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Effect of Grain Size of Waste Glass on Properties of Alkali Activated Aluminosilicate Composites
Novák, Václav ; Vyšvařil, Martin (referee) ; Bayer, Patrik (advisor)
The diploma thesis is focused on the use of the waste glass with different fineness on alkali - activated composites, mainly based on slag and fly ash. The theoretical part is focused on materials that are most used for alkaline activation - slag, fly ash and their composites with waste glass. The theoretical part also deals with the alkaline activation of composites from these materials and the factors that influences the microstructure and properties of these composites. In the experimental part were prepared composites from slag and fly ash with a waste glass as substitute. These composites then have been examined on mechanical properties and microstructure, also how different fineness of glass influences these properties. Then it will be decided whether it is economically advantageous grinding waste glass to finer fractions
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The development of composites based on alkali-activated matrices resistant to extreme temperatures
Ševčík, Marek ; Šácha, Libor (referee) ; Dufka, Amos (advisor)
The diploma thesis is focused on the development of composites from alkali activated materials (AAM) and their resistance to extreme temperatures. The theoretical part describes alkaline activation and precursors for the production of AAM. Furthermore, the problem of the effect of extreme temperatures on these materials is described. In the experimental part, the optimal silicate modulus with respect to the properties of AAM was gradually determined, and the effect of extreme temperatures on the AAM matrix was verified. In the next stage, the effect of the filler with respect to the behavior at extreme temperatures was tested and then the final formulation was optimized.
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Cleaning effect of unconventional filtration materials
Fialová, Tereza ; Hynánková,, Eva (referee) ; Kriška-Dunajský, Michal (advisor)
Constructed wetlands and the soil filters are water treatment devices using the filter material that in most cases consists of natural river gravel, coarse sand or crushed stone. Master´s thesis deals with the research of cleaning effect of unconventional filtration materials, or more precisely with examination to load real waste water in a filtration column, to prove their ability to be used as an alternative medium that can ensure better cleaning effect. For the research work following metallurgical industry materials were used: fine slag and coarse slag 8-16 mm, materials from the natural character: zeolite, keramzit, a plastic material: PUR-foam. Also the traditional materials of fine gravel and coarse gravel were tested to compare the cleaning efficiency. Both the hydraulic and the cleaning efficiency of all above mentioned materials were tested. The examined hydraulic parameters are particularly porosity, hydraulic conductivity and suspended solids, turbidity and oxidation-reduction potential of both the inflow and outflow of the filter columns were determined. Accredited laboratory set the inflow and outflow of the filter columns BOD5, CODCr, total phosphorus, total nitrogen, nitrite, nitrate, ammonia and dissolved oxygen. By evaluating the results of the measurements it is determined which materials are suitable to be applied in the constructed wetlands and the soil filters. This filtration column was modeled by program HYDRUS and the result was compared with real results.
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Study of the effect of selected types of aditives on the properties of cement composites
Kavka, Lukáš ; Ťažký, Tomáš (referee) ; Bodnárová, Lenka (advisor)
The diploma thesis describes admixtures for concrete. It deals with the influence of admixtures on the properties of cement composites in the fresh and hardened state. The theoretical part described the individual components of concrete, where the main attention was focused to inert admixtures and their effect on mechanical properties, shrinkage, resistance of cement composites to aggressive medium. Furthermore, the effect of admixtures on concretes with recycled aggregates was described. In the first stage of the practical part, cement mortars with 25, 35 and 50% replacement of cement admixtures were created. In the second stage, concretes with admixtures and a minimum strength class of C30/37 and C50/60 were created. Finely ground granulated slag, micronized limestone and granite stone dust were used as admixtures in mortars and concretes. The change of properties in the fresh and hardened state was observed on cement composites.
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Blended alkali-activated aluminosilicate binders
Mizerová, Cecílie ; Bayer, Patrik (referee) ; Rovnaník, Pavel (advisor)
The first part of the work presents a summary of the current knowledge of two-component blended alkali-activated binders based on blast furnace slag, fly ash, metakaolin and ground brick with emphasis on their workability, microstructure, mechanical properties and durability. In the experimental part the alkali-activated binders with different ratio of fly ash and metakaolin were made to compare their workability and mechanical properties. The binder structure was evaluated by means of scanning electron microscopy (SEM) and mercury intrusion porosimetry. From the literature review and my own achievements it can be concluded that the combination of single precursors has a positive effect on the majority of the assessed properties of the material.
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Possibilities of using different types of admixtures in shotcrete technology
Berčík, Martin ; Brožovský, Jiří (referee) ; Hubáček, Adam (advisor)
The Bachelor’s thesis is conceived in the form of research findings on current knowledge of inert and active ingredients and their effects on the shotcrete. It focuses mainly on the composition of individual ingredients, their function executing in the concrete mix and explains how they affect the selected physical and mechanical properties. The work enlightes the importance of using co-products from the industry production as an additive to concrete in terms of both ecological and partly economical.
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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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Rehydration of alkali-activated slag after high temperature loading
Fialová, Barbora ; Bayer, Patrik (referee) ; Rovnaník, Pavel (advisor)
Ground granulated blast furnace slag is a by-product of the steel industry and is often used in combination with ordinary Portland cement as a binder in concrete. When concrete is exposed to high temperatures, physical and chemical transformations lead to significant loss of mechanical properties. This study aims to investigate the effect of high temperatures and rehydration on the mechanical properties, microstructure and phase composition of alkali activated slag. The results of the research could make an important contribution to decisions made concerning the reconstruction of structures affected by fire. In suitable cases it would be possible to regenerate parts of a structure instead of totally rebuilding it.
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