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Testing of binders of thermal insulations for specific applications on technical appliances
Maňák, Jan ; Kulísek, Karel (referee) ; Petránek, Vít (advisor)
This work focus on testing alcali-activated binders for thermal insulation which could be used for special industry devices. In the beginning of this work is presented example of thermal energy storage where these specific alcali-activated materials can be used. Ensuingly two construction with thermal energy storage tanks are mentioned. Most of the interest aims on ageing and rheological properties of alcali-activated binder. Some rheological methods are also discussed. In the end of this work is added practical experience.
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Influence of type of base sand on strength of geopolymer sand mixture
Kudr, Martin ; Šupálek, Milan (referee) ; Cupák, Petr (advisor)
The goal of this research is to find out the effect of different types of opening material on bending strength geopolymer’s moulding mixture. Four different silical opening material were used along with two types of binder. To solve the selected problem I have used the test of bending strength. At first I have prepared the moulding mixture and after its induration, I have tested the bending strength. The times were always the same 60, 120 and 1440 minutes. The highest level of bending strength was achieved at opening material SH-34 when using binder Geopol 618. The value of bending strength level was 0,881MPa. The results of this research could help the foundries during implementing technology of geopolymer moulding mixture, which would help particulary when looking for a proper opening material.
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Artificial stone - methods of preparation and properties
Pluskalová, Barbora ; Bayer, Patrik (referee) ; Rovnaník, Pavel (advisor)
The aim of the thesis „Artificial stone – Methods of preparation and it´s properties“ deals with the various methods and issues concerning the preparation of artificial stone. The thesis presents the summary of materials and various methods suitable for the preparation and points out mechanical properties, including durability of material, which serves as an alternative to natural stone. Further on, the thesis deals with the studies of binding systems based on geopolymers, which are used for the artificial stone preparation. This part of the thesis is associated with the experimental part, which is aimed at choosing the suitable mixing ratio of binder to aggregate in the artificial stone based on metakaolin geopolymer. According to the results of mechanical tests and aesthetic impression the author chose the best composition and then created a decorative element.
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Color possibilities of artificial sandstones based on geopolymers
Lattenberg, Pavel ; Kalina, Lukáš (referee) ; Opravil, Tomáš (advisor)
This thesis deals with the possibility of preparing artificial sandstone based on geopolymer matrix and ways to achieve a natural appearance and good mechanical properties. The theoretical part is devoted to the current state of knowledge in the field of geopolymers and their recovery potential, but also the natural sandstone and its geographic diversity. The practical part deals with the preparation of various types of binding systems based on metakaolin, ground blast furnace slag and water glass. Their comparison, and the possibility the appearance and characteristics change in the composition of the filler.
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Fibre coposites with alkali -activated slag matrix
Pluskalová, Barbora ; Bayer, Patrik (referee) ; Rovnaník, Pavel (advisor)
This master thesis is concerns the preparation of Alkali Activated Materials, specifically Alkali Activated Slag (AAS), with the addition of fiber reinforcement. Alkali Activated Materials have great potential for use in construction practice. However, their use is limited by certain undesirable properties, which can be diminished by adding fiber reinforcement. This thesis deals with the influence of carbon fibers (2 % by weight of the binder) and carbon nanotubes (0,2 % by weigh of the binder) on the mechanical properties, microstructure and shrinkage of AAS. The results of the experiments which were carried out correspond with the literary research. Conclusions of this thesis agree with research published in original scientific papers.
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The possibilities of using of foundry filter ash
Solik, Jaroslav ; Šoukal, František (referee) ; Opravil, Tomáš (advisor)
This thesis explores the posibility of using of foundry filter ash for production of inorganic composite materials, that could be used primary in the construction industry. The thesis is divided into theoretical and experimental section, where theoretical section contain literature review of used materials and the experimental section summarizes the results of laboratory tests performed on tested mixture based on portland and alumina cement with various content of foundry filter ash. For comparison was also used another foundry waste - foundry sand. Prepared test bodies with dimension of 40 x 40x 160 mm was subjected to mechanical strength tests and the influence of amount of foundry waste on the strenght of the prepared mixtures was monitored. Next the thesis deals with possibilities of alkaline activation of foundry waste, where sodium water glass, sodium hydroxide and commercially supplied baucis L 160 component B were used as alkaline activator. These test mixtures were also subjected to mechanical strenght tests and the influence of amount of foundry waste on the strenght was observed too. The analysis of input materials were performed by XRF, TG – DTA – EGA and XRD powder diffraction methods. All strength tests were tested by testing equipment desttest 4310.
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Thin-film geopolymeric plasters for exterior application
Ručková, Jana ; Opravil, Tomáš (referee) ; Šoukal, František (advisor)
This thesis is dealing with preparation of exterior thin-layer geopolymer plaster where the effect of supplement of various types of superplasticizers in their different amounts on the quality of geopolymer plaster is studied. The objective of this work is to determine suitable type of superplasticizer which would improve rheological quality of fresh plaster mix, its adhesion to the surface and last but not least would preserve good mechanical qualities of geopolymer binder. In the experimental part initially test subject were prepared from meta-kaolin, water, water-glass, sand and with supplement of various types of superplasticizers in various amounts. These test subjects were tested for compressive and flexural strength. Further workability and adhesion to the surface of these plaster pastes was observed. Geopolymer pastes were also subjected to calorimetric comparison of kinetic processes occurring during solidification and hardening. In order to identify the exact composition of superplasticizers used as rheological modifiers, the infra-red spectrometry of these substances was performed. There was a need to specify the water-glass in more detail as well, elemental analysis was performed on it on radiographic fluorescent spectrometry. To closer identify the structure and distribution of superplasticizer in geopolymer paste the pictures of the mix which was the most suitable for use for exterior thin-layer geopolymer plasters were made on scanning electron microscope. On the same mix radiographic diffraction on the powder samples was also performed which served for phase analysis.
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Research of interface between quartz and non quartz mould materials grains and geopolymer binder
Skřivánková, Vendula ; Burian,, Alois (referee) ; Cupák, Petr (advisor)
Presented thesis deals with monitoring of the properties of the interface between opening materials and geopolymer binder using three quartz and four non quartz opening materials. There is observed mainly the type of destruction of connective bridges. The theoretical part of the thesis briefly summarizes commonly used methods in foundries and monitors experience with implementation of geopolymers in different foundries. The practical part monitors shape of the grains of the chosen opening materials. There are writed down the results from the measurement of the bending strength and workability and there is observed the type of destruction of connective bridges.
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Modification of concrete elements for cooling towers
Mohelská, Lucie ; Šoukal, František (referee) ; Opravil, Tomáš (advisor)
This master´s thesis deals with the suppression of the growing of algae in cooling towers. Subject of the work is suggestion and testing surface modification of the existing mature concrete in order to suppress the growth of algae. In the frame surface modification, several commercially available and newly developed systems were tested. Testing systems are based on the basis of portland cement, geopolymers or formation of insoluble complex compounds containing metal elements (Zn, Cu). Experimental methods were applied in the real environment of cooling towers of Dukovany Nuclear power plant.
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