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Long-term tests for examination of surface treatments in various adverse environments simulating real effects
Hudečková, Petra ; Vacula, Miroslav (referee) ; Bydžovský, Jiří (advisor)
Cement bonded particleboards contain organic base and as they are set outside, extreme weather condition, such as frost, chemical defrosting substances or sulphates, cause their degradation. The presence of the organic base in the matrix of the material could be the reason why there is higher probability of degrading when compared with materials containing an inorganic base. It could be partially eliminated by an appropriate surface modification of the slab, which main goal is to weaken the impact of an aggressive environment and to extend the lifespan of the board. On the other hand, the surface modifications based on a polymer base are prone to degrade because of other unfavourable conditions such as UV radiation when compared with the cement bonded particleboard. The classification of the surface modifications and the way of their degradation caused by the aggressive environment in real applications are presented in the theoretical part of the thesis. In the experimental part, appropriate methodical ways of testing the resistance of cement bonded particleboard’s coating system were chosen. Then, the testing and comparing of the physical, mechanical and aesthetic properties of different types of coatings were done. Moreover, a spectrophotometric analysis of the colour shade changes for the different aggressive environment were carried out. Furthermore, microstructures of chosen surface modifications were assessed by using an optical and an electron microscope.
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Optimisation of cement-bonded particleboard matrix composition by using alternative raw material sources
Roháček, Lukáš ; Vacula, Miroslav (referee) ; Bydžovský, Jiří (advisor)
The diploma thesis deals with possibility of utilization raw materials from alternative sources for production of cement-bonded particleboards. In theoretical part the possibilities of modifying composition of cement-bonded slabs with emphasis on their matrix are discussed in detail. On basis of the findings and their evaluation, waste from the formatting of cement-bonded particleboards, micronized limestone, heat sink and high temperature fly ash were selected to the composition modification. The mentioned raw materials were analyzed and subsequently tested as substitutes for the matrix of cement-bonded particleboards in the experimental part. The properties of the proposed materials were tested even in the longer term, including the microstructure.
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Leisure Time Centre Brno
Kubačka, Jan ; Teplý, Vladimír (referee) ; Odvárka, Antonín (advisor) ; Štěpánek, Ladislav (advisor)
The objective of this project was to design a complex for leisure time activities. This locality, which is slightly declining to the south, is situated in the city of Brno, in the city district of Nový Lískovec, in the current park between Chironova and Plachty streets. After considering the concept, the object – ordinary square – was easily situated in the center of all pedestrian communications. There was created a small square around this point,which is surrounded by four non-rectangular buildings with unique construction system. Whole set of structures seems to be compact from outter park view, so a visitor will identify the complex division only inside. There are four entrances to the central square in the directions of the initial communications. The complex is structured into four functional units. Through sport, gastronomy, cultural hall for up to commercial spaces. Some of the four objects were designed as two-story. Around the whole square there is a gallery, which provides the acces to the services on the second floor. The gallery is connected to the ground by three vertical communications.
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Surface treatment for resistance improve of board materials with cement matrix and an organic filler
Zrza, Ondřej ; Vacula, Miroslav (referee) ; Bydžovský, Jiří (advisor)
As all materials used for exterior construction, cement-bonded particleboards also subject to climatic effects, such as frost, chemicals (eg. sulphates) or UV rays. Degradation of theese effects is slightly increased by organic base. Increased susceptibility can be eliminated by a effective coating, which reduces direct contact with aggresive influences on the board and provides longer durability. Theoratical part of this thesis analyzes different types of negatice influences and their effect on durability. Practical part contains selection of specific types of coating and assessment of their mechanical and aesthetic properties including spectrophotometric analysis of color change for each degradation effect.
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Boards with alkali activated binder filled with wood chips
Gajdušková, Patricie ; Vacula, Miroslav (referee) ; Bydžovský, Jiří (advisor)
For the production of cement chipboards, cement is used as a binder which is an ecological burden for our planet. This diploma thesis deals with research into the possibility of replacing it with other alternative materials, especially those that are created as a by-product of other production. The focus is primarily on slag, heating plant slag or brick dust. The theoretical part deals with the previous studies and theoretical knowledge of alkaline-activated matrices which are supplemented with an organic binder such as wood chips which are used to reinforce the boards. The practical part deals with the above-mentioned alternative materials which are tested for the design of recipes for modified boards made of alkali-activated binder reinforced with chips. These modified recipes are subsequently subjected to physical-mechanical tests such as bending strength, modulus of elasticity and other monitored parameters of the boards. Selected board variants were analysed in terms of mineralogical composition and microstructure.
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Optimisation of cement-bonded particleboard matrix composition by using alternative raw material sources
Roháček, Lukáš ; Vacula, Miroslav (referee) ; Bydžovský, Jiří (advisor)
The diploma thesis deals with possibility of utilization raw materials from alternative sources for production of cement-bonded particleboards. In theoretical part the possibilities of modifying composition of cement-bonded slabs with emphasis on their matrix are discussed in detail. On basis of the findings and their evaluation, waste from the formatting of cement-bonded particleboards, micronized limestone, heat sink and high temperature fly ash were selected to the composition modification. The mentioned raw materials were analyzed and subsequently tested as substitutes for the matrix of cement-bonded particleboards in the experimental part. The properties of the proposed materials were tested even in the longer term, including the microstructure.
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Long-term tests for examination of surface treatments in various adverse environments simulating real effects
Hudečková, Petra ; Vacula, Miroslav (referee) ; Bydžovský, Jiří (advisor)
Cement bonded particleboards contain organic base and as they are set outside, extreme weather condition, such as frost, chemical defrosting substances or sulphates, cause their degradation. The presence of the organic base in the matrix of the material could be the reason why there is higher probability of degrading when compared with materials containing an inorganic base. It could be partially eliminated by an appropriate surface modification of the slab, which main goal is to weaken the impact of an aggressive environment and to extend the lifespan of the board. On the other hand, the surface modifications based on a polymer base are prone to degrade because of other unfavourable conditions such as UV radiation when compared with the cement bonded particleboard. The classification of the surface modifications and the way of their degradation caused by the aggressive environment in real applications are presented in the theoretical part of the thesis. In the experimental part, appropriate methodical ways of testing the resistance of cement bonded particleboard’s coating system were chosen. Then, the testing and comparing of the physical, mechanical and aesthetic properties of different types of coatings were done. Moreover, a spectrophotometric analysis of the colour shade changes for the different aggressive environment were carried out. Furthermore, microstructures of chosen surface modifications were assessed by using an optical and an electron microscope.
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Surface treatment for resistance improve of board materials with cement matrix and an organic filler
Zrza, Ondřej ; Vacula, Miroslav (referee) ; Bydžovský, Jiří (advisor)
As all materials used for exterior construction, cement-bonded particleboards also subject to climatic effects, such as frost, chemicals (eg. sulphates) or UV rays. Degradation of theese effects is slightly increased by organic base. Increased susceptibility can be eliminated by a effective coating, which reduces direct contact with aggresive influences on the board and provides longer durability. Theoratical part of this thesis analyzes different types of negatice influences and their effect on durability. Practical part contains selection of specific types of coating and assessment of their mechanical and aesthetic properties including spectrophotometric analysis of color change for each degradation effect.
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