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Analysis of concrete pipe using fracture-mechanical models
Bejček, Michal ; Šimonová, Hana (referee) ; Řoutil, Ladislav (advisor)
This bachelor thesis is focused on plain concrete pipe analysis in consideration of design problems. The introduction describes concrete pipe including imposed standards. The next part contains a summary of the calculation methods used nowadays. The thesis explores whether the fracture-mechanical calculation is sufficiently apt and therefore can be applied for the pipeline design. A number of pipe profile models was constructed and analysed for this purpose. The calculation based on the finite element method with applied crack band model was executed by software ATENA 2D. The crushing strength, which is compared to real tests data, is determined in models with altered input figures. The thesis also studies the negative effects on carrying capacity including material degradation.
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Modeling of fracture process in quasi-brittle materials
Klon, Jiří ; Eliáš, Jan (referee) ; Veselý, Václav (advisor)
This work is focused on the evaluation of the selected fracture parameters of quasi-brittle material, especially concrete, and an assessment of their dependence on the size and shape of the fracture process zone developing at the tip of the macroscopic crack during fracture. For this purpose, experimentally obtained loading diagrams published in the scientific literature have been utilized. These diagrams have been processed into a form enabling creation and calibration of numerical models of these tests in the ATENA FEM program. The results obtained from simulations of the three-point bending tests on beams of four sizes, with three notches lengths, using the created numerical models were used for determination of fracture parameters of concrete. Results of the work consist of the determined values of the specific energy dissipated for creation of new surfaces of the effective crack and an estimation of the specific energy dissipated in the volume of the fracture process zone, which exhibits specific parameters for each beam size and notch length.
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Modeling of fracture process in quasi-brittle materials
Klon, Jiří ; Eliáš, Jan (referee) ; Veselý, Václav (advisor)
This work is focused on the evaluation of the selected fracture parameters of quasi-brittle material, especially concrete, and an assessment of their dependence on the size and shape of the fracture process zone developing at the tip of the macroscopic crack during fracture. For this purpose, experimentally obtained loading diagrams published in the scientific literature have been utilized. These diagrams have been processed into a form enabling creation and calibration of numerical models of these tests in the ATENA FEM program. The results obtained from simulations of the three-point bending tests on beams of four sizes, with three notches lengths, using the created numerical models were used for determination of fracture parameters of concrete. Results of the work consist of the determined values of the specific energy dissipated for creation of new surfaces of the effective crack and an estimation of the specific energy dissipated in the volume of the fracture process zone, which exhibits specific parameters for each beam size and notch length.
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Analysis of concrete pipe using fracture-mechanical models
Bejček, Michal ; Šimonová, Hana (referee) ; Řoutil, Ladislav (advisor)
This bachelor thesis is focused on plain concrete pipe analysis in consideration of design problems. The introduction describes concrete pipe including imposed standards. The next part contains a summary of the calculation methods used nowadays. The thesis explores whether the fracture-mechanical calculation is sufficiently apt and therefore can be applied for the pipeline design. A number of pipe profile models was constructed and analysed for this purpose. The calculation based on the finite element method with applied crack band model was executed by software ATENA 2D. The crushing strength, which is compared to real tests data, is determined in models with altered input figures. The thesis also studies the negative effects on carrying capacity including material degradation.
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