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Structure-Space-City "Urban block completion"
Czapek, Jakub ; Hybská, Bohumila (referee) ; Nový, Vítězslav (advisor)
The diploma thesis deals with the creation of a design of a new apartmen building in the city of Brno on the plot expected to be completed by the city block. Typologically it deals with the current design possibilities of gallery apartment buildings / porch houses, implementation of space-demanding grocery stores and commercial areas into urban structures. Architecturally explores the possibilities of designing new constructions with citation of architectural language a tectonics of past styles.
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Nonlinear analysis of reinforced concrete structures
Král, Petr ; Salajka, Vlastislav (referee) ; Hradil, Petr (advisor)
The aim is to design and evaluate nonlinear beams analysis, which will be subjected by four – point bending. Nonlinear analysis will be performed and evaluated on three beam models, the first of which will be made from plain concrete, the second of which will be made from reinforced concrete with reinforcement bars in the domain of tensile stress and the third of which will be made from reinforced concrete with reinforcement bars in domains of tensile and compressive stress. The thesis will be included formation of appropriate FE models, performance of nonlinear calculations with using nonlinear material model from a library of nonlinear material models multiPlas in the programming environment of software ANSYS and subsequent evaluation of results. Evaluation of results will consist from evaluation of nonlinear beams analysis and from evaluation of beams analysis according to ČSN EN 1992 – 1 – 1 without reinforcement bars and with reinforcement bars in these variants, next from comparison of nonlinear beams analysis with a beams analysis according to ČSN EN 1992 – 1 – 1 and finally from evaluation of the yield condition, which will be applied to the beams.
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Optimization of parameters of dynamic relaxation in solving plastic limit states of structures
Poláček, Milan ; Nevařil, Aleš (referee) ; Vlk, Zbyněk (advisor)
The aim of the thesis is to create an analytical model of frame construction. Determining load at which individual plastic hinges are formed until the collapse of the structure. The analysis is going to be performed by RFEM with an additional module RFDYNAM. Subsequently, the parameters of dynamic relaxation is going to be optimized to specify and speed up the calculations. Finally, the optimized parameters is going to be used to analyze the storeyed frame construction formed Ing. Jan Vales including a comparison of findings.
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Computational analysis of cross roll straightening of rods
Štourač, Vít ; Šebek, František (referee) ; Petruška, Jindřich (advisor)
Today is on products from the perspective of quality placed an increasing emphasis. This work is focused to the analyze of cross roll straghtening of long semifinished products with a circular cross-section. This process increased quality of semifinished products from the perspective of their curvature, because they do not reach the required limit values. Curvature of the semifinished product is due to residual stress, which is during straghtening using plastic deformation of the material redistributed and the semifinished product is leveled. This work analyzes the effect of rotation of straightening rolls on the distributiom of contact pressure between the straightening semifinished product and the roll of straightener. Author then analyzes effect of input parameters of program to straightening at the final curvature of the semifinished product. With the experience gained, then try to adjust some input parameters.
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Parameter Identification for Elastic-plastic Material Models from Experimental Data
Jeník, Ivan ; Šebek, František (referee) ; Kubík, Petr (advisor)
This master's thesis deals with the identification of the material flow curve from record of tensile test of smooth cylindrical specimen. First, necessary theory background is presented. Basic terms of incremental theory of plasticity, tensile test procedure and processing its outputs are described. Furthermore, possibilities of mathematical expression of the elastic-plastic material constitutive law, thus mathematical expression of the material flow curve itself. Mechanism of ductile damage of material is explained briefly as well. Overview of recent methods of the flow curve identification is given, focused on cases, when the stress distribution in a specimen is not uniaxial. That is either kind of analytic correction of basic formulas derived for uniaxial stress state, or application of mathematical optimization techniques combined with numerical simulation of the tensile test. Also unusual method of neural network is mentioned. For 8 given materials, the flow curve identification was performed using different methods. Namely by analytic correction, optimization, sequential identification and neural network. Algorithms of the last two methods were modified. Based on assessment of obtained results, application field and adjusting the parameters of single algorithms was recommended. It showed up, that an effective way to the accurate and credible results is the combination of different methods during flow curve identification procedure.
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Methylene Blue Test for Plasticity Determination of Brick Clays
Jiroušek, Štěpán ; Stančík,, Hynek (referee) ; Sokolář, Radomír (advisor)
The Bachelor thesis is focused on methods for assesing the plasticity of ceramic raw materials (clays). The theoretical part describes the origin, species, chemical and mineralogical composition of these raw materials. Then we describe the preparations and standardized and nonstandardized methods of assesing the plasticity of clay used in the Czech Republic and abroad. The practical part describes executed tests of brick soils specimen used in the Czech Republic. The outcome of this work is to find correlations between these tests and the determined value of sorption of methylen blue.
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Computational analysis of residual stresses in autofrettaged high pressure rails
Blaha, Jakub ; Petruška, Jindřich (referee) ; Vrbka, Jan (advisor)
The master‘s thesis is aimed on numerical simulation of autofrettage of high pressure fuel vessel – rail in Common Rail system. First there is described Chaboche model, which is later used for simulation of autofrettage. There are described different approaches which can be used to obtain sufficient material model. Then there is observed influence of these different approaches on stress state of rail within the process of autofrettage. Suitability of Chaboche model for autofrettage and re-autofrettage simulations is assessed by comparing with more complex Jiang model. In the end there is a study of influence of autofrettage pressure on different properties, especially on residual stresses.
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Possibilities of the description of stress-strain curves for computational simulations
Košťál, Josef ; Halabuk, Dávid (referee) ; Šebek, František (advisor)
Tato bakalářská práce se zabývala problematikou určování křivky zpevnění (taktéž „flow curve“) z experimentálně změřených výstupů tahové zkoušky a regresí této zjištěné křivky nelineárními vztahy. Byl prezentován teoretický základ zkoušky tahem a jejího výstupu a také byly popsány rozdíly mezi smluvním a skutečným napětím a přetvořením. Dále byla zmíněna analytická korekční metoda (Mirone-La Rosa) pro odhadnutí trendu křivky zpevnění. Tato metoda využívá standardních výstupů tahové zkoušky. Dále byly vypsány elasto-plastické po částech spojité materiálové modely, a navíc byly vybrány a detailněji rozebrány 4 nelineární vztahy pro popis křivky – Hollomon, Ludwik, Swift a Voce. Následně byla použita metoda konečných prvků pro určení a zkalibrování křivky zpevnění oceli 18CrNiMo7-6, změřené tahovou zkouškou. Pouze standardní výstup tahové zkoušky byl potřeba pro kalibraci. Křivka zpevnění byla zkalibrována iterační výpočtovou metodou na základě srovnání reakční síly ze simulace se silou z experimentu. Nakonec bylo vytvořeno uživatelské prostředí pro nalezení nejlepší regrese ze čtyř vybraných nelineárních vztahů.
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Study of impact of a transport vehicle into a structure.
Sychrová, Šárka ; Salajka, Vlastislav (referee) ; Němec, Ivan (advisor)
Master's thesis deals with the analysis of the impact of transport vehicle on a building structure. Transport vehicle is represented by an airliner and building structure is represented by a containment of a nuclear power plant. The aim of thesis was to explore the possibility of numerical simulation of an impact of transport vehicle on a building structure utilizing the RFEM program and evaluation of the damage extent.
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