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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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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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Prevention of dental tissue loss by composite restoration repairs. Long-term durabillity of composite to composite bond in various environments.
Comba, Lukáš ; Bradna, Pavel (advisor) ; Veverka, Jan (referee) ; Roubalíková, Lenka (referee)
in english Introduction: Composite restorations in the oral cavity are exposed to an aggressive environment and mechanical challenge that gradually impairs their physical and mechanical properties. This may result in an enhanced wear rate, loss of esthetic properties and an increased risk of a restoration fracture or its marginal failure with a negative impact on the restoration's durability. Worn or failed restorations are usually completely replaced, which increases the irreversible loss of dental hard tissues. Repair of composite restorations by their partial replacement is therefore a minimally invasive, preventive and less time-consuming alternative to their complete replacement and increases their longevity. In the oral cavity, the adhesive bond between the existing composite restoration and the repair composite resin is exposed to various chemical substances and mechanical stress, e.g. surfactants in toothpastes, which can initiate its degradation. By decreasing the surface tension, the penetration of water into the adhesive joint can be enhanced, accelerating the hydrolysis of the adhesive and reducing the composite repair strength. The major and not yet fully resolved issue of composite repairs is how to achieve a strong and durable bond between the existing and repair composite materials....
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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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