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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.
41

The effect of different Ordinary Portland cement binders, partially replaced by fly ash and slag, on the properties of self-compacting concrete

Almuwbber, Omar Mohamed January 2015 (has links)
Thesis submitted in fulfilment of the requirements for the degree Master of Technology: Civil Engineering in the Faculty of Engineering at the Cape Peninsula University of Technology / Self-compacting concrete (SCC) is a flowable self-consolidating concrete which can fill formwork without any external vibration. A self-compacting concrete mix requires the addition of superplasticiser (SP), which allows it to become more workable without the addition of excessive water to the mixture. The effect of different CEM I 52.5N cements produced by one company at different factories on self-compacting concrete was investigated. The properties of SCC are highly sensitive to changes in material properties, water content and addition of admixtures. For self-compacting concrete to be more accepted in South Africa, the effect that locally sourced materials have on SCC, partially replaced with extenders, needs to be investigated. The European guidelines for SCC (2005) determined the standard, through an extensive study, for the design and testing of self-compacting concrete. Using these guidelines, the properties of self-compacting concrete with the usage of local materials were investigated. The effect on SCC mixes was studied by using four cements; two types of SPs – partially replaced with two types of fly ash; and one type of slag. Mix design and tests were done according to the European Specification and Guidelines for Self-Compacting Concrete (2005). Using locally sourced materials (different cements, sand, coarse aggregate, fly ashes and slag), mixes were optimised with different SPs. Optimisation was achieved when self-compacting criteria, as found in the European guidelines, were adhered to, and the binders in these required mixes were then partially replaced with fly ash and slag at different concentrations. Tests done were the slump flow, V-funnel, L-box, sieve segregation resistance as well as the compressive strength tests. The results obtained were then compared with the properties prescribed by the European guidelines. The cements reacted differently when adding the SPs, and partially replacing fly ash and slag. According to the tests, replacing cement with extenders – in order to get a sufficient SCC – seemed to depend on the chemical and physical properties of each cement type, including the soluble alkali in the mixture, C3A, C3S and the surface area. The range, in which the concentration of these chemical and physical cement compounds should vary – in order to produce an acceptable SCC partially replaced by extenders – was determined and suggested to the cement producer. The main conclusion of this project is that cement properties vary sufficiently from factory to factory so as to influence the performance of an SCC mix. The problem becomes even bigger when such cements are extended with fly ash or slag, and when different SPs are used. When designing a stable SCC mix, these factors should be taken into account.
42

Compactacao isostatica a quente do po de aco rapido AISI M2

LIBERATI, JOAO F. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:45:27Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:59:17Z (GMT). No. of bitstreams: 1 07155.pdf: 5285109 bytes, checksum: f414fcad3e4bf9dd06580fa7fa97ce54 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
43

Factors influencing laboratory vibratory compaction

Troost, Jan J January 1987 (has links)
Includes bibliography. / The thesis consists of a literature review and a limited experimental investigation in a soils laboratory. The objective of the literature review is to determine what standard laboratory test methods based on vibration exist for the control of compaction, to what soil types these tests are applicable and what the factors are which affect laboratory vibratory compaction. The study revealed that extensive research has been carried out in the USA and Europe, where standard laboratory compaction tests exist for the determination of the maximum dry density of cohesionless, free-draining soil. The US methods are based on the use of a vibratory table, while the European practice is based on the use of a vibratory tamper. No standard tests appear to exist for soil exhibiting cohesion, though limited research has been carried out in the USA into the behaviour of such soils under laboratory vibratory compaction. The factors; frequency, amplitude, mould size and shape surcharge intensity and manner of application, soil type, time of vibration, number of layers and moisture content are all reported to have an effect on the maximum dry density achievable. It has been recognised that significant interaction occurs between the factors affecting vibratory compaction, but the extent of the interaction appears to be only partly understood. The objective of the limited experimental program was to determine whether a specific graded crushed stone could be compacted to Modified AASHTO maximum dry density with a laboratory vibratory compaction technique using a vibratory table, and how this could best be achieved. The effects on dry density of changing the frequency, the time of vibration, mould size, surcharge pressure, grading and moisture content were investigated. It is concluded that the graded crushed stone in question can be compacted to Mod. AASHTO maximum dry density but that before reliable reproducible results can be achieved with this type of test further work is necessary. Such research should be aimed at investigating the interaction effect between the amplitude of vibration, the soil type and the type and intensity of the applied surcharge pressure.
44

Estudo das propriedades no estado fresco e endurecido do concreto leve autoadensável / Study of the properties in fresh and hardened state of the lightweight self-compacting concrete

Verzegnassi, Emerson, 1968- 28 August 2018 (has links)
Orientadores: Rosa Cristina Cecche Lintz, Luísa Andréia Gachet Barbosa / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Tecnologia / Made available in DSpace on 2018-08-28T13:32:52Z (GMT). No. of bitstreams: 1 Verzegnassi_Emerson_M.pdf: 3873734 bytes, checksum: 73682762affd1136f183e9120a07a536 (MD5) Previous issue date: 2015 / Resumo: Com a descoberta de aditivos químicos e adições minerais muitos tipos diferentes de concreto surgiram ao longo das últimas décadas. Porém o peso próprio do concreto convencional é considerado a sua maior desvantagem. Com isso abre-se campo para um material que apesar de ser conhecido pelos romanos, era pouco utilizado, o concreto com agregados leves. Muitas pesquisas surgem e em aproximadamente duas décadas aparece o concreto autoadensável e mais recentemente o concreto leve autoadensável. Este trabalho propõe o estudo deste material ainda pouco explorado o concreto leve autoadensável. Para isso são produzidos concretos com argila expandida em duas granulometrias diferentes: uma graúda em substituição total ao agregado graúdo de massa normal e uma miúda em substituição parcial ao agregado miúdo. São elaboradas três famílias de traços de concreto com consumos diferentes de cimento, 320, 360 e 440 kg/m³ de concreto, e realizados ensaios no estado fresco (anel J, funil V e caixa L) e endurecido (resistências à compressão e à tração, determinação do módulo de elasticidade, absorção e densidade). Os concretos leves foram classificados como auto adensáveis e apresentaram bons resultados quanto ao fator de eficiência e resistência sendo possível estabelecer equações de correlação para seu módulo de elasticidade. Para os ensaios de densidade observaram-se concretos leves com massas mínimas de até 1550 kg/m³ e resistências à compressão superiores aos valores estipulados pela norma NBR NM 35 para as densidades apresentadas em todas as misturas / Abstract: With the discovery of admixtures and mineral additions many different types of concrete emerged over the last decades. But the own weight of conventional concrete is considered their biggest disadvantage. With this opens up the field for a material that despite being known to the Romans, it was little used, the concrete with lightweight aggregates. Much research and come in about two decades appears the self compacting concrete and more recently the lightweight concrete self compacting. This work proposes the study of this material still little explored concrete lightweight self compacting. For this are produced concrete with expanded clay in two different particle sizes: one coarse in total replacement of coarse aggregate of normal mass and a fine partially substituting fine aggregate. Are designed three families of concrete mixtures with different cement consumption, 320, 360 and 440 kg / m³ of concrete, and the tests carried out in the fresh state (ring J, V funnel and L box) and hardened (resistance to compression and traction , determining the modulus of elasticity, absorption, and density). The concretes were classified as self compacting and showed good results as to efficiency and resistance factor being possible to establish a correlation equations for its modulus of elasticity. For the density tests were observed concretes with minimum masses of up to 1550 kg / m³ and compressive strengths greater than those stipulated by NBR NM 35 standard for the densities presented in all mixtures / Mestrado / Tecnologia e Inovação / Mestre em Tecnologia
45

Effect Of Chemical And Mineral Admixtures On The Fresh Properties Of Self Compacting Mortars

Christianto, Heru Ari 01 August 2004 (has links) (PDF)
Fresh properties of mortars are important factors in altering the performance of self compacting concrete (SCC). Measurement of the rheological properties of the fine mortar part of concrete is generally used in the mix design of SCC. It can be stated that SCC rheology can be optimized if the fine mortar part of concrete is designed properly. However, measurement of the rheological properties is often impractical due to the need for complex equipment. Therefore, more practical methods of assessing mortar workability are often preferred. In this study, four mineral admixtures, three superplasticizers (SP) and two viscosity modifying admixtures (VMA) were used to prepare self compacting mortar (SCM). The mineral admixtures included fly-ash, brick powder, limestone powder, and kaolinite. Two of the SPs were polycarboxylate based and another one was melamine formaldehyde based. One of the viscosity modifying admixtures was based on an aqueous dispersion of microscopic silica and the other one was based on high molecular weight hydroxylated polymer. Within the scope of the experimental program, 43 mixes of SCM were prepared from different materials with keeping the amount of mixing water constant. Workability of the fresh mortar were determined using V - funnel and slump flow tests. The setting time of the mortars, were also determined. The hardened properties that were determined included the ultrasonic pulse velocity (UPV) and the strength which was determined at 7, 28, and 56 days. It was concluded that among the mineral admixtures used, only fly-ash and limestone powder increased the workability of the mixes. The two polycarboxylate based SPs yield approximately the same workability and the melamine formaldehyde based SP was not as effective as the other two.
46

Vibratory hammer compaction of bitumin stabilized materials

Kelfkens, Rex Willem Constantyn 12 1900 (has links)
Thesis (MScEng (Civil Engineering))--Stellenbosch University, 2008. / There are currently well established compaction methods being used in laboratories globally to prepare specimens for material testing. None of these methods provides the repeatability and reproducibility, ease of execution or simulation and correlation to field compaction desired by engineers. The research presented in this report was aimed at the development of a new or adapted compaction method for bituminous stabilized materials (BSM) that would address the aforementioned factors, by making use of a vibratory hammer. Along with this, a new protocol was to be established. The initial vibratory hammer that was tested was the Kango 637®. This specific vibratory hammer suffered irreparable damage to the gearbox during the research. A replacement Kango hammer could not be purchased, therefore a substitute hammer was purchased i.e. a Bosch GSH 11E®, for which back-up service and replacement parts are readily available throughout South Africa. Significant progress had been made with the development of a laboratory compaction protocol for BSM using the Kango Hammer. The specifications of the Bosch® hammer showed it was superior in terms of power, weight and other technical features. Comparative testing was therefore carried out. This allowed for the adaptation of the results achieved to that point. Extensive experimentation was then carried out using two types of BSM i.e. foamed bitumen (80/100 bitumen) and bitumen emulsion (60/40 Anionic Stable Grade) stabilized material. The initial material used for the experimentation was a G2 quality graded crushed stone. Additional material was also obtained from a recycling project taking place along the N7 near Cape Town. The N7 material was used to perform correlation experiments so as to determine how representative the laboratory compacted specimens were to field compacted material. Results showed that the vibratory hammer is capable of producing specimens for testing in the laboratory as well as providing a possible benchmark method for accurately controlling the quality of work on site i.e. field density control. This was done by identifying the time to and level of refusal density compaction. The level of refusal density compaction was expressed as a percentage of Mod AASHTO compaction and using current specifications, a potentially new site compaction level specification was determined. In order to asses the material applicability of the vibratory hammer compaction method, tests regarding moisture sensitivity analysis were carried out on a G5 material. The vibratory compaction protocol includes a specification for the type of hammer, guide-frame, surcharge weight, compaction moisture and number of layers. Vibratory compaction can be used to prepare two types of specimens: • Specimens for triaxial testing with a diameter of 150mm and a height of 300mm • Specimens for laboratory testing with a diameter of 150mm and a height of 125mm. Tests showed that the material properties prove to have an influence on the compactability of the material. Material from the N7 recycling project had been milled out thus altering the grading and including some RAP. This in turn influenced compaction. The vibratory hammer moisture curve was found to shift slightly to the left when compared to the Mod AASHTO moisture curve. The variability of the vibratory hammer was found to be well below the specified variability of 15%. Repeatability experiments on G5 material indicate that vibratory hammer compaction may be used on lesser quality granular materials. A recommended procedure for the compaction of BSM was developed following the experimentation results.
47

Formulation des différents bétons (BAP, BHP et BFUP) à haute teneur en additions minérales : optimisation pour améliorer le coulage, la résistance au jeune âge et la durabilité des bétons / Formulation of different concretes (SCC, HPC and UHPFRC) with high content mineral additions : optimization to improve casting, early-age strength and durability of concrete

Benaicha, Mouhcine 25 November 2013 (has links)
L'industrie du béton est une source importante d'émissions de gaz CO2 lors de la production de ciment. Une des solutions proposées à l'industrie de la construction est de remplacer le ciment par des matières premières secondaires moins polluantes (ex : filler calcaire, fumée de silice), qui peuvent également améliorer les caractéristiques rhéologiques du liant et accroître la durabilité du béton.Le but principal de cette thèse est donc de : (1) standardiser la formulation de béton issue des différents travaux de recherche publiés tout en assurant une bonne compréhension de ses propriétés rhéologiques; (2) adapter ces principes aux conditions de réalisation (prise en compte des caractéristiques des matériaux locaux utilisés); et (3) vérifier dans le laboratoire ou sur le terrain la viscosité plastique et le seuil d’écoulement des bétons.Outre les moyens expérimentaux classiques nous avons utilisé, dans notre étude, un autre moyen de caractérisation rhéologique : c’est l’écoulement de béton dans un V-Funnel couplé à un canal horizontal en plexiglas. Dans un premier temps nous cherchons à comprendre la corrélation entre la viscosité et les paramètres rhéologiques de béton en se basant sur des modèles proposés dans la littérature. À partir de là, nous cherchons à présenter le modèle qui décrit le comportement de béton. Pour ce faire, nous proposons une corrélation théorique entre la viscosité plastique du béton frais et le temps d’écoulement dans le V-Funnel, puis nous comparons cette solution théorique avec des mesures expérimentales rapportées dans la littérature. / The concrete industry is an important source of carbon dioxide gas emissions during cement production. One of the proposed solutions to the construction industry is to replace the cement by less polluting secondary raw materials (e.g. limestone filler, silica fume), which can also improve the rheological properties of binder and increase the concrete durability.Thus, the development of self-compacting concrete can be seen as an attempt to reduce the environmental impact of the construction. Similarly, the structure optimization also aims at reducing the quantity (in volume) of concrete and is reflected in the use of high performance concrete and ultra performance fiber-reinforced concrete (HPC and UPFRC).The most widely adopted approach to quantify these rheological properties is to experimentally measured the shear stress versus strain rate using a concrete rheometer.In addition to traditional experimental tests such as the V-funnel, spread, sieve stability and L box, in our study we used another test of rheological characterization: it is the flow of concrete in a V-Funnel and then in a horizontal channel Plexiglas.The main purpose of this thesis is to: (1) standardize the concrete formulation outcome of various research works published while ensuring a good understanding of its rheological properties, (2) adapt these principles to the realization conditions (taking into account characteristics of local materials used), and (3) check, in the laboratory or in the field, the plastic viscosity and the flow threshold of concrete.
48

Uso de finos de resíduos de construção e demolição em concreto autoadensável

Santos, Iago Lopes dos January 2018 (has links)
O concreto autoadensável (CAA) é um concreto especial com a capacidade de fluir e preencher completamente todos os espaços das fôrmas pela ação de seu peso próprio, sem que haja ocorrência de bloqueio e segregação da mistura. Contudo, para alcançar essas características, normalmente esse concreto é dosado com um maior teor de materiais finos e/ou com aditivo modificador de viscosidade. Os agregados provenientes de Resíduos de Construção e Demolição (RCD) já estão sendo utilizados na produção de concretos, porém o uso dos materiais finos de agregados reciclados não é recomendado para a produção de concretos convencionais. Entretanto, acredita-se que em CAA esses materiais finos podem ser uma oportunidade interessante, tanto para a questão da reutilização desses resíduos, conseguindo uma destinação nobre para esses materiais com baixa demanda no mercado, como na manutenção das propriedades deste concreto, sendo os principais agentes do controle de segregação. Desta forma, o presente trabalho consistiu em estudar a influência da utilização de finos de RCD (concretos, argamassas e tijolos cerâmicos), separadamente, em substituição parcial ao agregado miúdo natural, nas principais propriedades do concreto autoadensável no estado fresco (fluidez, habilidade passante e resistência à segregação) e no estado endurecido (resistência à compressão e módulo de elasticidade), bem como avaliar seu desempenho quanto à durabilidade (absorção de água e penetração de íons cloretos). Os resultados demostraram perda de fluidez e boa coesão nos concretos autoadensáveis que empregaram agregados reciclados. No entanto, ainda conferem boas características de autoadensabilidade, atendendo as condições normativas para uso em estruturas correntes de engenharia. No que tange às propriedades mecânicas, foi observado aumento de resistência à compressão e decréscimo do módulo de resistência para concretos com finos de RCD. No quesito de durabilidade, os concretos com agregados reciclados apresentaram valores mais elevados para absorção de água por capilaridade e penetração de íons cloretos em comparação aos concretos de referência. / Self-compacting concrete (SCC) is a special concrete with the ability to flow into and completely fill all spaces within the formworks only by the action of their own weight, without blocking and segregation of the mixture. However, to achieve these characteristics, normally this concrete needs to be mixed with more content of fine materials and/or viscosity modifiers additives. The aggregates from Construction and Demolition Wastes (CDW) are used for concrete production, but the use of fine recycled aggregate is not recommended for the production of conventional concrete. Although, it is believed that in SCC these fine aggregates can be an interesting opportunity for the reuse of these wastes, achieving a noble destination for these materials with low demand in the market, as for the maintenance of the properties of this concrete, being the main agents of segregation control. So, the present research consisted in studying the influence of the use of CDW fines aggregates (concretes, mortars and ceramic bricks, separately) to replace the natural sand in the main properties of the self-compacting concrete in the fresh state (flowability, passing ability and segregation resistance) and in the hardened state (compressive strength and modulus of elasticity), as well as to evaluate its performance in terms of durability (water absorption and chloride penetration). The study results showed loss of flowability and increased cohesion in the self-compacting concretes that used recycled aggregates. However, they still confer good characteristics for self-compacting concrete, taking into account the normative conditions for using current engineering structures. With respect to the mechanical properties, it was observed an increase of compressive strength and decrease of the modulus of elasticity for concrete with CDW fines aggregates. In terms of durability, concretes with recycled aggregates presented higher values for capillarity water absorption and penetration of chloride ions compared to the references concretes.
49

Avaliação do potencial do uso da sílica de casca de arroz obtida através da queima controlada como substituição parcial ao cimento Portland na produção de concretos autoadensáveis

Dalcin, Jarbas Bressa 01 September 2016 (has links)
Submitted by Cátia Araújo (catia.araujo@unipampa.edu.br) on 2017-01-26T11:47:11Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Avaliação do potencial do uso da sílica de casca de arroz obtida através da queima controlada como substituição parcial ao cimento Portland na produção de concretos au.pdf: 5610666 bytes, checksum: 59bf1f9b8c485e95150b2a114381adde (MD5) / Approved for entry into archive by Cátia Araújo (catia.araujo@unipampa.edu.br) on 2017-01-26T11:47:27Z (GMT) No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Avaliação do potencial do uso da sílica de casca de arroz obtida através da queima controlada como substituição parcial ao cimento Portland na produção de concretos au.pdf: 5610666 bytes, checksum: 59bf1f9b8c485e95150b2a114381adde (MD5) / Made available in DSpace on 2017-01-26T11:47:27Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Avaliação do potencial do uso da sílica de casca de arroz obtida através da queima controlada como substituição parcial ao cimento Portland na produção de concretos au.pdf: 5610666 bytes, checksum: 59bf1f9b8c485e95150b2a114381adde (MD5) Previous issue date: 2016-09-01 / O presente estudo tem como objetivo avaliar o potencial uso da Sílica de Casca de Arroz (SCA), obtida de queima controlada, como material de substituição parcial em massa ao Cimento Portland (CP) na produção de concretos autoadensáveis (CAA). A SCA empregada neste trabalho foi produzida em condições controladas em um sistema de combustão com leito fluidizado, tendo como resultado uma sílica altamente amorfa e de boa qualidade. Foram avaliados os resultados do comportamento reológico do CAA no estado fresco e a resistência mecânica no estado endurecido de um concreto de referência, sem o uso de SCA, e de cinco concretos produzidos a partir de substituições parciais de 5%, 10%, 15%, 20% e 25% de SCA em relação à quantidade de massa do cimento. Em todos os traços foram utilizado 15% de cinza volante (CV) adicionada à massa do material aglomerante, a fim de auxiliar na diminuição do atrito entre as partículas dos agregados com o cimento. O traço do concreto de referência foi obtido utilizando o procedimento de caráter experimental proposto pelo Método de Gomes. Este traço foi analisado também pelo Método do Empacotamento Compressível, sendo assim, definidos os outros traços com substituições. As amostras foram caracterizadas no estado fresco de acordo com a norma brasileira ABNT NBR 15823/2010, através de: ensaios de espalhamento no cone de Abrans e Anel “J”, de fluidez no funil “V” e habilidade passante na caixa “L” e caixa “U”. Os resultados mostram que os concretos produzidos com SCA possuem boa capacidade de fluidez. No estado endurecido foram verificadas as resistências mecânicas de compressão axial e tração por compressão diametral dos CAAs nas idades de 7, 28, 56 e 91 dias. Os resultados dos ensaios indicam que é possível substituir CP por SCA sem que haja prejuízo às características mecânicas dos CAAs e ainda obter ganhos técnicos e econômicos. O melhor concreto, levando em conta todos os aspectos estudados, foi com 15% de substituição de CP por SCA. / This study aims to evaluate the potential use of rice husk silica (RHS), obtained under controlled burning conditions, such as partial replacement material to the Portland Cement (PC) in the production of self-compacting concrete (SCC). The RHS employed in this study was produced under controlled conditions in a fluidized bed combustion system, resulting in highly amorphous silica and of good quality. We evaluated the results of the rheological behavior of SCC in the fresh state and strength in the hardened state of a reference concrete without the use of RHS and five concrete made from partial substitution 5%, 10%, 15%, 20% and 25% in RHS relative to the amount of concrete mass. In all traces were used 15% of Fly Ash (FA) is added to the mass of the binder material to assist in reducing friction between particles of the aggregates with cement. The trace of the reference concrete was obtained using the experimental procedure proposed by Gomes method. This trait was also analyzed by the method of packaging compressible and based on this method are defined partial strokes with other PC for RHS substitutions. After obtaining the characteristics of the materials and dosages of SCCs, these were featured in the fresh according to the Brazilian standard NBR 15823/2010, as follows: Spreading tests on cone Abrans and "J-ring", pour in "V-Funnel" and passing ability in the "L-box" and "U-box". The results shows that concrete made with RHS have good flow capacity. In the hardened state the mechanical resistances were checked axial compression and tension by diametrical compression of SCCs at the ages of 7, 28, 56 and 91 days. The test results indicate that it is possible to replace PC with RHS without prejudice to the characteristics of SCCs and still get technical and economic gains. The best concrete, taking into account all the points studied, was the one with replacement of 15% of PC for RHS.
50

Concreto auto-adensável: caracterização da evolução das propriedades mecânicas e estudo da sua deformabilidade por solicitação mecânica, retração e fluência. / Self-compacting concrete: characterization of the evolution of mechanical properties and study of its deformability under mechanical load, shrinkage and creep.

Marques, Ana Carolina 29 April 2011 (has links)
O concreto auto adensável (CAA) é um material novo cujas propriedades mecânicas precisam ser estudadas. Ele apresenta em sua composição maior quantidade de argamassa e agregados graúdos de menores dimensões, que podem torná-lo mais deformável que o concreto convencional. Em contrapartida, o melhor empacotamento das partículas no estado fresco do CAA e a sua maior resistência (para uma mesma relação a/c) pode atuar no sentido oposto. Além disso, os modelos de previsão disponíveis na norma brasileira não levam em consideração os concretos especiais. O objetivo deste trabalho é verificar se modelos de previsão disponíveis na literatura são adequados para prever a fluência e a retração do CAA. Este estudo envolve aspectos de sua caracterização por meio de ensaios em laboratório, de retração, de fluência e de outras propriedades mecânicas como resistência à compressão, resistência á tração e módulo de elasticidade. Para o ensaio de fluência foram avaliadas as influências das condições ambientais (através de corpos de prova mantidos em ambiente controlado e sem controle de umidade e temperatura) e idade de carregamento. A partir dos resultados obtidos experimentalmente, foi feita a sua comparação com os modelos de previsão do ACI, EC2, NBR, B3 e GL. O estudo da deformação do CAA também foi feito por meio da monitoração de uma viga protótipo protendida, seguida da comparação das deformações medidas com as obtidas por um programa de elementos finitos. A partir dos resultados experimentais, observa-se que dentre os modelos de previsão de fluência e retração estudados, o que mais se adéqua aos resultados obtidos experimentalmente, é o fornecido pelo ACI e GL. A utilização do modelo de previsão do ACI pelo programa de elementos finitos gerou bons resultados de previsão de deformações quando comparados com os resultados medidos. Em relação à função de fluência, nota-se que a norma brasileira é adequada para o concreto estudado. / Self-compacting concrete (SCC) is a new material and its mechanical properties have yet to be studied. It has a higher amount of mortar and smaller coarse aggregates which make it more deformable. On the other hand, the packing of the particles in fresh SCC and its larger strength (at a constant water/cement ratio) may act in the opposite way. Besides, the prediction models provided by the Brazilian Code do not take special concretes into account. The main objective of this work is to verify if the creep and shrinkage prediction models available in the literature can predict those properties of a SCC. This study involves aspects of its characterization by tests in laboratory of creep, shrinkage and other mechanical properties, such as compressive strength, splitting tensile strength and modulus of elasticity. For the creep test, the influence of environmental conditions (for specimens kept in an environment with and without temperature and humidity controlled) and age at loading were evaluated. From the obtained experimental results, a comparison was made to the values obtained from the ACI, EC2, NBR, B3 and GL prediction models. The deformability of SCC was analyzed by monitoring a post-tensioned beam prototype followed by the comparison of the measured deflection and strain long the time to those obtained from a finite element model. From the obtained experimental results of creep and shrinkage, the most adequate prediction models are the ACI and GL models. The use of the ACI model with the finite element method produced good results when compared to the experimental measurements of deflection and strain of the prototype beam. With respect to the compliance creep function, it can be noticed that the model provided by the Brazilian Code is adequate to the studied SCC.

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