National Repository of Grey Literature 43 records found  1 - 10nextend  jump to record: Search took 0.00 seconds. 
Požáry granite and its properties influencing durability
Šťovíčková, Michaela ; Přikryl, Richard (advisor) ; Matějka, Dobroslav (referee)
Požáry Granite, cropping out on NW margin of Central Bohemian Plutonic complex, is ranked to the most valuable decorative varieties of natural stone in the Czech Republic. The stone is characterised by plausible appearance, excellent polishing ability and favourable physical properties. It has been used for numerous structures and monuments in the Czech Republic and abroad. Despite declared favourable properties, it is prone decay, specifically on the polished surface. This bachelor thesis discusses granite petrology, their weathering and usage for decorative purposes. In the second part, the thesis summarizes current knowledge on Požáry Granite. The study focuses on its position within the Central Bohemian Plutonic Complex, mineralogy, petrology, usage, and historical/current exploitation. This bachelor thesis is generally aimed as introduction to the planned master thesis which should focus on experimental study of Požáry Granite.
Jeroným Mine by Čistá (Lauterbach): current state of the knowledge and an update of geological data
Berka, Josef ; Přikryl, Richard (advisor) ; Matějka, Dobroslav (referee)
The Jeroným Mine near Čistá is a typical locality of Central European historical mining. Preserved mining areas bearing the signs of the original mining methods are the subject of the monument protection and museum exposition. The mining of tin at the Jeroným Mine, according to preserved sources, dates back to the beginning of the 16th century. The paper summarizes the geological conditions of the wider area of the Slavkov Forest and the context of the Čistá deposit. We will outline the history of mining at the Jeroným Mine and its historical significance.
Decay of granites used for ashlar masonry in arch bridges
Mach, Kryštof ; Přikryl, Richard (advisor) ; Matějka, Dobroslav (referee)
This thesis deals with the decay of the granite used for ashlar masonry in arch bridges. The aging process and the functionality decrease of the granite tend to be faster in building structures than in natural conditions. Therefore, this ongoing change need to be closely researched. At the beginning, the thesis is focused on general degradation effects on building stone, which can cause for example the reduction of material or finally its damage and destruction. Further, the character of the granite is analysed with the respect to its quality and resistance to negative influences. In this chapter, this thesis also deals with the classification of granitic rocks according to the composition and the structure, which determine the specific name of the rock. Finally, the granite stone is also used in the constructions of arched bridges as their supporting elements, namely vaults and pillars. This type of construction has been widely used in the past. One of the subchapters focuses on the case study of the Legií bridge in Prague, which is a stone arch bridge made of granite blocks. In particular, the author describes the analysis of the sample, which was processed in the petrographic laboratories at the Faculty of Science of Charles University.
Methods of study of porosity of granitic rocks in relation to rock fabric
Votavová, Klára ; Přikryl, Richard (advisor) ; Krutilová, Kateřina (referee)
This bachelor thesis focuses on granitic rocks, which are often used as a building material. Granite are generally rocks with very low porosity, which can be modified (augmented) due to e.g. weathering processes. Increase of porosity is accompanied with deterioration of other physical parameters and decrease of durability. The thesis focuses, after introducing basic petrographical and petrogenetic characteristics of granitic rocks, on the definition of porosity as a physical property, and on various methods used for its determination. Next part of the thesis discusses some case studies which underpin the significance of porosity of granitic rocks by either using combination of several methods, or by using unconventional ones. According to available data, study of porosity and its relationship to rock fabric should be performed by combining several methods of study, encompassing simple petrophysical determination of open and bulk porosities, and microscopic methods allowing for visualisation of pore space - mineral grains relationships. These can be accompanied with less common method of multidirectional ultrasonic sounding allowing for determination of spatial distribution of microcracks present in granitic rocks.
Influence of the mineralogical composition of raw material on phases formed during the burning of hydraulic lime and natural cement
Kozlovcev, Petr ; Přikryl, Richard (advisor) ; Hladil, Jindřich (referee) ; Škvára, František (referee)
Natural hydraulic lime and natural cement have been used in the building industry for centuries. These inorganic hydraulic binders are called "traditional" or "alternative" because they can, in some cases, substitute modern Portland cement. The recent increased interest in these binders is due not only to their use in restoration practices, but also because their production and use is less energetically demanding than in modern cements. Historically, many types of hydraulic binders were produced in the regions of Bohemia and Moravia. However, much information has been lost about their manufacturing process, which raw materials were used, and we are uncertain of the exact character and properties of the burned material. To date, studies have only addressed the impact of the chemical composition of raw material on the parameters of the burned material - all this is well known for Portland cement, much less for other types of hydraulic binders. The aim of this dissertation was to study the various types of raw materials (limestone containing non- carbon admixtures) and to understand the characteristics of their respective hydraulic lime and natural cement. This was done by analyzing the impact of conditions (highest achieved burning temperature and time of burning) and the mineral and chemical...
Provenance Determination of Marbles: A Methodology Based on a Complex Analytical Approach
Šťastná, Aneta ; Přikryl, Richard (advisor) ; Žák, Karel (referee) ; Török, Ákos (referee)
This PhD thesis is focused on methodology for the provenance determination of marbles from historic quarries and marble artefacts, respectively. Various petrographic, geochemical, and physical data were compiled to distinguish among different marble types, as well as to explore the suitability and limits of experimental techniques for such provenance studies. Moreover, by comparing the data obtained with the results from the artefacts the importance of the selected methodology was tested in detail. The correct determination of the source locality for marbles represents a difficult task, due mainly to both the variable characteristics of marbles coming from any one locality; and the converse, the similarity in properties between samples from different areas. Facing this complex situation, a multivariate approach proved to be necessary. Most of the previous analytical studies on marble provenance have been conducted on pure white marbles from the Mediterranean area where the methodology, based upon a combination of various mineralogical-petrographic and chemical criteria, was originally established. However, the Czech Republic is also rich in 'impure' crystalline limestones containing common noncarbonate admixtures (e.g. silicates, magnetic minerals, and carbonaceous matter) which led to the...

National Repository of Grey Literature : 43 records found   1 - 10nextend  jump to record:
See also: similar author names
1 Přikryl, R.
2 Přikryl, Radovan
1 Přikryl, Roman
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