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Study of properties of polymer-modified cementitious adhesive material during shear stresses
Powetz, Dominik ; Nováček,, Jaroslav (referee) ; Žižková, Nikol (advisor)
This bachelor thesis deals with the study of the properties of the polymer modified cementitious tile adhesives during shear stress. In the theoretical part of this thesis is described the influence of absorption of the tile and the content of polymer powder on tensile adhesion and shear strength. After that, the review of known methods for determining the shear strength of adhesives and mortars was done. In the last step of the theoretical part, this bachelor thesis is focused on the most common building defects and failures that occur during the tiling and their subsequent use in the construction of wall cladding elements and ceramic floor tiles. The practical part of the bachelor thesis is focused on the design and testing of an alternative method for the determination of shear strength of bonding, with the effort to achieve the simplest and the most economical option for testing (easy sample preparation, low demands on instrumentation) with the possibility of replacing the known method DIN 18156-3 for testing shear strength of cementitious tile adhesives.
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Effect of Interlayer Composition on Bond Strength between FRC Framework and Composite Veneer
Ibarra, Jonatanh José ; Pavelka,, Vladimír (referee) ; Poláček, Petr (advisor)
Hlavním cílem této práce je studium aktuálního problému adheze mezi kompozitními materiály, a určení vlivu složení mezivrstvy v pevnosti adhezivního spoje mezi vláknové (FRC) a částicové (PFC) kompozity, používané ve stomatologii. FRC tyčinky byly vytvořené na bázi komerční dimetakrylatové pryskyřice a skleněných S vláken. PFC byl vytvořen ze směsi pryskyřic (bis-GMA a PEGDMA), plněných drceným barnatým sklem. Celkově bylo připraveno a vyzkoušeno 84 vzorků. Vzorky byly rozdělené do pěti hlavních skupin. První skupina byla vytvořena ze série vzorků bez mezivrstvy. Zbylé čtyři skupiny byly rozděleny dle složení mezivrstvy (tloušťky a druhu pryskyřic). Částicové kompozity vzorků se lišily obsahem plniva (0, 10, 40 hm %). FRC tyčinky byly stejné pro všechny vzorky. Univerzální testovací přístroj ZWICK Z010 byl použit k zjištění smykové pevnosti adhezivního spoje všech vzorků. Rastrovací elektronový mikroskop byl použít k pozorování místa porušení. Ze získaných výsledků vyplívá, že s přidáváním mezivrstvy mezi vláknovým a částicovým narůstá smyková pevnost spoje. Důležitost těchto výsledků je způsobená tím, že v posledních letech použití těchto materiálů ve stomatologii narůstá a adheze zůstává jeden z hlavních problémů při klinické praxi.
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Bonding in the automotive industry
Krejčí, Adam ; Hanáčková, Pavla (referee) ; Kubíček, Jaroslav (advisor)
The thesis presents a literature study of adhesive bonding technology. The work deals with the advantages and disadvantages of adhesive bonding, design of adhesive joints, technological processes of adhesive bonding and the division of adhesives. The thesis also discusses various materials used for the construction of car bodywork and their properties. The main focus of the work is on the use of adhesive bonding in the car industry, comparing traditional and modern technology used for the construction of bus bodywork. In the experimental part of the thesis, the aim is to reveal the influence of surface treatment on the resulting shear strength when employing metal to metal bonding.
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Gluing of FDM 3d printed parts from PLA
Šlimar, Filip ; Slaný, Martin (referee) ; Zemčík, Oskar (advisor)
The thesis deals with the theory of 3D printing, materials for printing and bonding. It focuses on FDM printing and PLA material. It also compares gluing with other methods and deals with the distribution of adhesives, the gluing procedure and tests of glued joints. The work, based on literature studies, proposes an experiment to evaluate selected adhesives. The practical part contains a description, results and evaluation of the experiment. The evaluation of adhesives is based on tensile and shear strength.
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Asphalt layers with reinforcing glass-fiber geogrids
Sachr, Jiří ; Bohuš,, Štěpán (referee) ; Dašek, Ondřej (advisor)
This diploma thesis deals with the use of glass fiber geogrids and geocomposites in road construction. The reinforcement elements are inserted between the wearing and binder asphalt layer. This diploma thesis summarizes the knowledge connected with reinforcing of asphalt roads using glass fiber. It examines the effect of reinforcing fiberglass elements on the resistance of asphalt layers loaded with traffic. At the same time, it deals with the application of a various amount of tack coat and subsequent behavior of the asphalt layers. In this work, laboratory tests of bond strength between layers on cores and four-point bending were performed.
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Experimental comparison of shear properties of FRP measured by ASTM methods
Ponížil, Tomáš ; Mališ, Michal (referee) ; Urík, Tomáš (advisor)
Přesné určení konstitutivních smykových závislostí napětí na deformacích je základem pro pochopení chování anizotropního kompozitního materiálu. Bylo vyvinuto mnoho zkoušek smykových vlastností kompozitních materiálu. Jelikož vyvolání čisté smykové napjatosti je složité, tento stav je vyvolán pouze některými z nich. V této práci je ověřeno použití systému Aramis k vyhodnocení průběhu smykového přetvoření a následnému výpočtu konstitutivních smykových vlastností při provedení jednoduché zkoušky ohybem krátkého nosníku. Tyto výsledky jsou dále porovnány se zkouškou podle Nicolae Iosipesca.
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New directions for waterproofing of underground transport
Čech, Tomáš ; Čížek, Luboš (referee) ; Šťastník, Stanislav (advisor)
This diploma thesis focuses on the implementation of waterproofing of underground constructions using an LLDPE membrane hinged on anchors. In the future, this method will replace the commonly used waterproofing system in Scandinavia with extruded polyethylene foam. This method of tunnel construction and waterproofing is compared with the NRTM method, often used in Central Europe. The thesis describes the installation of a waterproofing system, especially materials, accessories, welding devices and auxiliary installation equipment. The main focus of the thesis is to verify the reliability of the individual types of welds and to assess the waterproofing system in terms of implementation and environmental demands.
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Evaluation of load-deformation characteristics of glued timber using DIC analysis
Šot, Michal ; Vejpustek,, Zdeněk (referee) ; Vaněrek, Jan (advisor)
The work deals with issues of evaluation of the shear properties of timber structural materials, particularly CLT elements. The work contains an overview of extensive research so far presented scientific studies dealing with the characteristic shear properties of wood. In the practical part was carried out the experiment dealing with the failure mode of transverse lamellae of CLT elements that were exposed to shear stress. There were observed individual effects that this may affect the material properties. In the first part of the experiment were performed numerical models using FEM. In the second part, the test specimens were tested in three point bending. Here, attention was paid to the influence of macroscopic properties of wood on the distribution of stress cracks and shear strength, the tests were recorded using DIC system.
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Posouzení využitelnosti vybraných listnatých dřev pro výrobu kompozitu na bázi dřeva
Kašpařík, Matěj
The bachelor thesis deals with the issue of the possibility of replacing spruce wood in the production of OSB with hornbeam and birch wood. The purpose of the thesis is to compare selected physical and mechanical properties of OSB made of these woods with standardized properties of OSB. In the first part, the origin, characteristics and current use of OSB are presented. The second part deals with the material and methodology of all the tests performed. The following properties of the boards were investigated: moisture content, flexural strength and elastic limit, density profile, swelling, delamination and shear strength of the glued joint. In the third part of the paper, the results of the tests and their comparison with the standard requirements for OSB are presented, followed by a summary and discussion.
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