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Assessment of resistance castables to chemically aggressive environments.
Mátl, Daniel ; Henek,, Milan (referee) ; Nevřivová, Lenka (advisor)
There are applications of refractory concretes for places where these are exposed to corrosive environments. This bachelor thesis deals with both description the corrosive effects and methodology of their testing. One of the most important properties of materials, affecting the chemical corrosion resistance, is their density. The practical part of the thesis is focused on testing the grogs which are currently used for production of refractory concrete. The aggregates were tested for the resistance to sulfuric acid.
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Mechanical and Chemical Surface Endurance of polymers materials, testing and posibilities fro improvements
Vaníček, Štěpán ; Seidlová, Michaela (referee) ; Petránek, Vít (advisor)
Mechanical and chemical resistant multilayer polymeric floors are the most important characteristics of classification in the evaluation of surface and texture. Mentioned as organic binders which are used for the realization of the matrix. Further discussion on how to get fillers forming the supporting folder. Created a summary of the key test of mechanical and chemical characteristics according to current standards. The theoretical part is concluded with a reflection on the possibilities of improving the surface resistance of synthetic floors. The practical part was focused on testing the strength, resistance to impact and adhesion to the base layer. Finally, the overall evaluation of the test results in accordance with the theoretical part.
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The development of composites based on inorganic binders designed for the extreme applications
Janoušek, Petr ; Šácha, Libor (referee) ; Dufka, Amos (advisor)
The topic of this master's thesis is the development of composite materials based on inorganic binders for use in extreme conditions. It means especially geopolymeric or alkali activated materials (AAM) based composites. The theoretical part of this thesis summarizes knowledges about the development and use of alkali-activated materials, their structure and mechanisms of their formation. It also deals with the applicable raw materials for AAM and their exciters, which are in particular water glass and sodium hydroxide. There also have been a summary of the effects of high temperatures and chemicals on the mechanical properties of AAM and the requirements of standard EN 1504-3 for repairing materials. The task of the practical part was to develop a repair mortar for concrete structures based on AAM so that its production was as simple as possible, ie one-component materials. Gradually six recipes have been develeoped. Test specimens made from these recipes have been putted to selected tests according to the requirements of ČSN EN 1504-3.
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Development of new chemically resistant coating system containing secondary raw materials
Stodolovská, Šárka ; Jakubík, Aleš (referee) ; Drochytka, Rostislav (advisor)
New types of highly chemically resistant coating systems, primarily designed for concrete and metal substrates are designed and experimentally verified within the diploma thesis. Secondary raw materials, including solidified hazardous waste, are used as microfillers. The developed coating system is solved in two quality levels – PREMIUM and ECOLOGY. The level of PREMIUM is mainly designed for environments where extreme chemical stress is occurring. The polymer coating systém ECOLOGY can be used in environments where aggressive chemical media also act, however the ecological foot of the input raw materials is most important. The diploma thesis is dealing with current issues in the practice and it is the part of the research project.
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SPECIAL POLYMER COATINGS AND SCREEDS MATERIALS WITH USE OF SECONDARY RAW MATERIALS
Žlebek, Tomáš ; Seidlová, Michaela (referee) ; Bydžovský, Jiří (referee) ; Ďurica, Tibor (referee) ; Drochytka, Rostislav (advisor)
The work deals with the development of new polymeric coatings and screeds – epoxy, polyurethane and vinyl ester materials with the use of hazardous waste in the form of fillers. The areas that are destined for their landfill are constantly expanding and the costs of disposing of this waste are high. Their use eliminates negative impacts on the environment, but also leads to significant financial savings. The aim of this PhD thesis was to find a suitable way to treat selected hazardous waste and experimentally verify the possibilities of using the fillers pre-treated by optimal way in polymer coatings and screeds. The coatings and screeds are intended primarily for concrete substrates but the possibility of use on metal substrates, asphalt and cement-bonded particle boards was also been verified. These materials serve as a secondary protection of structures against the adverse effects of weather conditions. Secondary raw materials were used as fillers, which were fluidized bed combustion fly ash contaminated due to flue gas denitrification and specially pre-treated hazardous waste (solidification products). The aim was to proceed progressive use of the secondary raw materials as much as possible in order to reduce landfilling in the maximum possible way. It was necessary to treat hazardous waste in such a way that the most effective solidification would be achieved. The behavior of the solidifaction products in the polymer matrix, the distribution of particles in the structure and the disruption of coatings and screeds due to chemical stress were also investigated.
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Development of a New Repair Mortar Using Secondary Raw Materials
Figala, Petr
This paper deals with the research of a new repair mortar modified with secondary raw materials. The aim of the work is to develop a material characterized by chemical resistance suitable for the rehabilitation of sewer concrete structures. Resistance to aggressive sulphate solution and to attack by sulfuric acid was chosen as the key parameters for the choose of a final mixture. Chemical resistance was tested by simulating the exposure environment in laboratory conditions, according to the methodology of DIN 19573. The obtained results show that by suitable modification of the reference mortar it is possible to maintain the values of physical-mechanical characteristics and improve the chemical resistance of test samples. The final mixture will be further tested in field conditions.
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Development of new chemically resistant coating system containing secondary raw materials
Stodolovská, Šárka ; Jakubík, Aleš (referee) ; Drochytka, Rostislav (advisor)
New types of highly chemically resistant coating systems, primarily designed for concrete and metal substrates are designed and experimentally verified within the diploma thesis. Secondary raw materials, including solidified hazardous waste, are used as microfillers. The developed coating system is solved in two quality levels – PREMIUM and ECOLOGY. The level of PREMIUM is mainly designed for environments where extreme chemical stress is occurring. The polymer coating systém ECOLOGY can be used in environments where aggressive chemical media also act, however the ecological foot of the input raw materials is most important. The diploma thesis is dealing with current issues in the practice and it is the part of the research project.
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Design of vapor proof protective coating for concrete with chemical resistance
Fousková, Marika ; Hodná, Jana (referee) ; Drochytka, Rostislav (advisor)
The main content of the bachelor's thesis is to design a vapor-tight chemically resistant coating using secondary raw materials. Coatings are applied primarily for the purpose of protecting concrete structures that are exposed to chemical stress. Secondary raw materials are used in the coating in the form of a microfiller, which is evenly dispersed in the polymer matrix. The proposed coatings show high adhesion to concrete, excellent workability and applicability, while the filler in the form of secondary raw materials does not impair the properties of the coating, both in fresh and polymerized state.
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Design of chemically resistant coatings using secondary raw materials and hazardous waste
Stodolovská, Šárka ; Jakubík, Aleš (referee) ; Drochytka, Rostislav (advisor)
On the basis of theoretical knowledge gained from Czech and foreign technical literature, two types of coatings using fillers based on secondary raw materials, including hazardous waste, is designed and experimentally verified. The expected use of the proposed coating systems, both PREMIUM and ECOLOGY, is the protection of building structures that are permanently stressed by increased chemical stress. When designing the PREMIUM coating material, emphasis is primarily focused on chemical resistance and functional parameters, and the ecological performance of the raw materials used is monitored primarily with the ECOLOGY coating material. In both cases, it is important to maintain a favorable price / value ratio.
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DEVELOPMENT OF SPECIAL REHABILITATION MATERIALS FOR CONCRETE FOR EXTREME STRESS WITH USE OF SECONDARY RAW MATERIALS
Hodul, Jakub ; Klečka,, Tomáš (referee) ; Ďurica,, Tibor (referee) ; Bydžovský, Jiří (referee) ; Drochytka, Rostislav (advisor)
The doctoral thesis deals with finding the use of some waste and secondary raw materials in the production of special polymer remediation materials for concrete, which could be applied even in constructions, where extreme mechanical and chemical load is occurred. The aim of this doctoral thesis is experimental examination of the possibility of using selected types of waste, including hazardous waste which represent the highest risk to environment, and secondary raw materials as a substitute for the currently used primary fillers in order to reduce the ecological footprint of the product itself. Some types of secondary raw materials, such as filter fly ash contaminated by flue gas denitrification process, are no longer used as a concrete admixture or partial cement substitution due to unwanted release of toxic ammonia (NH3). Mainly for this reason, the thesis deals with the progressive utilization of such types of secondary raw materials as well as with another currently unused waste into polymeric patching, grouting and anchoring materials while preserving or improving the final properties compared to reference materials using only primary raw materials. The result of this thesis is to find out suitable formulations for efficient preparation of special polymeric remediation materials for concrete containing waste and secondary raw materials as fillers. The partial aim of the thesis and a the scientific contribution is an observation of the developed materials internal structure using a modern device, CT tomography, an influence of the filler type on the long-term durability, and last but not least the observation of the rate of pollutants incorporation, found in hazardous waste, into the polymeric matric with the aid of EDX and FTIR analysis.
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