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Long Term Condition Monitoring in Order to Assessment of Existing Masonry Arch Railway Bridges
Kůrka, Jan ; Dohnálek, Jiří (referee) ; Tomek, Jan (referee) ; Hobst, Leonard (advisor)
Thesis rises from an actual needs to make standard of practice for assessment an existing arch railway masonry bridges on the basis of condition long term monitoring. Bridge assessment is a part of any inspection, especially in case of doubts arising during inspections due to heavy defects, increase of axle load or increase of train frequency, which may influence the structural safety, traffic safety or durability of a bridge. There are possibilities for utilization of monitoring results for assessment in case of investigation data absece. An important option is assessment based on satisfactory past performance by ČSN ISO 13822, chapter 8.
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Use of thermographic methods for diagnostics of concrete bridges
Janků, Michal ; Hobst, Leonard (referee) ; Matula, Radek (referee) ; Cikrle, Petr (advisor)
This dissertation is focused on the research of the applicability of the thermographic method in the diagnosis of concrete bridges in the Czech Republic. The theoretical part characterizes selected defects of concrete structures and the principle of their detection. The practical part describes the measurements made in the laboratory on the test specimen and the field on the concrete bridge. Most attention is paid to infrared thermography, ground-penetrating radar and ultrasonic pulse-echo method. Based on the results of the dissertation, recommendations for the use of the thermographic test method in practice were developed.
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Methodology of Passportization of Building Objects Damaged by Surrounding Activities
Novák, Jindřich ; Hobst, Leonard (referee) ; Anton, Ondřej (advisor)
The passportization of building structures is very important task efore the initiation of negative influences on to object. The aim is to prevent possible legal deputies in between owners of affected object. The demand of passportization of building structure is increasing with the exploding of developments projects from green fields to vacancies. The aim of this work is to determine the metodology of passportization of building structures and to apply it on existig object.
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Investigation of Ionizing Radiation Infuence to the Communication Systems of Satellites
Golubev, Martin ; Hobst, Leonard (referee) ; Katovský, Karel (advisor)
This master thesis discuss about ionizing radiation, interaction with matter and effects on her. In the work is discussed differend types of interactions of directly ionizing radiation and indirectly ionizing radiation. Below is an overview of methods of shielding from all of types of ionizing radiation. Second part of this thesis discuss about single event effects in semiconductors which are cause by ionizing radiation. At the end is described design of measuring instrument included FPGA chips. This design is discused both from point of wiew hardware and software too.
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Standardization of procedures for the brick masonry expert assessment
Kostka, Rostislav ; Myslín, Jiří (referee) ; Dohnálek, Jiří (referee) ; Hobst, Leonard (advisor)
The article is focused on the definitions of brick masonry expert assessment and brick masonry buildings assessment methodologies. The expert diagnostic procedures include building diagnostics, defects determination, static ensuring and so on. It is also necessary to choose the proper procedure of defects measurement and remediation. It is very important not to neglect the determination of costs. One of the methods that can greatly help in the process of assessing the condition of buildings is the brick masonry defects and faults monitoring with an emphasis on long-term measurements of the cracks shifts of various origin. Cracks are one of the most common disorders appearing in brick masonry buildings. In the article I compare and evaluate monitoring of the most significant cracks appearing during the excavation of Královopolský tunnel situated under Dobrovského street in Brno, where some depressions and inclinations of existing buildings had happened, as well as st. Gothard church in Brno Modřice and some masonry school building in Brno. In these selected cases the methodology of brick masonry expert assessment was verified.
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Cost Analysis of Repairs and Maintenance of an Apartment Building in Brno
Staňková, Pavla ; Hobst, Leonard (referee) ; Klika, Pavel (advisor)
The aim of this diploma thesis will be to create a plan for maintenance and repairs of the building on the street of the brothers Čapků in Brno. The first part will describe the individual concepts dealing with the life of individual structural elements, maintenance and repair and revisions of dedicated technical equipment. The second part will be focused on practice. A plan for maintenance and repairs of the building structures and a plan for revisions and inspections on the dedicated technical equipment will be prepared for the given building. The proposed plan will be designed to spread the funds over the whole period considered.
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Analysis and assessment of risks in the construction of the shielding structures of medical irradiators.
Henzelová, Iveta ; Vymazal, Tomáš (referee) ; Hobst, Leonard (advisor)
The thesis focuses on the analysis and evaluation of the potential risks in the design and implementation of shielding structures against the effects of ionizing radiation. The rocedure of calculation and design optimization, according to the current wording of the Atomic Act and related regulations, is mentioned only marginally. According to DIN EN 31010: 2011 Risk Management - Risk Assessment Technique risk assessment were made by risk analysis. risk analysis. Risk management identified these methods - Analysis of the Causes and Consequences (Ishikawa diagram), Analysis Failure Mode and Effects (FMEA) and the Pareto diagram. These methods are implemented to identify and evaluate the associated risks. Based on the identification and assessment of these risks, appropriate measures are then proposed to reduce their impact.
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Development and use of non-destructive testing methods from the point of view of forensic engineering
Bílek, Petr ; Vala, Jiří (referee) ; Vodička, Jan (referee) ; Hobst, Leonard (advisor)
Concretes reinforced by, using distributed steel reinforcements (fibres) are known as fibre-concrete. In case of disturbances or accidents of concrete structures reinforced with wires, it is necessary to carefully examine the actual implementation of dispersed reinforcement. Fibre concretes belong to modern building materials whose possible applications have not been fully utilized so far. Have been mainly used for floor structures loaded with factory halls and warehouses. Recently, thanks to well-known physical and mechanical properties of fibre-concrete, there were numerous attempts of designers, and namely investors, to utilize this kind of materials for support structures either. Favorable properties of wire-concrete can be utilized if there is a necessity to increase the resistance of concrete to stresses exceeding its strength, cyclic stress or impact stress. Daily practice shows to prove that the applications of fibre-concrete in such structures lead to the economic success. Necessary condition for successful application of steel fiber reinforced concrete in constructions however consists in its uniform dispersion, a homogeneous distribution of the wires throughout the volume of the structure. In case of inappropriate processing and deposition of the mixture during the manufacturing process fiber-concrete structures, the fibers are often unevenly distributed. Wires itself represent unfavourably shaped mixture components and they are extremely deteriorating its workability. A grouping of wires may be encountered as well, which reduces the overall homogeneity and the quality of steel fiber-concrete structures. If the homogeneity of fibre-concrete is not kept, the material possess different properties in various parts of the structure (for example, tensile strength), which can lead to defects in the structure (generation and development of cracks). The relevant lower reliability of the structure which is caused by unequal distribution of fibres (wires) in concrete volume can lead to damage of the property as well as the safety and the human lives can be jeopardized. Hence it is necessary to secure the effective control of the fibre-concrete homogeneity in ready support fibre-concrete structures. Contemporary homogeneity control is still ongoing on fresh blends, but if the fibre-concrete hardened and is a part of the construction, no known reliable methods are currently in available to test the homogeneity of the fibre-concrete on the structure without its destruction. The methods developed to control the concentration of wires in wire-concrete structures are based mostly on magnetic or electromagnetic properties of wires. The thesis deals with the development of the magnetic method in situ using permanent magnets for monitoring the distribution of fibers in hardened steel fiber-concrete structures. The test principle is based on measurements of the changes in magnetic field strength of permanent magnets which are induced by a change in wire distribution in steel fibre-concrete structure. Test is characterized as a so called local- failure- test using a small diameter core drill. In this sense it is a semi-destructive method.
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