so that, this economic sector is frequently noticed as technologically late. The insufficient development of new technologies and its little employ, allies to the waste of materials, informality and labor quality life, turns construction costs extremely high. Although the progresses in the concrete blocks industry in the last years, what allowed a great development on product quality, its use is still restricted almost exclusively to a craft procedure, which final quality depends on the labor quality. In this perspective, the use of materials that allows fast and quality constructions become necessary. This research presents high end masonry elements developed at the LMABC-SET-EESC-USP. These elements are interlockable, with standardized dimensions, what allows the establishment without mortar bedding, facilitating your use in the auto-construction. The blocks were designed with cores for placement of reinforcements or hydraulics, electric, telecom, gas, and other systems, so that they can assist the users several demands. For it, a special masonry component in colored concrete was developed, whose low porosity, permeability and resistance allows perfect finishes, sparing several constructive stages. The reached results points to the viability of the use as structural component for a distinct kind of construction.
15

Contribuição ao estudo para aplicação do po de serra da madeira em elementos de alvenaria de concreto não estrutural

Dantas Filho, Flavio Pedrosa 26 November 2004 (has links)
Orientador: Vitor Antonio Ducatti / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-04T08:19:10Z (GMT). No. of bitstreams: 1 DantasFilho_FlavioPedrosa_M.pdf: 1664624 bytes, checksum: 3cacc7f6d0b7f9d6f41a2cf089712398 (MD5) Previous issue date: 2004 / Resumo: A preocupação com o grave problema da geração de resíduos na construção civil e na indústria vem, cada vez mais, despertando a conscientização da necessidade de realização de estudos com vistas a melhorar o ciclo de produção e adequar a destinação dos resíduos gerados. Neste sentido, a reciclagem se apresenta como uma grande alternativa. Este trabalho visa a reciclagem do pó de serra da indústria madeireira que é um resíduo indesejável, tendo atualmente como única opção de uso, sua queima ou descarte final. A reciclagem deste material, vem contribuir para a formação de uma nova matéria-prima, possibilitando sua utilização como material de construção civil. É estudada a influência de diferentes teores da adição do pó de serra tratado em substituição parcial ao agregado miúdo mineral na fabricação de blocos de concreto para alvenaria de vedação e como elementos de enchimento para pré-lajes. Determinou-se a resistência à compressão, teor de umidade, absorção de água, área líquida e condutividade térmica para vários teores de pó de serra em substituição parcial e total ao agregado miúdo mineral. A análise dos resultados permite concluir que a utilização do pó de serra como agregado miúdo na confecção dos blocos de concreto até 50% em volume aumentou a resistência térmica com redução de peso, atendendo as prescrições da norma para alvenaria de vedação. Também, observa-se uma diminuição da resistência à compressão em relação ao bloco de concreto de referência. A utilização da argamassa de cimento e pó de serra como elementos de enchimento para pré-lajes, atendeu às normas brasileiras. É possível concluir, ainda, que a utilização do pó de serra em substituição parcial ou total ao agregado miúdo mineral, contribui para um programa de reciclagem, diminuindo a demanda do agregado miúdo para a confecção dos blocos de concreto e elementos de enchimento das pré-lajes / Abstract: Concern with residue from the construction industry calls upon the need for studies aiming to optimize production cycle as well as to better dispose of such residues. Evidently, recycling is certainly an excellent option. The work herein described concerns recycling of sawdust, a very undesirable residue generated by wood industries, which nowadays can only be disposed of by burning or dumping. Recycling such material engenders a new product to be used in building construction. It is studied the influence of different quantities of sawdust, partially substituting fine aggregate mineral, used to produce hollow concrete masonry blocks and elements for precast plank. Their compression load capacity, humidity, water absorption factor, net area and thermal conductivity were determined. Final results analysis leads to the conclusion that employing sawdust, up to 50% in volume, to produce concrete blocks increases their thermal isolation capacity besides reducing their total weight. However, a reduction on their compression loads capability was observed, as compared to the reference concrete blocks. Utilization of mortar of cements and sawdust as filling elements for precast plank, satisfies the brasilian norms. Thus, it is possible to conclude that the use of sawdust in partial or total substitution of the fine aggregate, contributes towards a recycling program, reducing the need for fine aggregate to produce concrete blocks and filling elements for precast plank / Mestrado / Edificações / Mestre em Engenharia Civil
16

Polyfunkční dům v Bratislavě v části Podunajské Biskupice / Multifunctional house in Bratislava district Podunajské Biskupice

Puschenreiterová, Kristína January 2015 (has links)
Master thesis contains project documentation of low-energy multifunctional house with a full basement, three floors and finished with a flat roof. It is a detached house situated in a residential building area in capital city of Slovakia - Bratislava, district Podunajské Biskupice. The basement walls and columns are made of reinforced concrete. The basement is used as a garage with twenty-two parking spaces for flats owners and there is also placed a workshop room. Above-ground floors are designed as a reinforced concrete frame filled circumferentially with light-weight concrete blocks. Exterior cladding is covered by heat insulation. The interior vertical, non-load-bearing walls are made of plasterboard. On the ground floor are two shops and a restaurant with a terrace. There are eleven flats on the other two floors. On the second floor are seven double-bedroom flats with an open plan kitchen lounge area, four of them have a balcony. On the third floor are four flats with a terrace, three of them are two double bedroom flats with an open plan kitchen lounge area, and the fourth one is a one double bedroom flat with open plan kitchen lounge area. The entrance for shops and main entrance for flats are on the north-west side. The entrance for the restaurant is on the north-east side.
17

Seismic Performance Assessment of Ductile Reinforced Concrete Block Structural Walls

Siyam, Mustafa 06 1900 (has links)
This dissertation is relevant to structural engineers focusing on seismic design of structures using reinforced masonry. Specifically the thesis focuses on the seismic performance of reinforced masonry shear walls as seismic force resisting systems. / Reinforced masonry (RM) has been gaining a wide acceptance in the low- and mid-rise construction market as an economic and durable structural system. However, challenges still exist in the area of seismic design because of the poor performance of unreinforced masonry during recent earthquake events in Iran 2003, Haiti 2010, Japan 2011, New Zealand 2011 and Nepal 2015. The dissertation investigated the seismic performance of six concrete block structural walls in an effort to evaluate their force-, displacement- and performance- based seismic design parameters. The walls fall under the ductile shear wall/special reinforced wall seismic force resisting system (SFRS) classification according to the current North American masonry design standards. More specifically, the dissertation is focused on evaluating if such walls, designed under the same prescriptive design provisions, having different cross-section configurations would possess similar seismic performance parameters. This was established through an experimental and analytical program by subjecting the walls to a displacement controlled quasi-static cyclic analysis. Different wall configurations were tested including, rectangular, flanged and slab-coupled walls. Test results confirmed that walls designed under the same SFRS classification, but with different configurations, have different seismic performance parameters that included ductility capacity; yield and post yield displacement; stiffness degradation; period elongation and equivalent viscous damping. The current North American masonry design provisions do not account for such difference in the ductility capacities between the walls. The thesis analyses were concluded by quantifying the seismic vulnerability of a RM SFRS comprised of shear walls similar to those tested, through the development of collapse fragility curves and the assignment of an adjusted collapse margin ratio, ACMR following the FEMA P-58 and P-695 guidelines. The system were deemed acceptable since the ACMR was greater than ACMR10% (2.35 > 2.31). Therefore, the selected RM SFRS which was designed to meet the prescriptive requirements of the ductile masonry walls classification of the CSA S304 (CSA 2014), shows potential capacity against collapse under high intensity earthquakes in one of the highest seismic zones in western Canada and it should be considered as a viable SFRS to be used in seismic design. The procedure described in the chapter can be adopted to investigate the collapse fragility of other SFRS in different seismic regions through careful selection and scaling of the ground motion records associated with such region's seismicity. / Dissertation / Doctor of Philosophy (PhD)
18

Pros and Cons of Using Large Concrete Blocks in an Office Building Structure : Comfort, Stability, Sustainability

Baban, Shwan, Abolfazl, Asliyalfani January 2023 (has links)
In 2019, the cement industry used 280 million tons of oil equivalent, contributing to 7% of totalindustrial energy consumption. This resulted in 2.4 billion tons of CO2 emissions, constituting26% of the industrial sector’s CO2 output and 7% of global energy-related emissions. On theother hand, It is affordable, safe, and readily available, thanks to its construction error resistance. C3C is a company that takes advantage of waste concrete that has been produced and useit to mold concrete blocks that has different functions. This is a big environmental benefit. Themain function of these blocks has been to function as temporary or permanent partitions walls orsafety walls for accidental loads. The aim of this study is to investigate the feasibility and performance of a temporary office structure that is built majorly out of these C3C lego blocks froma comfort, stability and sustainability point of view. This data aids construction professionalsseeking cost-effective alternatives to traditional methods. Retrofitting and cascading offer economic and environmental benefits. Our goal is to discover innovative, sustainable constructionapproaches for future generations. The results show the importance of insulation positioning forthe comfort point of view. To ensure stability and analyse if the separation of the blocks occur,four RFEM models are made with focus on the tensile stresses and uplifting deflection of thewalls. In conclusion, this study provides ideas on how to design a temporary structure usingC3C lego blocks.Keywords: Concrete blocks, C3C blocks, FE models, life cycle analysis, mechanical connections, CO2 emissions.
19

The beginning

Garstang, Stephen R. January 1989 (has links)
On the most simple level the projects presented here are intended to fulfill the requirements of a kindergarten. At the next level they represent an investigation into the roles of order in design. In these projects I have chosen to deal with four orders inherent to architecture. The most basic is the order of material, fundamental and inescapable. Linked to this is the order of geometry, which must be sympathetic to the order of material, but goes further in establishing an overall pattern. Giving additional meaning to the overall pattern is the hierarchical order of the spaces. Finally, the social order animates the hierarchy with the abstract notions of the individual and collective. The core of this thesis lies in the integration of these orders into a coherent system, a deep structure adaptable to a variety of conditions. This deep structure gathers the orders, allowing for the necessary freedom while giving the equally indispensable restraint. The system provides a vehicle, an operational method from which one may approach each new circumstance. The following pages present the physical manifestations of this deep structure at several scales. From the realm of the site to the geometry of small objects the single overriding structure gives order, bringing together disparate elements into comprehensible wholes, intensifying the experience and ultimately infusing the whole with a spirit, architecture. / Master of Architecture
20

The early developmental history of concrete block in America

Hall, James P. January 2009 (has links)
This thesis outlines the early developmental history of concrete block in America with special attention being placed on the years leading up to the St. Louis Louisiana Purchase Exposition of 1904. In general, the history of concrete block in contemporary building material histories begins with the innovations in block machinery that took place at the turn of the 20th century. However, the history of concrete block begins much earlier than these innovations. Harmon S. Palmer invented the first commercially successful concrete block machine in 1900, but there were many reasons why concrete block became widely used during the first half of the 20th century. The establishments of a domestic Portland cement industry, the innovations in concrete block machinery, and the marketing and promotion of concrete and concrete block at the 1904 St. Louis Louisiana Purchase Exposition, are all major reasons why concrete block began to be widely used in America. / Concrete : primer -- Concrete : a brief history -- Concrete block : an early history -- Portland cement -- The commercialization of concrete block -- Concrete block on the world stage : the 1904 Louisiana Purchase Exposition. / Department of Architecture

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