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The determination of the composition of refractory material by X-ray fluorescence.
Janča, Martin ; Šilerová, Iva (referee) ; Šiler, Pavel (advisor)
The goal of this Bachelor thesis is to find the right way for the analysis of the refractory materials that would be accurate and could be repeated. The ideal method that would help us achieve our goal seems to be the fluorescent spectrometric analysis. This method is used very often in case of instant control of the quality of production in the cement and other heavy industry enterprises. Using the fluorescent spectrometric analysis comes with one issue, which is the presence of many distorting interferences. From this particular reason it is necessary to identify these interferences and then find the ideal solution of their elimination. Because of the possibility to have the sample in any shape or form at the x-ray florescent spectrometer it was necessary to choose the right method of preparing the sample for the analysis as well as choose the right parameter for the measuring itself and for the elimination of undesirable interferences.
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Possibilities of using of ultra fine content of fly ash from clasical coal combustion
Havelka, Jaroslav ; Šiler, Pavel (referee) ; Opravil, Tomáš (advisor)
This thesis deals with the study of ultra fine content of fly ash from clasical coal combustion. It focuses mainly on the determination of properties of the fly ash – pozzolanic activity, chemical composition, particle size distribution and specific surface area. Possibilities of use of these fly ash were studied by preparation of cement mixtures with the fly ash and subsequent evaluation of physical properties and phase composition of the resulting composites. Phase composition was examined by x-ray powder diffraction.
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The effect of particles size on the properties of mortars.
Sehnal, Tomáš ; Krátký, Josef (referee) ; Šiler, Pavel (advisor)
The consumption of concrete as a building material is still increasing over the world. Concrete production is closely associated with CO2 and other greenhouse gases emissions. The reduction of these emissions can be achieved by a higher utilization of secondary raw materials in cement mixtures. This bachelor work is focused on the using of secondary raw material, finely ground granulated blast furnace slag and fly ash from fluidized bed combustion and high temperature combustion. The properties of milling pure cement and cement mortars with addition of secondary raw material will be measured. Compressive strength, flexural strength, and calorimetric measurement will be performed for these prepared mortars.
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The influence of aggregate on the properties of high performance concrete.
Bezděk, Ondřej ; Krátký, Josef (referee) ; Šiler, Pavel (advisor)
This bachelor thesis is focused on the influence of aggregates on the mechanical properties of high-performance concrete. The flexural strenght and the compressive strenght were observed after 1, 7 and 28 days. The process of hydratation was monitored using isoperibolic calorimetry. Laser particle size analysis of aggregates was also performed. As materials were used: Portland cement CEM I 42,5 R-Sc Mokrá, finelly ground silica sand, calcinated bauxite, fine test sand ČSN EN 196-1, medium test sand ČSN EN 196-1, rough test sand ČSN EN 196-1 and polycarboxylate superplasticizer Glenium Ace 40.
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Self-leveling floors based on secondary raw materials
Darakevová, Michaela ; Šiler, Pavel (referee) ; Opravil, Tomáš (advisor)
The work deals with the use of secondary raw materials in the self-leveling floor systems when used as a secondary raw material perform here especially classic ash, boiler slag and gypsum from flue gas. Work is looking for ways in as much as possible to replace conventional materials used in self-leveling flooring systems, secondary energy products. The aim of this work is to determine the optimal amount and ratio of secondary raw materials in self-leveling flooring compounds so that they are maintained or improved standard properties of these compounds reported in the standards. The work is divided into several points, the first point was first sought appropriate composite binder, where it was used as aggregates reach a standard sand. At other points the sand was then replaced by secondary materials. Were also tested ingredients to influence the rate of cooling, or for the onset of the initial strength.
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Possibilities of utilization of solid residues from fluidized bed combustion for preparation of composite Portland cements
Beranová, Denisa ; Šiler, Pavel (referee) ; Opravil, Tomáš (advisor)
The bachelor thesis deals with possibilities of utilization of solid residues from fluidized bed combustion of coal, bed and filter ash, to be used in the production of composite Portland cements. 6 ash types were investigated, of which 3 were bed ash (finely ground) and 3 were filter ash colected from Ledvice, Tisová and Poříčí K8 power plants. The chemical composition of the ash collected was determined and the progress of a hydration reaction monitored, and then samples mixed with Portland clinker were prepared. Their respective compressive strength and flexural strength were then analysed and observations made on the hydration and composition of products of the hydration reaction. Finally the results of selected mixtures were verified with prepared standardized mortars.
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Reinstating of concrete floors on alkalic way
Straděj, Tomáš ; Šiler, Pavel (referee) ; Opravil, Tomáš (advisor)
The work deals with the reinstanting of concrete floors by alkali way. The section deals with concrete, its development, production, use, and substances from which it is made. The second part deals with connective systems based on portland cement concrete flooring applications and possibilities of their reinstanting through alkaline. The thesis proposal for the reinstanting of the floor and describes the laboratory experiment.The last part contains information of practical measurements and conclusions drawn regarding the suitability of repair methods and resources for concrete floors different alkali and their combinations.
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Mosaic geopolymeric thin-film plasters for decorative applications
Svidroňová, Barbora ; Šiler, Pavel (referee) ; Šoukal, František (advisor)
This bachelor thesis deals with preparation of mosaic geopolymeric plasters, used fillers and it observes their influence on the final properties of geopolymeric plaster. The aim of the study is the selection of proper raw materials for filler, the determination of optimal filler-to-sand ratio and the preparation of plaster with proper shade of colour. In experimental part, during the detection of adequate ratio of raw materials, there were prepared beams from several types of metakaoline, sand, water and water glass. The beams were tested for compressive strength and bending. The blasters themselves were watched for their applying, hardness, shades of colour and efflorescence.
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The effect of fly ash on the properties of cement mortars.
Bayer, Petr ; Brandštetr, Jiří (referee) ; Šiler, Pavel (advisor)
The consumption of the cement for construction industries is increased every year. That is associated with greenhouse gas emissions, especially carbon dioxide CO2. Reduction of greenshouse gas emissions can be achieved by maximisation of the use of cementitious and pozzolanic by-products. As by-product could be used blast furnace slag and fly ash. My bachelor’s thesis is focused on the possibility of the partical replacement of the cement by fly ash. High temperature and fluidized fly ashes will be tested. The goal is to examine the behavior of the cement mortars in compensation of 10, 20, 40 and 60 % by weight of cement by fly ash. The compressive and flexural strength and isoperibolic calorimetry measurement were performed.
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