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Low energy cements based on clinker phases
Šmeral, Miloslav ; Koplík, Jan (referee) ; Bartoníčková, Eva (advisor)
This thesis deals with low-energy cements and the effect of dopants on their hydration, specifically copper and sulfur. The theoretical part summarizes the general information about clinker minerals, their low-energy/low-carbon alternatives and sustainability in the cement industry. Additionally, possible synthesis of clinker minerals are described. In the experimental part, methods for the preparation of doped tricalcium aluminate and the analysis of the synthesized products are presented. The sulfur doped tricalcium aluminate had the highest hydration heat. On the other hand, copper doped tricalcium aluminate and tricalcium aluminate in combination of these dopants exhibited lower hydration heat. The presence of the dopants also affected the composition of the hydration products.
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Design of repair material with reduced electrical impedance
Žáková, Karolina ; Černý, Vít (referee) ; Drochytka, Rostislav (advisor)
This bachelor's thesis focuses on designing a new composition of corrective material based on silicate with the aim of reducing electrical impedance. In the theoretical part, fundamental concepts necessary for understanding the topic will be described, such as terms related to conductivity, silicates, composites, and corrective materials in general. The experimental section includes the selection of raw materials, preparation, and testing of various compositions of corrective materials with different fillers. The impact of various additives on the electrical properties of the corrective material will be investigated, including its conductivity, resistivity, and cohesion. The final section summarizes and evaluates the achieved results.
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Aqueous CO2 Sequestration for Low-Carbon Ready-Mix Concrete
Chong, Yujie, Jamie ; Chua, Guan Feng ; Zhao, Mingshan ; Yip, Colin ; Daneti, Saradhi Babu ; Jin, Fei
The cement industry accounts for 8% of global energy- and process-related greenhouse gas emissions. To achieve global net-zero emission targets by 2050, the need for commercially ready low-carbon construction materials is becoming increasingly urgent. The fixation of captured carbon dioxide in concrete through CO₂ sequestration is a crucial area of study to reduce concrete embodied carbon. This paper discusses the development of a low-carbon ready-mix concrete (RMC) with aqueous CO2 sequestration, and the synergy between carbon dioxide and other constituent materials. The effectiveness of this approach was evaluated through mineralogical composition analysis using TGA, and the mechanical and rheological properties of various concrete mixes were studied. Aqueous CO2 sequestration using carbonated mixing water can stably fix up to 0.84% of CO2 by weight of cement within the cement matrix as CaCO3. The poor workability and incompatibility with GGBS that results from this approach were addressed by the inclusion of RCA as an external source of alkalinity and lubrication. This mix of low-carbon RMC has similar strength and rheological properties to conventional RMC and achieved an embodied carbon reduction of approximately 47%.
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Verification of the Applicability of Mixed Cement Types for the Production of Concrete Pavements
Klobása, Jan ; Hela, Rudolf
Concrete is the most widely used building material today. Due to the increase in the utility value of buildings, more and more emphasis is placed on the durability of buildings, which especially applies to concrete products exposed to frost and chemical deicing agents. Cement concrete pavements have the ability to transmit the effects of traffic and withstand adverse weather conditions. Concrete pavements can withstand high traffic loads without permanent deformations and have a long service life. However, it must be said that in the case of damage to the CB pavements, repairs require longer closures due to more demanding production and laying technology. The expected lifespan of a concrete road type is at least 30 years with basic and minimal maintenance, while the life cycle of tarmac roads is much shorter.
Currently, great importance is placed on reducing emissions arising from industrial production, especially cement production, where it is stated that the production of 1 ton of cement produces approximately 0.6 tons of CO2. Reducing emissions is possible thanks to secondary raw materials that are produced in large volumes in the Czech Republic, for which a suitable use is being sought.
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Utilisation of already deposited energy by-products in cement production
Lukášek, David ; Švec, Jiří (referee) ; Opravil, Tomáš (advisor)
This bachelor thesis focuses at study of deposited high-temperatured fly ash and its utilization in production of cement. The theoretical part of the bachelor thesis deals with the production and division of cements. The individual advantages and disadvantages of high-temperature and fluid fly ash when added to cements are addressed. The theoretical knowledge was used to design subsequent experiments. The conclusion of the theoretical part of the work deals with pozzolans. The main content of the experimental part was the analysis of raw materials and subsequent analysis of the mechanical properties of the prepared mixtures. The experiments were designed in accordance with valid standards.
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Porosity during welding aluminous alloys
Hájková, Alena ; Daněk, Ladislav (referee) ; Sigmund, Marian (advisor)
This thesis deals with the problem of occurrence of porosity in aluminous alloys and the methods of their repair in the company IFE. Theoretical part is aimed on the current state of porosity and the ways in which the be pores can be repaired. Used technologies of repairs are TIG welding and cementing. The practical part consists of experiment in which is used a method of cementing on specific part.
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Utilization of waste glass in cement composites
Gottwaldová, Aneta ; Dufka, Amos (referee) ; Bodnárová, Lenka (advisor)
Bachelor thesis deals with the processing of waste glass in cement composites. Bachelor thesis includes a search theoretical and experimental part. Specifically, it was verified by fluorescent waste glass and glass screen at a dose of 5, 10, 15 and 20 weight % of a batch of cement. Properties of composites were examined after 7, 28, 56 and 90 days. We monitored TG analysis and XRD analysis of cement composites with waste glass.
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Cement worm conveyor
Fránek, Martin ; Malášek, Jiří (referee) ; Škopán, Miroslav (advisor)
This bachelor project contains of a detail and design of a sloping cement worm conveyor. The project consists of technical specifications and drawing documentation. The technical specifications deal with basic design, calculations and stress analysis. The drawing documentation reflects the main assemble conveyor, a bill of material and welding assembly of the spiral worm.
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