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Methodology for determining the provenance of raw materials for the production of historical lime mortars
Martinec, Petr ; Ščučka, Jiří
The methodology was developed in the years 2018-2021 as part of the solution of the project Historical landscape on the border of Silesia and Moravia financed by the Ministry of Culture of the Czech Republic (project No. DG18P02OVV017, NAKI II programme). The methodology is based on the long-term experience of prof. Petr Martinec, Ph.D. and Jiří Ščučka, Ph.D. in the field of geomaterial and building material analyses, which are carried out at the Institute of Geonics of the Academy of Sciences of the Czech Republic in cooperation with experts from the fields of archaeology and monument care. The methodology includes a comprehensive procedure for identifying potential original sources of raw materials used for the production of the main material components of historical lime mortars – aggregate and binder. The methodology also includes: principles of sampling mortars and comparative rocks or soils in situ, procedures for laboratory material analysis of aggregates, binders and rocks to determine relevant comparative parameters, and the main information sources that can be used when searching for sources of raw materials.\n
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New possibilities of using secondary raw materials for the renewal of the railway substructure
Buřičová, Karolína ; Luňáček,, Martin (referee) ; Drochytka, Rostislav (advisor)
The work is devoted to new possibilities for the recovery of secondary raw materials and track bed waste with a combination of both suitable and unsuitable soils. The aim of the thesis is to develop a new functional sample suitable for the recovery of a substructure of railways based on secondary raw materials. The theoretical part addresses the issue of the use of soil and secondary raw materials as the base layers of railway structures, and is focused on the possibilities of soil adjustments or enhancement. The practical part is focused on the analysis and selection of potentially suitable raw materials, the design of new raw material mixtures containing concrete recyclables, waste from cleaning the auto mixer and waste from cleaning the rail bed. Further, to modify the mixtures designed with fluid ash from biomass combustion to achieve higher toughness. Then they will be experimentally verified and based on the results the optimal formula for use in the solid of the railway bottom will be determined. Final optimal recipe achieving basic required parameters for use in active zone without the requirement for frost resistance and ecology is composed of 30 % of F4-CS, 4 % of portland cement CEM II-B/LL, 3 % of lime hydrate, 70 % of recycled concrete and 10 % of fluid ash from biomass combustion.
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Stabilization of the base layers of roads by using secondary raw materials
Buřičová, Karolína ; Kulísek, Karel (referee) ; Drochytka, Rostislav (advisor)
The bachelor's thesis deals with the up-to-date subject of secondary raw material usage. The aim of this thesis is to suggest a potential way of these materials’ usage by stabilization of base courses of road or railway constructions. Parameters of individual primary and secondary commodities are evaluated and the acquired knowledge in the field of stabilization is presented. An optimal technology for stabilization is suggested and applicability of used materials and their subsequently prepared mixtures is experimentally verified in the experimental work of this thesis.
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Study of the influence of the dielectrics on the optoelectronic properties of electroluminescent devices
Foldynová, Klára ; Novák, Vítězslav (referee) ; Vala, Martin (advisor)
This diploma thesis is studing the possibilities of influencing the optoelectric properties of printed light emitting panels, which work on the principle of electroluminescence excited by alternating electric field. The aim of this worrk is to monitor the influence od dielectric properties of electroluminescent phosphor binder on the targeted electroluminescence. In the theoretical part of this thesis, there are described principles of electroluminescence, suitable materials methods of characterization and preparation of panels using printing techniques. Experiment part contains electrical characterization of selected binders to determine their dielectric constants. Subsequently, printing pastes were formulated in different weight ratios of binder electroluminescent phosphor and model light-emitting panels were prepared. Optoelectric characterization was used to determine the change in irradiance. It was found that the dielectric properties of the binder significantly affect the resulting irradinace. It has same irradiance for a smaller amount od phosphor than with the binder with a low dielectric constant. The finding of this work can be used to improve the luminosity at the electroluminescent panels.
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Material properties research for use in high-temperature solar thermal storage tank
Šot, František ; Vala, Jiří (referee) ; TROJAN,, Karel (referee) ; Steuer,, Radek (referee) ; Šťastník, Stanislav (advisor)
The use of thermal storage energy, using phase change materials appears to be an effective way to store thermal energy storage with the benefits of the high amount of energy while maintaining isothermal nature of the process. PCM methods are used in latent thermal storage systems for heat pumps, as well as in solar engineering or for temperature control in spacecraft. The past decade has extended these principles for cooling and heating in the building. There are a number of PCM systems, which operate over a wide temperature range, are used in various applications. This document includes a brief overview of the development and analysis of available thermal storage working mainly on the principle of PCM.
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Evaluation of local filler sources suitability for anhydrite-based screeds
Šikral, Martin ; Kaláb, Michal (referee) ; Drochytka, Rostislav (advisor)
Goal of this thesis is to evaluate suitability of local filler sources for anhydrite based screed floor covers. The theoretical part is mostly aimed at summarization of general findings about flooring constructions and about anhydrite itself. The thesis also includes description of primary and secondary raw materials. The goal of this work is to suggest suitable fillers for anhydrite based screed floor covers in accordance with distance from Sika CZ, s.r.o with residence in Brno – Modrice. At the same time this thesis explores possibility of secondary raw materials usage as a replacement of primary fillers. In conclusion the thesis focuses on the laboratory test of chosen fillers, summarization and discussion of discovered findings.
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Development of ceramic shell for manufacturing of large Al investment castings
Hýbal, Ondřej ; Šmatelka, Jakub (referee) ; Horáček, Milan (advisor)
This diploma thesis deals with the choice of the most suitable composition of a ceramic shell mold for aluminum castings made by investment casting technology. The most suitable composition of the ceramic shells is chosen based on the results of the tests and from economic point of view. This thesis also deals with evaluation of the current conditions of the production of ceramic shells in Alucast, s.r.o and recommendations for stabilizing the process of manufacturing ceramic shell molds.
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