Dissertations / Theses on the topic 'Aggregates (Building materials)'
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Palmquist, Shane M. "Compressive behavior of concrete with recycled aggregates /." Thesis, Connect to Dissertations & Theses @ Tufts University, 2003.
Find full textAdviser: Daniel C. Jansen. Submitted to the Dept. of Civil Engineering. Includes bibliographical references (leaves 146-152). Access restricted to members of the Tufts University community. Also available via the World Wide Web;
Trimble, Nicholas Robert. "Experimental assessment of aggregates." Thesis, Montana State University, 2007. http://etd.lib.montana.edu/etd/2007/trimble/TrimbleN0807.pdf.
Full textCheng, Ken. "Optical gradation for crushed limestone aggregates." Morgantown, W. Va. : [West Virginia University Libraries], 2000. http://etd.wvu.edu/templates/showETD.cfm?recnum=1753.
Full textTitle from document title page. Document formatted into pages; contains x, 179 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references (p. 149-153).
Khachatryan, Hayk. "Spatial investigation of mineral transportation characteristics in the state of Washington." Online access for everyone, 2007. http://www.dissertations.wsu.edu/Thesis/Spring2007/H_Khachatryan_122806.pdf.
Full textFRANCESCONI, LORENA. "New building materials in structural engineering: “Structural concretes made with Coarse and Fine recycled aggregates”." Doctoral thesis, Università degli Studi di Cagliari, 2012. http://hdl.handle.net/11584/266080.
Full textZheng, Jianjun. "Mesostructure of concrete stereological analysis and some mechanical implications /." Delft : Delft University Press, 2000. http://books.google.com/books?id=N81RAAAAMAAJ.
Full textVera, Marco A. "A touch of froth : how bubble-particle aggregates take the strain; an investigation into aspects of froth zone recovery in mineral flotation /." St. Lucia, Qld, 2002. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe16112.pdf.
Full textFung, Wing-kun. "The use of recycled concrete in construction." Click to view the E-thesis via HKUTO, 2005. http://sunzi.lib.hku.hk/hkuto/record/B30517643.
Full textMarsh, Peter School of Chemical Engineering & Industrial Chemistry UNSW. "Effect of shear-induced breakup and restructuring on the size and structure of aggregates." Awarded by:University of New South Wales. School of Chemical Engineering and Industrial Chemistry, 2005. http://handle.unsw.edu.au/1959.4/20643.
Full textSwift, Gregory Allen. "Characterization of coarse aggregate angularity using digital image processing." Diss., Rolla, Mo. : University of Missouri-Rolla, 2007. http://scholarsmine.mst.edu/thesis/pdf/Swift_09007dcc8042a3c4.pdf.
Full textVita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed February 4, 2008) Includes bibliographical references (p. 65-69).
Ahn, Nam-shik. "An experimental study on the guidelines for using higher contents of aggregate micro fines in Portland cement concrete." Digital version:, 2000. http://wwwlib.umi.com/cr/utexas/fullcit?p9992742.
Full textMora, Carlos F. "Particle size and shape analysis of coarse aggregate using digital image processing." Thesis, Hong Kong : University of Hong Kong, 2000. http://sunzi.lib.hku.hk/hkuto/record.jsp?B22030153.
Full textKrezel, Zbigniew Adam, and n/a. "Recycled aggregate concrete acoustic barrier." Swinburne University of Technology, 2006. http://adt.lib.swin.edu.au./public/adt-VSWT20060821.154340.
Full textKrezel, Zbigniew Adam. "Recycled aggregate concrete acoustic barrier." Australasian Digital Theses Program, 2006. http://adt.lib.swin.edu.au/public/adt-VSWT20060821.154340.
Full textSubmitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Civil Engineering, Swinburne University of Technology - 2006. Typescript. Includes bibliographical references.
Sengupta, Anandraj. "Effect of specimen geometry on ultrasound diffusion in cement-based aggregates." Thesis, Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/22578.
Full textRoper, Matthew Brent. "Evaluation of laboratory durability tests for stabilized aggregate base materials /." Diss., CLICK HERE for online access, 2007. http://contentdm.lib.byu.edu/ETD/image/etd1846.pdf.
Full textRhee, Hakjun. "Inferring traffic induced sediment production processes from forest road particle size distributions /." Thesis, Connect to this title online; UW restricted, 2006. http://hdl.handle.net/1773/5459.
Full textReyes, Jaime. "Quantifying the role of coarse aggregate strength on resistance to load in HMA." To access this resource online via ProQuest Dissertations and Theses @ UTEP, 2007. http://0-proquest.umi.com.lib.utep.edu/login?COPT=REJTPTU0YmImSU5UPTAmVkVSPTI=&clientId=2515.
Full textZhu, Jianhua. "Characterization of cement-kiln-dust stabilized base/subbase aggregate /." Full-text version available from OU Domain via ProQuest Digital Dissertations, 1998.
Find full textCastro-Fernandez, Pedro Luis. "Optimization of laboratory performance of hot mixed asphalt concrete with Costa Rican raw materials." abstract and full text PDF (free order & download UNR users only), 2006. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3209957.
Full textEdwards, Derek Oswald. "An investigation into possible means of increasing the strength of lightweight high strength concrete." Thesis, [Hong Kong] : University of Hong Kong, 1993. http://sunzi.lib.hku.hk/hkuto/record.jsp?B1331161X.
Full textMason, Craig. "An evaluation of the Bailey method to predict voids in the mineral aggregate." Morgantown, W. Va. : [West Virginia University Libraries], 2006. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=4899.
Full textTitle from document title page. Document formatted into pages; contains viii, 75 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 61-62).
Edwards, Jonathan Paul. "Laboratory characterisation of pavement foundation materials." Thesis, Loughborough University, 2007. https://dspace.lboro.ac.uk/2134/3067.
Full textFung, Wing-kun, and 馮永根. "The use of recycled concrete in construction." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2005. http://hub.hku.hk/bib/B30517643.
Full textLim, Chen Leong. "Effects of maximum size coarse aggregate and superplasticizer on concrete strength." Thesis, Virginia Polytechnic Institute and State University, 1985. http://hdl.handle.net/10919/50049.
Full textMaster of Science
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Babendreier, Justin Eric. "Near aggregation: a time and frequency domain analysis using state trajectories and transfer function residues." Thesis, Virginia Polytechnic Institute and State University, 1987. http://hdl.handle.net/10919/91080.
Full textM.S.
Campos, Marco Antonio. "Estudo do reaproveitamento de isoladores eletricos de porcelana como agregados em argamassas e concretos." [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/257861.
Full textDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo
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Resumo: Todo material de construção após certo tempo de uso apresenta um desgaste que compromete a sua eficiência, fazendo com que a substituição e o descarte sejam imprescindíveis. Os isoladores elétricos de porcelana, após um dado período de uso, perdem suas funções isoladoras, tendo necessidade de serem substituídos, e o seu descarte mensal pelas concessionárias do setor elétrico brasileiro atinge dezenas de toneladas. Em muitos casos o depósito destes isoladores é executado de forma desordenada havendo o comprometimento das áreas de preservação ambientais e de mananciais. Durante o processo de fabricação desses isoladores elétricos também são gerados resíduos, chegando até a 10% do total produzido, cujo descarte é feito no lixo pelas indústrias cerâmicas. Estes dois tipos de rejeitos causam na natureza um passivo de material que leva muitos anos para sua decomposição. Assim, a caracterização deste material cerâmico e o desenvolvimento de um estudo que viabilize seu emprego em substituição aos agregados comumente usados em argamassas e concretos, é uma alternativa para a racionalização do descarte desse material e preservação da natureza. Para o uso de resíduos dos isoladores de porcelana na construção civil é necessário sua moagem em granulometrias similares aos agregados graúdos e miúdos comuns. Este trabalho estudou dosagens de concreto e argamassa com substituições paulatinas de isoladores moídos, comparando algumas de suas propriedades com traços de referência feitos com agregados comuns. Para cada traço foram estudadas as propriedades mecânicas, a trabalhabilidade, a cura e a durabilidade. Pelo fato dos isoladores de porcelana terem características similares aos agregados comuns após a moagem, sua utilização em argamassas e concretos, para os traços moldados e tipos de cura realizados, substituindo parcialmente o agregado, foi bastante satisfatória, principalmente quando o agregado substituído foi o agregado miúdo
Abstract: Every construction material after sometime of using presents wastages which compromises its efficiency and turns indispensable its substitution or disposal. Porcelain electrical insulators, after a certain time of use, lose their insulator functions and are needed to be substituted and its monthly disposal in the brazilian electric sector comes to more than ten tons. In many cases the deposit of these insulators is done in a messy way compromising the environment and springs. During the manufacturing process of these electric insulators, wastes are generated coming up to 10% of the total production and the disposal is done by the pottery industries in the garbage. These two types of rejection cause in nature a passive material which takes many years for its decomposition. Therefore the characterization of this pottery material and the development of a study substituting the aggregate materials used in mortars and concretes, is an alternative of the rationalization of the discard of this material and preservation of the environment. For the use of waste of the porcelain insulators in the civil construction, it is needed to grind them in grinders, similar to great and tiny common aggregates. This work studied concrete and mortar portions with gradual substitutions of ground insulators, comparing some of its properties with reference features done with common aggregates. For each feature were studied the mechanical properties, the working, the cure and the durability. Because of the porcelain insulators have similar characteristics to the common aggregates after the grind, their use in mortar and concretes for the feature patterns and types of cure performed, substituting partially the aggregates, it was quite satisfactory mainly when the substituted aggregate was the small aggregate
Mestrado
Arquitetura e Construção
Mestre em Engenharia Civil
Pelissari, Viviane. "Propriedades de concretos produzidos através da utilização de agregados reciclados de concreto." Universidade Tecnológica Federal do Paraná, 2016. http://repositorio.utfpr.edu.br/jspui/handle/1/1869.
Full textThe recycling of waste is an option to minimize the environmental impact of the significant amount of waste generated by production activities in the construction segment. Thus, the aim of this study is to evaluate the use of recycled coarse aggregate concrete (ARC) to replace the natural coarse aggregate (AGN) for the production of concrete with compressive strength of 30 MPa. The experimental program began with physical and particle size characterization of the recycled coarse aggregate concrete (ARC), and for comparison with the properties of natural coarse aggregate (AGN). Based on the knowledge of these properties, the next step was the production of concrete. Different procedures to reduce the effect of absorption of water by recycled concrete aggregate at the fresh state were studied. Also it was evaluated the effect of using different amounts (0, 10%, 20%, 50% and 100%) replacement of the natural coarse aggregate for concrete recycled coarse aggregate in to the properties of concrete at the fresh state and at the hardened state. Although it has been verified a decrease in the compressive strength values in relation to the reference concrete (without the presence of ARC), for all AGN replacement percentages by ARC was reached the value specified compressive strength (30 MPa). With regard to the modulus of elasticity and splitting tensile strength, it was found that the reduction in results intensifies with increasing percentage of ARC incorporated into the mixture. The values recorded for water absorption, in turn, gradually increased in proportion to the amount of the ARC.
Smith, Benjamin Joshua. "Use of asphalt pavement analyzer to study in-service hot mix asphalt performance." Master's thesis, Mississippi State : Mississippi State University, 2004. http://library.msstate.edu/etd/show.asp?etd=etd-07132004-151942.
Full textRêgo, Wellington Amorim. "Caracterização física dos saibros da região metropolitana do Recife utilizados em argamassa." Universidade Católica de Pernambuco, 2008. http://www.unicap.br/tede//tde_busca/arquivo.php?codArquivo=208.
Full textIt was accomplished in the Metropolitan Area of Recife in the municipal districts of Abreu e Lima, Araçoiaba, Cabo de Santo Agostinho, Camaragibe, Igarassu, Ipojuca, Itamaracá, Itapissuma, Moreno, Olinda, Recife, Jaboatão dos Guararapes and São Lourenço da Mata the collection of materials that they serve as Clay-Shale, in lied explored already commercially, with the objective of evaluating the best characteristic of that Clay-Shale and the application in mortars in the building site, as well as his/her way use no more empiric. For that it was made right the rehearsals of physical characterization through the analysis granulométrica with sedimentation in agreement with ABNT-NBR 7181/1984, the consistence (liquidity limit according to ABNT-NBR 6459/1984 and plasticity limit according to ABNT-NBR 7180/1984). The determination of the specific mass of the grains of the soil in agreement with ABNT-NBR 6508/1984, contraction limit in agreement with ABNT-NBR 7183/1982. The obtained results indicate that significant influence exists in the amount of clay and in the contraction degree.
Campos, Marco Antonio. "Análise microestrutural e das propriedades mecânicas e de durabilidade de argamassas e concretos com isoladores elétricos de porcelana." [s.n.], 2011. http://repositorio.unicamp.br/jspui/handle/REPOSIP/258505.
Full textTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo
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Resumo: Pesquisas para utilização de materiais reciclados e/ou inservíveis da construção civil em seus insumos, concretos e argamassas, é prática recorrente há seis décadas no mundo. No Brasil este uso vem ganhando destaque a cerca de vinte anos principalmente com os entulhos de construção e da cerâmica vermelha. Há uma lacuna a ser preenchida pela cerâmica branca, em especial pelos isoladores elétricos de porcelana, pois seu passivo nacional anual é de 25.000 toneladas proveniente sobretudo da substituição de peças obsoletas. O objetivo deste trabalho foi comprovar a utilização desta porcelana em concretos e argamassas através de sua incorporação com diferentes graus de moagem, variando de granulometria similar ao cimento até aos agregados, miúdo e graúdo, além do estudo referente a influência da camada de esmalte externa aos isoladores através de ensaios mecânicos, de durabilidade e de imagens por MEV e EDS. Para a adição da cerâmica ao cimento nos teores em massa de 5%, 10%, 25%, 50% e 70%, nas argamassas a melhora nos resultados dos ensaios realizados comprovam sua atividade pozolânica e sua potencialidade de uso. Nos ensaios dos concretos com isoladores de porcelana substituindo o agregado miúdo comum ou ambos os agregados, nos teores de 25%, 50%, 75% e 100%, os aumentos de resistências à compressão simples e à tração por compressão diametral obtidos foram superiores a 50% quando comparados aos valores do concreto de referência. A influência da camada de esmalte superficial dos isoladores não foi constada nos ensaios realizados, sendo este mais um fator pró-utilização desta porcelana. As melhoras conferidas às argamassas e aos concretos, quando moldados com agregados ou aglomerantes cerâmicos em suas propriedades mecânicas e de durabilidade acompanhadas dos ensaios de imagens comprovam a utilização dos isoladores elétricos de porcelana nos insumos da construção civil oferecendo com isso às indústrias cerâmicas uma alternativa de uso a esta porcelana e diminuindo a produção de cimento e a extração dos agregados
Abstract: Researches for using recycled materials and/or useless for civil building in input, concretes and mortars, is a practice used for six decades in the world. In Brazil this use is standing out for about20 years mainly with the construction waste and the red ceramic. There is a gap to be fulfilled by the white ceramic especially by the porcelain electric insulators, because of its national passive which is of 25,000 tons proceeded from the substitution of obsolete parts. The purpose of this work is to confirm the utility of this porcelain in concretes and mortars through its incorporation with different degrees of grinding, varying its grinding similar to cement till the aggregates, tiny and great, besides the study referring to the external enamel surface influence to isolators through mechanical test, durability and by SEM and EDS images. Increasing the ceramic to cement in the mass theors of 5%, 10%, 25%, 50% and 70% in the mortar, the improvement in the test results performed, confirm its pozzolanic activity and its potential use. In the concrete test with porcelain insulator substituting the tiny common aggregate or both the aggregates, in theors of 25%, 50%,75% and 100%, the increase in resistance to compressive strength and traction by diametral compression obtained were superior to 50% when compared to the value of the referenced concrete. The influence of the superficial enamel of the insulator was not noticed in the performed tests, therefore being this one more factor for the use of this porcelain. The improvements noticed to the mortars and the concretes, when molded with aggregates or ceramic waste in their mechanical properties and durability followed by image test, confirm the utility of porcelain electric insulator in the input of civil construction offering with this to the ceramic industries an alternative of use to this porcelain and decreasing the cement production and the extraction of aggregates
Doutorado
Recursos Hidricos, Energeticos e Ambientais
Doutor em Engenharia Civil
Nascimento, Maria da Conceição Aguiar do. "Utilização da cinza do bagaço de cana-de-açúcar (CBC) em substituição parcial ao agregado miúdo em concreto não estrutural." Universidade Católica de Pernambuco, 2016. http://tede2.unicap.br:8080/handle/tede/954.
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Brazil is the world's largest non-sugar-alcohol complex that has been expanding in recent times, driven by the advent of bioenergy, exerting a leadership in all segments. The residue generated at the end of the sugarcane bagasse milling process is used for the generation of energy by burning in boilers. At the end of the burning as residual ash are released into the environment inadequately, and may cause environmental problems due to the generation of waste as a sugarcane bagasse ash. The interest of the research is to justify the demand through a job offer from the sugarcane bagasse ash (CBC) in concrete structures, due to the large volume of generation and the concern with the environment. The objective of this research is to evaluate the performance of the conventional contract made of sugar cane residues proved from mills. The results were reported with a 0%, 20% and 40% substitution of natural sand by BCC, where this mixture may contribute to a compound more difficult than conventional concrete. It is also concluded that although the use of CBC has not significantly reduced the final value of m³ of concrete, the gain in relation to the mechanical performance was higher. It can be concluded that the specimens produced have obtained sufficient mechanical strength to be dismantled, transported and conditioned prior to use, in the same way as the referents.
O Brasil é o maior produtor mundial no complexo sucroalcooleiro que vem se expandindo nos últimos tempos, impulsionado pelo advento da bioenergia, exercendo a liderança em todos os segmentos. O resíduo gerado ao final do processo de moagem do bagaço da cana-de-açúcar é utilizado para a geração de energia por meio da queima em caldeiras. Ao final da queima as cinzas residuais são lançadas no meio ambiente de forma inadequada, podendo causar problemas ambientais em decorrência da geração de resíduos como a cinza do bagaço de cana-de-açúcar. O interesse desta pesquisa justifica-se pela necessidade de se avaliar a possibilidade do emprego da cinza do bagaço da cana-de-açúcar (CBC) em estruturas de concreto, devido ao grande volume de geração e a preocupação com o meio ambiente. O objetivo desta pesquisa é avaliar o desempenho do concreto convencional confeccionado de resíduos de cana-de-açúcar proveniente de usinas. Os resultados foram apresentados com a substituição de 0%, 20% e 40% da areia natural por CBC, onde essa mistura pode contribuir para um composto mais durável que o concreto convencional. Conclui-se, também, que apesar do uso da CBC não ter diminuído significativamente o valor final do m3 do concreto, o ganho em relação ao desempenho mecânico foi maior. Pode-se concluir que os corpos-de-prova produzidos obtiveram resistência mecânica suficiente para serem desmoldados, transportados e acondicionados antes do uso, da mesma forma que os de referência.
Soto, Nicolle Talyta Arriagada. "Avaliação do uso de agregado de resíduo de construção civil nas propriedades do concreto no slump para fabricação de artefatos de concreto." Universidade Tecnológica Federal do Paraná, 2017. http://repositorio.utfpr.edu.br/jspui/handle/1/2569.
Full textOne of the applications of aggregates from the recycling of civil construction waste (CCW) is in no slump concrete manufacturing. This type of concrete is used in the manufacture of parts shaped by vibration and vibrocompression, for example. However, the characteristics of CCW aggregates make it difficult to measure this type of concrete, since there are variations in the workability depending on the morphology and water absorption. The study of CCW aggregate is important because its use changes the concrete properties, especially in no slump concrete, due to the necessity to maintain the form immediately after the demolding. Therefore, the present work aim to evaluate the effect of the CCW aggregate on the no slump concrete characteristics, with the evaluation of the influence of the particle formation process and the pre-wetting of the aggregate on the rheological properties and the compression strength. For this, concrete compositions were studied using recycled aggregates with different contents of excess paste and different water/cement (a/c) ratios, in addition to the composition suggested by ABCP for concrete used in curb with natural aggregates. With the composition that presented the best results and with the reference mix design it was performed the analysis of the manufacturing cost of a piece of curb with each of the concretes, in order to evaluate the economic impact of the replacement of the aggregate. It was observed differences between the recycled and natural aggregates, both in relation to the properties and morphology, facts that resulted in different characteristics also in the concretes obtained. In the pre-wetting study, it was possible to observe that different pre-wetting rates resulted in different behaviors in both the fresh and hardened state, with a 60% variation in the compressive strength between 75 and 65% pre-wetting rates. By obtaining traces varying the excess of paste and a/c it can be observed that the composition with a/c of 0.35 and paste content of -5% was the one that resulted in better characteristics for the production of vibration pieces. Although this composition reached the minimum of 11 MPa required by standard for the production of curb, the cost for manufacturing a piece of concrete with recycled aggregate was 17% higher than the cost with natural aggregates, a result linked to the higher consumption of cement required by concrete with CCW to achieve the required strength.
Fantin, Marcel 1979. "Gestão de agregados minerais = análise e subsídios para políticas públicas." [s.n.], 2011. http://repositorio.unicamp.br/jspui/handle/REPOSIP/286775.
Full textTese (Doutorado) - Universidade Estadual de Campinas, Instituto de Geociências
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Resumo: Os impactos biofísicos e sociais causados pela mineração de agregados têm colocado este ramo da mineração no centro de situações de conflito, seja por causa do avanço da urbanização sobre áreas de mineração ou por causa de pressões da sociedade civil para impor restrições ao seu desenvolvimento. A busca de soluções para este problema tem exigido do poder público uma grande capacidade de conciliar os interesses divergentes e de assegurar o equilíbrio entre a oferta e a demanda por estes bens minerais. Para este fim, Política e Gestão desempenham um papel fundamental, pois estas são um instrumento eficaz de planejamento e ação. O objetivo desta tese é analisar e comparar experiências de políticas e gestão aplicada aos agregados minerais no Canadá e Brasil. Foram analisados os instrumentos dessas políticas, o desenho organizacional do Estado e o conflito entre o planejamento local e regional. Os resultados da pesquisa mostraram que os casos canadenses analisados são baseados em um forte planejamento provincial, que visa proteger os depósitos dos agregados minerais da esterilização, a fim de atender a demanda futura. Por outro lado, as províncias têm feito grandes esforços para garantir a recuperação de áreas degradadas pela mineração, utilizando, para isso, instrumentos econômicos, tais como cauções e seguros. Especialmente na Província de Ontário, a sua política de agregados minerais é mais eficiente em termos de seus principais objetivos e tem uma postura pró-ativa do setor de produção de agregados minerais. No entanto, seu foco não é o caminho do desenvolvimento sustentável. Para isso seria necessário alterar sua política baseada na garantia da oferta de agregados minerais por uma política baseada em uma gestão econômica da demanda. No Brasil, observou-se que, diferentemente do Canadá, a base legislativa do país permite uma participação muito pluralista das diferentes esferas de poder quando se trata de leis e elaboração de políticas ambientais para os agregados minerais. Entretanto, os resultados dessas políticas nos estudos de caso analisados têm sido bastante limitados devido a problemas como a falta de normas constitucionais que definam claramente as competências legislativas e materiais no âmbito federal, estadual e municipal. Tal situação tem levado à promulgação de leis contraditórias e ações desconexas entre os órgãos públicos responsáveis pela execução das políticas relacionadas com agregados minerais. Ainda, a falta de garantias para a recuperação de áreas degradadas pela mineração de agregados é um problema a ser resolvido a fim de garantir operações em sintonia com as modernas exigências ambientais
Resumé: Les perturbations biophysiques et sociaux causés par l'exploitation en carrière des granulats a placée dans le centre de scénarios de conflit, que ce soit en raison des progrès de l'urbanisation sur les ressources en granulats ou en raison de pressions de la société civile pour imposer des restrictions à leur développement. La recherche de solutions à ce problème a en outre demandé aux gouvernements public une grande habileté pour concilier les intérêts divergents et à assurer l'équilibre entre l'offre et la demande pour ces produits minéraux. À cette fin, la politique et la gestion jouent un rôle fondamental, car elles sont un outil efficace pour la planification et l'action. L'objectif de ce papier est d'analyser et de comparer leurs expériences de politiques appliquées aux granulats minéraux en provenance du Canada et du Brésil. Nous avons analysé les instruments de ces politiques, la conception de l'état d'organisation, le conflit entre la planification locale et régionale et les différences entre les points de vue de l'industrie et les intervenants. Les résultats de recherche illustré que les politiques canadiennes relatives aux granulats minéraux sont fondées sur une solide planification provinciale qui cherche à protéger les dépôts des granulats minéraux de la stérilisation afin de répondre à la demande future. D'autre part, les provinces ont fait de grands efforts pour assurer la réhabilitation des zones dégradées par l'exploitation minière, en utilisant, pour cela, des instruments économiques tels que les dépôts de garantie et les assurances. Ces politiques sont plus efficaces en termes de leurs principaux objectifs et ont a une posture pro-active du secteur de la production de granulats mineraux. Cependant, ce modèle a été vivement contestée par la société civile, surtout dans la province de l'Ontario, qui a pressé le gouvernement provincial de modifier l'approche traditionnelle de politique que qui se concentre sur le approvisionnement de granulats minéraux et la réhabilitation des zones dégradées pour une politique basée sur la conservation de l'environnement et la gestion de la demande de ces minéraux. Au Brésil, il a été observé que, contrairement au Canada, la base législative du pays permet une participation très pluraliste des différentes sphères du pouvoir quand il s'agit de l'élaboration de lois et de politiques pour les granulats mineraux. Cependant, les résultats de ces politiques ont été plutôt limités, malgré les efforts considérables déployés ces dernières années. Des problèmes tels que l'absence de règles constitutionnelles qui définissent clairement les pouvoirs législatifs et matériaux aux niveaux fédéral, étatique et municipal ont conduit à la promulgation de lois contradictoires et des actions disjointes entre les entités publiques chargées de la mise en oeuvre des politiques relatives aux granulats mineraux. Pourtant, l'absence de garanties pour le récupération des zones dégradées par l'exploitation minière des granulats est un problème être résolus afin d'assurer une extraction plus efficace et qu'il est en conformité avec les exigences environnementales modernes
Abstract: The biophysical and social disruption caused by aggregates mining has placed it at the center of conflict scenarios, either because of advancing urbanization on the aggregates resources or because of pressures from civil society to impose restrictions on their development. The search for solutions to this problem has required of the governments a large ability to reconcile the divergent interests and to ensure a balance between the supply and demand of these mineral goods. To this end, policy and management play a fundamental role, since they are an efficient tool for planning and action. The aim of this thesis is to analyze and compare experiences of policy and management applied to mineral aggregates in Canada and Brazil. We analyzed the instruments of these policies, the state organizational design and the conflict between the local and regional planning.The research results showed that the Canadian policies related to mineral aggregates are based on a strong provincial planning that seeks to protect the deposits of mineral aggregates from sterilization in order to meet future demand. On the other hand, the provinces have made great efforts to ensure the rehabilitation of areas degraded by mining, using, for this, economic instruments such as deposits and insurances. Such policies are more efficient in terms of their main goals and have a pro-active posture of the mineral aggregates producing sector. However, this model has been hotly contested by civil society, especially in the Province of Ontario, which has pressed the provincial government to change the traditional policy approach that focuses on the provision of mineral aggregates and the rehabilitation of degraded areas to a policy based on environmental conservation and the management of demand for these mineral inputs. In Brazil, it has been observed that, unlike Canada, the country's legislative basis allows a very pluralistic participation of the different spheres of power when it comes to drafting laws and policies for mineral aggregates. However, the results of these policies have been rather limited, despite the great efforts made in recent years. Problems such as the lack of constitutional rules that clearly define the legislative and materials powers at the federal, state and municipal levels have led to the enactment of conflicting laws and disjointed actions between the public entities responsible for the implementation of policies related to mineral aggregates. Still, the lack of guarantees for the recovery degraded areas by aggregates mining is a problem to be faced in order to ensure a more efficient extraction and that it is in line with modern environmental requirements
Doutorado
Geologia e Recursos Naturais
Doutor em Ciências
Macioski, Gustavo. "Estudo da álcali-ativação de pó de blocos cerâmicos com cal hidratada." Universidade Tecnológica Federal do Paraná, 2017. http://repositorio.utfpr.edu.br/jspui/handle/1/2389.
Full textCeramic materials from bricks and tiles present in construction waste are considered contaminants in the production of recycled aggregates, as they have a low compressive and impact strength, as well as high porosity. These characteristics make mortars and concretes produced with mixed recycled aggregates have low compressive strength and high water absorption due to the porosity of the recycled aggregates. As an alternative to the technological use of this type of material, the ceramic has been studied as an alkali-activation raw material, either by direct combination with hydrated lime or as an addition to Portland cement (pozzolan reaction). The aim of this work is to study the alkali-activation of ceramic bricks powder with hydrated lime, aiming binding properties. For this, the study was carried out in three stages: evaluation of the reactivity of the ceramic bricks powder as a function of the burning temperature; evaluation of the reactivity of the ceramic bricks powder as a function of the particle distribution; and the evaluation of the alkaliactivation reaction kinetics as a function of the SiO2/CaO molar ratio, as well as the cure method. From the results obtained, it was observed that the reactivity of the ceramic bricks powder is influenced by the burning temperature of the clay and the size of the particles. The commercial ceramic bricks did not meet the physical requirements to be classified as pozzolan, obtaining in the Chapelle test the value of 305 mg of Ca(OH)2 fixed by gram of pozzolan and 5.5 MPa of compressive strength with lime in the IAP test. The addition of Ca(OH)2 in the ceramic bricks powder whose SiO2/CaO molar ratio was 2.75 gave the highest compressive strength when cured at 77 °C and 90% of relative humidity, reaching 8.5 MPa at 28 days. In the course of the alkali-activation reaction of the ceramic bricks powder, it was observed low hydration heat and accelerated portlandite consumption. At the end of the reaction it was possible to determine calcium silicate and aluminum silicate hydrated phases by X-ray diffraction and reticular morphologies by the scanning electron microscopy.
Silva, Patricia Ribeiro da. "Influência de adições minerais e aditivo impermeabilizante interno no desempenho de telhas protendidas pré-fabricadas em concreto." Universidade Tecnológica Federal do Paraná, 2011. http://repositorio.utfpr.edu.br/jspui/handle/1/317.
Full textWith the emerging precast concrete technology, the civil construction has acquired high agility, reducing construction time and greater quality control in execution. Among several precast pieces, tile in prestressed concrete is characterized by selfsupporting spans of up to 25 m, without the existence of an intermediate support structure. Being a slim product, requires an improvement in increasing the durability of the structure because of the steel corrosion and maintain their fitness for use. The objective of this research is to reduce the permeability of the precast tiles, and analyzing their influence in the durability of the concrete face of the aggressiveness classes constants in the NBR 9062/2006, that establish the a/c ratio up to 0,45 and minimum compressive strength characteristic of 40 MPa, positioning themselves as a class of environmental aggressiveness II - Urban. For this, were selected a few mineral admixture from Curitiba/Paraná and a waterproof internal admixture, comparing with the concrete mix pre-existing in production line. The concrete dosages were defined by packing particles and were analysed for mechanical compressive strength, water absorption by immersion and by capillarity and water penetration under pressure, in addition to tests of mercury intrusion porosimetry (MIP), carbonation and chloride ion penetration. About the mechanical compressive strength, the dosage reference showed the best results (due to lower water / cement ratio and higher cement consumption), followed by concrete with waterproofing admixture and metakaolin. For water absorption, all measurements fall as durable concrete, especially the metakaolin additive and filler + waterproofing. For the water absorption, all dosages presented low permeability. For the water penetration under pressure all fall as impervious to several conditions, especially with metakaolin and waterproofing admixture. The MIP test shows that the dosage with filler has a higher concentration of pores and the dosage with metakaolin has the smallest maximum diameter of pores, with a tendency towards refinement in smaller diameters. When analyzing the carbonation, the metakaolin showed the best results, allowing a smaller reinforcement cover for a lifetime of 50 years. As the penetration of chlorides ions, the metakaolin, showed a greater reduction comparing with other dosages for its pozzolanic activity, contributing to the concrete durability. In general, it is possible to improve the concrete impermeability with the addition of 8% of metakaolin by weight of cement, with 5,2% of cement reduction, showing good results also using 1% of waterproofing admixture. As for durability, the optimizing of aggregates granulometric curve and the use of metakaolin enables the use of prefabricated tiles in regions of class of environmental aggressiveness III - Industrial or Marine, observing the minimum concrete cover of reinforcement.
Beltrame, Neusa Aparecida Munhak. "Comportamento do cimento álcali ativado em ambientes sulfatados." Universidade Tecnológica Federal do Paraná, 2017. http://repositorio.utfpr.edu.br/jspui/handle/1/3031.
Full textPortland cement (PC) is an industrialized product that is not so consuming of energy and raw materials, but also responsible for large CO2 emissions. Besides the environmental impact, the presence of some hydrated compounds that in contact with the sulfates, produce expansive phases that reduce the useful life of the structures. Minerals additions, such as blast furnace slag, have been added to reduce clinker and increase resistance to sulphates, but not all slags confer employability as addition because of their chemical composition. Cements with additions show very low resistance gain in the early ages, making it uninteresting for the productive chain of civil construction. Thus, the limitations that PC presents, together with the increase of residues, have encouraged the search for clinker-free binders. Alkali-activation provided the possibility of reuse of several by-products, because the reaction kinetics is similar to PC, due to chemical similarity and heat release. Researches related to the durability of alkaliactivated cements (AAC) are still very low, mainly the efficacy of the methods used to evaluate the resistance to sulfates in laboratory environments. Therefore, the objective of this work was to investigate the behavior of slag pastes activated with 5% NaOH and sulfate resistant PC (PCIV-SR) in sulphated environments using the NIST method and to compare with the accelerated mortar method proposed by NBR 13583:2014. The evaluations included microstructural analysis (XRD/SEM/DTG) and macrostructural analysis through visual inspection, dimensional variation, mass variation and compressive strength. The results indicated that under the conditions tested, the accelerated methods of sulfate resistance evaluation did not present significant differences between pastes and mortars. The AACs presented better performance before and after exposure to Na2SO4 compared to PCPIV-SR, favoring hydration and compressive strength. On the other hand, the formation of gypsum appears to be the main degradation product of the AACs in the MgSO4 solution, caused by the C-S-H decalcification, strongly affecting the physical, chemical and mechanical properties of the activated alkali cements.
Cardoso, José Ribamar de Abreu. "Uso do agregado de entulho da construção civil de Manaus - AM para obtenção de bloco de argamassa celular." Universidade Tecnológica Federal do Paraná, 2010. http://repositorio.utfpr.edu.br/jspui/handle/1/184.
Full textNa construção civil tem-se procurado mecanismos por meio de novas técnicas que possibilitem viabilizar a sustentabilidade dessa atividade produtiva, espeitando às questões ambientais e a tendência de escassez dos recursos naturais. A indústria da construção civil tem buscado na reciclagem dos resíduos de construção e demolição (RCD) uma forma de atenuar o impacto ambiental e buscar uma fonte alternativa de matéria-prima. Associado a essa preocupação, grandes centros consumidores da região Amazônica, como Manaus, utilizam agregados para produção de concretos e argamassas minerados dos leitos dos rios e trazidos de grandes distâncias. O presente trabalho tem como objetivo estudar a obtenção de blocos de argamassa celular para alvenarias, utilizando agregados de RCD em substituição aos agregados convencionais. Os blocos de argamassa celular são largamente utilizados na Europa como elementos de alvenaria devido à capacidade de isolamento térmico e acústico, parâmetros esse de grande relevância para um elemento construtivo também em regiões de clima quente. Em Manaus existem empresas que constroem habitações com argamassa celular monolítica, ou seja, todas as alvenarias da residência são moldadas em uma única etapa. Assim, após obtenção e caracterização da fração cinza de RCD, foi utilizada uma composição comercial de argamassa celular para analisar a substituição dos agregados alternativos pelo RCD. Com isso buscou-se também obter uma dosagem mais econômica, com resistência mecânica exigida pela norma brasileira para blocos e minimizar o impacto ambiental de argamassas celulares convencionais. Os resultados técnicos foram favoráveis, com potencial para consumir agregados de RCD, contribuindo assim na gestão ambiental desse resíduo da construção civil.
In building construction, we have searched for mechanisms through new technologies which enable the sustainability of this productive activity, respecting the environmental issues and the shortage of natural products. Civil construction industry has searched for construction and demolition recycling (RCD) as a way of mitigating the environmental impact and a way of seeking for an alternative source of raw material. Associated with this concern, large consumer centers in the Amazon region, such as Manaus, have been using aggregates to produce concrete and mortar mined from the riverbeds and brought from great distances. This work aims to study the acquisition of blocks of masonry mortar cell, using clusters of RCD as a substitute for conventional aggregate. The blocks of mortar cell are widely used in Europe as masonry units due to their thermal and acoustic isolation abilities, which constitute very important parameters for building elements in warm climates. In Manaus, there are companies that build houses with mortar and monolithic cells, i.e., all the walls of the residence are molded in a single step. Thus, after obtaining and characterizing the ash fraction of RCD, we used a commercial composition of mortar cell to analyze the substitution of the alternative aggregates by RCD. With this procedure we searched to obtain a more economic dosage with the strength required by the Brazilian standard blocks and minimize the environmental impact of conventional mortar cells. The technique results were positive, with the potential of consuming RCD aggregates, thus contributing to the environmental management of this civil construction waste.
Baliso, Unathi. "Partnering with suppliers for quality improvement." Thesis, Cape Peninsula University of Technology, 2010. http://hdl.handle.net/20.500.11838/1232.
Full textUneven surfaces on national roads that often lead to difficulty and even danger can be extremely hazardous when wet, due to mud and cracks, and also create dust pollution for motorists, pedestrians, residents and business. The continuing use of low quality raw materials in producing hot mix asphalt for national roads, leads to regular maintenance at a very high cost. The quality aggregates (stone that is used to produce asphalt), and the quality of bitumen are often inadequate for the correct composition of hot mix asphalt. The mst important factors affecting initial and long term performance of the highways is the inferior pavement structure and condition, due to poor aggregates (raw material)from suppliers. The performance of asphalt i s largely determined by the characteristics of its constituents, the asphalt binder and aggregates.
Soares, Raimundo Nonato Belo. "Resíduo de construção e demolição e EPS reciclado como alternativa de agregados para a Região Amazônica: aplicação em blocos para alvenaria." Universidade Tecnológica Federal do Paraná, 2010. http://repositorio.utfpr.edu.br/jspui/handle/1/185.
Full textFinanciado pela CAPES e pela SUFRAMA.
No estado do Amazonas a questão do gerenciamento dos Resíduos de Construção e Demolição (RCD) merece atenção e soluções que sejam sustentáveis dos pontos de vista ambiental, econômico e social. O RCD gerado, bem como o Poliestireno Expandido (EPS), ainda são descartados ou conduzidos às lixeiras com os agravantes da inexistência de um projeto de gestão, visto haverem problemas com inundações, poluição dos mananciais e, significativa ocupação nos lixões controlados pelo poder público, dentre outros. Outro aspecto relevante refere-se ao uso, pela construção civil, de agregados como o seixo rolado e granito, o primeiro extraído de rios e transportado em balsas percorrendo distâncias superiores a 700 km e o segundo explorado a distâncias superiores a 150 km da cidade de Manaus, causando alto impacto ambiental e elevado custo de logística. Neste contexto, o objetivo desse trabalho foi estudar a viabilidade técnica da produção de concreto alternativo utilizando RCD e EPSR(Poliestireno Expandido Reciclado) obtido após processo de extrusão e moagem na forma de agregado graúdo ou miúdo. Os RCDs (de concreto) selecionados em obras e britados, bem como, o EPSR foram analisados granulometricamente com a finalidade de serem incorporados à concretos aplicados a fabricação de blocos de alvenaria. Os blocos produzidos foram analisados quanto a resistência mecânica e também quanto à absorção de água. O EPSR possui baixa densidade e contribui para a obtenção de blocos mais leves.
In the Amazon State, the issue of management concerning construction and demolition waste (C&D) deserves attention and solutions that are sustainable from environmental, economical and social standpoints. The RCD produced as well as the expanded polystyrene (EPS), are still discharged in inappropriate places or taken to the dumpsters with the worsening provided by the lack of a management project such as: floods pollution of the water resources (rivers lakes and others) and significant space occupation in the landfills controlled by the city council, among others. Another aspect, related with the civil engineering sector, refers to the usage of components like the pebbles and granite, the first one extracted from rivers and transported by ferries within distances over 700 km and the second one explored within distances over 150 km from Manaus City, causing high environmental impact and high logistics cost. The goal of this research was to study the technical feasibility of producing alternative concrete using RCD and post-consumpting EPS extruded and crushed to transform it in aggregate. The RCDs (of concrete) selected in construction sites and crushed, as well as the EPSR (expanded polystyrene recycled) were analyzed in its granulometric distribution to be used as aggregate on the concrete composition features to obtain wall blocks. The produced blocks were analyzed mechanically and also regarding the water absorption level. The EPSR has low density and contributing to the production of lighter blocks.
5000-11-25
Cortas, Rachid. "Nouvelle approche expérimentale pour la maîtrise de la fissuration du béton jeune : influence de la nature et de la saturation des granulats." Doctoral thesis, Universite Libre de Bruxelles, 2012. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209672.
Full textvérifiée. Un nouveau dispositif expérimental a été développé dans le but de mieux décrire l’évolution de la résistance et de la capacité de
déformation en traction du béton jeune. Les indicateurs globaux (macroscopiques) apparaissent plus sensibles que les indicateurs de la microstructure pour rendre compte des différences de comportement observées. L’évolution du module élastique, du retrait plastique et endogène corrélées à l’évolution de la capacité de déformation et de la résistance en traction permettent de mieux caractériser le risque
potentiel de fissuration par retrait empêché. La fin de prise correspond à une phase critique. L’influence de la saturation des granulats est
indirecte, et résulte des variations du rapport Eau d’ajout/Ciment, à rapport Eau efficace/Ciment constant. La nature des granulats intervient au niveau des évolutions relatives de la résistance en traction et du module élastique. La méthodologie peut être appliquée à l’étude d’autres types de bétons et d’autres paramètres de formulation.
Doctorat en Sciences de l'ingénieur
info:eu-repo/semantics/nonPublished
Mellon, P. "An investigation of altered basalts used for road aggregate in Ethiopia." Thesis, University of Hertfordshire, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.355854.
Full textHermann, Aline. "Empacotamento de agregados reciclados para concretos vibrocompactados." Universidade Tecnológica Federal do Paraná, 2016. http://repositorio.utfpr.edu.br/jspui/handle/1/1846.
Full textOs agregados reciclados vêm sendo amplamente estudados e utilizados em diversos campos da engenharia civil. Dentre suas aplicações mais comuns pode-se citar: argamassas de revestimento, bases, sub-bases e subleito de pavimentos, elementos pré-moldados de concreto, obras de contenção e aterros. O principal fator que dificulta a utilização do agregado reciclado em concretos está relacionado à capa de argamassa aderida à superfície. Esta capa tem elevada porosidade e consequentemente elevada absorção de água, o que proporciona ao concreto, menor trabalhabilidade, além do aumento do consumo de superplastificantes e de água, que por sua vez aumenta o consumo de cimento a fim de garantir a resistência mecânica à compressão. Estes fatores elevam o custo do concreto. O empacotamento de partículas, entre outros aspectos, estuda a adequada distribuição granulométrica e morfologia das partículas, bem como a incorporação de aditivos e adições minerais de modo que o índice de vazios seja o menor possível e a trabalhabilidade ideal para o concreto com determinada aplicação. O ajuste adequado desses parâmetros permite um aumento da resistência mecânica à compressão do concreto com o mesmo consumo de cimento ou, mantém a resistência com redução no consumo de cimento. Assim, o objetivo deste trabalho é aplicar técnicas de empacotamento em agregados reciclados de concreto, a fim de avaliar a efetividade dessa ferramenta na definição de traços de concretos secos utilizados em blocos para pavimentação com resistência mecânica à compressão maior que 35 MPa. Para isso, os agregados reciclados da construção civil, produzidos por diferentes equipamentos de 4 diferentes empresas localizadas em um raio de 100 km da cidade de Curitiba – PR, foram caracterizados quanto a: morfologia, distribuição granulométrica, massa específica, massa unitária, índice de vazios, composição mássica e visual, além de absorção de água. Em seguida, foi escolhido o agregado que apresentou características físicas mais propícias ao melhor empacotamento, com base na morfologia, na distribuição granulométrica e nos valores de: absorção de água, massa unitária e específica. Escolhido o agregado aplicou-se dois modelos de empacotamento de partículas: o de Funk e Dinger (Alfred) de 1980 e o de De Larrard de 1999, com e sem a introdução do cimento na análise granulométrica. Com as proporções ideais dos agregados foi então estudado, por meio do consistômetro “VeBe”, a quantidade de água para cada traço de concreto. As composições que apresentaram os melhores resultados foram testadas quanto à absorção de água, resistência mecânica à compressão axial e à tração por compressão diametral e análise microestrutural por Microscópio Eletrônico de Varredura. Os concretos foram moldados por meio da mesma vibrocompactadora de laboratório utilizada por Lima (2009), a qual consiste de uma mesa vibratória e cilindros de aço aplicados sobre os moldes, para simular a força de compactação de vibrocompactadoras industriais. Dentro do desvio padrão considerado, o modelo de empacotamento de Funk e Dinger com a introdução do cimento na análise granulométrica apresentou os melhores resultados em relação a resistência à compressão aos 28 dias e em relação a absorção de água. Um tempo de vibrocompactação em laboratório equivalente ao de máquinas industriais foi determinado. Além disso, com o mesmo consumo de cimento, concretos com agregados reciclados alcançaram resistências mecânicas dentro do desvio padrão de concretos produzidos com agregados naturais, utilizados por indústrias de pré-moldados.
Recycled aggregates have been widely studied and used in some areas of civil engineering. Among its most common applications can include: revetment mortar, bases, sub-bases, and subgrade pavements, precast concrete elements, containment works and landfills. The main factor that hinders the use of recycled aggregate in concrete is related to the mortar layer adhered to the surface. This layer has high porosity and therefore high water absorption, which gives the concrete, lower workability, and increased content of superplasticizers and water, which in turn increases the consumption of cement in order to ensure the compressive strength. These factors increase the cost of the concrete. The particles packing, among other things, studying the proper particle size distribution and particle morphology, as well as the incorporation of additives and mineral additions such that the voids content is minimized and optimum workability to concrete with particular application. Proper adjustment of these parameters allows an increase mechanical strength of the concrete with the same cement content or, maintains the strength with reduction in the cement content. Thus, the objective of this work is to apply particles packing techniques in recycled concrete aggregates in order to evaluate the effectiveness of this tool in the dry concrete compositions used in paving blocks with compression mechanical strength to greater than 35 MPa. For this, the recycled concrete aggregates produced by different equipment of 4 different companies located within a radius of 100 km from the city of Curitiba - PR, were characterized for: morphology, particle size distribution, density, bulk density, void ratio, mass and visual composition and water absorption. Then, it was chosen the aggregate more favorable physical characteristics to the best packing, on the basis of morphology and the particle size analysis and the values of: water absorption, density and bulk density. Chosen the aggregate particles was applied to two packing packing models: Funk and Dinger (Alfred) of 1980 and De Larrard of 1999, with and without the introduction of cement in particle size distribution. With the ideal proportions of aggregates were then studied by means of consistometer "VeBe", the amount of water for each concrete mix. The compositions that showed the best results were tested for water absorption, mechanical resistance to axial compression, tensile strength by diametrical compression and microstructural analysis by Scanning Electron Microscope. The concrete was cast by the same laboratory vibro-compression machine used by Lima (2009), which consists of a vibrating table and steel rollers applied on the molds, to simulate the compaction force of industrial vibro-compression machine. Within the standard deviation considered the packing packing model of Funk and Dinger with the introduction of cement particle size analysis showed the best results with respect to compression strength at 28 days and for the absorption of water. A lab equivalent time of vibro-compression to industrial machines can be found and this time becomes greater when using recycled aggregates. Moreover, with the same consumption of cement concrete with recycled aggregates achieved mechanical strength within the standard deviation of concretes produced with natural aggregates used by precast industries.
Okeyinka, Oriyomi M. "The applicability of recycled waste paper as lightweight building materials." Thesis, University of Wolverhampton, 2016. http://hdl.handle.net/2436/620495.
Full textThiam, Moussa. "Development and Engineering Properties of Construction Materials Made Using Melted Plastics Wastes as the Only Binding Phase." Thesis, Université d'Ottawa / University of Ottawa, 2021. http://hdl.handle.net/10393/42638.
Full textSilva, Geovani Almeida da. "Recuperação de blocos de coroamento afetados pela reação álcali-agregado." Universidade Católica de Pernambuco, 2007. http://www.unicap.br/tede//tde_busca/arquivo.php?codArquivo=161.
Full textThe alkali-aggregate reaction affects the durability and the mechanical resistance of the concrete structures, provoking cracks in the structural elements. Despite of these pathological manifestations, it cannot affirm that, even so the reaction is slow, the ultimate limit state cannot be reached. The occurrence of this phenomenon on blocks foundation is rarely described in literature. Recently was identified in foundations of buildings in the Metropolitan of Recife Region, constituting a problem that comes calling the attention of the community technique and the productive sector of civil construction. The pile caps affected by the AAR must suffer interventions with adequate techniques of recovery to each situation. Inside of that focus, this work presents the results of the attendance of the services of microcement injection in cracks in the blocks of a building in recovery process. It still presents the reinforcement proposal for the pieces of infrastructure affected by expansible reaction. To go accomplished extractions of specimens, cleaning and superficial closing of the cracks with an epoxy mixture and kaolin, application of the microcement inside the cracks and extraction of specimens after the injection for verification of the effectiveness of the fulfillment of the cracks with the injected material. The results can supply important subsidies for repair pile caps damaged for the action of AAR
Parks, L. F. "A study of Kuwait marine clay and its suitability for production of synthetic aggregate and other building materials." Thesis, Brunel University, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.370679.
Full textPourakbar, Sharifi Naser. "Application of Phase Change Materials to Improve the Thermal Performance of Buildings and Pavements." Digital WPI, 2017. https://digitalcommons.wpi.edu/etd-dissertations/22.
Full textEl, boukhari Mohamed. "« Analyse expérimentale du comportement mécanique et thermiqued'un béton et d'un mortier allégés par des grignons d'olives : Application au bâtiment »." Electronic Thesis or Diss., Reims, 2023. http://www.theses.fr/2023REIMS040.
Full textThe management of agricultural waste and the promotion of sustainable building materials offer many considerable benefits. By integrating sustainable practices into the construction sector, we have the ability to reduce our ecological footprint by limiting the excessive exploitation of natural resources. The research conducted in this study aims to develop a lightweight structural concrete and cement mortar using organic olive pomace aggregates. Two types of aggregates were used, depending on whether they were mixed with or without olive mill wastewater. The main objective of this study is to experimentally evaluate the mechanical and thermal properties of lightened concrete and mortar specimens in comparison with ordinary concrete and mortar specimens. They were prepared using dry and saturated olive pomace aggregates, with a percentage substitution of natural sand ranging from 0% to 15%. The results showed that the optimal formulation for producing lightweight concrete consists of 5% dry olive pomace aggregates mixed with olive mill wastewater. This formulation offers better mechanical properties, including a compressive strength of 25 MPa, a tensile strength of 4.61 MPa, and a dynamic modulus of elasticity of 44.39 GPa. Additionally, the resulting material has a reduced dry bulk density, leading to a decrease of approximately 5.69% compared to the reference concrete. For cement mortar, the best results were obtained with a mixture containing 5% dry olive pomace aggregates mixed with olive mill wastewater. The results showed a marginal effect on compressive strength (Rc), reaching 33.50 MPa after 28 days of curing. However, for both concrete and mortar, microstructural analysis revealed weak adhesion between olive pomace aggregates and the cement matrix at the Interfacial Transition Zone. Experimental tests also showed that increasing the content of olive pomace aggregates reduces the ultrasound propagation velocity and the dynamic modulus of elasticity of lightweight concrete and mortar, as well as their workability, while increasing their porosity.As regards the thermal properties of the developed materials, the incorporation of olive pomace aggregates led to an improvement in thermal resistance. In the case of lightweight concrete with 5% of dry olive pomace aggregates mixed with olive mill wastewater, the thermal conductivity (λ) decreased from 1.3 W/m·K (for the control specimen) to 0.86 W/m·K. In the case of cement mortar containing 5% of dry olive pomace aggregates mixed with olive mill wastewater, the thermal conductivity (λ) decreased from 1.1 W/m·K (control specimen) to 0.87 W/m·K. In conclusion, this study revealed that the materials developed and tested under laboratory conditions meet the required standards for general use in construction
Souza, Adriana Aparecida Ambrosio de 1975. "Influencia do tipo de agregado nas propriedades mecanicas do concreto submetido ao fogo." [s.n.], 2005. http://repositorio.unicamp.br/jspui/handle/REPOSIP/258724.
Full textDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo
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Resumo: Este trabalho trata da influência do tipo de agregado nas propriedades mecânicas do concreto não armado, quando submetido a temperaturas elevadas, avaliando as prováveis alterações na resistência à compressão, resistência à tração e no módulo de elasticidade. Apresenta-se um estudo experimental da influência dos três agregados escolhidos, argila expandida, basalto e calcário no comportamento do concreto submetido às temperaturas de 300°C e 600°C. Moldaram-se corpos-de-prova com os agregados escolhidos, utilizando misturas usuais da região de Campinas - SP, de dimensões 10cm x 20cm, onde procurou-se manter como parâmetro fixo a relação água/cimento para as três misturas. Através das propriedades mecânicas procurou-se avaliar o efeito do resfriamento rápido e lento após aquecimento, e a provável recuperação das mesmas pelo processo de reidratação do concreto. A reidratação foi feita com parte dos corpos-de-prova imersos em água, parte envolvida em filme plástico e parte exposta à temperatura e a umidade ambiente. Os ensaios para avaliar a resistência à compressão, a resistência à tração e o módulo de elasticidade, foram realizados para as idades de 7, 28, 56 e 112 dias. Os resultados obtidos, de maneira geral, comprovaram o decréscimo nas propriedades mecânicas avaliadas, indicado por normatização internacional em situação de incêndio. Foi comprovado o efeito prejudicial do resfriamento rápido e, por outro lado, foi quantificada a recuperação nas propriedades mecânicas avaliadas, provenientes da reidratação. Os resultados desta pesquisa, em sua grande maioria, são inéditos e serão de grande valia ao meio técnico nacional, carente de informações deste tipo.
Abstract: This work deals with aggregate types influence in mechanical properties of the concrete submitted to high temperatures, evaluating the probable alterations to compression and tension resistances and elasticity module. An experimental study of the three chosen aggregates influence is presented, expanded clay, basalt and limestone in the concrete behavior submitted to 300°C and 600°C temperatures. Samples were molded with the chosen aggregates, using usual mixtures in the region of Campinas -SP - Brazil with 10cm x 20cm dimensions, where it was maintained as a fixed parameter, the water-cement relation for the three mixtures. Through mechanical properties, the effect of quick and slow cooling after the heating, and their probable recuperation by the concrete re-hydratation process is evaluated. The re-hydratation was done with part of samples immersed in water, and part of it evolved in plastic and the other part exposed to room temperature and moisture. The tests to evaluate mechanical properties were accomplished for the ages of 7, 28, 56 and 112 days. The results proved the decrease in mechanical properties, tensile strength, compressive strength and modulus of elasticity, indicated in international standards to concrete behavior under fire effect. It was showed the injurious effect of cooled rapdly and on the other hand, it was evaluated the re-hydratation contribution in residual mechanical properties. The results of this study are previously unpublished and they will be important for means of technical, lacking of these informations.
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