The work is focused on the possible use of secondary raw materials of the energy industry in the construction industry, particularly in concrete applications, where as the main raw material of the binder composition are used solid fluidized bed combustion residues - filter and ground. The aim of this work is to prepare concrete or concretes based on solid residues from fluidized bed combustion, that will fulfill or at least approximately approach by their parameters to commonly used concretes based on portland cement. The experimental part is divided into several chapters, at first the results of analyzes of feedstock and solid residues from fluidized bed combustion, portland cement and calcium hydroxide. Other chapters describe proposals for alternative binders, concrete, characterization and testing. Mainly were observed changing properties of the prepared concretes by changing the ratio of binders and aggregates. In tests were evaluated mainly mechanical properties and phase composition.

This work focuses on the possibility of using recycled glass in the manufacture of blended portland cements. It examines the possibilities to improve pozzolanic properties of recycled glass with new milling processes, the formation of agglomerates material during the course of grinding and their subsequent effect on the hydration process of binders. It is also the optimization of the grinding process with respect to the wear of grinding bodies, grinding energy consumption and maximize the performance of the mill.

The focus of this research is to characterize the risk of carbon sequestration under downhole conditions with regards to wellbore cement integrity. The primary research objective was to understand the geochemical interactions of simulated sequestration brines and wellbore cement. There are four key focuses of this study with regards to cement interaction: 1) Simulated brines saturated with Supercritical CO2 and CO2-O2; 2) Adjacent formation host rock under sequestration conditions; 3) Geochemical modeling using CHIM-XPT based on the experimental studies of points 1) and 2) above; 4) Geomechanical strength tests of CO2 exposed cements. First, the interaction of cement with supercritical CO2, CO2-saturated brines, and CO2-O2 mixtures at 50 °C, 85 °C, and 28.9 MPa was evaluated. Cement exposed to a lower salinity brine (1 M) had a larger alteration depth (1.25 mm) compared to cement exposed to a higher salinity brine (2.2 M) (0.836 mm). CO2-O2 exposed cements displayed alteration depths of 1.6 mm at 85 °C and 0.7 mm at 50 °C for 1 M. The cement exposed to the 2.17 M solution had an alteration extending 1.685 mm. The second focus studied the influence of adjacent formations and observed mineral trapping in the Grande Ronde Basalt-cement. Studies of Mt. Simon Sandstone-cement interaction provided evidence for high CO2 storage capacity. The third focus is geochemical modeling using CHIM-XPT. Pure CO2 saturated brines yielded a pH of 3.0 at 1 M and 3.85 at 2.17 M. The CO2-O2 gas run calculated a pH of 3.96 at 1 M and 3.85 at 2.17 M. The Pasco solution after exposure had a pH of 6.97 and an estimated dissolved 161 g of CO2 (g). The pH of the Illinois Basin brine and Mt. Simon sandstone [and cement paste] was 5.8 with an estimated 139 g of CO2 consumed. Lastly, geomechanical tests on CO2 exposed cements indicated that addition of oxygen or changes in temperature play a key role in compressive and tensile strength, decreasing strength by 20-35%. This research highlighted the importance of representing the in-situ wellbore environment when conducting laboratory experiments. This dissertation includes previously published and unpublished co-authored material.

New trademarks appear on the dental market every year and it is difficult to determine whether they should be used in clinical praxis or not. Numerous studies have been carried out to investigate different types of materials, trying to declare which material is best suited for a certain type of restorations. The study objective was to investigate if there are any differences in the shear bond strength between a self-adhesive cement and an yttrium oxide-stabilized zirconium dioxide (Y-TZP) and a dental cobalt-chromium alloy (Co-Cr).  The null hypothesis was used. The hypothesis was that the shear bond strengths was the same when cementing the adhesive cement to the dental Co-Cr alloy and the yttrium oxide-stabilized zirconium dioxide. Twenty plastic embedded samples were used in this study, 10 specimens of Co-Cr alloy, and 10 specimens of Y-TZP. The cement was applied, and the specimen were stored in water of 37°C for 24 hr. The tests were performed with an UltraTester™ with the speed of 1 mm / min to measure the shear bond strength (SBS) between the adhesive cement, the Y-TZP and the Co-Cr alloy. The values where then registered. The mean value of the shear bond strength for adhesive cement and Y-TZP was 23.5 MPa, and for Co-Cr alloy 22.8 MPa. No significant difference in shear bond strength were found between the adhesive cement and the Y-TZP and the Co-Cr alloy, after being stored in water for 24 hrs, p > 0.05.

Made available in DSpace on 2015-12-10T14:22:58Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-07-31. Added 1 bitstream(s) on 2015-12-10T14:29:13Z : No. of bitstreams: 1 000854214.pdf: 2053071 bytes, checksum: 26fbb318c26a7f6004c27be21f798af1 (MD5) / Este trabalho de pesquisa apresenta um estudo sobre a influência da Cinza de Casca de Arroz - CCA e da cal no comportamento do Solo Cimento Auto-Adensável - SCAA no estado fresco e endurecido, e um estudo preliminar sobre a reologia do SCAA e sua relação com o fator água/cimento. Foram adotadas 18 misturas de SCAA, variando-se as quantidades de água, cimento, CCA, cal e superplastificante, utilizando parâmetros adequados como base de estudo. A proposta principal visa analisar a ação de materiais pozolânicos e hidráulicos na mistura de SCAA, nas condições de trabalhabilidade no estado fresco, e na evolução de sua resistência ao longo do tempo. No estado fresco, foram realizados ensaios de espalhamento slump flow, ensaio do Funil e ensaios de segregação por peneiramento; no estado endurecido, corpos-de- prova cilíndricos de 5 cm de diâmetro e 10 cm de altura foram submetidos a ensaios de resistência à compressão mecânica e absorção de água aos 7, 28, 56 e 84 dias. Observou-se que, no estado fresco, para o maior teor de cimento adotado no estudo, a mistura mostrou uma diminuição de trabalhabilidade com a adição de CCA. No estado endurecido, foi observado uma diminuição da absorção e um crescimento da resistência mecânica à compressão com os teores de cimento, de CCA, de cal, e dos dois conjuntamente. A ação benéfica da CCA na resistência mecânica a compressão aumentou, em geral, com o teor de cimento na mistura, e através do tempo a partir de 28 dias de cura. Uma diminuição desta ação é visível a partir de 84 dias de cura. Foram alcançados, aos 28 dias de cura, tensões limites de 7,99 MPa para as misturas sem adições, e de 11,45 MPa com adjunção de 10% de CCA em relação com a massa de cimento. O estudo adicional que foi realizado durante essa pesquisa teve como proposta a análise do comportamento reológico do SCAA fresco para três das... / This paper present a study about the influence of Rice Husk Ash - RHA and lime on the behaviour of Self-Compacting Soil Cement - SCSC at fresh and hardened state, and a preliminary study about the rheology of SCSC and its relationship with the water-cement ratio. 18 mixes were made by varying the amounts of water, cement, RHA, lime and superplasticizer, using appropriate parameters as a baseline. The main proposal aims to analyze the action of pozzolans and hydraulic materials in the SCSC mixtures, on workability conditions at fresh state, and on compressive strength over time. Slump Flow, Funnel and Segregation tests were performed at fresh state. At hardened state, cylindrical specimens of 50 mm diameter and 100 mm height, were subjected to unconfined compression test and water absorption test after 7, 28, 56 and 84 days. It was observed that, at fresh state, for the higher cement content adopted in this study, the mixture showed a decrease in workability with the addition of RHA. At hardened state, the material showed a decrease in absorption and an increase in compressive strength with cement, RHA and lime contents, and with the addition of RHA and lime together. The beneficial action of CCA on the strength of SCSC increased, on average, with the cement content in the mix, and through time from 28 days of curing. A decrease of that action is visible at 84 days of curing. After 28 days of curing, ultimate tensile strength of 7.99 MPa for mixes without additions, and 11.45 MPa with ratio CCA:cement of 1:10. In the additional study related in this paper, the rheological behavior of fresh SCAA developed in the study was analyzed. Three mixes, without addition, were chosen within the 18 mixes of the main study with the purpose of observing the water-cement ratio influence. The additional study adhered to the determination of the rheological model - representing the behavior of the fresh material ...

Made available in DSpace on 2014-06-11T19:31:26Z (GMT). No. of bitstreams: 0 Previous issue date: 2005Bitstream added on 2014-06-13T18:42:03Z : No. of bitstreams: 1 alencarjunior_ea_dr_arafo.pdf: 544864 bytes, checksum: 9e132bf130badf4c90a40a1d5fbc0aee (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Nessa pesquisa utilizou-se de três unidades fotoativardoras na polimerização de uma marca comercial de cimento resinoso de dupla ativação, com a interposição de uma lâmina de cerômero e de porcelana, para avaliar a microdureza superficial do cimento resinoso, considerando sua superfície do topo e da base Os corpos-de-prova foram confeccionados utilizando-se matrizes metálicas com 2mm de espessura e 16mm de diâmetro, com o orifício central medindo 8mm de diâmetro (figura 4), coincidindo com o diâmetro da ponta dos aparelhos de luz. Como espaçadores foram utilizados anéis metálicos com 2mm e 4mm de altura confeccionados de cerâmica e cerômero, na tentativa de se reproduzir as espessuras médias das restaurações indiretas realizadas clinicamente. Foram realizados quatro corpos-de-prova para cada grupo, com os três aparelhos fotoativadores e para cada grupo do material intermediário. A inserção da resina no orifício central da matriz foi realizada em uma única porção, utilizando-se de uma seringa Centrix. Após a inserção do cimento, obteve-se um pequeno excesso do material. Sobre o cimento a foi colocada uma tira de poliéster e posicionado peso de um quilo para a homogeneização e planificação da superfície. Após a remoção do peso, foi executada a ativação do cimento resinoso com a ponta dos aparelhos de luz utilizados no experimento, posicionado diretamente sobre as pastilhas de cerâmica e cerômero. Os corpos-de-prova foram removidos da matriz metálica, acondicionados em recipientes à prova de luz e mantidos a temperatura de 37o C durante 24 horas. As superfícies do topo e da base do corpo-de-prova foram polidas com lixas d'água em graus descendentes (800, 320 e 600 norton) de abrasividade e submetidas ao teste de microdureza. Para a determinação da microdureza, foi utilizado o aparelho Microdurômetro Digital MHT-110 MICROHARDNESS TESTER, Anton... . / The aim of this study was to evaluated the efficiency of three different units of light curing in activating a commercial trend of resin cement. The body-of-test had been confectioned using first metallic with 2mm of thickness and 16mm of diameter, with the central orifice measuring 8mm of diameter (figure 4), coinciding with the diameter of the tip of the light devices. As spacers metallic rings with 2mm and 4mm of height confectioned of ceramics had been used and cerômero, in the attempt of if clinically reproducing the average thicknesses of the carried through indirect restorations. They had been carried through four body-of-test for each group, with the three devices photo curing and for each group of the intermediate material. The insertion of the resin in the central orifice of the matrix was carried through in an only portion, using itself of a Centrix syringe. After the insertion of the cement, got a small excess of the material. On the cement a polyester strap was placed it and located weight of one kilo for the homogenization and planning of the surface. After the removal of the weight, was executed the activation of the resin cement with the tip of the devices of light used in the experiment, located directly on the tablets of ceramics and ceromer. The test bodies had been gotten thus the body-of-test had been removed of the metallic matrix, conditioned in containers to the test of light and kept the temperature of 37o C during 24 hours. The surfaces of the top and the base of the body-of-test had been polishing with sandpapers in degrees descending (800, 320 and 600 norton) of abrasiveness and submitted to the micro hardness test. For the determination of the micro hardness, the device Digital Micro hardness tester MHT-110 MICROHARDNESS TESTER, Anton Paar-Paar Physica, Graz was used, Austria, of the Institute of Chemistry of Araraquara (UNESP) with load of 50N during 30 seconds... (Complete abstract, click electronic address below)

Made available in DSpace on 2014-06-11T19:32:20Z (GMT). No. of bitstreams: 0 Previous issue date: 2005-04-27Bitstream added on 2014-06-13T19:06:31Z : No. of bitstreams: 1 bernardes_es_dr_rcla.pdf: 1067716 bytes, checksum: eefeb5fec6ee0538ca62fc18647588e5 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / A Formação Corumbataí (Permiano) foi estudada em suas variações verticais, em duas frentes de lavra nas proximidades de Rio Claro, enfocando as relações entre os componentes mineralógicos e as propriedades cerâmicas. A análise petrográfica das amostras coletadas nessas minas, por meio de microscópio óptico, juntamente com Microscopia Eletrônica de Varredura (MEV) dos minerais do cimento e Difração de Raios-X (DRX) com a fração argila, revelou uma assembléia mineralógica complexa com quartzo e feldspato na dimensão silte, matriz constituída por illita, esmectita-clorita, chamosita, berthierina e argilominerais interestratificados, e hematita, calcita e albita como cimento dessas rochas. Os sedimentos originais, pelíticos e ricos em ferro, foram modificados pelos eventos diagenéticos, durante a interação com soluções conatas alcalinas; processos de substituição e autigênese sucederam a diagênese inicial promovendo a formação de diferentes tipos de cimento e o crescimento dos cristais de illita. Os filossilicatos hidratados e amorfos de sílica precipitados na interface sedimento-água deram origem a esses minerais através de transformações associadas à perda de água interplanar e trocas catiônicas com os fluidos hipersalinos iniciais, mas também há evidências de forte influência de eventos magmáticos que teriam desencadeado novas transformações diagenéticas. A diagênese tardia sob influência de processos superficiais sob ação de águas meteóricas também está registrada em algumas feições, embora mais restrita pela característica impermeável dos litotipos. Os principais horizontes estratigráficos foram descritos em termos de litotipo, textura, conteúdo em argila e minerais do cimento. Análise de Componentes Principais e de Agrupamento reforça a correlação entre as feições texturais (granulometria e maturidade) e as propriedades físicas do material. / The Late Permian Corumbataí Formation was studied in its vertical variability within a couple of mine works close to Rio Claro, focusing relationships between mineralogical components and ceramics properties. The petrographic analysis of the samples collected in these mines, made by optical microscopic, Scanning Eletron Microscopy (SEM) of the cement minerals and X-ray techniques with clay fraction, revealed a complex mineralogical assemblage with quartz and feldspar in silt size grains, within a matrix constituted by illite, smectite-chlorite, chamosite, berthierine and interestratified clay-minerals, with cement of hematite, calcite and albite. The original fine-grained iron-rich sediment was modified by diagenetic events, during the interaction with alcalline conate solutions; mineralogical substitution and authigenesis followed this early diagenesis with the formation of different types of cement. The hidrous phyllosilicates and the amorphous silica precipited in the water-sediment interface played an important role on these transformations, but there are evidences of strong influence of magmatic events wich promoted another diagenetic phase generation. The principal stratigraphic horizons were described in terms of lithology, texture, argillaceous content and cement minerals. Principal Components and Clusters Analysis strains the correlation between textural features (grain size and maturity) and physical properties of the material.

A engenharia rodoviária emprega pistas-teste para avaliação de materiais, do dimensionamento estrutural e de métodos executivos de pavimentos, de modo a submeter a estrutura de pavimentos a condições reais de clima e de tráfego. Há no mundo numerosos programas de monitoramento de pistas-teste que vêm contribuindo significativamente para o avanço da tecnologia dos pavimentos. Neste contexto, o presente trabalho se propõe a avaliar o desempenho de quatro segmentos asfálticos sequenciais de um trecho experimental executado na Rodovia Fernão Dias (BR-381), que liga as cidades de São Paulo a Belo Horizonte, sob concessão pela empresa ARTERIS, sujeita a tráfego muito pesado. As estruturas de pavimentos construídas para este estudo são: pavimento flexível executado com base de Brita Graduada Simples (BGS), pavimento semirrígido executado com base de Brita Graduada Tratada com Cimento (BGTC), pavimento com base asfáltica constituída de material fresado (RAP) estabilizado com emulsão asfáltica e pavimento com base asfáltica constituída de material fresado (RAP) estabilizado com espuma de asfalto. A avaliação do desempenho foi realizada a partir de análises dos resultados de monitoramentos funcionais e estruturais realizados em campo periodicamente até a idade de 15 meses. Em laboratório, realizou-se a caracterização dos materiais empregados na construção utilizando o módulo de resiliência como parâmetro para avaliar a rigidez dos mesmos. A partir de análises funcionais, procedeu-se à avaliação da progressão de defeitos, dentre eles a irregularidade longitudinal, afundamentos em trilha de roda e características de superfície. Como foco principal, foram analisados o comportamento mecânico de cada segmento. As bacias de deslocamentos foram avaliadas por meio de indicadores estruturais e utilizadas para realização de retroanálises com o objetivo de estudar a variação destes indicadores e dos módulos das camadas, a depender do volume de tráfego acumulado e condições climáticas. Estes dados foram também empregados para relacionar as estruturas com os defeitos de superfície, além de alimentar um modelo computacional em elementos finitos que descreve o comportamento mecânico dessas estruturas. Os resultados obtidos nos monitoramentos periódicos e nas análises realizadas mostraram que o pavimento flexível não é adequado ao tráfego muito pesado e a partir dos 12 meses não atendia os limites da ANTT para rodovias sob concessão federal, enquanto o pavimento semirrígido mostrou-se adequado e estável ao longo do período estudado e os pavimentos reciclados apresentaram um ganho nos parâmetros estudados, devido ao processo de cura dos materiais utilizados, além de comportamento adequado ao tráfego submetido. / The highway engineering adopts road tests to evaluate pavement materials, structural design methods and pavement construction characteristics, with the goal of subjecting the pavement structure to real climate and traffic conditions. There are several road test monitoring programs worldwide, which significantly contribute to pavement technology development. The present study evaluates the performance of four pavement sections within a road test located in Rodovia Fernão Dias (BR-381), that connects São Paulo and Belo Horizonte cities under concession of Arteris, and is subjected to heavy traffic. The pavement structures built can be described as follows: flexible pavement with crushed stone base layer, semirigid pavement with cement-treated crushed stone base layer, pavement with base layer of RAP stabilized with emulsion asphalt and pavement with base layer of RAP stabilized with foamed asphalt. The pavement performance was evaluated by means of a functional and structural periodic field monitoring during 15 months. In laboratory, the materials stiffness was characterized from resilient modulus tests. The functional analysis was conducted to study the progression of pavement distresses, such as roughness, rutting and surface characteristics. Furthermore, as the main focus structural aspects were analyzed. Deflection basins were evaluated from its parameters and used for backcalculated moduli analysis, with the objective of comprehend the susceptibility of these parameters and layers moduli to climate and traffic conditions. These results were used to compare the structures with surface distresses, and were also used as input of a computational finite element model to describe the mechanical behavior of these structures. The results obtained from the periodic monitoring and analysis showed that the flexible pavement is not suitable for very heavy traffic and from the 12 months it did not meet the ANTT limits required for highways under federal concession, while the semi-rigid pavement proved to be adequate and stable during the studied period and the recycled pavements with presented an improvement in the studied parameters, due to the curing process of the materials used, and also presented adequate behavior to the submitted traffic.

Orientador: Mário Tanomaru Filho / Resumo: Materiais reparadores e cimentos endodônticos não devem promover alteração da coloração dental. Este estudo foi dividido em 3 publicações. Publicação 1 - avaliação da alteração cromática dentária promovida por cimentos de silicato tricálcico (TSC) associado com óxido de bismuto (TC-Bi), óxido de zircônio (TC-Zr), óxido de nióbio (TC-Nb) e Biodentine (BD). Publicação 2 - comparação dos efeitos cromáticos induzidos por cimentos TSC-Bi e silicato tricálcio com tungstato de cálcio (TSC-TC), MTA Angelus (MTA) e MTA HP Repair (MTAHP). Publicação 3 - avaliação das alterações cromáticas por cimentos endodônticos, AH Plus (AHP), MTA Fillapex (MTAF), Total Fill BC Sealer (TF) e NeoMTA Plus (NMTAP). Dentes bovinos (n=10) foram seccionados para obtenção de secções vestibulares e palatinos. Na face interna vestibular foram realizadas duas cavidades, uma na porção coronária e outra radicular, que foram preenchidas pelos materiais em estudo e com pasta triantibiótica como controle positivo (CP) e cavidades sem material como controle negativo (CN). A mensuração da alteração cromática (∆E) e luminosidade (L*) foram realizadas com espectrofotômetro, antes da inserção dos materiais (T0), imediatamente após a inserção (T1) e após 7 (T7), 15 (T15), 30 (T30), 60 (T60), 120 (T120) e 180 (T180) dias. Os dados foram avaliados por meio de teste de Análise de Variância de medidas repetidas a dois critérios e Post Hoc teste LSD-Fisher, ambos com nível de significância de 5%. Publicação 1 - na porção cor... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Repair materials and endodontic sealers should not promote tooth staining. This study was divided into 3 publications. Publication 1 - evaluation of dental discoloration of tricalcium silicate (TSC) cements associated with bismuth oxide (TC-Bi), zirconium oxide (TC-Zr), niobium oxide (TC-Nb) and Biodentine (BD). Publication 2 - comparison of the color effects induced by TSC-Bi cements and tricalcium silicate with calcium tungstate (TSC-TC), MTA Angelus (MTA) and MTA HP Repair (MTAHP). Publication 3 - evaluation of color changes by endodontic cements, AH Plus (AHP), MTA Fillapex (MTAF), Total Fill BC Sealer (TF) and NeoMTA Plus (NMTAP). Bovine teeth were sectioned to obtain vestibular and palatine sections. In the internal vestibular face, two cavities were performed, one in the coronary portion and the other one in the root, which were filled with the materials, and triantibiotic paste as the positive control (CP) and cavities with no filling as the negative control (CN). The measurement of the color change (ΔE) was performed with a spectrophotometer, before insertion of the materials (T0), immediately after insertion (T1) and after 7 (T7), 15 (T15), 30 (T30), 60 (T60), 120 (T120) and 180 (T180) days. The data were evaluated by Variance Analysis of repeated measurements at two criteria and Post Hoc LSD-Fisher test, both with a significance level of 5%. Publication 1 - in the coronary portion TSC and CP presented higher ΔE in T180 compared to T1 (p <0,05). Only TSC-Zr and TSC-... (Complete abstract click electronic access below) / Mestre

Made available in DSpace on 2014-10-09T12:43:04Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:05:35Z (GMT). No. of bitstreams: 1 06124.pdf: 4912252 bytes, checksum: a10b5a0b5037f2df963acd926b7b2c97 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP