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Floor systems based on secondary raw materials from power industry
Kalina, Martin ; Švec, Jiří (referee) ; Opravil, Tomáš (advisor)
This thesis deals with the possibility of using secondary raw materials from the energy industry especially the solid residues of high temperature combustion of coal. These materials should be now seen as a material with wide usage especially in the construction industry. One possibility of their usage is a replacement of binding parts in floor systems. The aim is to find the optimal composition of the mixture, which fits all the technical requirements and at the same time reduces the cost of its production. An advanced methods of powder X-ray diffraction analysis, particle size laser diffraction analysis and X-ray fluorescence analysis were used to determine the raw materials. Based on these analysis the experiments were designed focusing on the mechanical properties, the observation of the evolution of hydration’s heat in prepared mixtures and their time of setting and hardening.
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Utilization possibilities of industry gypsum and secondary materials containing for preparation of composites
Weiglová, Jana ; Šoukal, František (referee) ; Opravil, Tomáš (advisor)
The work studies the possibilities of the utilization of secondary raw materials produced by power industry. It addresses mainly the gypsum by-products and fluidized coal combustion ash. As for the secondary raw materials the content of sulphites is observed and the dependences of their transformation to sulphides via natural oxidation by air oxygen or by addition of adequate oxidant are studied. The work follows with describing the effect of sulphides contained in raw materials on the mechanical properties of composites prepared from several various matrices such as alumina or portland cement, lime or portland clinker. As for pure portland clinker the ability to retard the setting is also observed. The amount of contained sulphites is measured volumetrically via indirect titration of iodine surplus by sodium thiosulphate with the starch size as the indicator.
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Self-leveling floors based on secondary raw materials
Darakevová, Michaela ; Šiler, Pavel (referee) ; Opravil, Tomáš (advisor)
The work deals with the use of secondary raw materials in the self-leveling floor systems when used as a secondary raw material perform here especially classic ash, boiler slag and gypsum from flue gas. Work is looking for ways in as much as possible to replace conventional materials used in self-leveling flooring systems, secondary energy products. The aim of this work is to determine the optimal amount and ratio of secondary raw materials in self-leveling flooring compounds so that they are maintained or improved standard properties of these compounds reported in the standards. The work is divided into several points, the first point was first sought appropriate composite binder, where it was used as aggregates reach a standard sand. At other points the sand was then replaced by secondary materials. Were also tested ingredients to influence the rate of cooling, or for the onset of the initial strength.
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Possibilities of Cellular Concrete Utility Properties Improvement for Low-Energy Buildings
Neubauerová, Alena ; Ing.Oldřich Dobrý, CSc. (referee) ; Kulísek, Karel (advisor)
Aerated concrete is a modern construction material with excellent thermal – insulation properties with possibility of a fast construction of the building. Moreover we can use secondary raw materials such as fly ash and gypsum during production of aerated concrete, so we save our environment. At present we are trying to save funds for heating the house, so we are looking for suitables materials to cover the requirements for low energy housing. But low – energy buildings wouldn´t be enough for the future. It´s possible now to build passive houses and zero houses, that´s why advances are necessary in improvement of utility properties of building materials, aerated concrete in our case.
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Floor systems based on secondary raw materials from power industry
Kalina, Martin ; Švec, Jiří (referee) ; Opravil, Tomáš (advisor)
This thesis deals with the possibility of using secondary raw materials from the energy industry especially the solid residues of high temperature combustion of coal. These materials should be now seen as a material with wide usage especially in the construction industry. One possibility of their usage is a replacement of binding parts in floor systems. The aim is to find the optimal composition of the mixture, which fits all the technical requirements and at the same time reduces the cost of its production. An advanced methods of powder X-ray diffraction analysis, particle size laser diffraction analysis and X-ray fluorescence analysis were used to determine the raw materials. Based on these analysis the experiments were designed focusing on the mechanical properties, the observation of the evolution of hydration’s heat in prepared mixtures and their time of setting and hardening.
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The admixtures which are influencing setting time of portland cement
Hlaváček, Jaroslav ; Kalina, Lukáš (referee) ; Opravil, Tomáš (advisor)
During the production of concrete is important the careful selection of raw materials. Nowadays, we are trying in the production to minimize the economic burden and to maximize the use of secondary raw materials. This work is focused on the use of secondary raw materials from the energy industry in construction for the preparation of hydraulic binders. As the main raw materials were used different power plant fly ash from fluidized combustion. The composition of these secondary materials is quite different from conventional high-temperature ash, due to mixing with water they solidify and harden. Experiments were performed with three lodge fly ash from electrostatic precipitators of the fluidized combustion and one high-temperature fly ash. This work is focused on the possibility of monitoring the use of these secondary materials in construction, especially when tests were evaluated characteristics of strength and speed of setting and hardening.
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Utilization possibilities of industry gypsum and secondary materials containing for preparation of composites
Weiglová, Jana ; Šoukal, František (referee) ; Opravil, Tomáš (advisor)
The work studies the possibilities of the utilization of secondary raw materials produced by power industry. It addresses mainly the gypsum by-products and fluidized coal combustion ash. As for the secondary raw materials the content of sulphites is observed and the dependences of their transformation to sulphides via natural oxidation by air oxygen or by addition of adequate oxidant are studied. The work follows with describing the effect of sulphides contained in raw materials on the mechanical properties of composites prepared from several various matrices such as alumina or portland cement, lime or portland clinker. As for pure portland clinker the ability to retard the setting is also observed. The amount of contained sulphites is measured volumetrically via indirect titration of iodine surplus by sodium thiosulphate with the starch size as the indicator.
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Self-leveling floors based on secondary raw materials
Darakevová, Michaela ; Šiler, Pavel (referee) ; Opravil, Tomáš (advisor)
The work deals with the use of secondary raw materials in the self-leveling floor systems when used as a secondary raw material perform here especially classic ash, boiler slag and gypsum from flue gas. Work is looking for ways in as much as possible to replace conventional materials used in self-leveling flooring systems, secondary energy products. The aim of this work is to determine the optimal amount and ratio of secondary raw materials in self-leveling flooring compounds so that they are maintained or improved standard properties of these compounds reported in the standards. The work is divided into several points, the first point was first sought appropriate composite binder, where it was used as aggregates reach a standard sand. At other points the sand was then replaced by secondary materials. Were also tested ingredients to influence the rate of cooling, or for the onset of the initial strength.
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Supersulphates cements
Mohelská, Lucie ; Wirthová, Michaela (referee) ; Opravil, Tomáš (advisor)
The work is studying posibilities of use secondary materials produced by energetical industry. In fact it studies posibilities of preparing supersulphates cements with secondary raw materials. Its main system for simulation was used milled portland clinker. To clinker were added diferent secondary raw materials from energetical industry with sulphate. On prepared samples were watched mechanical properties in time. Tested were different samples of secondary raw materials.
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Possibilities of clay plasters shrinkage elimination
Melichar, Jindřich ; Koplík, Jan (referee) ; Opravil, Tomáš (advisor)
Earth plasters which are applicated in interiers don´t have just an estetic, but mainly heat storage function. To accomplish better storage properties the plaster has to be laid on the wall in sufficient thick ply. But this use to be accompained by creating of cracks during dehydration of the plaster. This bachelor work will be considering possibilities of elliminating this negative event by additing suitable components to suppress shrinkage and cracks by creating ettringite.
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