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Lime Mortars Modified by Fine Ground Brick Body
Šmerdová, Ludmila ; Vyšvařil, Martin (referee) ; Rovnaníková, Pavla (advisor)
Natural pozzolanic materials played an important role in Ancient architecture. In the last decades and nowadays it is artifical pozzolan which especially finds its use as an additive to mortar and concrete to improve some, especially the mechanical properties. This master thesis deals with study of pozzolan type of fine brick powder which is a by-product of the production of calibrated bricks. Along with studying pozzolanic activity of brick powder, lime mortar with different proportions of brick powder as an additive or replacement of lime dust are investigated. What is observed is its impact on the consistency of these mortar, water absorption, strength in time or fracture-mechanical parameters of mortar. The results may indicate the possible potential use of this source of pozzolanic admixture in lime mortar and plaster which are nowadays mainly used for the restoration of facades of historic buildings.
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The influence of hydration accelerators on cement doped with zinc
Beneš, Pavel ; Šilerová,, Iva (referee) ; Šiler, Pavel (advisor)
Zinc in cement has negative properties mainly due to a significant delay in hydration. This bachelor thesis deals with the study of hydration of cements containing zinc. The course of cement hydration was monitored by isoperibolic calorimetry. Zinc was doped to CEM I 42.5 R in the form of 1 weight percent zinc oxide. Calcium oxide, formic acid and calcium formate were used in various proportions as accelerators. The obtained results were compared with the measured strengths and finally the suitability of the given accelerators was discussed for use in construction application.
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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 hydration accelerators on zinc - doped cement mortars
Beneš, Pavel ; Šilerová, Iva (referee) ; Šiler, Pavel (advisor)
This work deals with monitoring the hydration of cement mortars and cement pastes made from CEM I 42.5 R cement doped with zinc oxide in an amount of 1 % wt. To eliminate the delay in the onset of hydration due to the presence of zinc oxide, the following accelerators were added to the cement mixtures in different proportions: calcium oxide, formic acids and calcium formate. Hydration was monitored using isoperibolic calorimetry. Furthermore, the mechanical properties of mixtures were investigated, namely the tensile strength after bending and the compressive strength after 7 days and after 28 days. The cement mortars were further subjected to additional analyses, such as porosimetry, DTA/TG and SEM.
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Influence of CaO Content on Specific LCC, ULCC and NCC Properties
Zemánek, David ; Nevřivová, Lenka
Castables are widely used refractory materials with variable applications. Three types of castables (low cement, ultra-low cement and no cement) were tested to compare their specific properties. Also, corrosion resistance test as an important factor influencing castables design was carried out. Potassium carbonate was used as a corrosive medium using static crucible method. The corrosion mechanisms were evaluated by Scanning Electron Microscopy (SEM) and X-ray Diffraction (XRD). The results confirmed that the presence of higher amount of calcium oxide from the Calcium Aluminate Cement (CAC) leads to formation of calcite and anorthite. The corrosion resistance was improved with decreasing or replacing the hydraulic bond.
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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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The influence of hydration accelerators on cement doped with zinc
Beneš, Pavel ; Šilerová,, Iva (referee) ; Šiler, Pavel (advisor)
Zinc in cement has negative properties mainly due to a significant delay in hydration. This bachelor thesis deals with the study of hydration of cements containing zinc. The course of cement hydration was monitored by isoperibolic calorimetry. Zinc was doped to CEM I 42.5 R in the form of 1 weight percent zinc oxide. Calcium oxide, formic acid and calcium formate were used in various proportions as accelerators. The obtained results were compared with the measured strengths and finally the suitability of the given accelerators was discussed for use in construction application.
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|
Lime Mortars Modified by Fine Ground Brick Body
Šmerdová, Ludmila ; Vyšvařil, Martin (referee) ; Rovnaníková, Pavla (advisor)
Natural pozzolanic materials played an important role in Ancient architecture. In the last decades and nowadays it is artifical pozzolan which especially finds its use as an additive to mortar and concrete to improve some, especially the mechanical properties. This master thesis deals with study of pozzolan type of fine brick powder which is a by-product of the production of calibrated bricks. Along with studying pozzolanic activity of brick powder, lime mortar with different proportions of brick powder as an additive or replacement of lime dust are investigated. What is observed is its impact on the consistency of these mortar, water absorption, strength in time or fracture-mechanical parameters of mortar. The results may indicate the possible potential use of this source of pozzolanic admixture in lime mortar and plaster which are nowadays mainly used for the restoration of facades of historic buildings.
|
|
|
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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