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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Bezpečnost dopravního letounu při poškození draku teroristickým útokem / Safety of a Commercial Aircraft after Damage to Airframe due to Terrorist Attack

Lošťák, Miroslav January 2012 (has links)
Modern-day terrorist attacks present a considerable danger for commercial aircrafts. This thesis analyzes potential methods of such attacks with a critical analysis of the most dangerous type: an attack from the outside of the aircraft via a fragmentation missile warhead. Such missiles cause damage to the airframe of the aircraft through fragments created by the explosion. In this thesis, analytical geometry is used to determine the area of the aircraft affected by the fragmentation. The aircraft’s geometry and the fragments’ dispersion are calculated by analytical functions, and the effect of the damage is analyzed. A shooting experiment was also carried out, in which fragments were shot at a reinforced skin panel that was manufactured according to the real design of commercial aircraft. The results of the experiment revealed that only directly hit sections of the structure are damaged. Data obtained by the experiment was then used for the creation and improvement of the model used in the simulation by means of the finite element method. This model is used for the numerical calculation of the damage sustained. Further included in the thesis is an analysis of the change in the load-bearing capacity after such an attack. The relationship between the size of the damage and its effect on the load-bearing capacity of the component as well as the entire structure is defined. First, the effect of component damage is analyzed via the FMEA/FMECA methods. This analysis is then extended using fuzzy logic. Fuzzy logic analysis is based on the determination of the size of the damaged component area and the component’s importance on the structure’s carry loads. Application of the defined approach is described for several parts of an aircraft’s life cycle, including development, operation after the terrorist attack, and assessment of causes after a crash caused by a fragmentation missile warhead.
22

Mostový jeřáb jednonosníkový / Bridge crane one-girder

Chroust, Martin January 2018 (has links)
The focus of this thesis is the construction of a single girder overhead crane. The goal is to render a crane construction according to preset parameters. The parameters include a lifting power of 8,000 kg, a 10,000 mm reach, a 2,400 mm wheelbase and a stroke of 8,000 mm. The thesis includes brief theoretical research focused on overhead cranes, their various types and description of their main components. Brief description of chosen parameters for the construction itself follows. The description of chosen parameters includes calculations of strain acting during operation, technical and stability parameters, essential for the construction. All calculations were made with regard to valid Czech technical standards and specialized literature which focuses on the construction of cranes and their parts. Finally, the thesis is extended by the required technical drawings.
23

Zesilování ocelových nosníků výztuží na bázi FRP / Strengthening steel beams using reinforcement based on FRP

Bláha, Tomáš January 2013 (has links)
A study of an influence of strengthening steel beams using reinforcement based on FRP on a moment bearing resistance and bending stiffness. Evaluation of the theoretical calculation methods based on the performed experimental verification. Description of the production of carbon fibres and composite materials on the basis of carbon fibres.
24

Experimentální a numerická analýza zesílení ŽB prvku na ohyb / Experimental and numerical analysis of strenghtened reinforced concrete member loaded to bending

Vepřek, Karel January 2015 (has links)
Design and manufacture of test elements for experimental testing laboratory. Testing of selected mechanical characteristics of test elements. Experimental analysis of test elements in the lab, creating a mathematical model in ATENA software and static calculation. Evaluation of experimental analysis and comparison with the values of numerical analysis. Graphic comparing the results of a final overall evaluation.
25

Návrh mostu na dálnici D1 (Jánovce - Jabloňov) / Design of bridge on highway D1

Kopřiva, Jan January 2015 (has links)
The purpose of this thesis is to design bridge over the valley on D1 highway. Length of the structure is 170 meters. Main structure is four spans prestressed beam. The length of fields is 36+48+48+36 meters. The structure is examined in all phases of construction, including the operating phase according to valid standards.
26

Studie styčníků rámových ocelových konstrukcí / Study of joints of frame steel structures

Cikánek, Ondřej January 2017 (has links)
Master's thesis „Study of joints of frame steel structures“ examine certain analysis types of frame steal joints, which are analysed both by component method and by specialized software IDEA RS. Obtained results are compared by both methods, in terms of load-bearing capacity and in terms of stiffness. Theoretical joints stiffness calculation according to standard ČSN EN 1993-1-8 is included in the introductory part of the thesis. In the second part, joints are designed to bear inner forces and moments, which were created by load combination effects and then analysed.
27

Využití vnitřní kompozitní výztuže při návrhu odolných betonových konstrukcí / The use of internal composite reinforcement in the design of durable concrete structures

Koriťáková, Martina January 2022 (has links)
The diploma thesis deals with processing of determining the shear strength of concrete structures reinforced with composite reinforcement, subjected to shear force, according to five different design approaches. The theoretical part of the thesis is closely related to the project FW01010520 - "Development of bent composite reinforcement for environmentally exposed concrete constructions", which is realized at the Institut of Concrete and Masonry Structures, Faculty of Civil Engineering, Brno University of Technology. The project deals with the shear strength of concrete beams reinforced with steel and composite reinforcement in various combinations. Then the load-bearing results gained within the project are compared with the values obtained by calculations according to the solved design approaches and computer software Atena Science. The second part of the diploma thesis deals with the static design and assessment of the cell structure. The cell is designed as a room inside of the medical building, where is placed device of magnetic resonance which is the reason why the cell is reinforced with non-magnetic composite reinforcement.
28

Bezpečnost dopravního letounu při poškození draku teroristickým útokem / Safety of a Commercial Aircraft after Damage to Airframe due to Terrorist Attack

Lošťák, Miroslav January 2012 (has links)
Modern-day terrorist attacks present a considerable danger for commercial aircrafts. This thesis analyzes potential methods of such attacks with a critical analysis of the most dangerous type: an attack from the outside of the aircraft via a fragmentation missile warhead. Such missiles cause damage to the airframe of the aircraft through fragments created by the explosion. In this thesis, analytical geometry is used to determine the area of the aircraft affected by the fragmentation. The aircraft’s geometry and the fragments’ dispersion are calculated by analytical functions, and the effect of the damage is analyzed. A shooting experiment was also carried out, in which fragments were shot at a reinforced skin panel that was manufactured according to the real design of commercial aircraft. The results of the experiment revealed that only directly hit sections of the structure are damaged. Data obtained by the experiment was then used for the creation and improvement of the model used in the simulation by means of the finite element method. This model is used for the numerical calculation of the damage sustained. Further included in the thesis is an analysis of the change in the load-bearing capacity after such an attack. The relationship between the size of the damage and its effect on the load-bearing capacity of the component as well as the entire structure is defined. First, the effect of component damage is analyzed via the FMEA/FMECA methods. This analysis is then extended using fuzzy logic. Fuzzy logic analysis is based on the determination of the size of the damaged component area and the component’s importance on the structure’s carry loads. Application of the defined approach is described for several parts of an aircraft’s life cycle, including development, operation after the terrorist attack, and assessment of causes after a crash caused by a fragmentation missile warhead.
29

Ověření spolupůsobení základové desky a piloty / Verification of interaction between the foundation plate and the pile

Kozáková, Marcela Unknown Date (has links)
The doctoral thesis deal with the interaction between the foundation plate and deep foundation in the form of bored piles in the case of skeleton construction. The issue of tension redistribution from the column between the plate and the pile is investigated on specific object – „Shopping and entertainment center Fórum Nová Karolina”. On this object were selected columns monitored and load tests of the piles was executed. Values of the axial loading of the piles and the actual deformation of the construction have been derived from measurements and tests. They were compared with the results of structural behavior by numerical modeling.
30

Vyhodnocení zatěžovacích zkoušek pilot z tryskové injektáže / Evaluation of loading test of jet-grouted piles

Čechová, Simona January 2021 (has links)
The master thesis consists of a theoretical part and a practical part. In the theoretical part jet-grouting technology is described briefly. Mechanical properties of jet-grouted piles were characterized. Various estimation methods of ultimate pile bearing capacity are described in this thesis – analytical calculation of ultimate bearing capacity for bored piles and estimation of ultimate pile bearing capacity by analysis of load-displacement curve defined by CHIN (1970; 1972). Load transfer method for piles and hyperbolic load-transfer curve are introduced. As a part of the load-trasfer method analysis, a method of estimating ultimate pile shaft friction called beta method is defined. In the practical part were evaluated several static load tests of jet-grouted piles and were constructed their load-displacemnt curves. Then reverse analysis of the results from static load tests was performed using load-transfer method. Then ultimate pile bearing capacity was estimated using analytical calculation of pile bearing capacity for bored piles and using analysis of load-displacement curve with method by CHIN (1970; 1972). By evaluation of load transfer method and beta method ultimate shaft resistence for each pile was estimated. Results and load-displacement curves were compared.

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