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New lightweight floors with secondary raw materials
Tůmová, Eva ; Bydžovský, Jiří (referee) ; Ďurica,, Tibor (referee) ; Kolář,, Karel (referee) ; Drochytka, Rostislav (advisor)
The thesis deals with the development of new type of lightweight floors based on secondary raw materials. In the introduction, the current knowledge in the field of lightweight building materials, especially screeds and lightweight porous concrete, is presented. The thesis describes brief history of production of aerated concrete and its development up to the present. Further, the thesis describes the procedure of design and testing of new lightweight materials for use in floors. The proposed recipe has been thoroughly tested and the best combination of components for use in lightweight porous concrete floor screed has been selected. The thesis also examines the microstructure of the material being developed. The main result of the dissertation is the developed product, which is already used in practice and is produced and sold on the market as part of the system of lightweight building materials.
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Proposition of grounding enhancing cement composite mixture
Sochor, David ; Bydžovský, Jiří (referee) ; Drochytka, Rostislav (advisor)
The bachelor thesis deals with the design of a conductive cement composite grounding mixture for protection of building structures in areas with low conductivity. The theoretical part is mainly focused on summarizing the knowledge of the current protection of buildings against lightning and overvoltage. The study includes knowledge in the field of conductive building materials and aims to present the design of a cement composite mixture to improve grounding. Choosing the right raw materials to achieve electrical conductivity. A maintenance-free material has been developed, no humidity needed material while maintaining conductivity. The work it examines the possibilities of using industrial wastes as secondary raw materials. The conclusion focuses on laboratory testing of newly developed materials, summary and discussion of the results. With the developed samples, the resistivity was greatly reduced. The positive effect of ferric dust and carbon particles has been demonstrated.
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Ash – the raw material base for the future
Marko, Michal ; Ptáček, Petr (referee) ; Opravil, Tomáš (advisor)
This master’s thesis responds to the worldwide problem concerning in the search of new material base for the future usage. Solid residues from high temperature or fluid coal combustion could be one of many alternatives to the raw materials. The study deals with the analysis of side energy products produced by power plant industry in the Czech Republic. Based on the fly ash chemical composition, possibilities of aluminium and even iron and titanium separation were proposed and then proved in the laboratory scale. Extracted components were separated selectively using apropriate methods. Then a couple of sintering reactions leading to improvement the leachability of selected elements from the fly ash matrix were carried out. Appropriate input material modification by high-temperature sintering reaction combined with extraction process in the sulfuric acid solution leads in dissolution up to 99 % of aluminium from the fluid and high-temperature fly ash.
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Study of microstructure of autoclaved aerated concrete with using of secondary raw materials
Martanová, Jana ; Suchý, Peter (referee) ; Kulísek, Karel (advisor)
Autoclaved aerated concrete is a used building material, especially for its thermal insulating properties. During autoclaving, an aerated concrete microstructure produces crystalline CSH phases, primarily tobermorite. The ingoing substances are calcium oxide and silica. In addition to commonly used raw materials, secondary raw materials rich in silicon dioxide can be used for production. The use of secondary raw materials gives the opportunity for the construction industry to be more environmentally friendly. Another benefit is the reduction of financial costs. The work explores the influence of individual secondary raw materials on the microstructure. High-temperature fly ash, fluid fly ash, cinder, ground glass and zeolite were used The raw materials were mixed with unalloyed lime at a molar ratio of calcium oxide to silicon dioxide of 0.73 and 1.0. Autoclaving capsules were used to synthesize tobermorite under laboratory conditions. Autoclave was performed at 170 °C and 190 °C with hydrothermal durations of 4, 8 and 16 hours. The most important influence on the microstructure was high-temperature fly ash, on the contrary, the greatest influence on the mechanical properties is attributed to the ground glass.
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Development of new technology of sand autoclaved aerated concrete with using of secondary raw materials
Ondříčková, Pavlína ; Suchý, Peter (referee) ; Drochytka, Rostislav (advisor)
Autoclaved sand aerated concrete is a modern building material with high thermal insulation properties. Only sand is used as the primary silicate component of aerated concrete in the Czech Republic. For the more favourable economic and ecological properties of aerated concrete, the use of secondary raw materials is used in this work. The secondary raw materials examined included fluidized bed and fly ash, slag and glass recycled. The aerated concrete composite with secondary admixtures was developed under hydrothermal conditions of a laboratory autoclave for 7 and 12 hours at 190°C. From the secondary raw materials tested, a 10% glass recycler additive yielded the highest strength. Other additives that have a positive effect on mechanical properties include SAKO and Oslavany. From the results of the work it is evident that the use of secondary raw materials increases the strength, improves the rheology of the mixture and supports the formation of tobermorite.
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Development of industrial adhesive material for deposition of nonabsorbent components
Bergerová, Kamila ; Černý, Vít (referee) ; Drochytka, Rostislav (advisor)
The thesis deals with the development of industrial adhesive material for deposition of nonabsorbent components in environments exposed to aggressive chemicals and high temperatures. The theoretical part is mainly focused on summarizing knowledge about adhesive materials. The study also includes description of bonded components, describes theory of adhesion and introduces the used materials. The primary aim of this work is to present new design of material composition of a new adhesive of polymer and silicate base material. The work also investigates the possibility of using the industrial waste in the form of secondary raw material. The final part is dedicated to laboratory testing of new developed materials, summarization and discussion of the obtained results.
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The Use of Alternative Sources in the Building Industry
Dvořák, Jakub ; Vymazal, Tomáš (referee) ; Žižková, Nikol (advisor)
This bachelor thesis is focused on the use of waste as alternative raw materials in construction industry. The first part is dedicated to the historical development of waste management, to the valid legislation in the Czech Republic in 2017 and outlines the distribution of waste according to various criteria. The information about waste production and waste management is processed in the form of tables and graphs. The more extensive second part of the thesis uses theoretical knowledge in the field of waste management and on the base of the Waste Separation Catalog is composed a list of waste materials which can be used in construction industry. Further are described the possibilities of suitable waste utilization at production and also mentioned some particular construction products with their features.
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Application of renewable and recyclable raw materials for preparation of new polymers
Horák, Pavel
This thesis deals with optimalization of flexible polyurethane foam recycling with using of natural polyols based on rape seed oil and fish oil and it explores applications of depolymerized polyol product by formulations of new polyurethane materials. The experiments of depolymerisation showed that both tested natural oil (rape seed oil and fish oil) can be used as effective reagents for polyurethane recycling. Reaction conditions of depolymerisation were optimised with model flexible polyurethane foam and applied on waste foam from real conditions. Gain of depolymerisation is one-faze low viscosity (to 1500 mPa.s) liquid polyol products with content of hydroxyl groups ca 3 mmol/g. These polyols can be used for polymerisation of new materials. First application of recycled polyols was formulation of polyurethane foam systems. Through optimising of formula was prepared low-density semirigid foam containing 100 percentage of recycled polyol. Properties of these foams correspond to commercial foams. To prepare of homogenous cast polyurethane system based on recycled polyols it was necessary to add proper solvent, therefor extent of application has been lowered. On that account the systems were tested for study of polyaddition reaction and for following properties of the material. In these tests, the reactivity...
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