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Final research report to the project PB-2014-ZL-U2301-004-BUKOV
Souček, Kamil ; Vavro, Martin ; Staš, Lubomír ; Kaláb, Zdeněk ; Koníček, Petr ; Georgiovská, Lucie ; Kaláb, Tomáš ; Konečný, Pavel ; Kolcun, Alexej ; Králová, Lucie ; Kubina, Lukáš ; Lednická, Markéta ; Malík, Josef ; Martinec, Petr ; Ptáček, Jiří ; Vavro, Leona ; Waclawik, Petr ; Zajícová, Vendula
Bukov Underground Research Facility (Bukov URF) has been built as a test site to assess the properties and behaviour of the rock mass analogous to selected candidate sites. It is situated at a depth corresponding to the proposed storage depth of the final locality for the Czech Republic´s deep repository of high-level radioactive waste. Bukov URF is located in the Vysočina Region, the cadastral district of Bukov, approx. 3 km south-eastwards from the municipality of Dolní Rožínka. The underground research facility is placed approx. 300 m from the Bukov-1 shaft, namely on the level 12 of the shaft, at the depth of about 550 – 600 meters below the Earth’s surface. As for the regional geology, Bukov URF is found at the southern part of the Rožná uranium deposit, at the north-eastern edge of the Strážek Moldanubicum close to its contact with the Svratka Unit. The rock mass is composed of a relatively monotonous sequence of differently migmatized biotite gneisses to stromatic migmatites, continuing with amphibole-biotite to biotite-amphibole gneisses and amphiboles, with occasional fine intercalations of aplites, pegmatites or calc-silicate rocks (erlanes). Between 2013 and 2017 and within the complex geotechnical characterization of the Bukov URF, the Institute of Geonics of the Czech Academy of Sciences (Ústav geoniky AV ČR, v.v.i.) in Ostrava carried out a series of laboratory and field works in order to provide a detailed description of the geotechnical and geomechanical properties and quality of the rock mass. The works included the determination and assessment of the physical-mechanical properties of the rocks sampled from the walls, boreholes and ground surface in the locality, the determination of stress state and deformation properties of the rock mass using the methods of hydrofracturing of borehole walls, Goodman Jack and CCBO, or CCBM, determination of the rock mass quality based on selected index geomechanical properties, periodic, long-term strain-gauge measurements and convergence measurements, and the assessment of the effect of technical and mine-induced seismicity on the rock mass of interest. The implemented set of research works was supposed to render a sufficient and integral whole of geotechnical and geomechanical knowledge vital for the subsequent implementation of extensive research experiments focused on long-term safety and technical feasibility of the future national deep repository of radioactive waste.
Influence of composition and fabric of volcanic rocks on their technological properties
Krutilová, Kateřina ; Přikryl, Richard (advisor) ; Vavro, Martin (referee) ; Holzer, Rudolf (referee)
Because of a very variable geological composition of the Czech Republic, there is a various scale of all genetic types of rocks that are used for the production of crushed stone. The most often used group of rocks are effusive magmatic rocks, which represent about 34 % of crushed stone marketed (Starý et al. 2010). These rocks are used for all kinds of construction purposes including roads. The experimental material of crushed stone used in this thesis was sampled from 40 active quarries in the Czech Republic. The studied volcanic rocks originated from Neoproterozoic and Paleozoic complexes of Barrandien, Carboniferous and Permian of Krkonose Piedmont Basin, Carboniferous and Permian of Intrasudetic basin, area of ordovician Železné Hory, from the main volcanic center of Bohemian Massif in the north-west Bohemia (České středohoří Mts. and Doupov Mts.), Neovolcanic area of Czech Cretaceous basin and area of Neovolcanic East and West Sudeten. Petrographic study was carried out in a form of standard petrographic analysis of thin sections and chemical analysis, which helped inclusion of rocks to a classified systems. The whole suite of volcanic rocks was separated to five petrographic-technologic subgroups defined as: (1) rhyolites / porphyres, (2) phonolites, (3) basalts s.l., (4) spilites and (5)...
ASR potential of quartz in experimental mortar bar specimens
Kuchyňová, Markéta ; Kuchařová, Aneta (advisor) ; Vavro, Martin (referee)
The alkali-silica reaction is one of the most damaging chemical reactions taking place in concrete, which can cause fatal damage. ASR originates under following conditions: high moisture (> 80 %), sufficient amount of alkaline ions (Ca2+ , Na+ , K+ ) and use of reactive aggregates (low crystaline or deformed quartz, amorphous SiO2). Reactive aggretates react with high alkaline pore solution and produce hydrofile gels. These gels absorb water and swell. Dilatometric test methods are commonly used to evaluate the reactivity of aggregates. The principle of dilatometric test methods is simple. Mortar or concrete prisms are created in a laboratory, then they are stored in the special environment, which accelerates the inception of ASR. The creation and expansion of alkali-silica gels cause prism's length changes. The major goal of this diploma thesis was to evaluate the alkali-silica reactivity potential of quartz-rich rocks using microscopic (polarizing microscopy, scanning electron microscopy combined with SEM/BSE image analysis) and dilatometric (ASTM C1260, RILEM AAR-4.1) methods. Rocks were assessed as reactive, potentially reactive and non-reactive by the ASTM C1260 method. The reactivity of aggregates was connected with the amount of cryptocrystaline matrix, grain size, shape of grain boundaries,...
Modification of rock fabric of clastic sedimentary rocks due to the Schmidt hammer test
Snížek, Petr ; Přikryl, Richard (advisor) ; Vavro, Martin (referee)
iv Summary Schmidt hammer is the instrument which is used for the assessment of rock mechanical properties and this instrument is classified as the indirect method. This method is based on the assessment of rebound value (R) of the Schmidt hammer, which is measurred by the amount of rebound of the impact plunger from the surface of tested rock. Schmidt hammer is called as the non-destructive method of rock assessment and it is called as in situ testing method as well. The main objective of this work is provement, that Schmidt hammer testing is destructive method and define degree of damage which is caused in the rock mass. Sedimentary rocks were used for the testing, mostly sandstones and arkose sandstones with different types of cement. This made it possible to test the fraction of the rock mass and the relation between fraction and type of cement. The clasts of the rocks had different properties than it was possible to find the relation between grain size and fraction of the rock. Already in procedure of the testing by Schmidt hammer it was obvious, that this metod is definitely destructive. Rock surface after hitting by plunger of Schmidt hammer gains macroscopically observeable destruction. On the surface is the circular track of the plunger and the surface is grinded. It is possible to wipe the small...
Experimental study of Palaeozoic limestones of the Barrandian and their possible use for burning of hydraulic limes and natural cement
Kozlovcev, Petr ; Přikryl, Richard (advisor) ; Vavro, Martin (referee)
54 Summary In this experimental study, selected Devonian limestones of the Prague Basin (i.e. samples from the historic quarry of Branické skály) were examined to find their suitability for production of hydraulic limes or for natural cement. Four representative samples of the dvorecko-prokopské limestone were sampled in the form of blocks weighing approximately 10 kg each, from the layer of the quarry wall that had been chosen based on literature research. A detailed mineralogical-petrographic examination of samples was the first step, in an attempt to obtain their mineralogical composition, microstructure and texture. Samples were analysed by polarizing microscopy and cathodoluminescence of thin sections, and X-ray diffraction of insoluble residues determined by treatment with both the hydrochloric acid and the acetic acid solution. Mineralogical composition of the insoluble residuals was illite, kaolinite, quartz and Na-plagioclase (albite). Two samples contained among above mentioned mineral phases also chlorite. The utility of studied limestones for the production of hydraulic binders (hydraulic limes and natural cement) was derived from both the calculations based on obtained chemical analyses (included standard cement and lime indexes and modules) and the firing experiments. The firing experiments...
Utilization of waste material from the glass-sand production
Zach, Jaroslav ; Přikryl, Richard (advisor) ; Vavro, Martin (referee)
The presented diploma thesis is focused on possible use of waste from glass and foundry sands deposits of Provodín. The mineralogical and chemical composition, mechanical and physical properties, the specific surface area and parameters of pore area were studied. X-ray analysis proved the presence of kaolinite, illite, quartz and accessory microclin. Silicate analysis shows dominant presence of SiO2 80.52%, then Al2O3 11.36% and K2O 2.14%. This diploma thesis is focused on a possible use of studied material at three main areas: the potential use as a clay component in a raw material mixture for making of hydraulic lime, the use as a kaolinite absorbent and the potential use as a geotechnical material. The studied material was experimentally mixed with limestone in a ratio of 10; 15; 20 a 25 wt %. This mixture was subsequently burnt in the temperature range from 850 to 1,200řC. New phases were identified by an X-ray diffraction analysis. The results prove the presence of characteristic phases for hydraulic limes (C2S, C3A, C4AF). The formation of new phases depend on the temperature. The most of them are formed at a temperature of 1050řC and higher. For the characterization of a specific surface area and parameters of pore areas there were used simple studied material and thermally modified samples...
Experimental study of alkali-silica reactivity of volcanic rocks
Seidlová, Zuzana ; Přikryl, Richard (advisor) ; Vavro, Martin (referee)
(AJ) Even today, alkali-silica reaction is a significant problem in concrete-making industry. It was first described in 1940 by Stanton and since then the study of alkali-silica reaction of aggregates has proceeded notably. Despite these findings, not everything has been resolved and not all the causes and consequences of this reaction are known. To detect the alkali-silica reaction in the aggregates many methods are used, such as petrographic methods, chemical methods, and expansion tests, which examine the expansion of concrete due to the reactivity of aggregates. Petrographic methods evaluate qualitative and quantitative characteristics of aggregates but can not guarantee whether they still do not cause the reaction. Chemical tests and expansion tests provide so- called potential response (non-reactive, reactive and potentially reactive aggregates), but even they have their errors and can not be taken as a 100% indicator of the presence of alkali-silica reaction of aggregates. The thesis describes the general characteristics of alkali-silica reaction of aggregates, the mechanisms and the factors influencing its formation. It describes the fraction of the concrete in which some volcanic rocks have been used, and which are in some works identified as potentially reactive by the alkali-silica...
Preliminary evaluation of sites for long-term safety - a detailed factual and timetable of work
Havlová, V. ; Pertoldová, J. ; Mixa, P. ; Uhlík, J. ; Vavro, Martin ; Maryška, J. ; Černík, M. ; Vašíček, R.
Tato zpráva obsahuje Podrobný věcný a časový harmonogram prací ZL Předběžné hodnocení lokalit z hlediska dlouhodobé bezpečnosti, zaměřeného na hodnocení vhodnosti lokalit pro umístění hlubinného úložiště VJP a RAO na základě archivních informací, , také na základě průběžných výsledků ze probíhajících projektů a geologického průzkumu prováděného pomocí metod prováděných z povrchu. \nLokality budou hodnoceny podle následujících charakteristik, důležitých pro dlouhodobou bezpečnost:\n1) Popsatelnost a predikovatelnost lokality\n2) Hydrogeologické vlastnosti horninového prostředí\n3) Stabilita lokality (seismické, klimatické, vertikální pohyby, postvulkanické jevy)\n4) Pravděpodobnost intruze/invaze člověka do úložiště\n5) Transportní vlastnosti horninového prostředí\n6) Slučitelnost horninového prostředí s navrženým systémem inženýrských bariér\nŘešení bude probíhat v 5 etapách\n1) Podrobný věcný a časový plán řešení projektu \n2) Hodnocení lokality Čihadlo (první fáze)\n3) Hodnocení ostatních lokalit (první fáze)\n4) Hierarchie kritérií či indikátorů vhodnosti lokalit a způsob hodnocení lokalit \n5) Hodnocení lokalit (druhá fáze)\nŘešení projektu je zajištěno účastí širokého týmu řešitelů, kteří buď participují na řešení probíhajícího projektu Výzkumná podpora hodnocení lokality, nebo splňují vysokou kvalitu odborné erudice.\n

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