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Influence of multiple cyclic loading on the selected parameters of lightweight concrete
Alexa, Martin ; Misák, Petr (referee) ; Kocáb, Dalibor (advisor)
The diploma thesis deals with the observation of the values of selected parameters (especially the static modulus of elasticity) of light-weight concrete in compression before and after multiple cyclic loading. The deformation of test specimens during multiple cyclic loading were measured with resistive strain gauges. Test specimens (cylinders with a diameter of 150 mm and height of a 300 mm) were cyclically loaded and up to 4 500 loading cycles were performed. The aim of this thesis is assessment changes in the values of static modulus of elasticity depending on the number of loading cycles.
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Initiation of stable crack propagation of selected building composites
Majtánová, Romana Viktória ; Veselý, Václav (referee) ; Keršner, Zbyněk (advisor)
The purpose of my bachelor’s thesis is study of the effects of fibres in normal-weight concrete and light-weight concrete. Specimens were prepared from concrete with polypropylene fibres FORTA FERRO of three different lengths – 19, 38 and 54 mm – and also reference concrete (without fibres) was prepared. This thesis contains gradual evaluation of fracture tests on specimens from mentioned materials. The used fracture test was a three–point bending fracture test on beams with a central notch. From the measured load–deflection in the middle of span and load–crack mouth opening displacement diagrams were determined values of modulus of elasticity, unstable fracture toughness, initiation part of fracture toughness and also load level for beginning of stable crack propagation composites. For determination was used „double–K“ fracture model. For illustration is described evaluation using the effective crack model.
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Lightweight concrete with reinforcement
Plochý, Ondřej ; Hubertová,, Michala (referee) ; Hela, Rudolf (advisor)
This bachelor thesis summarizes the current knowledge regarding to the design and properties of lightweight concrete and concrete with reinforcement. Also deals with research of lightweight aggregate concrete with Liapor and its interaction with dispersed steel fibers. The work examined recipes of volume classes D1,6 and D1,8 and strength classes SFRLC 20/22 and SFRLC 25/28. Recipes are monitored by physical-mechanical and rheological properties.
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Influence of multiple cyclic loading on the selected parameters of lightweight concrete
Alexa, Martin ; Misák, Petr (referee) ; Kocáb, Dalibor (advisor)
The diploma thesis deals with the observation of the values of selected parameters (especially the static modulus of elasticity) of light-weight concrete in compression before and after multiple cyclic loading. The deformation of test specimens during multiple cyclic loading were measured with resistive strain gauges. Test specimens (cylinders with a diameter of 150 mm and height of a 300 mm) were cyclically loaded and up to 4 500 loading cycles were performed. The aim of this thesis is assessment changes in the values of static modulus of elasticity depending on the number of loading cycles.
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Lightweight concrete with reinforcement
Plochý, Ondřej ; Hubertová,, Michala (referee) ; Hela, Rudolf (advisor)
This bachelor thesis summarizes the current knowledge regarding to the design and properties of lightweight concrete and concrete with reinforcement. Also deals with research of lightweight aggregate concrete with Liapor and its interaction with dispersed steel fibers. The work examined recipes of volume classes D1,6 and D1,8 and strength classes SFRLC 20/22 and SFRLC 25/28. Recipes are monitored by physical-mechanical and rheological properties.
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Initiation of stable crack propagation of selected building composites
Majtánová, Romana Viktória ; Veselý, Václav (referee) ; Keršner, Zbyněk (advisor)
The purpose of my bachelor’s thesis is study of the effects of fibres in normal-weight concrete and light-weight concrete. Specimens were prepared from concrete with polypropylene fibres FORTA FERRO of three different lengths – 19, 38 and 54 mm – and also reference concrete (without fibres) was prepared. This thesis contains gradual evaluation of fracture tests on specimens from mentioned materials. The used fracture test was a three–point bending fracture test on beams with a central notch. From the measured load–deflection in the middle of span and load–crack mouth opening displacement diagrams were determined values of modulus of elasticity, unstable fracture toughness, initiation part of fracture toughness and also load level for beginning of stable crack propagation composites. For determination was used „double–K“ fracture model. For illustration is described evaluation using the effective crack model.
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