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Studium a vývoj polymer-cementových kompozitů s důrazem na vysoký obsah druhotných surovin a kompenzaci objemových změn
Hermann, Radek ; Bydžovský, Jiří (referee) ; Reitermann, Pavel (referee) ; Kolísko, Jiří (referee) ; Drochytka, Rostislav (advisor)
Reducing of humanity's carbon footprint is currently one of the main directions of global research. Another significant problem is the disposal, recycling and secondary use of waste materials produced from a wide range of industries and municipal waste. This thesis deals with the problematics of polymer-cement composites, which are most often used for rehabilitation, reprofiling and structural repairs, especially of concrete structures. The thesis examines and verifies the possibilities of utilization of a large amount of secondary raw materials and waste as a substitute for cement as a primary binder. At the same time, the work deals with the full replacement of the primary filler with waste raw materials, for which there is currently no other use. The work also addresses and verifies the influence of several commonly available commercial polymer dispersions. The work deals with the use of liquid, but also powdered polymeric additives of various bases. The work also deals with the problematics of volume changes of the hydration process of polymer-cement composites and the effect of volume changes on the physical-mechanical properties of composites. The influence of volume changes that occur during the hydration of polymer-cement composites is a significant criterion in the selection and use of these composites. The volume changes of the material have a great influence especially on the maximum layer thickness and the maximum area that can be repaired with the material without the risk of cracks and the need to create a working joint. The results of this work are associated with a reduction in the economic and environmental impacts of production and use of polymer-cement building materials and increase the usability of these materials mainly due to the possibility of remediation of larger areas than previously possible.
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Analýza vlastností vláknocementových kompozitních materiálů
Hoško, Marek ; Bydžovský, Jiří (referee) ; Reitermann, Pavel (referee) ; Pavlík,, Zbyšek (referee) ; Bodnárová, Lenka (advisor)
Thesis theme was the issue of sludge waste generated during the production of fiber cement and its reverse implementation into the matrix. The theoretical part of the work has deal with description of Hatschek's fiber cement production technology, technological water system, sludge management and its separation from the system. Experimental part was divided into 5 stages. The first stage was focused on monitoring the qualitative parameters of the sludge waste, which were monitored using selected qualitative tests. In the next stage, was compared the mineralogical and chemical composition of the sludge waste samples with the standard slurry used for production. In the third stage was proposed an alternative method of producing laboratory samples, on which the influence of the addition of sludge on the strength characteristics was verified. In the next step were summarized the results from the previous stages and recipes with waste sludge for production on the production machine were proposed. The fourth stage dealt with the sludge processing itself, its collection and dosing. During the wet production process were evaluated a number of important indicators of the efficiency of production of fiber cement products. Among the most important of them belong percolation and retention evaluation. In the last stage were compared the produced samples with sludge with the standard ones. The samples were subjected to a series of physical-mechanical and durability tests: longitudinal and transverse strength, density, watertightness, impact test, frost resistance, soak-dry, hidden defect method, dimensional stability and warping. The result of the thesis is a comprehensive study on the properties and implementation of sludge waste into fiber cement.
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SYNTHESIS AND DETERMINATION OF PROPERTIES OF PURE PHASES OF PORTLAND CLINKER AND THEIR POLYMORPHS
Ravaszová, Simona ; Keppert, Martin (referee) ; Reitermann, Pavel (referee) ; Palou, Martin (referee) ; Dvořák, Karel (advisor)
Quantitative diffraction analysis is currently carried out through Rietveld analysis, which is able to decode the various diffraction lines on a diffraction record, provided that the structural model for each clinker phase is well known. The subject of this dissertation is the laboratory preparation of pure phases of one triclinic and two monoclinic polymorphs of the main clinker mineral alite, which will serve as standards for the calibration of powder X-ray diffraction analysis. The result of this work will be detailed procedures for the preparation of individual polymorphs of alite and calibration relationships for unambiguous and easier identification of monoclinic polymorphs in real clinkers.
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