National Repository of Grey Literature 70 records found  1 - 10nextend  jump to record: Search took 0.00 seconds. 
Development of highly resistant composite using secondary raw materials and cast basalt
Černý, Pavel ; Jakubík, Aleš (referee) ; Drochytka, Rostislav (advisor)
The diploma thesis deals with development of high resistant composite, which brings its properties closer to the melted basalt products. This fact will allow substitution of basalt elements in hostile chemical environment by newly developed material and completes its product line. High resistant composite also consists of secondary raw material in highest possible amount. Material that is being evolved carries high strength, abrasion resistance and is also resistable in hostile chemical environment.
Development of chemically resistant sprayed mixture
Hermann, Radek ; Dohnálek,, Pavel (referee) ; Drochytka, Rostislav (advisor)
Production wastes for which a direct use in another production is found become secondary raw materials. There are several institutions in Czech Republic and in the world, which are currently dealing with the issue. This thesis deals with the issue of cementitious spray concrete mixtures and deals with the possibilities of using secondary raw materials and waste from production as partial replacement of binder and filler in these mixtures. The aim of this theses is to optimize the composition of additives in the recipe of the commercially produced pray mixture and to verify the influence of the degree of substitution of binder or filler by secondary raw materials on its physical-mechanical properties. The aim is to maintain or increase these properties while substituting the binder and filler as much as possible. After the evaluation of results, it is possible to say, by suitable optimization of the additives it is possible to achieve a significant improvement of the physical-mechanical properties of the mass and furthermore, from the results of this thesis follows, that by substitution of 100% fine filler in combination with substitution of 30% binder it is possible to maintain or increase the physical-mechanical properties after 28 days of curing and to significantly increase these properties after 90 days of curing. The results of this thesis are also related to the reduction of economic impact on production of the spray mixture, mainly due to the use of secondary raw materials.
Development of adhesive material for the installation of basalt elements on silicate foundations under severe exposure conditions
Bergerová, Kamila ; Jakubík, Aleš (referee) ; Drochytka, Rostislav (advisor)
The diploma thesis deals with research and subsequent development of a new adhesive material for the installation of nonabsorbent basalt elements on silicate foundations under severe exposure conditions. For commercially produced tile adhesives, only primary raw materials are used as fillers. The purpose of this work is to evaluate the possibility of utilization of secondary raw materials as fillers in the tile adhesive. The thesis is mainly focused on the durability of these materials after exposure to the aggressive environment.
Anchor silicate expansion material with increased temperature resistance
Müller, Jiří ; Luňáček,, Martin (referee) ; Drochytka, Rostislav (advisor)
This master thesis deals with the development of an expansive anchor material. This material is intended especially for the engineering and power industry where the operating conditions cause thermal stresses of the anchor. In order to meet the requirements for a firm and secure connection of the anchored part, it is necessary to achieve excellent physical-mechanical properties of the developed material such as high compressive strength, high tensile strength based on the base, and resistance to thermal stresses till 200 ° C. All of these processes must be achieved after the ageing of the cement material. Due to the current trend of modern materials that are environmentally friendly, the use of partial replacements for Portland cement is used as a substitute for a primary binder.
Possibilities of utilisation different types of fly ashes in the production of oxidized asphalt insulation strips
Sklenářová, Radka ; Sokol, Pavel (referee) ; Drochytka, Rostislav (advisor)
Reducing the impact of modern industrial production on the environment and reducing the waste generated is undoubtedly one of the most discussed topics of the present time. In the production of fossil-fueled electricity, a large amount of fine-grained waste fly ash is generated. The possible use of ash as secondary raw materials in the construction and building materials industry is one of the many environmental challenges that the energy industry is concerned with. The aim of this diploma thesis was to verify possibilities of utilization of different kinds of power station fly ash as filler in asphalt mixtures for the production of oxidized asphalt insulation strips. The main emphasis was put on the clarification of the influence of the properties of the different types of fly ashes on the resulting rheological behavior of the mixture of asphalt binder and power fly ash, which is professionally called mastic. Mastic forms a technology-critical insulating layer in the asphalt insulation strip. The prediction of the rheological properties and therefore the workability of mastic appears to be an essential element in the management of production, especially under the conditions of the variability of input raw materials. In order to solve the assigned task it was necessary to perform detailed analyzes of fly ash properties, to select the corresponding quantification variable for assessment of the mastic processability and to find the signal fly ash properties, which appears to be a control parameter of workability. As a suitable method for assessing the processability of mastic, a shear viscosity measurement method was chosen. On the basis of the findings, it is possible to state that the use of fly ash from the production of oxidized asphalt bands is not recommended as the mastic prepared from these fly ashes are unprocessed at the assumed concentrations. The negative effect of fly ash after denitrification on the mastic processability has not been demonstrated.
Development of high quality autoclaved aerated concrete using alternative resources
Kostura, Patrik ; Janovský, Radek (referee) ; Drochytka, Rostislav (advisor)
With the growing trend of construction, the demand for building materials is growing steadily. Porous concrete is widely used in the building industry, that makes efforts to discount production and simultaneously save the environment. The aim of this thesis is to develop high-quality porous concrete by using alternative raw materials as a substitute for silicate sand. As a possible substitute were chosen: Silica masonry, foundry sand and fireclay boulders. The influence of two key parameters - the specific surface (130, 240 and 350 m2·kg-1) and the amount of silica sand substitution (10, 30 and 50 %) were monitored. Two autoclaving modes (7 and 12 hours of isothermal durations at 190 ° C) were tested. Based on the physico-mechanical and mineralogical characteristics of the porous concrete composites was chosen the ideal surface area of 240 m2·kg-1 and time of isothermal endurance was determined at 7 hours (temperature 190 ° C, pressure 1,4 MPa). From the optimal intentions were created samples with a macroporous structure, using an aluminum powder. Physical-mechanical properties and microstructural analysis (XRD, SEM) were subsequently determined on the samples. Ideal recipes were proposed with 50% sand substitution of fireclay boulders and 10% substitution of foundry sand. This was due to a 10% higher compressive strenght and an increase of the coefficient of constructiveness, compared to the reference sample.
Crystallization of coating systems based on epoxy resins.
Vyhnánková, Michaela ; Dohnálek,, Pavel (referee) ; Petránek, Vít (referee) ; Drochytka, Rostislav (referee) ; Bydžovský, Jiří (advisor)
Crystallisation of epoxy resins based on bisphenol A and bisphenol F is the natural property of these oligomers. However, manufacturers of paints and other systems based on these epoxy resins, strive to slow down the crystallisation process as much as possible, thereby prolonging the shelf life and improving the competitiveness of their products. The main aim of the thesis is generalisation of the factors influencing the crystallisation process of epoxy resins based on bisphenol A and bisphenol F, verifying new approaches to the possibility of influencing the crystallisation process and determining the possibility of using a certain degree of epoxy resins crystallinity based on bisphenol A and bisphenol F in the preparation and production of epoxy resinbased coating systems.
Gel infusion screen system for additional waterproofing of various types of masonry with share of secondary raw materials
Melichar, Jindřich ; Klečka,, Tomáš (referee) ; Dohnálek,, Pavel (referee) ; Novotný, Miloslav (referee) ; Drochytka, Rostislav (advisor)
Virtually any construction project in our climate zone is facing some form of moisture. Older and historical buildings are mostly affected by the negative impact of water. Previously, the additional reduction of the moisture was executed only by mechanical methods, pushing insulating sheets or breaking through and cutting of masonry. Over time chemical methods were also invented, which are compared to the mechanical considerably simpler and user friendly applications to statics of treated buildings, making them ideal for the treatment of historical buildings or buildings that would not bear significant disruption. The main principle of chemical methods of redevelopment of wet masonry is the application of special material into the line of drilled holes with a given pitch. Subsequent penetration of the grouting material is believed to intersect an arc of individual drill holes, and thus to create so-called grout curtain that prevents the accumulation of water above it. Injection material may also contain a proportion of secondary raw materials, thereby reducing the influence of the impact of production on the environment. Efficiency infusion materials in masonry affected by many factors, such as temperature, humidity, or the type of material treated. It is also an important factor to determine the effectiveness of the remediation of the material, proving its ability to penetrate the building material by identifying its presence in it.
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.
Complete insulation system for high temperature using secondary raw materials
Mészárosová, Lenka ; Ďurica,, Tibor (referee) ; Kolář,, Karel (referee) ; Kulísek, Karel (referee) ; Drochytka, Rostislav (advisor)
This work deals with the development of new types of insulating materials for use in the higher temperature. The area of application of these insulation materials is especially industrial chimneys, where the exhaust gases achieves 85 to 200 °C, furthermore it is industrial boilers and furnaces with surface temperature to 500 °C. In the introduction is presented the current knowledge in the field of insulating materials in the Czech Republic and in the world. Then the work is dealing with proposal of possible raw materials and suitable formula. According to purpose of use is the work divided into two parts – high temperature insulation for simple and for complicated shapes conditions. The sub-sections are divided to different possibilities of performance. The aim was, based on the scientific expertise of other authors in the world, design a new insulation system and redound to deepening scientific knowledge in the area of lightweight materials on the silica basis and to the extension of the offer of new products in building and industrial practice.

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