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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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Comparison of microstructure of standard and modified fly ash autoclaved aerated concrete
Fleischhacker, Ján ; Kulísek, Karel (referee) ; Drochytka, Rostislav (advisor)
Nowadays, the amount of produced fly ash and fluidized ash is huge, so it is important to find ways of its proper use.Significant influence in field of fly ash consumption is production of autoclaved aerated concrete. Most important factor in production is properties of raw materials such as mineralogical and chemical composition. The study of raw materials is important to understand the mechanism of hydratation, tobermorite formation and mineralogy of final product. In present study, we investigate influence of raw materials to mineralogy of autoclaved aerated concrete, significantly to influence of fluidized ash on quality of autoclaved aerated concrete. Closure of study is design of the methodology, specialized in field of bachelor’s thesis study.
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The effect of fly ash aerated concrete production technology to formation of tobermoritic phases
Fleischhacker, Ján ; Kulísek, Karel (referee) ; Drochytka, Rostislav (advisor)
Autoclaved aerated concrete is long-time ecological building material with usefull properties. There needs to be done research of its mineralogical compound for reengineering the production. The main mineral compound of AAC is tobermorite, it increases its mechanical properties. In the presence study, we examine the usage of nature and artificial silicious materials. Also, we investigate the influence of sulfate and alumina admixtures, as well as fluidized bed combustion ash, which can be used as the lime and gypsum replacement. Closure of the study is design of the optimal raw material composition, also hydrothermal treatment of autoclaved aerated concrete. In relation to its mechanical properties, mineralogical composition and cost.
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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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The effect of fly ash aerated concrete production technology to formation of tobermoritic phases
Fleischhacker, Ján ; Kulísek, Karel (referee) ; Drochytka, Rostislav (advisor)
Autoclaved aerated concrete is long-time ecological building material with usefull properties. There needs to be done research of its mineralogical compound for reengineering the production. The main mineral compound of AAC is tobermorite, it increases its mechanical properties. In the presence study, we examine the usage of nature and artificial silicious materials. Also, we investigate the influence of sulfate and alumina admixtures, as well as fluidized bed combustion ash, which can be used as the lime and gypsum replacement. Closure of the study is design of the optimal raw material composition, also hydrothermal treatment of autoclaved aerated concrete. In relation to its mechanical properties, mineralogical composition and cost.
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Comparison of microstructure of standard and modified fly ash autoclaved aerated concrete
Fleischhacker, Ján ; Kulísek, Karel (referee) ; Drochytka, Rostislav (advisor)
Nowadays, the amount of produced fly ash and fluidized ash is huge, so it is important to find ways of its proper use.Significant influence in field of fly ash consumption is production of autoclaved aerated concrete. Most important factor in production is properties of raw materials such as mineralogical and chemical composition. The study of raw materials is important to understand the mechanism of hydratation, tobermorite formation and mineralogy of final product. In present study, we investigate influence of raw materials to mineralogy of autoclaved aerated concrete, significantly to influence of fluidized ash on quality of autoclaved aerated concrete. Closure of study is design of the methodology, specialized in field of bachelor’s thesis study.
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