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SCC with secondary raw materials
Ťažká, Lucia ; Ťažký, Tomáš (referee) ; Hela, Rudolf (advisor)
Bachelor thesis is focused on the possibility of using secondary raw materials and their application to the production of SCC. Large part deals with impurities of type I and its application results mainly from abroad. Furthermore, this work examines the impact of different types of impurities on the resulting concrete durability in various aggressive environments. The practical part is focused on the use of chemically non-reactive additives of type I instead of the commonly used additives of type II which are used to replace part of cement and the resulting design and manufacture of low-strength SCC using appropriate additives.
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Development of cement-bonded particleboards with modified matrix composition
Konečný, Dalibor ; Vacula, Miroslav (referee) ; Bydžovský, Jiří (advisor)
In manufacture of cement-bonded particle boards are in present-days used exclusively wooden particles as filler. This thesis deals with a research of possible substitution of this material, especially of waste emerging by production of CBPB itself. At first is completed a survey of possible substitute fillers and czech and foreign literature, dealing with issues of modification of composition of cement-bonded particle boards. In practical part are tested some treatments of waste and its adding to recipe. Further are analysed the influences of substitution of cement by slag and substitution of wooden particles by recycled fibreglass. By laboratory work with CBPB is monitored the influence of amounts of added wather to fresh mixture and also to properties of finished elements.
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Development of masonry systeme for simple construction of internal masonry structures
Lidmilová, Klára ; Dobiáš,, Jiří (referee) ; Zach, Jiří (advisor)
The diploma thesis deals with the development of a new masonry system, for the production of which recycled brick could be used as a secondary raw material. In the field of literary research, the work deals with the methods of construction of vertical structures, the possibilities of lightening concrete, the life cycle of building materials and the use of secondary raw materials in construction. In the practical part, a masonry system was designed based on market research in the field of internal non-load-bearing masonry structures and requirements for these structures. In order to achieve these properties, concrete was chosen as the material for its production, where recycled brick was used as an alternative aggregate. As it is supposed to be a system for precise masonry, the material was compacted by vibrocompression. At the beginning, recipes were designed to verify the basic properties of concrete: density of hardened concrete, compressive strength and tensile bending strength, then other properties such as thermal conductivity and sound absorption coefficient were tested on improved recipes. Lightening and dimensional modules have been modified to achieve optimal properties. This was followed by a proposal for the method of masonry and surface treatment of a wall. Finally, the economic and environmental aspects of the masonry system were evaluated.
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Effect of fly ash on the durability of concrete
Vašek, Tomáš ; Kulísek, Karel (referee) ; Hela, Rudolf (advisor)
Bachelor thesis consists of two parts, theoretical and practical. In the theoretical section provides basic information on the manufacture of fly ash, development and principle of High Volume Fly Ash Concrete and view on this type of concrete in the Czech Republic. Listed below are the world´s knowledge of conduct of durability and potential problems that can act on them. The theoretical part ends with summary of the utilization of fly ash in various areas of construction industry. In the practical part compares the characteristics of each recipe containing fly ash with recipe containing only Portland cement. Finally, is evaluation of results of practical part and influence on the durability of fly ash concrete.
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Secondary raw materials production from municipal waste
Kouřil, Čeněk ; Gregor, Jiří (referee) ; Kropáč, Jiří (advisor)
The main purpose of the bachelor thesis is to give an overview of the current system of municipal waste management and to demonstrate its techno-economical demands. To solve these objectives, an analysis of the current state in Czech Republic was carried out and a calculation tool was created to evaluate the overall techno-economical balance of the management system at the regional level. The results of the tool showed that it is expensive for municipalities to carry out waste management activities and would not be feasible without complex subsidies. The reader gets a basic overview of the current waste management system in Czech Republic and acquires knowledge of its partial techno-economical costs.
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Effective proposal and operation of recycling line as an element in waste management
Dufka, Martin ; Janošťák, František (referee) ; Gregor, Jiří (advisor)
This master thesis deals with the current situation of waste management of material usable municipal waste with focus on various fractions of plastics. The theoretical part summarises the legislation of waste treatment, also contains an analysis of the current situation of waste management in the Czech Republic and comparison the situation in the European Union. In the next part of thesis are described basic fractions of plastics and their properties. There are mentioned the current problems with plastics processing and the risks of leakage to the environment. Furthermore, a complex chain of plastic waste reprocessing is described, since the inception of plastics waste to the manufacture of products made from recycled plastics. The most attention is paid to the discription of recycling plant, where the output material from sorting lines is reprocessed into a secondary material in the form of flakes or granules. Also this part is focused on the technology of recycling line and the individual devices are described. In the practical part of the thesis is created techno-economic model of recycling line with the aim of its use for balance calculations of recycling and also economic evaluation. As a part of the model was made a market research of secondary raw materials with a focus on price development. Subsequetly, sensitivity analyzes of selected parameters are applied to the model and the impact of scenarios on the economic results are evaluated.
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Verification of different types of fly ash for production of artificial aggregate
Zahálka, Milan ; Donát, Pavel (referee) ; Drochytka, Rostislav (advisor)
Diploma thesis gives an overview of artificial lightweight aggregates based on fly ash. Fly ash such as the residues of coal burning is currently one of the most used secondary raw materials for new building materials for research papers. The results shows that the secondary energy products are not just fully substitute the primary component, but in many cases improves the final properties of building products. Wide complex of fly ashes not only from domestic sources was tested and it`s main properties important for it`s further application was determined. Laboratory production of artificial aggregates based on fly ash made by sintering and also by cold bonding and following manufacture of artificial fly ash aggregates in technological conditions are also solved. The thesis is simultaneously concentrate on review of the suitability of fly ash aggregates in lightweight concrete.It was found that the highest quality fly ash for the production of sintered fly ash aggregate is fly ash and FBC ash is the best for the production of cold bonded aggregates. It was also verified that both types of aggregates are applicable to lightweight concrete class LC 20/22. The vast majority of manufactured aggregates is suitable for the production of lightweight concrete class LC 30/33. It was demonstrated that the sintered fly ash aggregates can be also used for high strength lightweight concrete class LC 50/55. Tests have also verified that all tested fly ashes and products produced from them meet the requirements of legislation on environment.
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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 grout joint for chemical exposure using secondary raw materials
Matušková, Veronika ; Hodná, Jana (referee) ; Drochytka, Rostislav (advisor)
The aim of the bachelor’s thesis is the design of a high-quality polymeric grout joint using secondary raw materials and hazardous waste for increased chemical exposure. The main use assumed of the proposed grout joint is grouting of the cast basalt elements in building objects that are systematically exposure due to the highly aggressive chemical load. The use of input materials produced by progressive technologies should be another benefit of this grout joint to enhance the ecological aspects of the grout joint production.
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Electrically conductive composites based on secondary raw materials
Baránek, Šimon ; Šteffan,, Pavel (referee) ; Černý, Vít (advisor)
Electroconductive composites are modern materials that are commonly used in many industries such as the construction industry among others. For example these materials can be useful as sensors for monitoring changes in constructions. The aim of this thesis is the research of electrically conductive silicate composite based on secondary raw materials. The design of this composite is based on the development of its own mixtures and experimental verification of the effect of the structure. The introduction part consists of a detailed analysis of 15 materials. Samples of the 5 fine and 2 coarse electrically conductive fillers were tested. Composite with filler Condufit C4 was selected as representative for type of fine fillers. Composite with filler Supragraphite C300 was selected as representative for type of coarse fillers. The selection of the composites was based on the impedance of the fabricated composites with these fillers. Subsequently, the individual components of the primary mixture were substituted. The cement was replaced by high-temperature fly ash in the amount of 20, 30, and 40 %, the aggregate of a similar fraction was replaced by steel sawdust, and the primary electrically conductive fillers were replaced by secondary ones in the amount of 30 and 50 %. All proposed replacements reduced the impedance of the composite. The most effective replacement for impedance reduction was replacement with waste graphite (up to 92 % reduction), which also slightly improved the mechanical properties of the composite. The result of this thesis is an optimized electrically conductive composite based on secondary raw materials with a fine type of filler with 30 % replacement by waste graphite "odpad vysavač"which achieves an impedance of 5 ohms. The partial goal of this thesis is a verification of the influence of moisture on the impedance of composites. Results are significantly affected by moisture when using the coarse type of filler, when using the fine type are not.
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