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Effect of water-lime ratio on the properties of lime mortars.
Kurfürstová, Nela ; Vyšvařil, Martin (referee) ; Rovnaníková, Pavla (advisor)
Diploma thesis gives a brief description of the traditional technology of preparation of lime mortars for restoration of historical buildings. The theoretical part is focused on the preparation of lime mortars traditional methods, using appropriate materials for making and influence amount of water. Attention is also paid to the events that take place in the setting and hardening of lime mortar. In the experimental part of the research was conducted, which aimed to assess the influence of water-cement ratio and mixing ratio (binder to filler) on the properties of lime mortars. At various times were measured mechanical properties, density, shrinkage, frost resistance and porosity. The mortar was also carried out thermal analysis and found to contain calcium carbonate. Acquired knowledge could help in the reconstruction of historical buildings.
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Influence of cellulose ethers on rheological properties of lime
Hegrová, Michaela ; Rovnaník, Pavel (referee) ; Vyšvařil, Martin (advisor)
The subject of this diploma thesis is a study of the influence of cellulose ethers on the rheological properties of lime. The theoretical part focuses on rheological parameters, techniques and test equipment used in rheology measurements. Various types of cellulose ethers and their influence on the rheological properties of fresh mortars are described. The practical part deals with the study of the influence of different types and quantities of cellulose ethers on the properties of fresh lime pastes and mortars. The results were obtained from measurements on a rotational rheometer with a special geometry for building materials. Measuring methods used were flow and oscillatory tests. Yield stress, viscosity and flow index were determined by the flow measurement. The stability and stiffness of fresh materials were determined during the oscillation measurements. The measured results are then evaluated and compared.
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Rheological behaviour of alkali-activated aluminosilicates
Ševčík, Marek ; Vyšvařil, Martin (referee) ; Rovnaník, Pavel (advisor)
The bachelor thesis is focused on rheological properties of alkali activated materials, the main focus is on rheological behavior of geopolymers. The theoretical part describes the most commonly used materials for the preparation of geopolymers. Further, described rheology in general and rheological properties are described, types of behavior of substances and differences between rheological properties of different types of aluminosilicates are explained. In the experimental part, mechanical properties of geopolymer pastes based on metakaolin and fly ash with different silicate moduli of alkaline activator – water glass were investigated. For these materials, rheometric measurements and rheological behavior were also performed.
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Effect of cellulose ethers on properties of hydraulic lime
Skoupil, Jakub ; Rovnaníková, Pavla (referee) ; Vyšvařil, Martin (advisor)
This diploma thesis deals with the study of the influence of cellulose ethers on the properties of hydraulic lime mortars. The availability and price of cellulose ethers in the industrial market is very favorable, but we can´t meet with studies using cellulose ethers in building materials, where lime is used as a binder. Cellulose ethers are commonly used as thickening agents in cement-based materials. The purpose of this diploma thesis is to review if cellulose ethers are appropriate for use in hydraulic lime mortars, either as water retention agents that contribute by water retention to better hydration of hydraulic binder components or to affect the properties of mortar in the fresh state. The theoretical part is dedicated to cellulose ethers, especially their production and how they influence the properties of building materials. In the practical part, the thesis deals with the influence of the dose of five different types of cellulose ethers on the properties of hydraulic lime. The properties in the fresh state and the physical-mechanical properties of mortars were monitored over time.
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Effect of Grain Size of Waste Glass on Properties of Alkali Activated Aluminosilicate Composites
Novák, Václav ; Vyšvařil, Martin (referee) ; Bayer, Patrik (advisor)
The diploma thesis is focused on the use of the waste glass with different fineness on alkali - activated composites, mainly based on slag and fly ash. The theoretical part is focused on materials that are most used for alkaline activation - slag, fly ash and their composites with waste glass. The theoretical part also deals with the alkaline activation of composites from these materials and the factors that influences the microstructure and properties of these composites. In the experimental part were prepared composites from slag and fly ash with a waste glass as substitute. These composites then have been examined on mechanical properties and microstructure, also how different fineness of glass influences these properties. Then it will be decided whether it is economically advantageous grinding waste glass to finer fractions
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Effect of aggregate type on lime mortar rheology
Vozák, Rastislav ; Rovnaník, Pavel (referee) ; Vyšvařil, Martin (advisor)
The subject of this bachelor thesis is examining the effect of aggregate type on lime mortar rheology. In the theoretical part, the thesis describes types of liquids and basic rheological quantities. Afterwards there are described some of the rheological behaviour models of non-Newtonian fluids. Furthermore, the theoretical part characterizes measurement of the flow, devices used for the measurement including the oscillatory measurement and its individual modes. Scientific literature was used to describe the rheology of the lime mortars and it covers the effect of different additives on the rheological behaviour. There is also characterized the effect of aggregate on the properties of lime mortars. The experimental part talks about the effect of three various kinds of aggregate on rheological prop-erties of the fresh lime mortar. The chemical composition of aggregates and their granulometry was determined. Subsequently, flow measurements were carried out and evaluated into flow curves. The yield stress, coefficient of consistency and flow index were assayed. In the oscillatory measurement there were measured complex, elastic and viscous modulus and loss factor.
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Influence of cellulose ethers on rheological properties of lime
Hegrová, Michaela ; Rovnaník, Pavel (referee) ; Vyšvařil, Martin (advisor)
The subject of this diploma thesis is a study of the influence of cellulose ethers on the rheological properties of lime. The theoretical part focuses on rheological parameters, techniques and test equipment used in rheology measurements. Various types of cellulose ethers and their influence on the rheological properties of fresh mortars are described. The practical part deals with the study of the influence of different types and quantities of cellulose ethers on the properties of fresh lime pastes and mortars. The results were obtained from measurements on a rotational rheometer with a special geometry for building materials. Measuring methods used were flow and oscillatory tests. Yield stress, viscosity and flow index were determined by the flow measurement. The stability and stiffness of fresh materials were determined during the oscillation measurements. The measured results are then evaluated and compared.
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Effect of cellulose ethers on mechanical properties of lime mortar
Skoupil, Jakub ; Bayer, Patrik (referee) ; Vyšvařil, Martin (advisor)
The subject of the thesis is to conduct an extensive literature review on the topic of effect of cellulose ethers on the mechanical properties of lime mortars. The theoretical part is devoted to the composition and production of cellulose ethers, which are available on the industrial market. On the basis of the review, the design of lime mortars using different kind of cellulose ethers has been conducted and after curing the tests of mechanical properties of mortars were performed and evaluated.
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The effect of aggregate type on the properties of lime mortar
Žižlavský, Tomáš ; Rovnaníková, Pavla (referee) ; Vyšvařil, Martin (advisor)
The thesis is focused on the comparison of the role of different types of aggregates and the binder-aggregate ratio on the properties of lime mortars. The theoretical part of the thesis deals with the effect of properties of aggregate, a binder-aggregate ratio and a use of calcareous aggregate, especially limestone, on the properties of mortars. It also deals with the utilization of limestone as aggregate in a history of masonry. In the practical part of the thesis there is a comparison of physically-mechanical and microstructural properties of mortars prepared with different type of aggregate (siliceous sand and limestone aggregate), with varying binder-aggregate ratio and also with a partial substitution of the aggregate by limestone fines. It was found that the usage of limestone instead of quartz sand produces the mortar of comparable properties. The partial substitution of the aggregate with limestone fines caused noticeable growth of strength, especially in mortars with higher binder-aggregate ratio.
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Effect of admixtures on the properties of metakaolin geopolymer
Halasová, Kristýna ; Vyšvařil, Martin (referee) ; Rovnaník, Pavel (advisor)
Geopolymers are amorphous to semi-crystalline aluminosilicate polymers which are formed from inorganic polycondensation reaction of a solid aluminosilicate precursor with an alkaline sodium hydroxide or silicate. The resulting materials exhibit high durability, resistance to aggressive environments, high temperature resistance and many other properties that make them have received much attention in recent years, not only in construction. This thesis describes the influence of additives commonly used in concrete and mortar (water reducing, superplasticizer, air-entraining, foamer and defoamer, anti-shrinkage, stabilization) on the behavior of metakaolin in geopolymer fresh and hardened state. It describes metakaolin geopolymer effect on rheological properties of fresh mixtures, compressive strength and flexural strength after 28 days and a density in the fresh and hardened state.
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