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The frost susceptibility of unbound mixtures to pavements
Surá, Kateřina ; Zajíček, Jan (referee) ; Stehlík, Dušan (advisor)
The thesis is focused on the analysis of the theoretical part of the unbound mixtures, their implementation and compliance. Further deals with determining the extent frost susceptibility direct and indirect method in the Czech Republic and the Member States of the European Union. The practical part is focused on the performance of tests on selected samples of unbound mixtures for which was gradually increased the content of fine particles and that direct and indirect method of determining the rate of frost susceptibility and also the evaluation of direct methods of particular customized way, which does not impose the appropriate standard. At the conclusion of the work is carried out an evaluation of the samples and comparison of the different methods with each other.
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The frost susceptibility of soils and materials for subgrade of pavements
Puda, Adam ; Pácha, Petr (referee) ; Stehlík, Dušan (advisor)
The bachelor thesis deals with the theoretical part of the deformation caused by frost action, but primarily frost heave, their gradual development and factors affecting their final formation. Furthermore, different ways of measuring the frost susceptibility in the Czech Republic and their comparison. Introduction to the different methods of measuring frost susceptibility in selected countries within the European Union. The practical part is focused on the process of frost heave samples with and without thermal insulation material.
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Assessment of the effect of origin and the fraction of coarse aggregate for flexibility and durability of structural concrete
Hanuš, Petr ; Žalud, Oldřich (referee) ; Vymazal, Tomáš (advisor)
The bachelor thesis deals with influence of origin and fraction of rough aggregate on the durability and elasticity of structural concrete. As a criterion of durability, the frost resistance of concrete is monitored. In the theoretical part describes the types of aggregates, which are used in structural concretes. In addition, test methods are described to determine the elasticity and durability of concrete according to the test standards valid in the czech republic. In the experimental part of the thesis, seven concretes of the same consistency and strength were designed and mixed, which differed using different types of coarse aggregate. A change in elasticity during freezing cycles was observed
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Testing of bricks intended for the repair of monuments
Lezová, Lívia ; Anton, Ondřej (referee) ; Cikrle, Petr (advisor)
The bachelor thesis is focused on methods of testing bricks, which will use to classify historic bricks into groups on usable, usable in extreme conditions, usable in limited extent and unusable for restoration of monuments or for construct new constructions. In the theoretical part, there is describe of historical development of solid fired bricks in Central Europe and an overview of methods for testing bricks, including a description of an accomplishments and their evaluation. In the practical part, there are methods applied to three visually different sets of bricks taken from 19th century construction.
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Verification of the usability ultrasonic pulse method for the assessing of frost resistance of concrete bricks
Kašparová, Jana ; Hubáček, Adam (referee) ; Brožovský, Jiří (advisor)
Purpose of Bachelor thesis is to verify use of the utrasonic impulsive method to determine frost resistence of the concrete. Theoretical part disscusses about basic characteristic of a vibropressed concrete, description of a causes of frost and defrosting on the concrete. As well further factor simple menting frost resistance are reviewed. Summary is followed with standard requirements forwall concrete elements, trial proceduresfor non destructive and destructive methods for concrete and other construction materials and thein evaluation systems. Second part of Bachelor thesis is dedicated to analyse and evaluate results and relationship of trials used for testing of a concrete brick in frost resistence with use of cyclic freezing and use of a trial non destrucive ultrasonic impulsive method as well destructive mode.
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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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Mortar with alkali-activated matrix
Černá, Hana ; Hela, Rudolf (referee) ; Bodnárová, Lenka (advisor)
The thesis addresses the issue of alkali-activated materials and their manufacturing components. In the theoretical part the description of such materials is provided and the requirements for source materials are defined. The theoretical part further addresses the resistance of alkali-activated materials and their lifespan - namely sulphate resistance, chloride resistance, acid resistance, frost resistance, porosity, carbonation, resistance, abrasion resistance and heat resistance. The experimental part of the thesis focuses on compounding four different mixtures of alkali-activated materials. In the loosened stage, the weight was measured. In the hardened stage the weight was measured as well as the tensile strength when bending, the strength under pressure applied, heat resistance, water and defrosting chemicals resistance and formation of cracks.
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Options of determining the frost resistance of concrete in a structure
Jindrová, Barbora ; Vymazal, Tomáš (referee) ; Kocáb, Dalibor (advisor)
The diploma thesis deals with different methods of determining levels of degradation of concrete due to freezing, also considering the options of freeze thaw resistance determination in structure. At first the properties of concrete and possible mechanisms of concrete degradation are described – mainly the effects of freezing water in the inner structure and of the combination of freezing water and de-icing chemicals on the surface. Principle and properties of air-entrained concrete are also mentioned. An overview of the approaches that current standards use to determine the freeze-thaw resistance of concrete is listed, followed by description of the tests that are used on air-entrained concrete specimens in the main part of the thesis. A portion of the test specimens was made in moulds while the rest was obtained from structure (concrete block). The non-destructive tests used are evaluated in several different ways and their results are compared with the destructive tests. Comparison and evaluation of different approaches used to determine the freeze-thaw resistence of concrete are the main outcome of this thesis.
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