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Brickmaking grogs and their thermo-dilatometric determination
Hladík, Václav ; Skotal, Zbyněk (referee) ; Sokolář, Radomír (advisor)
Main focus of the bachelor´s thesis is use of rock waste fraction as an alternative raw material to traditional quartz sand. Effect of this substitution on ceramic produts properties is outlined. Key properties are water absorption, flexural strength and compressive strength. The practical part traces the potential of alternative grogs. Their behavior is monitored by DKTA analysis, water absorption tests and strength tests. Thesis includes author´s suggestion of an optimal grog based on publications and results of the practical part.
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Lime mortars with the addition of ground limestone
Žižlavský, Tomáš ; Rovnaníková, Pavla (referee) ; Vyšvařil, Martin (advisor)
The thesis is focused on an effect of addition of ground limestone on properties of lime based mortars. Theoretical part of the thesis deals with diferenciation of plasters and their utilization, history of using limestone as an aggregate, its exploitation in the present and its impact on properties of lime based plasters, specially on strenghts. In the next part there's elaborated the carbonation reaction including the influence of external agents. Practical part of the thesis is focused on proving assumtions from theoretical part, particulary on the influence of ground limestone on the strenght properties of lime based plasters.
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Hybrid dental composites combining short fibers and particulate fillers
Klieštiková, Nikola ; Přikryl, Radek (referee) ; Bystřický, Zdeněk (advisor)
This work deals with the hybrid composite material combining particulate filler with short fibers for dental applications. The barium micro-filler and the short glass fibers were treated with -methacryloxypropyltrimethoxysilane in cyclohexane using n-propylamine. The barium micro-filler and the short glass fibers were mixed with the matrix based on a dimethacrylate resin. The effects of the addition of short glass fibers on mechanical properties were studied. Surface treatment of the filler was characterized by thermogravimetric analysis (TGA) and diffuse reflectance infrared fourier transform spectroscopy (DRIFTS). Fracture surfaces and the adhesion to the matrix was observed by scanning electron microscope (SEM). The modulus of elasticity and strenght was determined by three point bending flexural test. Critical values of the stress intensity factor annd energy release rate were determined using the three point bending flexural test of notched specimens. The particulate filler increased the flexural modulus of elasticity and fragility. The addition of short fibers had little effect on flexural modulus of elasticity, but increased the flexural strength and fracture toughness of the specimen.
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Influence of zinc on mechanical properties of cement composites
Štarha, Tomáš ; Šilerová,, Iva (referee) ; Šiler, Pavel (advisor)
The theme of this bachelor thesis is to monitor the effect of zinc on mechanical properties of portland cement. Zinc was tested in the form of zinc oxide. Three acceleration additives were added, calcium oxide, formic acid and calcium formate in various proportions. Furthermore, the mechanical properties of all these mixtures were monitored by measuring flexural strength and compressive strength at 7 and 28 days after mixing and mixtures were analyzed by XRD and DTA. Also using isoperibolic calorimetry, the hydration of CEM 42.5 R cement zinc oxide was monitored.
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Results of Anorthite Creation in ceramic Body
Beránková, Karla ; Šveda,, Mikuláš (referee) ; Sokolář, Radomír (advisor)
Anorthite is crystalline phase in the ceramic body. Is acquired on burning a mixture of calcium ceramic raw material. This work deals with the influence on the resulting properties of anorthite ceramic body, especially flexural strength, porosity, shrinkage, thermal expansion coefficient. And the influence of different CaO sources on the properties. As a source of CaO was used calcium carbonate, calcium hydroxide and fluid fly ash.
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Influence of zinc on mechanical properties of cement composites
Štarha, Tomáš ; Šilerová,, Iva (referee) ; Šiler, Pavel (advisor)
The theme of this bachelor thesis is to monitor the effect of zinc on mechanical properties of portland cement. Zinc was tested in the form of zinc oxide. Three acceleration additives were added, calcium oxide, formic acid and calcium formate in various proportions. Furthermore, the mechanical properties of all these mixtures were monitored by measuring flexural strength and compressive strength at 7 and 28 days after mixing and mixtures were analyzed by XRD and DTA. Also using isoperibolic calorimetry, the hydration of CEM 42.5 R cement zinc oxide was monitored.
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Brickmaking grogs and their thermo-dilatometric determination
Hladík, Václav ; Skotal, Zbyněk (referee) ; Sokolář, Radomír (advisor)
Main focus of the bachelor´s thesis is use of rock waste fraction as an alternative raw material to traditional quartz sand. Effect of this substitution on ceramic produts properties is outlined. Key properties are water absorption, flexural strength and compressive strength. The practical part traces the potential of alternative grogs. Their behavior is monitored by DKTA analysis, water absorption tests and strength tests. Thesis includes author´s suggestion of an optimal grog based on publications and results of the practical part.
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Hybrid dental composites combining short fibers and particulate fillers
Klieštiková, Nikola ; Přikryl, Radek (referee) ; Bystřický, Zdeněk (advisor)
This work deals with the hybrid composite material combining particulate filler with short fibers for dental applications. The barium micro-filler and the short glass fibers were treated with -methacryloxypropyltrimethoxysilane in cyclohexane using n-propylamine. The barium micro-filler and the short glass fibers were mixed with the matrix based on a dimethacrylate resin. The effects of the addition of short glass fibers on mechanical properties were studied. Surface treatment of the filler was characterized by thermogravimetric analysis (TGA) and diffuse reflectance infrared fourier transform spectroscopy (DRIFTS). Fracture surfaces and the adhesion to the matrix was observed by scanning electron microscope (SEM). The modulus of elasticity and strenght was determined by three point bending flexural test. Critical values of the stress intensity factor annd energy release rate were determined using the three point bending flexural test of notched specimens. The particulate filler increased the flexural modulus of elasticity and fragility. The addition of short fibers had little effect on flexural modulus of elasticity, but increased the flexural strength and fracture toughness of the specimen.
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