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Influence of grinding technology on the properties of blended cements with pozzolanic components.
Dočkal, Jakub ; Smetanová,, Lenka (referee) ; Dvořák, Karel (advisor)
The aim of this thesis was to summarize and assess the possibility of using recycled glass in the manufacture of blended portland cements. Work was focused on examining the possibilities to improve pozzolanic properties of recycled glass with new milling processes. The formation of agglomerates material during the course of grinding and their subsequent effect on the hydration process of binders has been also examining. Part of the thesis was also focused on grindability of materials and determination of using separate or inters grinding.
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Development of phase composition in silicate systems by available methods and their optimalization
Opravilová, Lenka ; Palou, Martin (referee) ; Škvára, František (referee) ; Havlica, Jaromír (advisor)
One of the most prominent measurable parameters of the development of phases and phase transformations in inorganic systems are undoubtedly the volume changes of silicate matrix. The study of volume changes is crucial in the terms of usable durability of final product. They represent shrinkage or expansion of the material and may lead to significant decrease of technological and ecological parameters and often to complete destruction of these materials. Most often the volume changes can be observed when cement is used as a binder and in concretes, mortars, artificial aggregates and other similar materials. There are many methods to detect, define and determine the volume changes qualitatively or quantitatively. The development of phases was investigated as a part of the dissertation thesis and hence the volume changes were observed under the conditions closest to the real state in the construction industry. The raw materials and admixtures were selected which model the content of hazardous components present in conventional materials (both natural and secondary), used in construction and the relationship with volume changes was searched and demonstrated. The contacts for measuring the volume changes were attached to test surfaces of specimens and the physical - mechanical tests (volume changes, phase changes, strength, etc.), chemical analysis and ecotoxicity tests depending on the length of hydration were performed.
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Influence of Zinc in Byproducts on Hydration and Properties of Blended Portlands Cements
Šilerová, Iva ; Palou, Martin (referee) ; Rovnaníková, Pavla (referee) ; Havlica, Jaromír (advisor)
The theme of this work is to monitor the effect of zinc on the properties of blended Portland cements. Zinc was tested in the form of two-soluble salts: Zn(NO3)22 H2O and ZnCl2 and a very slightly soluble compound ZnO. Blended cements were prepared by partial replacement with finely ground granulated blast furnace slag, high-temperature and fluidized bed combustion filter fly ash. Flow properties were studied on the prepared pastes. Impact on hydration reactions was examined by using of isothermal and isoperibolic calorimetry. Flexural and compressive strength were measured as mechanical properties of the prepared test specimens. The phase composition of the prepared composites and incorporation of zinc ions in the cement matrix via leaching tests and FTIR analyzes were also studied. Microstructure development of cement samples was tested by SEM analysis with EDS. Influence on ecotoxicity was also measured.
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Study of volume changes of binders silicate
Nováček, Jaroslav ; Rovnaníková, Pavla (referee) ; Steuer,, Radek (referee) ; Pavlík,, Zbyšek (referee) ; Šťastník, Stanislav (advisor)
In theory, this work is devoted to the principles and methods of measurement of volume changes of mortars and concretes. Emphasis is placed on cement self-levelling screeds with initial shrinkage compensation. In the practical part of the work is devoted to the development of prototype measuring system designed for non-contact detection of volume changes hydrating silicate. Using the new measurement method is also practically examined the influence of boundary conditions on hydration volume changes of selected silicate binders, cement mortar and cement levelling compound based on four different connective concepts. In the calculation, this work focuses on the numerical modelling of volume changes of the examined compounds.
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Systems of self-setting foundry mixtures on the base portland cements
Janíčková, Petra ; Cupák, Petr (referee) ; Rusín, Karel (advisor)
The project elaborated in frame of engineering studies branch N2332-00. The project is submitting design of technology production sand mixture with cement binder – Portland binder CEM I 42,5 N. Pursuant to of the literary pursuit a problem of the sand mixture with cement binder was tested few sand mixture. As optimal composition it turned out application sand mixture with 2 % CaCl2 content and 1 – 2 % Dextrin content. Sand mixture with cement has good moulder and regenerating.
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Possibilities of using recycled glass for the preparation of blended cements
Dobrovolný, Petr ; Všianský,, Dalibor (referee) ; Dvořák, Karel (advisor)
This work focuses on the possibility of using recycled glass in the manufacture of blended portland cements. It examines the possibilities to improve pozzolanic properties of recycled glass with new milling processes, the formation of agglomerates material during the course of grinding and their subsequent effect on the hydration process of binders. It is also the optimization of the grinding process with respect to the wear of grinding bodies, grinding energy consumption and maximize the performance of the mill.
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