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Advanced techniques in nanoindentation testing
Břečka, Jan ; Tkachenko, Serhii (referee) ; Čížek, Jan (advisor)
The aim of this thesis is to determine the suitability of using advanced indentation methods for various materials. These advanced measurement methods are described in detail and subsequently compared in terms of time complexity and accuracy of the elastic modulus and the hardness measurement. The tested materials were copper and silica. The comparison of the methods is carried out at different views and gives a general overview of advantages of these methods.
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The usage of the quarried aggregates to base layers of pavements
Borkesz, Michael ; Mondschein,, Petr (referee) ; Stehlík, Dušan (advisor)
The work deals with the possibilities of using fine crushed and quarried aggregate to base layers of roads. The introduction of the theoretical part explains the origin of this type of aggregate. There are also described the tests, which were used to verify the attributes and features of these mixtures and their use in cemented base layers of roads. In a brief way, the work also deals with foreign research and the possibilities that arise from it. In the practical part is then described the process of mixture preparing and laboratory tests carried out on them, the production of test specimens, load tests of these specimens and interpretation of the results. The conclusion summarizes the findings. Here are also discussed ways to apply them in practice.
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Diagnostics of reinforced concrete structures
Holbová, Monika ; Anton, Ondřej (referee) ; Cikrle, Petr (advisor)
This diploma thesis deals with the building survey and diagnosis of the station building of a railway station in Vítkovice. It describes process of survey and evaluation of existing reinforced concrete structures and used diagnostic methods. The survey of the object is described in the practical part of the thesis, which involves location of testing spots, taking the samples for testing from the structure, laboratory testing and evaluation of the results – determination of compressive strength of concrete with classification of concrete and elastic modulus. The last part includes static calculation of selected part of the structure.
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Performance tests of the recycled aggregates to roads
Karásková, Romana ; Valentin,, Jan (referee) ; Stehlík, Dušan (advisor)
The work is divided into two parts. The practical part deals with the testing properties of soils which are using in new road in Nové Město na Moravě and the testing of recycled materials which could replace this soils from road. The aim this part is to obtain values of elastic modulus which are then inserted into the computational model. In the second part of work the track road is modeled in the software which uses the Finite Element Method to calculate and respect physical properties of different materials and a load. The result of work will be studies with comparison of displacement and stress generated to using existing soils and recycled materials.
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Optimisation of fibre-matrix interface in ceramic matrix composite
Halasová, Martina ; Černý,, Martin (referee) ; Chlup, Zdeněk (advisor)
This thesis is concerned to the study of behaviour of fibre composites with ceramics matrix. The composite consists of pyrolysed polysiloxane matrix reinforced by ceramic fibre Nextel 720. Main aim of this work is optimisation of fibre matrix interface through the selection of suitable precursor of the matrix with respect to temperature stability, sufficient strength and reasonable fracture toughness. Samples of matrices were exposed to the long term heat treatment in the range 1100 – 1500 °C. The mechanical properties as hardness and indentation elastic modulus were determined after heat treatment. Selected precursors of matrices were used for composite fabrication. Elastic modulus and fracture toughness at room and elevated temperatures were studied. Discussion is dedicated to the description of changes in mechanical properties with respect to chemical processes taking place during high temperature exposition. Further, reasons of fracture behaviour of composite materials are discussed, and finally, gained knowledge and outlined possibilities of subsequent development are summarised.
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The influence of triaxial deformation of aggregates on properties of concrete
Fójcik, Tomáš ; Kalina, Lukáš (referee) ; Šoukal, František (advisor)
This diploma work takes focus in elastic modulus of unbound granular aggregates, which was determined by repeat load triaxial test and in deformation behaviour of unbound granular aggregates - elastic and plastic deformation. It was examine the propriety of this aggregate for its service as underlying granular material in pavement. Further, there was observed the influence of elastic modulus of unbound granular aggregates on concrete characteristics - compressive and bending strength. Finally, it was observed the influence of individual fractions of aggregates on its elastic modulus and strength of concrete.
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Comparison of selected parameters of tensile strength of concrete
Rozsypalová, Iva ; Žítt, Petr (referee) ; Daněk, Petr (advisor)
The thesis deals with a comparison of the selected strength tension properties of the hardened concrete and finding relationships between them. This is essentially a simple tensile strength, tensile flexural strength and tensile splitting strength. The text describe the testing procedures to determine the tensile strength of concrete. Furthermore, there are presented the results of testing on different types of concrete (plain concrete, lightweight concrete, steel-fiber concrete, polymer-fibre concrete and high strength concrete). The conclusion deals with the derivation of dependancy between concrete strengths and comparing the values obtained from the available relations with the results of the tests.
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Study of influence of input parameters for the numerical modeling of the compression test
Polách, Marek ; Keršner, Zbyněk (referee) ; Lehký, David (advisor)
The thesis analyses influence of input parametres of the 3D Non Linear Cementitious 2 material model for the numerical modeling of compression test performed in ATENA 2D and ATENA 3D software. The aim is to identify parametres with considerable influence and subsequently replicate the load-deflection curve obtained from laboratory compression test by numerical modeling. The effects of selected model and material model settings are studied on three kind of models in total. As tools for analyzing the effects, deterministic and statistic sensitivity analyses were chosen. Parametres with significant influence will be highlighted and added to the group of parametres obtained from numerical modeling of three-point bending test. This will create a set of parametres of considerable influence when it comes to modeling advanced structures with different types of stresses.
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