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Back analysis of embankment dam and prediction of its behaviour during accidental design situations
Krajčovič, Ján ; Říha, Jaromír (referee) ; Chalmovský, Juraj (advisor)
Diplomová práce představuje vytvoření softwarového 2D MKP modelu přehrady Slezská Harta v České Republice za pomoci softwaru PLAXIS 2D. V úvodu práce je analýza vodní nádrže, vytvořené jako zásobárna vody a protipovodňové dílo. Analýza sleduje geomorfologii, geologii, konstrukci tělesa hráze, použité materiály a metody, a stávající monitorovací zařízení. Pro pochopení tvorby 2D MKP modelu jsou předloženy a definované metody použitých analýz - metoda konečných prvků, analýza prosakování, materiálové modely, citlivostná analýza. Následně byla definována tvorba struktury modelu - určení posloupnosti použitých analýz, definování vstupních dat a mezních podmínek a tvorba kalibračního segmentu. V závěrečné části práce je analýza dosažených výstupů rozsáhlého testování modelu, jejich korelace s reálnými naměřenými hodnotami a celkové shrnutí přínosu vytvořeného modelu pro jeho využití při předpovídání chování přehrady v extrémních případech.
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Design of excavation for reconstruction of shopping centre
Červenka, Jan ; Miča, Lumír (referee) ; Chalmovský, Juraj (advisor)
The thesis is divided into three parts. In the first one it deals with the design and the assessment of the once-anchored soldier pile wall, which provides an excavation for the reconstruction of the shopping centre Prior in Zlín. The retaining structure is designed according to the limit state method, using the GEO5 software and the Excel spreadsheet editor. In the second part, the thesis deals with the price comparison of the classic version of the soldier pile wall with soldier pile, IPN profiles, with over one-pole anchorage with the help of the buckle, with the variant with larger spread, where the soldier pile from the pair of UPN profiles are adapted for anchoring. The third part solves the problem of the distribution of a lateral ground pressures along the length of the soldier pile wall. For comparison with the empirical methods of design of lagging, the results of normal pressure from the mathematical model, solved by the numerical analysis, the finite element method, were used in the Plaxis 3D program. Hardening soil model was used as the material model.
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Comparison of two alternatives of deep excavation design
Krejzar, Vojtěch ; Miča, Lumír (referee) ; Chalmovský, Juraj (advisor)
The thesis focuses on numerical modeling of a 30 m deep excavation using the finite element method (FEM). The excavation is situated in Luzern, Switzerland. The subsoil is formed by inclined sandstone or siltstone layers; one of them tends to form a dangerous slip surface. The bachelor’s thesis compares 2 alternatives: Alternative A represents a combination of an anchored pile wall and sprayed concrete in the lower part of the excavation, Alternative B represents a full height anchored pile wall. The thesis comprises of the description of modeling, determination of material parameters and structural members’ inputs, defines calculation phases and predicts the structure deformations. The mathematical model is created using PLAXIS 2D software.
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Prediction of foundation settlement of high-rise building using the finite element method
Červenka, Jan ; Dobrovolský, Ján (referee) ; Chalmovský, Juraj (advisor)
The focus of this thesis is to deal with reverse engineering of high-rise building settlements. This is modeled via the finite element method performed in the Plaxis 3D program. In the first part of this thesis, a calibration of input parameters of an appropriate material model – Hardening soil – is conducted. This calibration is a result of oedometric test data which were obtained within a geotechnical survey. An influence of soils over consolidation affecting calibration and the material model choice is described. Final values of reference stiffness parameters are used in a mathematical model of the focused area. This model is created for one half of the high-rise building plan, including vestibule. The high-rise building is founded in a foundation pit. The foundations of this building consist of raft foundation and piles of jet grouting. In the model, there are also changes in pore pressure during an excavation of foundation pit included. The functional model is used for parametric analyses, namely examining cases of object´s foundations and the possible influence of foundation pit´s symmetry on the object´s settlement. All the calculated processes in the object´s settlements are then compared to data obtained from geotechnical monitoring of the structure.
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Numerical analysis of stability of retaining structure in cohesive soils
Fejfarová, Aneta ; Račanský, Václav (referee) ; Chalmovský, Juraj (advisor)
The bachelor thesis deals with numerical modeling of excavation using finite element method in the Plaxis 2D software. Triple-anchored retaining structure is founded in a less permeable cohesive soils. There are described loss of stability, types of the calculation and material model (Hardenig soil model used in the mathematical model) in the theoretical section of this bachelor thesis. Mathematical model of the excavation was described in the practical section of this thesis, specifically first limit state. Part of the thesis is an evaluation of the degree of stability over time, pore pressures and critical shear surfaces.
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Analysis of factors influencing internal forces in primary tunnel lining and its design
Rozmánek, Filip ; Rychtecký, Josef (referee) ; Chalmovský, Juraj (advisor)
This thesis deals with the mathematical modelling of the primary lining of a tunnel which finds itself in overconsolidated neogenic clay. This type of construction is typically solved by a combination of linear-elastic beams representing sprayed concrete and a linear elastic – perfectly plastic soil material model. Both of these approaches are a simplification of the behaviour of both sprayed concrete and soil. The real behaviour of concrete is nonlinear and time-dependent when it comes to stiffness and strength. In praxis, this issue is solved by implementing phases of young and cured concrete. The real behaviour of soils is, on the other hand, influenced by hardening. The main goal of this thesis is to use an advanced time-dependent elastoplastic material model (The Concrete model) to create shotcrete lining for the Dřevnovice tunnel, built by the Kernbauweise method. A nonlinear hyperbolic soil material model (The Hardening Soil model) is applied to the neogenic clay environment. Various modelling approaches are used to obtain internal forces and deformations of tunnel lining. These approaches are then graphically compared. The last part of this thesis focuses on verifying the primary lining design of a railway tunnel in central Moravia.
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Optimization of the Material Parameters Based on Retaining Wall Monitoring
Koudela, Pavel ; Chalmovský, Juraj ; Miča, Lumír
Geotechnical monitoring is usually used for the verification of designed constructions. A result of the monitoring could be used as an alternative for the determination of material parameters involving optimization procedures. The optimization procedure will be used as a tool for determining material parameters using the inclinometer measurement of a retaining wall. The simple script involving data processing between Plaxis and optimization procedure Particle swarm optimization (PSO) was written. In this way, the input parameters of Brno Miocene clay for the Hardening Soil model were optimized. The results of the optimization procedures confirm the hypothesis, the optimization could be used as a useful tool for determining the material parameters of soils.
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Numerical analysis of stability of retaining structure in cohesive soils
Fejfarová, Aneta ; Račanský, Václav (referee) ; Chalmovský, Juraj (advisor)
The bachelor thesis deals with numerical modeling of excavation using finite element method in the Plaxis 2D software. Triple-anchored retaining structure is founded in a less permeable cohesive soils. There are described loss of stability, types of the calculation and material model (Hardenig soil model used in the mathematical model) in the theoretical section of this bachelor thesis. Mathematical model of the excavation was described in the practical section of this thesis, specifically first limit state. Part of the thesis is an evaluation of the degree of stability over time, pore pressures and critical shear surfaces.
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Prediction of foundation settlement of high-rise building using the finite element method
Červenka, Jan ; Dobrovolský, Ján (referee) ; Chalmovský, Juraj (advisor)
The focus of this thesis is to deal with reverse engineering of high-rise building settlements. This is modeled via the finite element method performed in the Plaxis 3D program. In the first part of this thesis, a calibration of input parameters of an appropriate material model – Hardening soil – is conducted. This calibration is a result of oedometric test data which were obtained within a geotechnical survey. An influence of soils over consolidation affecting calibration and the material model choice is described. Final values of reference stiffness parameters are used in a mathematical model of the focused area. This model is created for one half of the high-rise building plan, including vestibule. The high-rise building is founded in a foundation pit. The foundations of this building consist of raft foundation and piles of jet grouting. In the model, there are also changes in pore pressure during an excavation of foundation pit included. The functional model is used for parametric analyses, namely examining cases of object´s foundations and the possible influence of foundation pit´s symmetry on the object´s settlement. All the calculated processes in the object´s settlements are then compared to data obtained from geotechnical monitoring of the structure.
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