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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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Study of durability of binders concept on purposeful creation of ettringite
Sokolt, Stanislav ; Štenko,, Miroslav (referee) ; Žižková, Nikol (advisor)
This master thesis is focused on the binary and ternary systems with connective purposeful ettringite formation for fast hardening adhesive for ceramic tiles. It deals with the durability of these materials after exposure to the corrosive environment. It examines the physical and mechanical properties and mineralogy changes after exposure to corrosive environments. Within processing of this paper provides basic information concerning the connective concept of purposeful formation of ettringite.
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Effect of pH of mixing water on hydration and mechanical properties of cement composites.
Bezděk, Ondřej ; Krátký, Josef (referee) ; Šiler, Pavel (advisor)
This master’s thesis is focused on the effect of mixing water pH value on hydration and mechanical properties of cement composites based on portland cement. Source material was CEM I 42,5 R. Hydration process was analyzed by isoperibolic calorimetry, X-ray diffraction analysis and differential thermal analysis. Compressive and flexural strength was examined as mechanical properties. The samples microstructure was observed by scanning electron microscopy. Influence of mixing water pH value on flexural and compressive strength, retardation of hydration and ratio of individual phases was shown.
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