FBC-ashes, as a waste product of a relatively new technology of combustion, so-called fluidized bed combustion, cannot be used for building materials production in contrast to fly-ashes. Problem rests in their chemical as well as their mineralogical composition. Thought it can be admitted that FBC-ash may be used for preparation of the hydraulic binder with a similar chemical and mineralogical composition, but only in a certain limit of concentration. The first part of this thesis was focused on the potentialities of fluid fly ashes utilization as hydraulic bonding material in preparation of dry mortar mixtures and the second part of works was engaged in research development of burned hydraulic binder of FBC ash. The thesis explores the conjunction between parameters of burning mode and hydraulic binder characteristics.

The primary objective of this study is to evaluate the clogging potential of installed pervious concrete systems, to analyze rehabilitation techniques and develop construction specifications for the construction of portland cement pervious concrete specific to the state of Florida. Currently, a consistent statewide policy has not been established in reference to credit for storage volume within the voids in pervious concrete and the coarse aggregate base. For this reason a current and updated assessment of pervious pavement is needed to benefit from the advantages of pervious pavement use in low traffic volume areas. Initially by modeling a pervious concrete system in a field laboratory with test cells of typical Florida soil conditions and groundwater elevations and combining these data with field data from multiple sites of long service life, a Florida specific construction methodology has been developed. It is hoped that by developing a more standardized design criteria for pervious pavements in Florida a statewide acceptance of portland cement pervious pavement can be achieved and credit can be earned based on the volume of stored stormwater. This study of field sites was subsequently expanded to include locations in the southeastern United States. Pervious concrete has suffered historically poor support due to a number of factors, including concern about poor long term performance due to clogging of surface pores. Eight existing parking lots were evaluated to determine the infiltration rates of pervious concrete systems that have had relatively no maintenance. Infiltration rates were measured using an embedded single-ring infiltrometer developed specifically for testing pervious concrete in an in-situ state. The average infiltration rates of the pervious concrete that was properly constructed at the investigated sites ranged from 0.4 to 227.2 inches per hour. A total of 30 pervious concrete cores were extracted and evaluated for infiltration rates after various rehabilitation techniques, including pressure washing, vacuum sweeping and a combination of the two methods, have been performed to rehabilitate the infiltration capability of the concrete. By evaluating the effectiveness of these rehabilitation techniques, recommendations have been developed for a maintenance schedule for pervious concrete installations. In most cases it was found that the three methods of maintenance investigated in this study typically resulted in a 200% or greater increase over the original infiltration rates of the pervious concrete cores. It is therefore recommended that as a general rule of thumb one or a combination of these rejuvenation techniques should be performed when the system infiltration rates are below 1.5 inches per hour to maintain the infiltration capability of pervious concrete pavements.

No / The setting of Roman cement is so rapid as to make the use of retardation essential in most practical mortars. This work reports an approach to retardation of Roman cement mortars by means of a pre-hydration process in which pre-determined amounts of water (de-activation water) are added to the cement prior to subsequent mortar formation. It is shown that this process yields both monocarboaluminate and a carbonated AF(m) phase, the balance of which is modified by storage time; the belite phases are not affected. Increases in both de-activation water and pre-hydrated mix storage time yield a longer workable life and slightly lower strength of the mortar. An increase in de-activation water also yields an increase in shrinkage whilst an increase in storage time results in a reduction in shrinkage. Other parameters such as mixing protocol and re-mixing affect workable life without compromising the strength. (C) 2013 Elsevier Ltd. All rights reserved.

Asphalt-Portland Cement Concrete Composite (APCCC) is a hot-mix asphalt with air voids in the range of 25 to 30 percent which is later filled with resin modified cement grout. The resin modified cement grout consists of portland cement, fly ash, sand, water, and prosalvia (PL7) additive. The objective of the research was primarily to evaluate the asphalt-portland cement concrete composite under laboratory conditions. Asphalt-portland cement concrete composite specimens were prepared using the Marshall procedure. The physical and durability properties of APCCC were evaluated at one, three, seven, and 28 days of curing. The evaluated physical properties include stability, indirect tensile strength, compressive strength, and resilient modulus, while the evaluated durability properties include water sensitivity, freeze-thaw and chloride intrusion resistance. Specimens were also tested for different moist curing levels to evaluate the optimum moist curing period. Three moist curing periods were evaluated: no-moist curing, one-day moist curing, and three-day moist curing. The test results were compared with those of SM-5 hot-mix asphalt (a Virginia surface mix); results of chloride intrusion resistance were compared with those of portland cement concrete specimens exposed to similar conditions. The study concluded that asphalt-portland cement concrete composite is an effective alternative technique to be used as an overlay on bridge decks especially with preformed membranes, due to its high strength, durability, and lower air void content. / Master of Science

Portland cement concrete (PCC) structures deteriorate with age and need to be maintained or replaced. Early detection of deterioration in PCC (e.g., alkali-silica reaction, freeze/thaw damage, or chloride presence) can lead to significant reductions in maintenance costs. However, it is often too late to perform low-cost preventative maintenance by the time deterioration becomes evident. Non-destructive evaluation (NDE) methods are potentially among the most useful techniques developed for assessing constructed facilities. They are noninvasive and can be performed rapidly. Portland cement concrete can be nondestructively evaluated by electrically characterizing its complex dielectric constant. The real part of the dielectric constant depicts the velocity of electromagnetic waves in PCC. The imaginary part describes the conductivity of PCC and the attenuation of electromagnetic waves, and hence the losses within the PCC media. Dielectric properties of PCC have been investigated in a laboratory setting using a parallel plate capacitor operating in the frequency range of 0.1MHz to about 40MHz. This capacitor set-up consists of two horizontal-parallel plates with an adjustable separation for insertion of a dielectric specimen (PCC). While useful in research, this approach is not practical for field implementation In this research, a capacitance probe has been developed for field application. The probe consists of two planar conducting plates and is made of flexible materials for placement on exposed surfaces of the specimens to be tested. The calibration method of both capacitive systems has been extensively studied to minimize systematic errors in the measurement process. These two measurement systems will be discussed and compared to one another on the basis of sensitivity and measurement repeatability. / Master of Science

Submitted by Kamila Costa (kamilavasconceloscosta@gmail.com) on 2015-07-03T19:40:13Z No. of bitstreams: 2 Dissertação-José C Feitoza.pdf: 2651343 bytes, checksum: 7a35d74605d8cb0399047e68bf28ebaf (MD5) ficha_catalográfica.pdf: 1964 bytes, checksum: 433c944e93f4431471bf2eccf730679e (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2015-07-13T15:06:21Z (GMT) No. of bitstreams: 2 Dissertação-José C Feitoza.pdf: 2651343 bytes, checksum: 7a35d74605d8cb0399047e68bf28ebaf (MD5) ficha_catalográfica.pdf: 1964 bytes, checksum: 433c944e93f4431471bf2eccf730679e (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2015-07-13T15:17:35Z (GMT) No. of bitstreams: 2 Dissertação-José C Feitoza.pdf: 2651343 bytes, checksum: 7a35d74605d8cb0399047e68bf28ebaf (MD5) ficha_catalográfica.pdf: 1964 bytes, checksum: 433c944e93f4431471bf2eccf730679e (MD5) / Made available in DSpace on 2015-07-13T15:17:35Z (GMT). No. of bitstreams: 2 Dissertação-José C Feitoza.pdf: 2651343 bytes, checksum: 7a35d74605d8cb0399047e68bf28ebaf (MD5) ficha_catalográfica.pdf: 1964 bytes, checksum: 433c944e93f4431471bf2eccf730679e (MD5) Previous issue date: 2015-04-29 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This study evaluated two cold flexible pavement recycling techniques "in situ" with the addition of Portland cement (CP II E 32) for the base layer, through analysis of the laboratory tests results and reviews of experimental sections performed on Highway Visconde Porto Seguro / SP, called SP 332, in the granting of DER-SP. Laboratory tests were conducted to prove the influence of the variability of the aggregates and the effect of Portland cement content in the dosage of recycled cold mixtures using mechanical behavior results as evaluation criteria in order to certify the technical quality of recycling layer base. The design of the passages in the experimental track allowed the determination of the flexible pavement recycling methods in situ with the mobile plant KMA 200 and the Wirtgen 2500S equipment for recycling. The monitoring the implementation, by companies, helped to understand the advantages and limitations the set of equipment employed in both recycling techniques of the experimental lane. The monitoring of experimental sections, during and after the construction process, allowed to verify that the cold recycling solution of flexible pavement for technical study, is beneficial to the structural and functional condition thereof. / Esta pesquisa avaliou duas técnicas de reciclagem a frio de pavimentos flexíveis in situ com adição de cimento Portland (CP II E 32) para camada de base, por meio de análises dos resultados de ensaios laboratoriais e avaliações de trechos experimentais executados na Rodovia Visconde de Porto Seguro/SP, denominada de SP 332, sob a concessão do DER-SP. Os ensaios laboratoriais foram conduzidos a fim de comprovar a influência da variabilidade dos agregados e o efeito do teor de cimento Portland na dosagem de misturas recicladas a frio, utilizando resultados de comportamento mecânico como parâmetros de avaliação para atestar a qualidade técnica da reciclagem da camada de base. A concepção dos trechos na pista experimental permitiu determinar os métodos de reciclagem do pavimento flexível in situ com a usina móvel KMA 200 e com a recicladora Wirtgen 2500 S. O acompanhamento da execução, pelas empresas fomentadoras, contribuiu para compreender as vantagens e limitações do conjunto de equipamentos empregados nas duas técnicas de reciclagem da pista experimental. O monitoramento dos trechos experimentais, durante o processo construtivo e posterior a execução, permitiu verificar que a solução de reciclagem a frio do pavimento flexível para as técnicas em estudo, é benéfica para a condição estrutural e funcional dos mesmos.

One of the most prominent measurable parameters of the development of phases and phase transformations in inorganic systems are undoubtedly the volume changes of silicate matrix. The study of volume changes is crucial in the terms of usable durability of final product. They represent shrinkage or expansion of the material and may lead to significant decrease of technological and ecological parameters and often to complete destruction of these materials. Most often the volume changes can be observed when cement is used as a binder and in concretes, mortars, artificial aggregates and other similar materials. There are many methods to detect, define and determine the volume changes qualitatively or quantitatively. The development of phases was investigated as a part of the dissertation thesis and hence the volume changes were observed under the conditions closest to the real state in the construction industry. The raw materials and admixtures were selected which model the content of hazardous components present in conventional materials (both natural and secondary), used in construction and the relationship with volume changes was searched and demonstrated. The contacts for measuring the volume changes were attached to test surfaces of specimens and the physical - mechanical tests (volume changes, phase changes, strength, etc.), chemical analysis and ecotoxicity tests depending on the length of hydration were performed.

Baigiamojo magistro darbo tikslas – ištirti cheminių įmaišų poveikį reologinėms portlandcemenčio tešlos savybėms, panaudojant skirtingų tipų cementus. Darbe išnagrinėta lietuvių, užsienio mokslinė literatūra, aprašytos naudotos žaliavos, parinktos skirtingos cementinės tešlos sudėtys, kurios skiriasi cemento ir plastifikuojančios įmaišos tipu. Tyrimams naudotos šios medžiagos: AB „Akmenės cementas“ gamyklos portlandcementis CEM I 42,5 (N ir R ankstyvojo stiprumo), klinties portlandcementis CEM II/A-LL 42,5 N, plastiklis Centrament N3, naujausios kartos superplastiklis MC-PowerFlow 3140 ir vanduo. Ištirtas plastiklio ir superplastiklio poveikis portlandcemenčio tešlos vandens ir cemento (V/C) santykio pokyčiams ir sklidumui naudojant Sutardo viskozimetrą. Buvo tiriamos vienodo vandens ir cemento santykio portlandcemenčio tešlos su cheminėmis įmaišomis ir be jų. Tyrimai atlikti naudojant rotacinį viskozimetrą Rheotest NH 4.1 su bendraašiais cilindrais. Nustatytas cheminių įmaišų portlandcemenčio tešloje veiksmingumas, esant skirtingo tipo cementui. Pastebėta, kad portlandcemenčio tešlos dinaminis klampis gali būti reguliuojamas cheminėmis įmaišomis viso indukcinio hidratacijos periodo metu. Sukurta metodika portlandcemenčio tešlos reologinėms savybėms nustatyti bei parinktas reologinis modelis, kuris geriausiai apibūdina gautus tyrimų duomenis. Atlikus portlandcemenčio tešlos su cheminėmis įmaišomis ir be jų tyrimų rezultatų regresinę analizę, gautos klampio, tekėjimo lygtys... [toliau žr. visą tekstą] / The purpose of this thesis is to analyse the influence of chemical admixtures on the rheological properties of Portland cement paste, which differ depending on the type of cement used. In addition to the literature analysis, different cement paste compositions (differing in type of cement and plasticizers) were tested. Testing materials: Portland cement CEM I 42.5 (N and R early strength), limestone Portland cement CEM II/A-LL 42.5 N, plasticizer Centrament N3, the latest generation superplasticizer MC-PowerFlow 3140 and water. Research focused on effects of plasticizer and superplasticizer on water and cement (W/C) ratio and Portland cement paste slump-flow characteristics. Portland cement pastes with the same water-cement ratio with and without chemical admixtures were tested. Tests were carried out using a Suttard viscometer and rotation viscometer Rheotest NH 4.1 with coaxial cylinders. It was observed that viscosity of Portland cement paste can be controlled by chemical admixtures during the hydration induction period. The work provides analysis of the effectiveness of the chemical admixtures on the rheological properties of the Portland cement pastes, comparing it with a control composition of the Portland cement paste. Diagrams demonstrate changes in viscosity of the Portland cement pastes depending on the type and amount of the chemical admixtures. Obtained results were compared with the same consistence paste without admixtures. We created a new methodology of... [to full text]

O presente trabalho consiste na detalhada caracterização geológica da Mina de Vallemí no Paraguai, utilizada para fabricação de cimento Portland pela Industria Nacional de Cemento (INC), seguida da caracterização das matérias-primas, por petrografia e análises químicas e mineralógicas, e posteriores testes de queimabilidade de seis farinhas experimentais, elaboradas com misturas das matérias-primas disponíveis. As farinhas foram sinterizadas e avaliadas qualitativamente, por microscopia do clínquer, e quantificadas por difração de raios-X (DRX) e método de Rietveld. A geologia da mina consiste em metapelitos, por vezes em alternâncias rítmicas, com metacalcários (metaritmito) da Formação Vallemí, basal, sobrepostos por metacalcários puros, com intercalações de metadolomito, da Formação Camba Jhopo, ambas do Grupo Itapucumí (Ediacarano), dispostas em dobra isoclinal com flanco invertido (Faixa de Dobramentos Vallemí). Dada à diversidade litológica e complexidade tectônica, o estudo requereu mapeamento geológico detalhado (escala 1:2000), com coleta de amostras e análise química concomitante, no laboratório de qualidade da indústria, e atualização da topografia e modelagem 3D. Foram individualizados nove litotipos: 1) Litotipo Misto (Itá jopara); 2) Litotipo Ritmito Verde (Itá hovy?); 3) Litotipo Ritmito Vermelho (Itá pytã); 4) Litotipo Calcário Cinza (Itá hungy); 5) Litotipo Calcrete (Itá manduvi sa\'yju); 6) Litotipo Dolomito (Itá pytãngy); 7) Litotipo Arenito Vermelho (Itá atã pytã); 8) Litotipo Lamprofiro (Itá h?); 9) Litotipo Vulcânica Básica (Itá kui sa\'yju), sendo os cincos primeiros apropriados para fabricação de cimento. O Litotipo Dolomito é apropriado se usado em misturas e os demais são materiais estéreis. Foram realizadas seis diferentes misturas de litotipos, além da normalmente empregada na indústria, utilizada como referência, com avaliação do índice de queimabilidade (IQ) nos laboratórios da Associação Brasileira de Cimento Portland (ABCP). As farinhas D1, D3 e D4 foram classificados como fácil de queimar, e as demais, D2, D5b e D6b, com queimabilidade normal. Pode-se dizer que todas apresentam índices de queimabilidade compatíveis com os padrões exigidos para a produção de cimento Portland, destacando que a melhor mistura foi obtida com a farinha D4 (composta por Litotipo Ritmito Vermelho 83,07%, Litotipo Ritmito Verde 14,45% e mineral de ferro 1,48%), e a de menor desempenho a D5b (composta por Litotipo Calcrete 50,17%, Litotipo Misto 48,32% e mineral de ferro 1,52%), o que foi possível também corroborar na quantificação das fases do clínquer. / The present work deals with a detailed geological characterization of the Vallemí Mine in Paraguay, explored to manufacture of Portland cement by the National Cement Industry (INC), followed by the characterization of the raw materials, by petrography, chemical and mineralogical analyzes, and subsequent burnability tests of six experimental raw mixtures, prepared with mixtures of available raw materials. The flours were sintered and evaluated qualitatively by clinker microscopy and quantified by X-ray diffraction (XRD) and Rietveld method. The geology of the mine includes metapelites, sometimes in rhythmic alternations, with metalimestone of the Vallemí Formation, basal, overlapped by pure metalimestone, with intercalation of metadolomite, of the Camba Jhopo Formation, both of the Itapucumí Group (Ediacaran), arranged in fold isoclinal with inverted flank (Vallemí Folding Belt). Due to the lithological diversity and tectonic complexity, the study required detailed geological mapping (scale 1: 2000), with sample collection and concomitant chemical analysis, in the industrial quality laboratory, and updating the topography and 3D modeling. Nine lithotypes were individualized: 1) Litotipo Misto (Itá jopara); 2) Litotipo Ritmito Verde (Itá hovy?); 3) Litotipo Ritmito Vermelho (Itá pytã); 4) Litotipo Calcário Cinza (Itá hungy); 5) Litotipo Calcrete (Itá manduvi sa\'yju); 6) Litotipo Dolomito (Itá pytãngy); 7) Litotipo Arenito Vermelho (Itá atã pytã); 8) Litotipo Lamprofiro (Itá h?); 9) Litotipo Vulcânica Básica (Itá kui sa\'yju), the first five suitable for manufacturing cement. Litotipo Dolomito is applicable if used in mixtures. The others lithotype are sterile materials. Six different mixtures of lithotypes were carried out, besides the one normally used in industry, used as reference, with evaluation of the burnability index (IQ) in the laboratories of the Assocciação Brasileira de Cimento Portland (ABCP). Flours D1, D3 and D4 were classified as easy to burn, and the others, D2, D5b and D6b, with normal burning. It is possible to say that all of them have a comparable burnability index compatible with the standards required for Portland cement production, the best mixture was obtained with the raw mixture D4 (composed by Litotipo Ritmito Vermelho 83,07%, Litotipo Ritmito Verde 14,45% and iron ore 1,48%) and the D5b (composed by Litotipo Calcrete 50,17%, Litotipo Misto 48,32% and iron ore 1,52%) appear as the worst, which were corroborated in the quantification of clinker phases.

O progresso científico e tecnológico das últimas décadas registra um avanço significativo no processo de obtenção da cal, porém, há uma lacuna de conhecimento de base referente à sua ação quando empregada em conjunto com o cimento Portland. O uso da cal nas argamassas mistas de acabamento tem sido associado positivamente apenas à plasticidade no estado fresco e à sua deformabilidade no estado endurecido. Maiores informações são necessárias sobre a ação da cal na evolução das propriedades da argamassa no estado fresco, vinculadas à hidratação do cimento. Este conhecimento é importante para o desenvolvimento de formulações que atendam ao desempenho desejado em diferentes aplicações. O entendimento do mecanismo de hidratação do cimento em presença da cal constitui uma plataforma para estudos de adições minerais ativas ao clínquer, com adição de cal hidratada como fonte externa de cálcio, na produção de novos materiais cimentícios sustentáveis. O estudo em pasta realizado teve como foco a interação cimento-cal visando identificar os fenômenos químicos e físicos relevantes que se sucedem à adição de água ao sistema. Foram caracterizadas as idades iniciais de hidratação do cimento por meio de ensaios de calorimetria de condução, termogravimetria (TG/DTG) e difratometria de raios X em material no estado fluido e em regime consecutivo de coleta de dados. Os experimentos envolveram as proporções 1:1 e 1:2 de cimento Portland tipo CP II E com cales hidratadas tipos CH I e CH III de natureza cálcica e dolomítica, respectivamente. A cal CH I incorpora à mistura elevado teor de hidróxido de cálcio com imediata saturação do meio por íons hidroxila e íons cálcio; a cal CH III incorpora também, em maior quantidade, filler carbonático. Por efeito químico, devido à presença da cal, há alteração da velocidade de hidratação, mas com formação dos produtos de reação característicos da hidratação do cimento. Por efeito físico, o filler carbonático e a fração insolúvel do hidróxido de cálcio da cal, presente no meio saturado, atuam como nucleador para precipitação de fases hidratadas. O efeito combinado desses fenômenos promoveu aceleração da hidratação do cimento Portland, principalmente no período de indução, quando prevalecem as reações de formação de etringita e de aluminatos de cálcio hidratados. / In the last decades, scientific and technological progress has shown a significant advance in the process of obtaining lime; however, there is gap knowledge with relation to its action when employed together with Portland cement. The use of lime in finishing mix mortars has only been positively associated to the fresh state plasticity and ability to deformation in the hardened state. It is necessary to collect data about the role of lime in the gradual development of the properties of mortars in the fresh state, linked to cement hydration. Such knowledge is important to develop formulas which can meet the required performance in different uses. The current demand of sustainable materials has favored the addition of minerals to the composition of Portland cement, and hydrated lime as an extern source of calcium, is a feasible alternative to the composition of byproducts and mixtures to be used as alternative binders. This research focused the cement-lime interaction aiming at identifying relevant chemical and physical phenomena which succeed the addition of water to the system. The paste study characterized the early ages of hydration by means of isothermal calorimetric, thermogravimetric, X-ray diffraction in material in the fluid state analysis collecting data in a consecutive basis. The experiments were carried out by using two proportions of Portland cement type CP II E with hydrated lime types CH I and CH III, calcic and dolomitc, respectively. By adding lime CH I to the cement-water system, calcium hydroxide is abundantly incorporated, with immediate saturation by means of hydroxide ions and calcium ions. The addition of lime CH III, also incorporates, in greater amount, finely ground limestone. Due to chemical effect because of the presence of lime, there is alteration in speed of hydration, forming products characteristics to the cement hydration process. Due to physical effect, the filler and the lime insoluble fraction of calcium hydroxide, present in the saturated environment, work as facilitators to the precipitation of the hydrated phases. The combined effect of these two phenomena accelerated hydration of Portland cement, mainly in the induction period, when ettringite and hydrated calcium aluminates formation reactions prevail. The advancement made in terms of knowledge permits to broaden comprehension on the behavior of mixtures in early stages, when hardening and consolidation processes are applied to mortars and help rheologic studies which involve their application. The understanding of the hydration mechanism in the presence of lime sets a base to study additions of active minerals to the clinker and produce new sustainable cementious compounds.