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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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Development of concrete with high fly ash content and verification of durability in various environments
Ambruz, Pavel ; Voves, Jiří (referee) ; Hela, Rudolf (advisor)
This thesis contains two main parts: theoretical and experimental. The theoretical part deals with summarization knowledge of high-volume fly ash (HVFA) concretes. Among others, there are mentioned processes of producing of fly ash, characteristic features and resistance to aggressive environments of HVFA concretes. The theoretical part ends with a suitable example of practical application. In the practical part were tested properties of nine different mixtures containing 40%, 50% and 60% replacement by weight of the cement by fly ash. They were compared with the reference mixtures without fly ash addition. The main endpoints were long-term compressive strength, resistance to aggressive environments, the influence of fly ash on consistency, hydratation temperatures, water absorption and volume changes.
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The utilization of the asphalt and concrete recycled materials to roads
Žďára, Zbyněk ; Šperka, Pavel (referee) ; Stehlík, Dušan (advisor)
This diploma thesis is divided into two parts, theoretical and practical. The is a review om the topic of recycled asphalt pavement and recycled concrete and their possible use in road construction in the theoretical part. The individual chapters deal with describing these materials, their production, and their use in construction layers of pavements. In the next chapters the attention is also paid to their problematic features and foreign experience using these materials in pavements. In the practical part, laboratory samples of recycled asphalt pavement and recycled concrete and their mixtures with cement are tested. The main purpose is to verify the applications of these mixtures of recycled asphalt pavement and recycled concrete in the bonded base layers of the pavement. Another purpose is to compare how these mixtures individual properties with different proportions of both components and different amounts of cement will be different. In the end, the two mixtures with the best properties was selected and the modulus of elasticity was experimentally determined for the possibility of replacing the currently used base layers and the economic evaluation of this design was made.
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The Influence of different Types of Fiber-reinforcement on the Behavior of Concrete Slabs
Wünsche, Dominik ; Žítt, Petr (referee) ; Kocáb, Dalibor (advisor)
The bachelor‘s thesis deals with the issue of concrete, specifically self-compacting concrete, fiber concrete and other types of concrete used. The work consists of two parts, the theoretical one, which will deal with the properties of the concrete. It describes the individual test methods used in the practical part. The test methods are the ultrasonic pulse method, the resonance method, the static modulus of elasticity, the compressive strength, and especially flexural strength. The second part is a practical part, which is processed by an experiment. In the experimental part, it will be mainly about carrying out tests of self-compacting concrete slabs and concrete with the addition of steel fibers. Subsequently, selected characteristics of concrete are determined and the whole experiment is evaluated.
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The development of high-strength concrete with a high content of el. fly ash
Roubal, David ; Ťažký, Tomáš (referee) ; Hela, Rudolf (advisor)
This diploma thesis deals with the study of high-strength, high-volume fly ash concrete. The theoretical part of this thesis focuses on the detailed characteristic and main principles of high-strength concrete, high-volume fly ash concrete. In addition, according to the findings, the technology of high-strength and high-volume fly ash concrete, including principles of high strength, has been described. On the basis of the findings, high-strength, high-volume fly ash concrete for specific compressive strengths has been designed and created in the experimental section. These concretes were then subjected to a number of tests.
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Comparison of selected parameters of tensile strength of concrete
Rozsypalová, Iva ; Žítt, Petr (referee) ; Daněk, Petr (advisor)
The thesis deals with a comparison of the selected strength tension properties of the hardened concrete and finding relationships between them. This is essentially a simple tensile strength, tensile flexural strength and tensile splitting strength. The text describe the testing procedures to determine the tensile strength of concrete. Furthermore, there are presented the results of testing on different types of concrete (plain concrete, lightweight concrete, steel-fiber concrete, polymer-fibre concrete and high strength concrete). The conclusion deals with the derivation of dependancy between concrete strengths and comparing the values obtained from the available relations with the results of the tests.
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Suitability of vitrified lignite bottom ash for composite cements.
Bayer, Petr ; Krátký, Josef (referee) ; Wolter, Albrecht (advisor)
Předložená magisterská práce se zabývá možným použitím vitrifikovaného lignitového lóžového popele jako náhrada slinku v kompozitních cementech. Byly zkoumány vlivy přidaného vitrifikovaného lóžového popele, jeho jemnosti, alkalických roztoků a jejich koncentrací. Byly připraveny kompozitní cementy v souladu s normou DIN EN 197 – 1. V těchto cementech bylo nahrazeno 30 % slinku vitrifikovaným lóžovým popelem. Konkrétně byly připraveny kompozitní cementy s vitrifikovaným lóžovým popelem o jemnosti 5549 cm2/g a 8397 cm2/g. Dále byly přidány alkalické roztoky hydroxidů a síranů vždy o dvou různých koncentracích, za účelem stimulace pucolánové a/nebo geopolymerní reakce. Mechanické vlastnosti připravených vzorků byly charakterizovány mechanickým testováním na prizmách s rozměry 40×40×160 mm, jak je specifikováno v normě DIN EN 196 – 1. Byla provedena nedestruktivní měření dynamického elastického modulu a destruktivní testovaní na pevnosti v tlaku a v ohybu. Distribuce velikosti částic a chemická analýza vstupních materiálů byla vykonána pomocí laserové granulometrie a rentgenové fluorescence. U zatvrdlých kompozitů bylo dále zkoumáno po 2 a 28 dnech hydratace fázové složení s využitím metody rentgenové difrakce a mikrostruktura s využitím skenovací elektronové mikroskopie. Výsledky ukázaly, že mechanické vlastnosti jsou nezávislé na množství přidaných alkálií stejně jako na jemnosti přidaného vitrifikovaného lóžového popele. Nicméně, znatelně nižší mechanické pevnosti byly pozorovány pro vzorky, které byly aktivovány hydroxidy, pravděpodobně kvůli brzké tvorbě silikátového hydrogelu. Vzorky aktivované sírany nedosáhly pevností jako referenční malta.
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Modification of silicate materials for floors
Šlechtický, Luboš ; Ing. Miroslav Šťenko, Ph.D., LB Cemix (referee) ; Šťastník, Stanislav (advisor)
The thesis is devoted to the issue of flooring materials, cement and plaster. In the first part are discussed general properties and general requirements for flooring, as well as presents the most important properties of selected flooring materials. The work is dedicated to the modulus of elasticity, adhesion to the substrate and strength parameters of the tested materials. It also evaluates the effects of redispersible polymer powders in silicate compositions intended for floors.
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The study of the influence of the composition of the lightweight fiber concrete physical and mechanical properties
Šindelek, David ; Bodnárová, Lenka (referee) ; Hela, Rudolf (advisor)
This bachelor thesis deals with a study of light construction concrete with an addition of steel fibre which monitors its impact of the physical mechanical properties. The work is divided into two parts, theoretical and practical. The theoretical part is focused on characteristics and a design of light concrete within the class 35MPa and over with the density within the class of D1,8. Furthermore, it focuses on the increase of toughness of cementitious composites with the form of application of steel fibre in different doses and lengths. In the practical part, formulas of two strength classes 35/38 D 1,8 and 45/50 D1,8 were designed with the help of the steel fibre Krampeharex in doses of 25 and30 kg/m3, and where there were both its impact of the working diagram as well as the compressive strength monitored for the duration of twenty-eight days
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