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Elgalhud, Abdurrahman Ahmed T. A. "Durability potential of Portland limestone cement concrete." Thesis, University of Birmingham, 2017. http://etheses.bham.ac.uk//id/eprint/7903/.
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There is an increasing global concern that has led to efforts to lessen the carbon footprint of the cement industry and make concrete manufacturing more sustainable by using other types of materials as supplements or alternatives, primarily for Portland cement (PC). This research work is concerned with the analytical systemisation, including the analysis, evaluation and structuring of global published experimental results, of ground limestone (GLS) used in concrete as a partial replacement of PC. The work is focussed on the physical and chemical characterisation of GLS and its effects on pore structure (in terms of porosity, water absorption and sorptivity), compressive strength and the durability of the concrete in terms of the carbonation and chloride ingress and the corrosion of steel reinforcement, including a statistical modelling of the carbonation of concrete with Portland limestone cement (PLC). Overall, it is suggested that, though the use of GLS up to 25% with PC should not impair the pore structure, the limit on GLS content for its effect on strength is likely to be about 15%. This should be considered where a higher proportion of GLS content is allowed in the standards. It is also shown that the carbonation rate and chloride ingress into concrete increase with increasing GLS content.
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Igarashi, Hasegawa Lucia. "Carbonation curing and performance of pervious concrete using Portland limestone cement." Thesis, McGill University, 2011. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=104896.
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Pervious concrete is an innovative material with several environmental advantages. Studies on the properties and performance of ordinary Portland cement (OPC) pervious concrete have been done worldwide. Portland limestone cement (PLC) has recently been introduced into the Canadian market as a greener option than OPC. This thesis explores the possibility of using PLC in pervious concrete to achieve technical and environmental benefits.Since the major application of pervious concrete is pavements, it is important to find a way to accelerate the concrete curing process, as one of the most important factors in determining the cost and impact of road work is the construction time. Pervious concrete is the ideal material to cure by carbonation in a feasible way. It is usually designed without reinforcement, so the reduction of the concrete pH value resulting from the process has no impact. Additionally, the open massive pore structure provides a larger surface to optimize CO₂ penetration during the curing process. This study focuses on the effect of carbonation on early age strength and freezing and thawing durability of PLC pervious concrete. It was found that, under the same conditions, PLC pervious concrete shows lower compressive strengths and higher absorption than the OPC counterpart. The optimization of the mixture proportion by including admixtures would permit the use of PLC to generate a pervious concrete with strengths equivalent to OPC pervious concrete. Carbonation curing of PLC pervious concrete increased early age compressive strength, and maintained a comparable final strength. In addition, carbonation curing increased resistance to absorption, but decreased the resistance to freezing and thawing cycles in saline solution. Therefore, carbonation curing of pervious concrete is not recommended for cold climates.Le béton drainant est un matériau innovant avec plusieurs avantages environnementaux. Des études portant sur les propriétés et la performance du béton drainant au ciment Portland ordinaire (CPO) ont été réalisées internationalement. Le ciment Portland au calcaire (CPC) a fait son arrivée sur le marché canadien récemment et s'avère une option plus écologique que le CPO. Cette thèse explore la possibilité d'utiliser CPC en béton drainant pour obtenir avantages techniques et environnementaux. Une des applications majeures du béton drainant est le pavage. Pour cette raison, c'est important de trouver une façon d'accélérer le processus de durcissement du béton, puisque le temps de construction est l'un des facteurs les plus importants déterminant le coût et l'impact des travaux routiers. Le béton drainant est le matériau idéal à mûrir au carbone de manière faisable. Il est fabriqué sans armature et donc, la réduction du pH du béton résultant du processus de carbonatation n'a aucun impact. De plus, la structure ouverte massive des pores offre une surface plus grande permettant d'optimiser la pénétration de CO₂ au cours du processus de mûrissement. Cette étude a pour but de déterminer l'effet de la carbonatation sur la résistance à jeune âge et la durabilité au gel/dégel du béton drainant fabriqué avec le CPC. Les résultats indiquent que, pour les mêmes conditions, il y a une réduction de la résistance à la compression et une meilleure absorption avec le béton drainant au CPC comparé avec ceux au CPO. L'optimisation du dosage par l'inclusion d'ajouts cimentaires et chimiques, permettrait l'utilisation du CPC pour générer un béton drainant avec des résistances équivalentes au béton drainant au CPO. Le mûrissement au carbone du béton drainant au CPC a augmenté la résistance à la compression à jeune âge, et a maintenu une résistance finale comparable. De plus, le mûrissement au carbone a augmenté la résistance à l'absorption, mais a réduit la résistance aux cycles de gel/dégel en solution saline. Par conséquent, le mûrissement au carbone du béton drainant n'est pas recommandé pour les climats froids.
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Hartshorn, Sarah Ann. "Sulphate attack of Portland limestone cements." Thesis, University of Sheffield, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.301594.
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Angadi, Prokshit. "Portland Limestone Cement with Fly Ash: Freeze-Thaw Durability and Microstructure Studies." Thesis, North Dakota State University, 2018. https://hdl.handle.net/10365/32057.
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In this study, the freeze-thaw performance and other engineering properties of different cementitious mixtures containing Type I/II portland cement, Type IL (10) portland Limestone cement (PLC) and Coarse Ground cement (CG-P) with or without partial replacement of fly ash (Class F) were examined. The goal was to develop a concrete mixture with better or similar freeze-thaw durability without adversely affecting other engineering properties of concrete.
Crucial engineering properties reviewed include compressive strength, splitting tensile strength, workability, the degree of hydration, setting time, shrinkage and resistivity. The study was divided into two parts, one consisting of mechanical testing of engineering properties including the freeze-thaw test. The second part consisted of microstructure study which involved detection and quantification of micro-cracks/defects using μ-CT and fluorescence microscopy. The results showed that the portland limestone cement in combination with fly ash demonstrated better or similar durability in comparison to the conventional portland cement concrete mixtures.
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Aguero, Sixto Humberto. "Process analysis and energy efficiency improvement on Portland limestone cement grinding circuit." Thesis, University of British Columbia, 2015. http://hdl.handle.net/2429/52867.
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Worldwide cement production is a high energy consuming industry; 90% is thermal and 10% is electrical energy. This is the third most anthropogenic related carbon dioxide emitting industry in the world. With a rising price of energy and a growing emphasis on environmental issues the cement industry is facing significant challenges to both remain a competitive and sustainable. Composite cement manufacturing is one alternative that is used reduce energy use and greenhouse gas emissions. The dry grinding process used for finished product represents 40-50% of electrical energy consumption. It is a very inefficient process generally ranging around 1% efficient.
This research evaluated the process of a typical Portland cement grinding circuit in order to identify inefficiencies in the process and how the operating parameters may be changed in order to improve the system’s performance. Tests were conducted using samples from a B.C. cement producer and results analyzed in order to characterize and build a high accuracy model that can be used as a bench marking tool. Representative sampling and mass balance were performed on the circuit using real steady state operative conditions data provided by process plant managers.
Major research findings are:
• Air separator efficiency is rated 46.06% efficiency at fractions below 35 microns.
• High dust load feed and agglomeration are the main reasons for this low separator efficiency.
• Agglomeration effect is related to overgrinding, high energy impacts and the use of limestone.
• Whiten model is an adequate tool to fit and correct experimental data on cement air separators and to provide quantification of operating factors to evaluate the separation process.
• Low grinding kinetics at ball mill compartment 01, suggests improper size grinding media selection and high wear rate for the case studied (for media and liners).Applied Science, Faculty of
Mining Engineering, Keevil Institute of
Graduate
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Elmakki, Rihab Abdelrahman Mohamed. "The effect of extending four cements with limestone with addition of super-plasticisers on the hydration reaction of SCC cement paste." Thesis, Cape Peninsula University of Technology, 2016. http://hdl.handle.net/20.500.11838/2466.
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Thesis (MTech (Civil Engineering))--Cape Peninsula University of Technology, 2016.The addition of certain fillers and additives in conventional concrete is imperative for improving its rheological properties. The effect of additives, namely limestone (LS) and superplasticisers (SP), on the hydration kinetics of self-compacting concrete (SCC) was investigated on cement paste scale. These additives interact mostly with cement paste, since aggregates are considered to be inert materials. An understanding of the effect of these additives on the hydration kinetics of cement paste is paramount to the design of an SCC with excellent properties. Four CEM I 52.5N Portland cements from one supplier but produced at different factories, LS and two types of SP, were used in this research. The hydration kinetics were evaluated by monitoring the elastic modulus growth of the cement pastes. Different coefficients of the self-acceleration kinetics equation – the self-acceleration constant, characteristic time and real time of hydration – were used to establish the effect of different concentrations of SP with and without the optimum concentration of limestone (30%) on the hydration kinetics of cement pastes. As far as can be ascertained, this is the first time the rheokinetic model has been used to describe the initial hydration of SCC paste.
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Soyluoglu, Serdar. "Effects Of Separate And Intergrinding On Some Properties Of Portland Composite Cements." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/3/12611365/index.pdf.
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In the production of cement, to increase the cement/clinker ratio and decrease CO2 emission, the most important alternative is to produce mineral admixture incorporated cements (CEM II-III-IV-V) instead of portland cement
(CEM I). These cements are usually produced by intergrinding the portland cement clinker and the mineral admixtures. However, the difference between grindabilities of the different components of such cements may cause significant effects on the particle size distribution and many other properties.
For this reason, separate grinding of additives and clinker may be thought as an alternative. In this study, the effects of intergrinding and separate grinding on the particle size distribution and consequently on the strength of portland
composite cements which contained natural pozzolan (trass), granulated blast furnace slag (GBFS) and limestone besides portland cement clinker were studied.
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Matyk, Tomáš. "Studium vlastností betonů s „green cementy“." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2014. http://www.nusl.cz/ntk/nusl-226718.
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The thesis focuses on collecting available information about possible ways of using and usage restriction of portland blended cements and portland cements with limestone for production of concrete. The experimental part of the thesis describes the behavior of portland blended cements and portland cements with limestone in aggressive environments. Furthermore, the thesis concerns the dependence of rheological properties of cement pastes of portland cements and portland cements with limestone on type of plasticizing additives.
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Jarolím, Tomáš. "Studium vlivu směsných cementů, zejména vápencových, na vlastnosti čerstvých a zatvrdlých betonů." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2012. http://www.nusl.cz/ntk/nusl-225683.
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This thesis focuses on collecting all available data on mixing Portland cements and especially on Portland cements with limestone. In the experimental part are compare the rheological properities of mixing Portland cements with limestone, their compatibility with plasticizing additives, witch depends on the type of additives, dosage and time, then in experimental part they are summarized monitoring of physical-mechanical properties and volume changes of concrete.
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Vianna, Guilherme Vinicius de Almeida. "Impactos na análise técnica de projetos de lavra de calcário para fabricação de cimento." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/3/3134/tde-27022018-090219/.
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O projeto de lavra em minerações de calcário para fabricação de Cimento tem se mostrado de extrema importância em um mercado cada vez mais competitivo, como o de fabricação de cimento. No Brasil, dentro das minerações de grande porte, as minerações de calcário representam cerca de 20% de todo minério explotado. Metodologias que permitam um melhorar aproveitamento da jazida mineral ganham relevância para orientar projetos de longo prazo e exigem ferramentas para a tomada de decisão sobre o investimento ou não em projetos fabris e, consequentemente, sobre a viabilidade de projetos de lavra. A metodologia proposta foi aplicada em um exemplo e apresenta uma visão global dos problemas enfrentados em minerações de calcário e que facilitará a tomada de decisão sobre investimentos com premissas reais utilizadas por companhias cimenteiras. Além das premissas, serão apresentados problemas recorrentes encontrados quando se avalia a abertura de minerações de calcário para fabricação de cimento, com diversas variáveis exógenas ao projeto, como comunidades no entorno, sítios arqueológicos, cavernas protegidas, vegetação, entre outros, além dos fatores internos ao mesmo, como os teores, o \"blend\" de camadas, a relação estéril/minério, avaliações geotécnicas, entre outros.The cement mining project for cement manufacturing has proved to be extremely important in an increasingly competitive market, such as cement manufacturing. In Brazil, within large-scale mining, limestone mining accounts for about 20% of all ore mined. Methodologies that allow a better use of the mineral deposit become of extreme importance to guide long-term projects and require tools for decision making on investment or not in manufacturing projects, and consequently on the feasibility of mining projects. The methodology proposed and applied in an application example will present an overview of the problems faced in limestone mining and will facilitate the decision making on investments with real premises used by cement companies. In addition to the premises, we will present current problems encountered when assessing the opening of limestone quarries for cement manufacturing, with innumerable variables exogenous to the project, such as surrounding communities, archaeological sites, protected caves, and vegetation, among others, besides the internal factors, such as ore grade, the blend of layers, the strip ratio, geotechnical evaluations, and others.
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Martykán, Jiří. "Sledování vývoje AFt fází ve směsných portlandských cementech s fluidním popílkem." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2016. http://www.nusl.cz/ntk/nusl-240190.
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Escadeillas, Gilles. "Les ciments aux fillers calcaires : contribution a leur optimisation par l'etude des proprietes mecaniques et physiques des betons fillerises." Toulouse 3, 1988. http://www.theses.fr/1988TOU30053.
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Il ressort de l'etude que: les proprietes rheologiques avant prise du liant sont ameliorees par l'ajout de filler, autorisant une diminution de la teneur en eau de gachage; la reactivite de la calcite est confirmee (formation de carboaluminates, diminution de l'aureole de transition); les resistances mecaniques aux jeunes ages sont ameliorees; la fragilite (fissuration. . . ) est attenuee. On envisage l'amelioration de ces procedes par addition d'un superplastifiant
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Tixier, Raphaël. "Etude mineralogique et mecanique de la phase liante de graves routieres." Toulouse 3, 1987. http://www.theses.fr/1987TOU30133.
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Comparaison des caracteristiques mineralogiques et des proprietes mecaniques de melanges equiponderaux de fillers calcaires, dolomitiques ou quartzeux avec 5 liants : ciment portland, ciment alumineux, ciment au laitier, cendres volantes chaux eteinte et fumees de silice condensees chaux residuaire. Evocation d'un nouveau liant routier, par melange de cendres volantes, fumees de silice condensees et chaux (l'additivite des proprietes se realisant pour des proportions particulieres)
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Wenglas, Lara Gilberto. "Quality evaluation of Portland cement concrete at early age with free-free resonant column." To access this resource online via ProQuest Dissertations and Theses @ UTEP, 2008. http://0-proquest.umi.com.lib.utep.edu/login?COPT=REJTPTU0YmImSU5UPTAmVkVSPTI=&clientId=2515.
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Škapa, Radim. "Optimum sulfate content of Portland cement." Thesis, University of Aberdeen, 2009. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=203836.
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Esseghaier, Kaela. "Early age hydration of Portland cement systems containing cement kiln dust." Thesis, University of Ottawa (Canada), 2009. http://hdl.handle.net/10393/28058.
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Cement kiln dust (CKD) has been used in combination with ordinary Portland cement (OPC). It has also been shown that this generally results in a reduction in strength. In some cases hydration is retarded. The objectives of this study were to use nano-calicum carbonate (CC) and metakaolinite (MK) particles in cement systems containing OPC and CKD to improve its hydration, strength, and pore structure. Calorimetry results showed that both the addition of the CC and MK particles significantly accelerated the hydration of the system. The addition of CC and the MK particles were generally effective in improving the strength of the system. Analysis of AC impedance measurements suggested that CC or MK addition resulted in a refinement of the pore structure of the system. Results from X-ray diffractometry measurements and SEM imaging were in general agreement with results obtained from the other testing techniques.
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Evans, Katherine Alexandra. "The optimum sulphate content in Portland cement." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ29389.pdf.
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Mostafa, Raqibul. "Wideband electromagnetic characterization of Portland cement concrete." Thesis, This resource online, 1995. http://scholar.lib.vt.edu/theses/available/etd-06112009-063132/.
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Fu, Yan. "Delayed ettringite formation in Portland cement products." Thesis, University of Ottawa (Canada), 1996. http://hdl.handle.net/10393/9804.
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The thesis presents the results of an extensive research program on the deterioration of Portland cement concrete due to delayed ettringite formation (DEF). The study focuses on three aspects: (i) the mechanisms of DEF; (ii) a test method to determine the DEF potential of a given cement; (iii) some preventive measures to reduce the deterioration of portland cement products due to DEF. The research work indicates that C-S-H gel will adsorb sulfate fast at high temperature resulting in quick depletion of the gypsum phase in the portland cement-water system. Sulphate absorbed at high temperature is desorbed more slowly than that adsorbed at normal temperatures. Slower release of sulfate from an internal sulfate source may be a critical condition for DEF in high temperature cured Portland cement paste. Nucleation of a crystal requires less surface energy in a crack than in the cement paste matrix. Sulfate ions, after release from the C-S-H gel, will diffuse into the nearest microcrack and react with the Al-bearing materials in the crack to nucleate and crystallize ettringite. Growth of ettringite crystals opens the crack and damages the cement products. A test method to determine the expansion potential, due to delayed ettringite formation (DEF), of portland cements initially moist-cured at high temperatures was developed. Expansion of cement mortars made with eight different portland cements was investigated. Different test parameters, such as, curing temperature, type of sand, sand/cement ratio, specimen size and pre-treatment, were studied to select the optimal test conditions and procedures. Expansion/time criteria to evaluate the DEF potential of a given cement from the results of this test method are discussed. Siliceous materials can be used in portland cement products to reduce or eliminate deterioration due to DEF. Different siliceous materials have different characteristics relevant to the reduction of the deleterious expansion. The granulated blast-furnace slag, ggbs, and Class F fly ash are more effective in reducing the DEF expansion than Class C fly ash, silica fume and natural zeolite. The expansion of the mortar containing a siliceous material appears to be much delayed. Therefore long-term expansion should be considered in the selection of a siliceous material for use in a DEF-suspect cement. Microcracks play an important role in the expansion due to DEF. Control of microcracks using wollastonite micro-fibres should reduce the expansion of a DEF-suspect cement mortar.
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Gouru, Harinath. "Laboratory evaluation of asphalt-portland cement concrete composite." Thesis, This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-12232009-020518/.
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Akkapeddi, Srikanth Schindler Anton K. "Alternative solid fuels for the production of Portland cement." Auburn, Ala., 2008. http://hdl.handle.net/10415/1432.
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Oberlink, Anne Elizabeth. "NON-PORTLAND CEMENT ACTIVATION OF BLAST FURNACE SLAG." UKnowledge, 2010. http://uknowledge.uky.edu/gradschool_theses/25.
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The purpose of this project was to produce a “greener” cement from granulated ground blast furnace slag (GGBS) using non-Portland cement activation. By eventually developing “greener” cement, the ultimate goal of this research project would be to reduce the amount of Portland cement used in concrete, therefore reducing the amount of carbon dioxide emitted into the atmosphere during cement production.
This research studies the behavior of mineral binders that do not contain Portland cement but instead comprise GGBS activated by calcium compounds or fluidized bed combustion (FBC) bottom ash. The information described in this paper was collected from experiments including calorimetry, which is a measure of the release of heat from a particular reaction, the determination of activation energy of cement hydration, mechanical strength determination, and pH measurement and identification of crystalline phases using X-ray diffraction (XRD).
The results indicated that it is possible to produce alkali-activated binders with incorporated slag, and bottom ash, which have mechanical properties similar to ordinary Portland cement (OPC). It was determined that the binder systems can incorporate up to 40% bottom ash without any major influence on binder quality. These are positive results in the search for “greener cement”.
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Dunster, A. M. "The effect of additives on Portland cement hydration." Thesis, University of Greenwich, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.377683.
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Zhao, Baoshu (Baoshu Eric). "Stabilization of Different Lead Compounds in Portland Cement." Thesis, University of North Texas, 1993. https://digital.library.unt.edu/ark:/67531/metadc278830/.
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Reid, Nola L. "Investigation of polymer-modified cement mortars." Thesis, University of Greenwich, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.258554.
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Escalante-Garcia, Jose Ivan. "The effect of temperature on the hydration of portland cement and composite cement pastes." Thesis, University of Sheffield, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.242215.
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Avşar, Hakan Doymaz Fuat. "Control, Optimization And Monitoring Of Portland Cement (Pc 42.5) Quality At The Ball Mill/." [s.l.]: [s.n.], 2006. http://library.iyte.edu.tr/tezler/master/kimyamuh/T000365.pdf.
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Halaweh, Mahmoud. "Effect of alkalis and sulfates on Portland cement systems." [Tampa, Fla] : University of South Florida, 2006. http://purl.fcla.edu/usf/dc/et/SFE0002120.
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Wilde, William James. "Life cycle cost analysis of Portland cement concrete pavements /." Digital version accessible at:, 1998. http://wwwlib.umi.com/cr/utexas/main.
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Wynn-Jones, Gareth David. "Development of a Portland cement based system for vertebroplasty." Thesis, University of Birmingham, 2013. http://etheses.bham.ac.uk//id/eprint/3914/.
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Portland cement (PC) is generally known for its various applications in the construction industry. However, since mineral trioxide aggregate (MTA), a PC based root filling material, obtained food and drug administration (FDA) approval in the late 1990’s there has been an increased interest in the use of the cement for other in vivo applications. PCs are durable, possess high compressive strengths, set in aqueous environments such as those found in vivo and have demonstrated desirable tissue responses as an endodontic sealant. The injectability of PC with various additives was investigated for use in clinical applications such as vertebroplasty (the stabilisation of a fractured vertebra with bone cement) using a syringe with a 2 mm aperture. Additives significantly improved cement injectability, decreased setting times from over 2 h to below 20 minutes while maintaining the compressive strength of the material. Cement characterisation methods including X-ray diffraction (XRD), helium pycnometry and zeta potential measurements were employed to elucidate the effect of the additives on the cement setting reaction. The biocompatibility of PC was investigated with fibroblast and bone marrow cells. The freshly mixed cement appeared cytotoxic while set cement upregulated genes associated with the osteogenic phenotype.
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Khoury, Issam S. "Impact of Base Stiffness on Portland Cement Concrete Pavement." Ohio University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1448963853.
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Al-Ghamdi, Hamed A. "Effect of curing and mix design parameters on durability of Portland cement and Portland cement-silica fume mortars in a hot-marine environment." Thesis, University of Aberdeen, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.301075.
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This study was conducted to evaluate the effect of curing and mix design parameters, such as cement content and water to cementitious materials ratio, on the strength and durability characteristics of plain and silica fume cements exposed to a hot-marine environment. Specifically, the effect of curing and mix design parameters on chloride diffusion, shrinkage and carbonation of cement mortar specimens exposed to a hot-marine environment was evaluated. The results indicated that high water to cement ratio significantly influenced the durability performance of concrete through: (1) accelerating chloride diffusion and carbonation, (2) increasing the shrinkage and weight loss, and (3) reducing the compressive strength. Similarly, increasing the cement content increased the shrinkage for a given w/c ratio. However, the chloride diffusion and carbonation were minimized and strength was enhanced due to increasing cement content. The mix design parameters, namely, water-cement ratio and cement content significantly influenced the performance of both Type I and Type V cements, while the influence of these parameters on the performance of silica fume cements was insignificant. Although Type I cement mortars performed better than Type V cement mortars, the performance of silica fume cement was the best in terms of reduced chloride diffusion, carbonation and shrinkage, and enhanced strength. The beneficial effects of silica fume cements, were however, only evident in specimens subjected to good curing. Therefore, to extend the useful service-life of reinforced concrete structures exposed to hot-marine environments, the following mix design is recommended: (i) cement content should not be less than 350kg/m3; (ii) Type I cement with 10% silica fume; (iii) water to cementitious materials ratio of not more than 0.45; (iv) good curing.
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Trauchessec, Romain. "Mélanges de ciments sulfoalumineux et Portland." Thesis, Université de Lorraine, 2013. http://www.theses.fr/2013LORR0234/document.
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Les mélanges de ciment sulfoalumineux et de ciment Portland sont des liants hydrauliques innovants permettant de moduler les propriétés des bétons, telles que la vitesse de montée en résistance ou la stabilité dimensionnelle. Les performances du liant peuvent ainsi être ajustées pour de nombreuses applications. Au-delà de cet avantage, les émissions de dioxyde de carbone liées à la production du ciment sulfoalumineux sont significativement réduites comparées à celles du ciment Portland traditionnellement utilisé. La diversité des propriétés de ces liants résulte de la variété des mélanges pouvant être réalisés à partir des deux constituants de base. Chaque mélange présente alors une cinétique d'hydratation et des propriétés qui lui sont propres. Par exemple, certains liants sont expansifs mais présentent une montée en résistance progressive, tandis que d'autres sont stables dimensionnellement alors que leur résistance stagne après quelques jours d'hydratation. L'identification et le contrôle des paramètres à l'origine de ces comportements sont donc nécessaires pour garantir des propriétés spécifiques à un usage donné : chape, mortier de réparation, élément préfabriqué, etc. C'est l'objectif de cette étude qui s'attache à déterminer la cinétique, la minéralogie et les propriétés associées à l'hydratation de trois mélanges contenant 85 %, 70 % et 40 % de ciment Portland. Les essais entrepris ont aussi permis d'aboutir à une modélisation thermodynamique des mécanismes d'hydratation. L'impact de la composition du ciment Portland est également étudié. Enfin, il est montré que l'anhydrite et la chaux sont deux leviers qui modifient radicalement le processus d'hydratation et permettent ainsi d'adapter les propriétés d'un mélange aux exigences de son utilisationBlends of ordinary Portland cement and sulfoaluminate cement are innovative hydraulic binders allowing control of concrete properties such as hardening speed or dimensional stability for specific applications. Moreover, carbon dioxide emissions linked to sulfoaluminate cement are significantly reduced compared to ordinary Portland cement. The binder properties can be adjusted due to the diversity of blends conceivable with these two constituents. Each blend has its own hydration kinetic and properties. For example, some blends are expansive and the hardening is progressive whereas other mixtures are dimensionally stable but their strength stagnates after few days. Identification and control of the parameters responsible of these comportments are necessary in order to guaranty specific properties for each application: screed, repairing mortar, etc. This is the aim of this study which described the hydration kinetic, the properties and composition of three blends containing 85 %, 70 % and 40 % of Portland cement. These experiments are completed by thermodynamic modeling of the hydration mechanisms. The effect of the Portland cement composition has also been tested. Finally, it's shown that anhydrite and calcium hydroxide are two key parameters which modify radically the hydration process and allow the properties adjustment required for the blend used
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Schmidt, Heinrich. "X-ray diffraction study of high temperature reaction products in the barium oxide-silica-alumina-ferric oxide system." Thesis, Pretoria : [s.n.], 2001. http://upetd.up.ac.za/thesis/available/etd-03072007-132505.
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Swart, Dustin W. "The utilization of alternative fuels in the production of Portland cement." Auburn, Ala., 2007. http://repo.lib.auburn.edu/07M%20Theses/SWART_DUSTIN_26.pdf.
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Svinning, Ketil. "Design and manufacture of Portland cement Application of statistical analysis." Doctoral thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for materialteknologi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-14948.
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The purpose of the work is to enable design and manufacture of cement with emphasis on the quality and the properties of cement. Data used in the design and manufacture were collected from predictions of properties and characteristics of cement. The properties of cement were predicted from its characteristics and from the production conditions in cement kiln and mill. The cement characteristics were in some investigations predicted from the production conditions. The design was based on sensitivity analysis focusing the influence of the characteristics and production variables, x, on the properties, y. The influence was analyzed by predictions of y from the simulated variation in x. In cases there were correlation within observation matrix X, the simulations were constrained by the latent structure of X. The simulations were in the form of optimization of the function for prediction of y. The optimal solutions of the production variables were then implemented in the manufacture of cement. The prediction models were evaluated by multivariate data analysis by using partial least square regression (PLS). PLS is a member of the bilinear class of methods. The method compresses the observation matrix X to its most relevant factors and using these compressed variables as regressors for y. In the thesis the compressed variables were sometimes called PLS-components and sometimes latent variables. Two types of sensitivity analysis for the examination of influences of the x-variables on y were applied. The first is based on comparison of the size and certainty of the regression coefficient from PLS on scaled and weighted x. The second was based on predictions of y from simulated variation in x. The influence of a single x-variable or a latent variable was valued or ranged from the variation of predicted y relative to the confidence intervals of y. The development of a program for optimization was an important part of work presented in the thesis. The optimization was in the form of linear programming where the regression function of y was optimized but constrained by the latent variables and upper and lower limits of at least one of the x-variables. The purpose was not to focus only on the methods but also to apply the methods on real data from production and characterization of cement for prediction of the quality and the properties of cement. Two investigations were performed on pure observations of X and Y. In the first investigation three PLS-models were evaluated for prediction of the three properties; amount of water required to achieve standard consistency, setting time and compressive strength at 1 day from production conditions in a cement mill. In the second investigation, a PLS-model was evaluated for predictions of compressive strength up to 28 days from characteristics of the cement. The observation X was made up by four submatrices representing three different types of characteristics, the first one representing the mineralogy of the clinker part of the cement, the second the particle size distribution and the third and fourth superficial microstructure of cement. The mineralogy characterized by X-ray diffraction (XRD) analysis could be related to the production conditions in the cement kiln. The particle size distribution and superficial microstructure, the latter characterized by thermogravimetric analysis, could be related to the production conditions in a cement mill. From the observation X matrix an artificial observation matrix was made for predicting potential compressive strength of clinker from the mineralogy. The original variation in the mineralogy in the new artificial matrix was maintained, while the other variables were kept constant and equal to their mean values. The mineralogy was represented by XRDcurves, which are characterized as spectral data, in two selected 2 _ ranges. Further, the spectral data were optimized to min and max potential compressive strength. In addition, they were interpreted qualitatively with respect to the variation in the mineralogy. The spectral data from thermogravimetric analysis included in PLS, were the differential form of a mass loss curve recorded during the analysis. In addition to examining the influence of submatrices or blocks to on the properties by sensitivity analysis, multi-block regression methods were applied. By application of multi-block methods, the part of the characteristics or the microstructure that influences the properties could be found directly from the regression analysis. Finally, the production conditions in a cement mill and a cement kiln were optimized to achieve optimal cement properties. Amount of water required to achieve standard consistency and setting time were predicted from production conditions in a cement mill, and potential compressive strength of clinker up to 28 days were predicted from production conditions in a cement kiln. The production conditions were optimized to achieve min and max values of the properties. The microstructure or the characteristics were predicted from the optimal production conditions to explain the influence of the production conditions on the properties mechanistically and chemically. The main contributions in the form of papers in this thesis are (the roman numerals refer to the list of papers at the end to this chapter): 1. Developing methods for model-based optimization based on PLS, sensitivity analysis, prediction and linear programming. A case of demonstration was optimizing compressive strength of cement from variation of particle size distribution of cement [I-III] 2. Modelling compressive strength up to 28 days of cement on the characteristics of cement, predicting and optimizing potential compressive strength from the mineralogy of clinker [IV-V] 3. Presenting the principles and application of multi-block methods in cement production [VI-VII] 4. Optimizing production conditions to achieve optimal cement properties [VIII-IX] The use of multivariate data analysis, sensitivity analysis and model-based optimization is very useful in the design and manufacture of cement. The methods enabled tailoring of cement aiming at target values of properties like compressive strength, setting time and initial flow properties. The tailoring can be based on the variables representing the characteristics of cement as well as the variables representing the production conditions in the cement kiln and the cement mill. The max values of the compressive strength at 1 and 28 days were achieved by optimizing the production conditions in the kiln giving the optimal mineralogy for achieving max strengths. Optimal values of cement properties at early ages were achieved by optimizing the production conditions in the cement mill giving the optimal superficial microstructure.
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Ishee, Charles. "Evaluating the performance of Portland cement under differing hydration conditions." Thesis, McGill University, 2011. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=104814.
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The objective of this work was to examine the hydration performance of Portland cement with variations in their Tricalcium Silicate and Tricalcium Aluminate phases. The performance of Portland cement is affected by its particle size, chemistry, morphology, water availability, thermodynamic reaction rates, and age at which the materials are tested. The majority of research on Portland cement hydration has thus far evaluated each of its different components independently by examining how those phases react with water over time. However, Portland cement has many phases that are all reacting simultaneously depending on many different factors. How the different phases react while part of the entire system, including how their reactions affect the reactions of other components in the system, needs to be further investigated in order to determine how a true cement can be expected to behave during hydration. Laboratory research focused on the establishment of early age hydration products and their relationship to the development of strength, shrinkage, and heat production. The experimental program was designed to contrast the performances of the different cements at various temperatures, water availabilities, degrees of grinding, and times. The ultimate goal was to provide the basis for a predictive model capable of estimating the phase composition of a hydrated Portland cement under specified conditions.L'objectif de ce travail était d'examiner la capacité d'hydratation du ciment Portland en apportant des variations dans ses étapes de silicate tricalcique et d'aluminate tricalcique. La performance d'hydratation du ciment Portland est affectée par sa dimension particulaire, sa composition chimique, sa morphologie, la quantité d'eau présente, la vitesse des réactions thermodynamiques ainsi que de l'âge auquel les matériaux sont testés. Jusqu'à maintenant, la majorité de la recherche sur l'hydratation de ciment Portland a étudié chacun de ces éléments indépendamment en évaluant leurs phases de réaction avec l'eau sur une période de temps déterminée. Cependant, le ciment Portland possède beaucoup d'étapes qui réagissent tous simultanément selon plusieurs facteurs différents. Comment ces phases réagissent tous ensemble en faisant partie d'un système entier, incluant comment leurs réactions affectent les réactions des autres ingrédients dans ce même système, doit être étudié plus en profondeur afin de déterminer comment un ciment réel peut se comporter pendant la période d'hydratation. Les expériences de laboratoire de ce projet se sont concentrées sur l'apparition des produits d'hydratation en période précoce et de la relation de ces produits avec le développement de la force, du rétrécissement, et de la production de chaleur. La portion expérimentale de ce projet a été conçue pour comparer la performance de différents ciments selon des variations de températures, de la quantité d'eau, des degrés de meulage et de temps. L'objectif primaire de ce projet était de définir les éléments nécessaire pour créer un modèle prédictif capable d'estimer la composition de phase du ciment Portland hydraté dans des conditions spécifiques.
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Tank, Suresh Bhagwanji. "The use of condensed silica fume in Portland cement grouts." Thesis, University College London (University of London), 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.307794.
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Harrington, Pamela P. "Post retention with mineral trioxide aggregate and accelerated Portland cement." Morgantown, W. Va. : [West Virginia University Libraries], 2005. https://etd.wvu.edu/etd/controller.jsp?moduleName=documentdata&jsp%5FetdId=4035.
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Thesis (M.S.)--West Virginia University, 2005.Title from document title page. Document formatted into pages; contains viii, 57 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references (p. 34-39).
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Ghazizadeh, Seyedamirhossein. "Understanding the behaviour of graphene oxide in Portland cement pastes." Thesis, University College London (University of London), 2018. http://discovery.ucl.ac.uk/10058950/.
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Graphene oxide is a distorted graphene mono-layer in which a fraction of carbon atoms have been oxidised into various functional groups, such as carbonyl and carboxyl. Graphene oxide has the potential to enhance the low tensile strength of Portland cement matrices, but research is required to understand how it behaves in blends with cement and water. This thesis investigates the behaviour of graphene oxide in pastes made with either mineral alite (the main constituent of Portland cement), clinker (alite with aluminate and ferrite minerals) or Portland cement. This study shows that graphene oxide is susceptible to agglomeration in alite and Portland cement pastes. Various experimental techniques, namely isothermal calorimetry, inductively coupled plasma atomic emission spectroscopy, X-ray diffraction, Fourier-transform infrared spectroscopy, and thermogravimetric analysis were used to establish why graphene oxide agglomerates in the environment of cement pastes. Results show that the carboxylate sites in graphene oxide form complexes with multivalent cations (mainly calcium) in the pore solution of cement pastes. This reaction bridges the graphene oxide layers, causing their agglomeration. In a separate reaction, the hydroxide ions present in the paste solution deoxygenate graphene oxide, reducing it into an almost hydrophobic material. Calorimetry measurements showed that graphene oxide significantly retards clinker hydration, whereas it accelerates the hydration of alite and Portland cement only marginally. Retardation occurs as graphene oxide binds to the surface of hydrating clinker grains, while acceleration results from a seeding effect in which graphene oxide provides extra surface for the nucleation and growth of hydration products. In Portland cement pastes, sulphate ions released from the dissolution of gypsum prevent graphene oxide from retarding the hydration. Simulations using a boundary nucleation-growth model confirmed that graphene oxide is not particularly active as a nucleation surface in alite paste and behaves in a similar way to inert fillers, such as quartz. Mechanical tests indicated that graphene oxide slightly strengthens hardened cement pastes. This effect is shown to be directly related to the change of cement hydration degree, as opposed to the reinforcing effect previously proposed in the literature. Finally, a simple strategy was proposed to counteract the agglomeration of graphene oxide in cement pastes. The method uses organic acids and copolymers that mitigate the reaction of graphene oxide with divalent cations and hydroxide ions. These allowed the dispersion of graphene oxide in alite paste for the first time.
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Ludvig, Péter. "Synthesis and characterization of portland cement manufactured with carbon nanotubes." Universidade Federal de Minas Gerais, 2012. http://hdl.handle.net/1843/BUOS-96DFJ6.
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Portland cement (PC) is one of the most consumed products of the world. Its derivates (concrete, mortar, paste) have good compressive characteristics, but on the other hand have poor tensile behavior. Carbon nanotubes have exceptionally high tensile strength and are
therefore candidates for structural reinforcement of cement materials. Many tentative have been reported to develop composites with the physical mixture of high quality nanotubes and cement. These processes today are still unviable for large scale production of construction
material. The problems are linked to the scale and costs of production and the dispersion and bond of the nanotubes to the cement matrix. In order to solve these problems in present work an in-situ synthesis process was developed to produce nanotubes and nanofibers on clinker
and silica fume particles. Steelmaking by-products, such as steel mill scale and converter dust were also added to improve product characteristics. The synthesis products were characterized by scanning electron microscopy, thermogravimetric analysis and loss on ignition. The products showed highly heterogeneous morphology. An in-situ functionalization process was also developed based on ammonia. The nano-structured materials were added to Brazilian CP-III and CP-V type cements in 0.3 % concentration to perform common physical and chemical cement analysis. Setting time of CP-V suffered a slight delay, but other characteristics were not altered significantly after the addition of nano-structured clinker. Mortars were prepared in order to determine compressive and flexural or splitting tensile strength of the composites.
Gains in the compressive and tensile strengths were observed of mortars incorporating 0.3 % nanotubes prepared with a combined polycarboxylate and polynaphtalene and a lignosulfonate based plasticizer. Positive results were also observed with the use of hydrogen
peroxide as functionalizing agent. The addition of nano-structured silica fume also resulted in increase of the mechanical strength of the composites. BET and helium pycnometry analysis of the mortars showed an increase in specific surface area and reduction of mean pore
diameter of the composites.O cimento Portland (PC) é um dos produtos mais consumidos no mundo. Seus derivados (concreto, argamassa, pasta) apresentam características satisfatórias quanto à compressão, entretanto o mesmo não ocorre com relação à tração. Os nanotubos de carbono (NTCs) possuem elevada resistência à tração, sendo deste modo candidatos para reforçar estruturalmente materiais cimentícicos. Várias tentativas foram realizadas no mundo para desenvolver processos envolvendo a produção de compósitos a partir da mistura física de cimento e de nanotubos de alta qualidade. Atualmente estes processos são ainda inviáveis para produzir material de construção em grande escala. Os problemas a isto associados estão relacionados à escala e custo de produção, além da dispersão e ligação dos nanotubos na matriz de cimento. Para tentar resolver estes problemas, neste trabalho foi desenvolvido um processo de síntese in-situ de nanotubos e nanofibras de carbono em clínquer e sílica ativa. Além disso, resíduos da siderurgia como carepa de laminação de aço e pó de aciaria foram utilizados para melhorara as características dos produtos. Os produtos da síntese foram caracterizados por microscopia eletrônica de varredura, por análise termogravimétrica e por resíduo por queima. Estes produtos apresentaram grande heterogeneidade em morfologia. Foi desenvolvido também um processo de funcionalização in-situ dos nanotubos via amônia. Os materiais nano-estruturados foram adicionados aos cimentos CP-III e CP-V em uma concentração de 0,3 % para realização de análises físico-químicas convencionais de cimento. O tempo de pega apresentou um leve aumento no cimento CP-V, mas os demais parâmetros não sofreram alterações significativas pela adição de clínquer nano-estruturado. Argamassas foram preparadas para testar as resistências à compressão e à tração dos compósitos, este último por flexão ou por compressão diametral. Aumentos nas resistências à compressão e à tração foram observados em argamassas preparados com 0,3 % de nanotubos em relação ao peso do cimento, e com aditivos plastificantes a base de policarboxilato e polinaftaleno além de lignosulfonato. Resultados promissores também foram obtidos com o uso de peróxido de hidrogênio como agente de funcionalização. A adição de sílica ativa nano-estruturada também provocou aumento de resistência mecânica dos compósitos. Análises por BET e por picnometria a hélio mostraram aumento da área superficial específica e redução dos diâmetros dos poros dos compósitos.
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Monts, M. Scott. "Use of a Portland Cement Accelerator with Mineral Trioxide Aggregate." VCU Scholars Compass, 2004. http://scholarscompass.vcu.edu/etd/805.
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The use of Mineral Trioxide Aggregate (MTA) is gaining popularity among clinicians. Despite the many ideal qualities it possesses, it is often difficult to manipulate and often requires a second appointment for placement of a restoration to allow for setting. If the time to set of MTA can be accelerated to a single appointment time frame without significantly altering its properties, then MTA may gain even wider acceptance. The purpose of this study is to identify the percentage of a Portland Cement Accelerator (PCA), that when added to MTA, will decrease the time to set of MTA towards a single appointment time frame. Ten Teflon sample molds were prepared to hold 20 standardized chambers in each. Three sample molds were prepared with a 5.0% (by weight of MTA) accelerator, 3 with 10.0% accelerator and 3 with 15.0% accelerator mixed with MTA and water. Another sample mold contained a mixture of MTA and water only and acted as the control. Samples were tested using a dial indicator microgauge apparatus that measured the depth of needle penetration starting at 2 minutes and then every minute up to 15 minutes. Samples were also tested at 3, 4, 24, 48 and 72 hours. A mixed-model repeated measures ANOVA showed the four accelerator groups were significantly different and there was a significant time trend. The 5.0% accelerator group set significantly faster compared to the 15.0% and the control at 15 minutes or less (p<0.05). In conclusion, it appears that 5.0% PCA when added to MTA can accelerate the setting reaction.
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Fletcher, James George. "Borate fluxes in ordinary Portland cement production : a feasibility study." Thesis, University of Aberdeen, 1991. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU527393.
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The energy required to develop and process the high temperature phases essential to the performance of ordinary Portland cement (OPC) and to process the resulting clinker, represents a substantial fraction of the overall energy input. Both chemical engineering and chemical approaches have been used to reduce specific energy inputs. In this thesis the chemical engineering advances are reviewed, and the use of fluxes to reduce production costs is extensively investigated. Investigation of borate-assisted clinkering reactions forms the basis of this thesis, and the subject is addressed as follows: (i) Investigation of the strcutures, polymorphism and stabilisation of C3S and C2S (literature review, theoretical and experimental research). On the basis of this research, a structural model was proposed for alpha-C_2S and a novel transformation mechanism was proposed for the alpha'C2 Sphase transition. (ii) Review of the physical properties of the clinkering melt and its modification by fluxes or mineralisers (literature review). This review revealed that borates have potential as fluxing agents, because they reduce both the surface tensions and viscosity of the melt. (iii) Investigation of the CaO-SiO2-B2O3 phase equilibria and its resultant effect on clinker mineralogy (literature review and experimental research). This investigation revealed that borates not only act as fluxes but in addition they have a mineralising effect, which alters the C3S:C 2S ratio in favour of dicalcium silicate. The main conclusion of this thesis is that the use of borates as fluxing agents in ordinary Portland cement production is disadvantageous: borates rapidly reduce the amounts of the essential constituent tricalcium silicate, and can hence be classed as deleterious mineralisers.
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Mbasha, Migabo Willy. "The effect of portland cements and superplasticisers on the rheology of cement paste." Thesis, Cape Peninsula University of Technology, 2015. http://hdl.handle.net/20.500.11838/2169.
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Dissertation submitted in partial fulfilment of the requirements for the degree MTech Degree in Civil Engineering in the Faculty of Engineering at the Cape Peninsula University of TechnologySelf-compacting concrete is very sensitive to variation in cement properties and to the interaction between cement paste and additives such as superplasticisers. The assessment of these interactions can be done rheologically but there is as yet no consensus on how to evaluate the rheological properties (yield stress and viscosity) of cementitious materials. In addition, there is no clear understanding of the dependency of these rheological properties on early hydration, evaluations which are recommended to be done at paste scale. The evolution of rheological parameters in the early stage of hydration, of four CEM I 52.5N cements manufactured at different factories in South Africa, and their interaction with two different commercial superplasticisers (SPs) were investigated using three different rheometric techniques: conventional flow curve from hysteresis loops, amplitude sweep in oscillation mode and construction of flow curve. Amplitude sweep, time sweep, viscosity-time sweep as well as thixotropy tests were conducted to investigate the effect of hydration and the rate of rebuilding of each cement in the presence and absence of SP. The experiments were done on a MCR51 rheometer with roughened parallel plates under controlled temperatures and relative humidity.
PPC Cement
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Jensen, Hans-Ulrich. "The effect of sea-water on the hydration of Portland cement and fly ash cement blends." Thesis, Imperial College London, 1988. http://hdl.handle.net/10044/1/47124.
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Clark, Simon Martin. "Development of an energy-dispersive powder diffraction facility for the study of phase transitions and chemical reactions." Thesis, Birkbeck (University of London), 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.337929.
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McCabe, Christopher C. "An investigation into the influence of metakaolin on the properties of concrete." Thesis, Queen's University Belfast, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.247338.
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Jupe, Andrew Charles. "Development of X-ray and neutron diffraction methods for cement research." Thesis, Birkbeck (University of London), 2000. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.392173.
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Darraugh, Natalie Ainsworth. "Air void characterization in fresh cement paste through ultrasonic attenuation using an immersion procedure." Thesis, Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/31822.
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Thesis (M. S.)--Civil and Environmental Engineering, Georgia Institute of Technology, 2010.Committee Chair: Jacobs, Laurence; Committee Co-Chair: Kurtis, Kimberly; Committee Member: Kim, Jin-Yeon. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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Rubert, Sílvia. "Contribuição ao estudo de cimentos supersulfatados: formulação e mecanismos de hidratação." Universidade Tecnológica Federal do Paraná, 2015. http://repositorio.utfpr.edu.br/jspui/handle/1/1242.
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Nos últimos anos, uma atenção considerável tem sido dada para o desenvolvimento de cimentos especiais, capazes de reduzir as emissões de CO2 e de energia, bem como o consumo de calcário. Cimentos supersulfatados são compostos principalmente de escória de alto forno (80-90%), sulfato de cálcio (10-20%) e um ativador alcalino, tal como o cimento Portland (cerca de 5%) ou hidróxidos de metais alcalinos. Os cimentos supersulfatados (CSS) foram usados nos anos entre 1950- 1960 na Europa, especialmente para aplicações em concretos, mas o seu menor ganho de resistência em idades iniciais limitava a sua aplicação comercial. Mais tarde, mudança no processo de fabricação do ferro gerou implicou na geração de escórias que deixaram de apresentar o conteúdo mínimo de Al2O3 exigido para CSS, levando a sua utilização alternativa em misturas com cimento Portland (Cimento de alto forno). Recentemente, a norma para o cimento supersulfatado na Europa foi substituída pela norma EN 15743 (2010), no entanto, o mecanismo de hidratação bem como a sua composição ótima não são bem compreendidos. Nesta pesquisa, o efeito do tipo e teor de ativador alcalino (hidróxidos) e das proporções de escória e anidrita foi estudado. Os hidróxidos de cálcio e potássio foram estudados em teores de 0,2, 0,5 e 0,8% em formulações de CSS contendo entre 80 - 90% de escória de alto-forno e 10-20% de sulfato de cálcio (anidrita). Através de análise de resistência à compressão verificou-se que os teores de ativadores alcalinos apresentaram maior influência em comparação às proporções de anidrita e escória. Argamassas moldadas com KOH como ativador alcalino, com 0,2 e 0,5% apresentaram os maiores valores para resistência à compressão enquanto que as argamassas elaboradas com Ca(OH)2 apresentaram maior valor 0,8%. Todos os cimentos elaborados com utilização de 0,5% de KOH como ativador alcalino, e as proporções com 85% de escória e 15% de anidrita encontram-se dentro das exigências da EN 2010. Entretanto, nenhum dos cimentos elaborados com 0,8% de KOH atingiram o limite, apenas aqueles elaborados com 0,8% de Ca(OH)2. As medidas calorimétricas confirmaram que a utilização de KOH fornece maiores fluxos de calor e maior calor acumulado quando comparado com Ca(OH)2. Para ambos os ativadores, maiores teores aumentaram o fluxo de calor e o calor acumulado. As análises microestruturais (DRX, TG/DTG, MEV) comprovam que os principais produtos de hidratação dos cimentos supersulfatados são as fases de etringita, gipsita e C-S-H, e também que o teor de ativador alcalino influência na disposição de anidrita (sulfato de cálcio) na matriz sólida de cimento. A anidrita ue deveria ser consumida para formação de etringita, quando muito solúvel, propicia a maior formação da fase hidratada gipsita.In recent years, considerable attention has been given to the development of special cements that can reduce CO2 emissions and energy and the consumption of limestone. Supersulfated cement are mainly composed of blast furnace slag (80- 90%), calcium sulfate (10-20%) and an alkaline activator such as Portland cement (around 5%) or alkali metal hydroxides. The supersulfated cements (SSC) were used in the years between 1950 to 1960 in Europe, especially for applications in concrete, but its lower gain strength at initial age limited their commercial application. Later changes in iron manufacturing processes generated slag which Al2O3 no longer met the requirement of minimum content required for SSC, leading to its alternative use mixtures of Portland cement (blast furnace cement). Recently, the standard for Europe supersulfated cement was replaced by EN 15743 (2010), however, the hydration mechanism and its optimum proportion are not well understood. In this study, the effects of the type and content of the alkali activator (hydroxides) and the content of slag and anhydrite were studied. The calcium and potassium hydroxide were studied in 0.2, 0.5 and 0.8% with SSC formulations containing 80 - 90% blast furnace slag and 10-20% sulfate calcium (anhydrite). Compressive strength tests showed that the content of alkaline activators influenced more than slag/anhydrite content. Mortars made with KOH with of 0.2 and 0.5% presented the highest compressive strength values; however, mortars made prepared with Ca(OH)2 presented the highest values with 0.8%. All cements prepared with 0.5% KOH as alkaline activator containing 85% of slag and 15% of anhydrite reached the EN 15743 requirements. The calorimetric measurements confirmed that the KOH provided higher heat flow rate and increased the total heat in relation to Ca(OH)2. The microstructural analysis (XRD, TG/DTG, SEM) confirmed ettringite, gypsum and C-S-H as main phases. The anhydrite should be consumed for the formation of ettringite, however when very soluble, provided a higher formation of gypsum phase.