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Economic aspects of environmental use of building materials based on secondary raw materials.
Ťažký, Tomáš ; Durica,, Tibor (referee) ; Sedlmajer, Martin (referee) ; Nosek,, Karel (referee) ; Kulísek, Karel (advisor)
The disses thesis is focused on usage of secondary raw materials from the electric power industry, specifically fly ash as a component for the building industry, concentrated on concrete. Two main streams are covered, environmental and economical. Reasons, which led to focus on the selected subject are coming mainly from the scarcity and availability of high-quality mineral resources, environmental pressure for usage of industry byproduct, reducing emissions and economical pressure to reduce production cost, especially raw materials. The main purpose of the work was to verify the possibility of increasing the usability of fly ash as a mineral additive in the technology of concrete production with materials retrieved from coal fired power plants and applying mechanical activation of fly ash. The main goal of the experimental part of work was to demonstrate improvement of fresh and hardened concrete properties as a main condition to support economic efficiency of mechanical activated fly ash. Base on previous facts the methodology was covering two main areas, the experimental and the assessment. Relatively large sets of tests were performed, using a wide range of tested high temperature fly ash and fluidized bed combustion fly ash granulometrically treated, by mixing and grinding. Results of the testing confirmed focused parameters for concrete and mortar mechanical properties, total economical efficiency of the targeted solution and the subject of the dissertation. In the experiment section has been retrieved valuable findings contributing to the overall knowledge of the faculty, also for the practical application. The results of the tests confirmed the achievement of the planned target parameters, both in terms of physical and mechanical properties of experienced mortars and concretes, as well as the overall economic efficiency of the proposed design and the topic of the disses thesis. Within the experimental work, valuable professional knowledge and benefits w
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Research of effective use and activation of activ concrete additions
Mikhailova, Olesia ; Ťažký, Tomáš (referee) ; Hela, Rudolf (advisor)
The theoretical part describes the admixtures that are used in cement replacement. Here also summarizes the findings on the influence of granulomentry, grain shape and fineness of admixtures on the density of the cement matrix. The practical part is experimentally verified the influence of fineness admixtures and grain size on the mechanical properties of concrete. Also, the rheological properties of cement are compared with admixtures depending on the type and dosage and time.
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Granulometry of solid particles
Klimeš, Jiří ; Uher, Miroslav (referee) ; Beneš, Petr (advisor)
This bachelor thesis deals with a real-time granulometry measurement of granulate flow with acoustic emission sensors. Thesis is focused on coal granulometry measurement in thermal power stations. Parameters were introduced in time and frequency domain describing the granulometry of measured medium. The second part is focused on granulometry measurement experiment. Parameters were calculated for reference samples of material and they were evaluated. Third part of this thesis deals with finding correlations between process variables and selected parameters
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Study of the grindability of the clinker minerals
Červinková, Lenka ; Všianský,, Dalibor (referee) ; Dvořák, Karel (advisor)
The thesis deals with the influence of free various technological grinding processes of pure clinker minerals. The goals is to synthetically prepare pure clinker minerals and monitor the effect of the duration of the grinding process and monitor the impact of grinding technology on their crystallinity. A laser granulometry and XRD analysis are used for evaluation.
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Optimizing the composition of micro concrete admixtures.
Juříková, Denisa ; Křížová, Klára (referee) ; Hela, Rudolf (advisor)
The aim of this paper is to summarize knowledges related to the use of fine-grained admixtures in cement composites. By utilizing of these admixtures it is possible to achieve extreme properties, especially high strenght and durability of concrete. These properties can be achieved by optimizing the density of the binder and filler in range of 0 to 0,25 mm. Therefore, large part of thesis is focused on admixtures and its effect on concrete. The experimental part of the thesis deals with optimization od selected admixtures in combination with cement to achieve the minimum of the voids and their compressive strenght were determined at 1, 3, 7, 28 and 60 days.
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Optical granulometry
Dohnálek, Martin ; Richter, Miloslav (referee) ; Kunz, Jan (advisor)
This diploma thesis deals with the topic of macroscopic particle size detection during freefall using computer vision. The measurement results can be used to verify other granulometric methods, or in the industry as a simpler alternative to conventional methods. Particle sampling takes place in flight and particles may overlap. Because of this, the data is recorded by a high-speed camera on the scene with fit-to-purpose lighting. The components of the proposed algorithm are: background removal, localization of potential particles, segmentation using the watershed method, determination of particle size. Using image correlation, the fall velocity and the number of particles in the sample are also determined. Experiments confirmed that the measured particle sizes of the sample correspond to the sizes determined by the traditional sieving method and are consistent even on repeated measurements. The correctness of the speed determination was verified by a theoretical calculation. When determining the effect of the sample’s dustiness on the quality of detection, resistance to the presence of dust up to 10% of the sample weight was found.
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Economic aspects of environmental use of building materials based on secondary raw materials.
Ťažký, Tomáš ; Durica,, Tibor (referee) ; Sedlmajer, Martin (referee) ; Nosek,, Karel (referee) ; Kulísek, Karel (advisor)
The disses thesis is focused on usage of secondary raw materials from the electric power industry, specifically fly ash as a component for the building industry, concentrated on concrete. Two main streams are covered, environmental and economical. Reasons, which led to focus on the selected subject are coming mainly from the scarcity and availability of high-quality mineral resources, environmental pressure for usage of industry byproduct, reducing emissions and economical pressure to reduce production cost, especially raw materials. The main purpose of the work was to verify the possibility of increasing the usability of fly ash as a mineral additive in the technology of concrete production with materials retrieved from coal fired power plants and applying mechanical activation of fly ash. The main goal of the experimental part of work was to demonstrate improvement of fresh and hardened concrete properties as a main condition to support economic efficiency of mechanical activated fly ash. Base on previous facts the methodology was covering two main areas, the experimental and the assessment. Relatively large sets of tests were performed, using a wide range of tested high temperature fly ash and fluidized bed combustion fly ash granulometrically treated, by mixing and grinding. Results of the testing confirmed focused parameters for concrete and mortar mechanical properties, total economical efficiency of the targeted solution and the subject of the dissertation. In the experiment section has been retrieved valuable findings contributing to the overall knowledge of the faculty, also for the practical application. The results of the tests confirmed the achievement of the planned target parameters, both in terms of physical and mechanical properties of experienced mortars and concretes, as well as the overall economic efficiency of the proposed design and the topic of the disses thesis. Within the experimental work, valuable professional knowledge and benefits w
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Granulometry of solid particles
Klimeš, Jiří ; Uher, Miroslav (referee) ; Beneš, Petr (advisor)
This bachelor thesis deals with a real-time granulometry measurement of granulate flow with acoustic emission sensors. Thesis is focused on coal granulometry measurement in thermal power stations. Parameters were introduced in time and frequency domain describing the granulometry of measured medium. The second part is focused on granulometry measurement experiment. Parameters were calculated for reference samples of material and they were evaluated. Third part of this thesis deals with finding correlations between process variables and selected parameters
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