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Influence of inorganic admixtures on shrinkage reduction of alkali activated materials
Šístková, Pavlína ; Koplík, Jan (referee) ; Kalina, Lukáš (advisor)
This bachelor thesis is focused on the influence of inorganic admixtures on shrinkage reduction of alkali activated materials. In the theoretical part the issue of alkali activated materials is explained in detail focusing on the reduction of their shrinkage. Alkali activated system is constituted by alkali activated blast furnace slag. Firstly, the effect of inorganic dashes is monitored such as low calcium fly ash and finely ground limestone. Furthermore, the influence of inorganic additives for reducing shrinkage has been studied, namely magnesium oxide and calcium oxide. The aim of this work is to determinate the mechanical properties and shrinkage of individual alkali activated mixture and then discuss whether there was a reduction of shrinkage and what the effect of added dashes and inorganic admixtures was.
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Development of Grouts for Ceramic Tiles
Coufal, Daniel ; Gazdič, Dominik (referee) ; Fridrichová, Marcela (advisor)
The bachelor thesis deals with the development of grout for filling of wide joints of ceramics tiles. The theoretical part is devoted to individual types of jointing materials, their properties and application. The practical part deals with proposed mixtures with focus on the influence of the filler as ground limestone and his substitution with silica sand and the effect of the subsequent modification of these mixtures by the expansion additive.
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Bridge ower the Opavice river
Tang, Minh Phú ; Russnák, Adam (referee) ; Panáček, Josef (advisor)
The diploma thesis deals with the design of a road bridge on the I/57 expressway over the relocation of the cycle path, the Opavice river and the local road, which involves the relocation of the access to the waterworks. The bridge structure is located in the territory of the town of Krnov. A study of the area's bridges is part of the project and three studies have been prepared. Study A was chosen for detailed processing. It is a continuous box girder bridge with three spans. The superstructure is designed as a monolithic, post-tensioned structure. A sliding girder is being investigated for the structure's construction. Scia Engineer 18.1 is used to do the load effects computation. Only the consequences of vertical load effects have been addressed, with no consideration of horizontal load effects. The structure was evaluated using limit states, taking into account the impact of construction on its design.
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Physical Discretization Modelling of Shrinkage
Bedáň, Jan ; Keršner, Zbyněk (referee) ; Frantík, Petr (advisor)
The aim of this thesis is design and programming of a numerical model of shrinkage of cement composites using physical discretization and solved by parallel processing. Introduction is about the shrinkage of cement composites and explanation of terms, which are included in this thesis. The main part deals with programming of the output model, the procedure of its creation and the results of simulations.
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Latex Modified Cement Composites
Kunc, Michal ; Rovnaníková, Pavla (referee) ; Kuřitka, Ivo (referee) ; Havlica, Jaromír (advisor)
The subject of dissertation is a study of physic-mechanical properties and development of self-leveling polymer-cement composite of the ternary binder system PC-CAC-CS modified with chemical additives and polymeric substances. The dissertation systematically describes a four-step optimalization of the composite considering its key properties. Experimental part has been focused on monitoring the impact of composite components on selected final properties. Basic physico-mechanical, structural properties and its relations (compressive strength, porosity, flow abilities, setting times) have been analyzed for deeper understanding of the effects of individual composite components. Methods which quantify the existence of the newly formed hydration product – ettringite (XRD, SEM with EDS, calorimetry, dilatometry) has been chosen as additional study methods on selected combinations. A working prototype of self-leveling polymer-cement composite was successfully developed based on systematic process and using of testing procedures and measuring methods.
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Design of steel-concrete composite structure of road bridge in Trenčín
Doležal, Tomáš ; Marván, David (referee) ; Nečesal, Petr (advisor)
The aim of diploma thesis was to design alternative of composite road bridge in Trenčín. The bridge beam is designed as continuous with theoretical span of 65 m + 106 m + 65 m. Permanent load, climatic load (uniform and nonuniform temperature variation, windload), shrinkage, differential settlement and traffic load were taken into consideration according to Eurocodes. Technical report, static report, drawings, bill of quantities are included. Computational model for evaluation of internal forces was carried out in SCIA Engineer software.
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Effect of Cement Bypass Dust on Cracking Tendency of Alkali-Activated Slag during Drying
Krejčová, Marie ; Švec, Jiří (referee) ; Bílek, Vlastimil (advisor)
This bachelor thesis deals with the influence of bypass cement dust on cracking of alkali activated slag. Significant shrinkage and cracking prevent greater use of alkali activated slag. The length changes and strength of the mixtures with different amount of bypass cement dust were measured at various curing conditions. In these mixtures, cracks were observed and their amount was evaluated by image analysis. It has been found that the addition of dust can reduce the amount of cracks. Treating the prisms in a humid environment leads to a reduction of cracks, especially during long-term treatment. In order to improve flexural and compressive strength, it is preferable to use dust as a replacement for part of aggregates and not as a partial slag replacement.
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Design of simple engineering structure
Macková, Lucie ; Navrátil,, Jaroslav (referee) ; Klusáček, Ladislav (advisor)
Bachelor’s thesis processes methodology of calculating the deflection according to norm EN 1992-1. First of all it deals with the theory necessary to understand the whole process and explanation of each step. Next learned lessons are applied in the model calculation of deflections, which is performed at 3 beam elements of different construction heights. The resulting values are compared to point out changes in the final deflection according to different dimensions of the structure.
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Volume changes of concrete based on reactive powder components and possibilities of their regulation with chemical admixtures
Hlaváček, Jaroslav ; Kalinová, Helena (referee) ; Opravil, Tomáš (advisor)
Very high strength of RPC allows them to an unusual extreme possibilities of their applications. Volume change (shrinkage) negatively affects their relatively broad range of applications, particularly in applications which are used for filling tubes or other components. In today's advanced time with plenty of chemical ingredients and additives on the market (such as the expansion component) could be a side effect of this largely eliminated, or removed entirely. Only some components of the expansion will be appropriate for RPC cements. This reaserch investigates the expansion of ingredients on the basis of sulfates and monitors not only volume changes, but also the strength characteristics and tolerability of the tested anchors tested with a matrix component of the expansion.
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Experimental and Numerical Analysis of the Volume Changes of Fine-grained Concretes
Odstrčil, Štěpán ; Frantík, Petr (referee) ; Kucharczyková, Barbara (advisor)
This diploma thesis deals with the experimental and numerical analysis of volume changes of fine-grained concrete. Experiments were carried out, measuring both the length changes as well as the mass losses and the internal temperature of the test specimens made from fine-grained concrete. The measurements were divided into two parts (phases). The first phase took approx. 72 hours. The second phase was focused on the long-term measurements and will be completed after stabilization of the mass losses and length changes. In the diploma thesis, the first phase of measurement was elaborated in detail, both in terms of experimental and numerical analysis. In addition, a C # .NET program was created to facilitate the processing of raw measurement data from the data logger. Finally, a comparative calculation was performed according to the model B4, where the result of the calculation was compared with the results of the experiment.
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