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Geotechnické řešení protipovodňových opatření
Krajčovič, Ján ; Chalmovský, Juraj (referee) ; Račanský, Václav (advisor)
Main target of work is problematic of flood protection systems and possibilities of improvement of them by methods of geotechnical solutions. Parts of work are overview of basic flood protection systems and resume of normative requirements for design of levee against flood. Practical part of work is composed from complex overview of geotechnics methods used for levee improvement. Work is ended by examples from practice.
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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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Sheeting of Foundation Pit
Vodáček, Ondřej ; Chalmovský, Juraj (referee) ; Glisníková, Věra (advisor)
First part of the thesis talks about pit sheeting in general, including shafts and trenches as well as pits, however pits are the very main topic and therefore described in details. This part also discusses earth pressure and groundwater issues as applied loads, yet only marginally. Second part demonstrates a particular sheeting structure and its calculation. All presumptions are established here, including double-anchored sheet pile wall geometry, spoken earth pressure loads and groundwater loads plus heavy equipment load during a construction. The calculating process is shown using computer softwares (Plaxis 2D, GEO5) and also in a non-software way using just pen and paper. At the very end of thesis an ultimate limit state (ULS) of sheet piles is assessed, software and non-software results are compared to each other and discussed.
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Load-displacement behavior of ductile micropiles in cohesive soils
Stoklasová, Andrea ; Račanský, Václav (referee) ; Chalmovský, Juraj (advisor)
This thesis is focused on creation of mobilization curves, based on data, obtained from standard and detailed monitoring of the load test. The load test was performed on the 9 meters long ductile micropile. The first part of the thesis explains the methods and principles, which was used to construct the mobilization curves. Next there is description of the technologies of ductile micropiles and the load test. In the next part of the thesis is generally explained process, which was applied to the evaluated data. For evaluation was used spreadsheet Microsoft Excel and programming language Matlab, with Kernel Smoothing extension. In the last chapter of the thesis there are interpreted the load transfer function together with skin friction and micropile displacement.
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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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Laboratory tests of geomechanical properties of Brno clay on reconstituted samples
Rozmánek, Filip ; Koudela, Pavel (referee) ; Chalmovský, Juraj (advisor)
This theses is focused on geomechanical properties of reconstituted Brno clay. The properties of reconstituted soils are different from properties of natural soils because of the ifluence of structure. The properties of reconstituted soils are termed „intrinsic properties“. Object of this theses is to describe these properties and to determine compressibility and strenght charakteristics of Brno clay using reconstituted samples. These charakteristics are obtained using the edometer machine, the triaxial machine and the ring shear apparatus. Calculated data are then compared with known data from literature.
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Design of excavation in the Brno city centre
Kováč, Vladimír ; Miča, Lumír (referee) ; Chalmovský, Juraj (advisor)
The work deals with the problem of the ultimate and serviceability limit state of a once-anchored retaining structure of an excavation on Krenova street in Brno. The calculation of the ultimate limit state is solved manually and provides an input into the serviceability limit state, which is solved by means of a numerical analysis using a finite element method. To calculate the serviceability limit state, these constitutive models: Mohr-Columb, Hardening soil and Hardening soil small strain model are used.
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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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Determination of input parameters of advanced soil constitutive models using optimization methods
Koudela, Pavel ; Miča, Lumír (referee) ; Chalmovský, Juraj (advisor)
Choice of the constitutive model and determination of input parameters are necessary for a successful application of numerical methods in geotechnical engineering. Higher complexity of modern constitutive models results in an increase of the number of input parameters and time requirements for their calibration. Optimization methods are a possible solution for this problem. An application in which metaheuristic optimization method Particle swarm optimization (PSO) is involved is presented in this thesis. Critical review and testing of various PSO alternatives was performed in the first part of this thesis. The most efective PSO alternatives were chosen. In the second part connection between PSO algorithm and finite element solver was prepared. Automatization of determination of constitutive models input parameters was performed on three boundary value problems: laboratory test (oedometer), in-situ test (pressuremeter) and geotechical construction (retaining wall). Three types of constitutive models are used. Linear elastic-perfectly plastic Mohr-Coulomb model, elastoplastic non-linear Hardening soil model and Hardening soil - small strain model.
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Dilatancy of soils as a factor influencing the bearing capacity and load - displacement response of deep foundations
Dvořák, Tomáš ; Koudela, Pavel (referee) ; Chalmovský, Juraj (advisor)
In theory of soil mechanic the dilatancy has a significant influence, which may fundamentally affect bearing capacity and behavior of geotechnical constructions. In the past it was difficult to include influence of dilatancy directly in to calculation, but now with development of numerical analysis and growth of computer performance it is much easier. In this work there are introduced fundamental dilatancy models and phenomen called constraint dilatancy, which causes stress changes in soil or at soil – construction interface. This stress changes may lead to higher bearing capacity. In this work, the effect of constraint dilatancy is focused on bored pile’s shaft. Next target of this work is including dilatancy to calculation. By empirical methods, by direct application with theory of cylindrical cavity expansion and last by numerical calculation with finite element method in software Plaxis with using the Hardening Soil model.
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