National Repository of Grey Literature 9 records found  Search took 0.01 seconds. 
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.
100 let BOZP 1918 - 2018
Vala, Jiří
This brochure introduces the history of occupational safety and health (OSH), including OSH inspection, both in the context of the origins of Czechoslovakia and the development of legislation in which the OSH field or its aspects have been addressed. The second part is devoted to the origin, development and role of the Occupational Safety Research Institute. It presents current activities, organizational structure and challenges that are currently emerging in the OSH area and which should be solved in the framework of its research activities.
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100 let BOZP 1918 - 2018
Vala, Jiří
This brochure introduces the history of occupational safety and health (OSH), including OSH inspection, both in the context of the origins of Czechoslovakia and the development of legislation in which the OSH field or its aspects have been addressed. The second part is devoted to the origin, development and role of the Occupational Safety Research Institute. It presents current activities, organizational structure and challenges that are currently emerging in the OSH area and which should be solved in the framework of its research activities.
Fulltext: Download fulltextPDF
The exploitation of parallelization to numerical solutions regarding problems in nonlinear dynamics
Rek, Václav ; Krejsa,, Martin (referee) ; Vala, Jiří (referee) ; Němec, Ivan (advisor)
The main aim of this thesis is the exploration of the potential use of the parallelism of numerical computations in the field of nonlinear dynamics. In the last decade the dramatic onset of multicore and multi-processor systems in combination with the possibilities which now provide modern computer networks has risen. The complexity and size of the investigated models are constantly increasing due to the high computational complexity of computational tasks in dynamics and statics of structures, mainly because of the nonlinear character of the solved models. Any possibility to speed up such calculation procedures is more than desirable. This is a relatively new branch of science, therefore specific algorithms and parallel implementation are still in the stage of research and development which is attributed to the latest advances in computer hardware, which is growing rapidly. More questions are raised on how best to utilize the available computing power. The proposed parallel model is based on the explicit form of the finite element method, which naturaly provides the possibility of efficient parallelization. The possibilities of multicore processors, as well as parallel hybrid model combining both the possibilities of multicore processors, and the form of the parallelism on a computer network are investigated. The designed approaches are then examined in addressing of the numerical analysis regarding contact/impact phenomena of shell structures.
Preparation and management of the contract in the construction company
Jedlička, Jan ; Vala, Jiří (referee) ; Nový, Martin (advisor)
This diploma thesis aims to describe preparation and management of a contract in a building company using the tools of project control. The thesis contains a theoretical and a practical part, where the problem is first explained theoretically and then practically on the chosen contract. This contact is a block of flats in Stepanov, which was realized in the years 2017 and 2018 by the building company Moravostav Brno, a. s.
Material properties research for use in high-temperature solar thermal storage tank
Šot, František ; Vala, Jiří (referee) ; TROJAN,, Karel (referee) ; Steuer,, Radek (referee) ; Šťastník, Stanislav (advisor)
The use of thermal storage energy, using phase change materials appears to be an effective way to store thermal energy storage with the benefits of the high amount of energy while maintaining isothermal nature of the process. PCM methods are used in latent thermal storage systems for heat pumps, as well as in solar engineering or for temperature control in spacecraft. The past decade has extended these principles for cooling and heating in the building. There are a number of PCM systems, which operate over a wide temperature range, are used in various applications. This document includes a brief overview of the development and analysis of available thermal storage working mainly on the principle of PCM.
Construction Project Realization Planning
Jedlička, Jan ; Vala, Jiří (referee) ; Nováková, Jana (advisor)
This bachelor's thesis focuses on the basic terminology and the principles of planning the course of construction projects. The aim of this thesis is the familiarization with the methodology of planning the course of construction projects and their practical implementation on an actual project.
Wine Farmstead in Jaroslavice
Vala, Jiří ; Stříteský, Pavel (referee) ; Mléčka, Jan (advisor)
Key strategy of the project works with hidden potential of the former loess quarry and its terrain modification. Finding the closure between the winery and the landscape. To merge, to reach the symbiosis. They winemaking area is situated in the heart of the slope, to keep the wine in stable environment and creating the retaining wall at the same time. Concept is build on a traditional principles of agricultural yard and connection of partial functions through it.
Study of vacuum insulated material properties in civil engineering
Dvořák, Richard ; Vala, Jiří (referee) ; Šťastník, Stanislav (advisor)
Study of vacuum insulated material properties, their advantages and disadvantages of usage in buildings. Elaborating study of technic legislation for insulation in buildings, basic properties of heat transfer, moisture effect and other heat phenomena. Basic principles of vacuum insulated materials, their typical construction and current risks. Their next development and possible extension on market.

See also: similar author names
1 Vala, J.
2 Vala, Jan
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