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Granites of Prague stone arch bridges in 19th c.: sources, properties, and weathering
Rauvolfová, Hana ; Přikryl, Richard (advisor) ; Krutilová, Kateřina (referee)
This thesis deals with the topic of the degradation of granite masonry, which was used for the construction of two stone arch bridges in Prague. Granite is used as a popular building material for its high durability however it is still necessary to check the condition of the masonry, especially in cities where stone is subject to different degradation process than stone in nature is exposed to. The first chapter is devoted to description of granite from a petrographic point of view, its physical and chemical properties and the important properties that makes it a popular building stone. Furthermore, the classification of granitic rocks and important quarries in Czech Republic is described here. The next chapter is dedicated to the description of the degradation process that negatively affect the rock. Degradation processes are divided into three categories: physical, chemical and biodegradation. Degradation processes are described here in general, but the results of tests performed when measuring degradation on granite historical buildings from abroad are also presented here. The last part of this thesis is dedicated to stone arch bridges, their most common faults and repair methods. They focus more on the two Prague bridges from the 19th century, the Legií bridge and the Palacký bridge, for the...
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Influence of composition and fabric of volcanic rocks on their technological properties
Krutilová, Kateřina
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)...
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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.
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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 the problem of porosity of granites. The introductory part of the thesis describes granites, their origin, and classification. Specific concern is given to granites as building materials; therefore factors influencing the quality and durability of building stone are mentioned. Porosity of granites can be observed by several different methods. However, none of the methods provides accurate information on present pores from all points of view. From the methods used, mercury porosimentry performed under laboratory conditions seems to be one of the most effective methods. Other effective approaches are microscopic techniques, such as a scanning electron microscopy with energy dispersive spectrometry and/or optical microscopy. Generally, it is suggested to combine several methods to combine information on the volume and distribution of pores with their shape and size.
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Influence of composition and fabric of volcanic rocks on their technological properties
Krutilová, Kateřina
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)...
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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)...
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Mineralogical and petrographic study of opuka stone from various constructional phases of the Church of the Beheading of St. John the Baptist in Dolní Chabry
Šídová, Kateřina ; Přikryl, Richard (advisor) ; Krutilová, Kateřina (referee)
The objective of this thesis is to determine the mineralogy and petrography of 13 'opuka' stone samples taken out from different construction phases of the Church of the Beheading of St. John the Baptist in Dolní Chabry. The analysis of a mineralogical composition and structural properties of the extracted samples alongside with a comparison of their physical characteristics provided a basis for estimation of the samples' origin within the construction phase. Methodology used for the samples analysis has been inspired by the methods described in project NAKI (no. DF13P01OVV008 ) also known as "Materiálový rozbor přírodního kamene - opuky - exaktními laboratorními metodami jako nástroj ke stanovení zdrojové oblasti". These methods includes besides macro and microscopic analysis also X-ray powder diffraction and high pressure mercury porosimetry which together provided a complete set of data about the samples. For the purpose of obtaining the general characteristic of the rock and the initial estimate of the content of mineral phases within it the optical microscopy was used. The results made it possible to classify the samples into four groups depending on content of a silica matrix. This in turn allowed to link some of the samples conclusively with some of the older construction phases of the site....
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Physical and mechanical properties of Carboniferous arkoses from Březín natural stone deposit
Čada, Martin ; Přikryl, Richard (advisor) ; Krutilová, Kateřina (referee)
The aim of the thesis is to determine the levels of the physical and mechanical properties of chosen sedimentary (siliciclastic) rocks and also to describe their microstructural nature. With respect to the intended use of the studied material (building stone raw material) the laboratory testing methods are presented. The samples were taken from the drill cores and also from the surface blocks in locality "Zlatý lom" Březín situated in western Bohemia. The microstructural phenomena in the samples were studied using optical microscopy and digital image analyses. According to Folk's classification (1980) the name of the rock was lithic arkose. The strength testing methods were represented by unconfined compressive strength and the Brazilian test. The rest of the mechanical parameters were determined in form of Young's modulus, shear modulus and Poisson's ratio. Special emphasis was given to the hydric expansion (after full immersion) test. The other physical methods were used in order to describe the pore space and real density of samples. For this purposes the absorption test, mercury intrusion porosimetry and helium pycnometry were performed. Besides the porosity value, the pore-size distribution histograms were obtained. In order to calculate the theoretical density of the rock MINLITH and MODES...
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Weathering forms of brick-wall surrounding Regional Maternity Hospital in Prague and their interpretation
Jablonský, Jakub ; Přikryl, Richard (advisor) ; Krutilová, Kateřina (referee)
This diploma thesis focuses on the weathering of firing bricks used for construction of the walls at the Regional Maternity Hospital U Apolináře in Prague. This wall shows significant marks of weathering, such as black crusts of gypsum on the original bricks surface, blistering, spalling and powdering in the worst cases. The poor quality of the bricks is caused by a low firing temperature (aprox. 800 - 900řC). This leads to a lack of pores bigger than 3 μm, which have positive influence on high performance of bricks against freeze-thaw cycles and effect of water soluble salts. This thesis aims to find the source of raw material for production of bricks, determination of their mineralogical composition and their basic geotechnical survey, as well as determination of weathering forms and their intensity by detailed field study of the wall. The relationship between properties of bricks and weathering forms will be studied by optical microscopy, XR diffraction, which allows to estimate mineralogal composition of bricks and their firing temperature. Ion changing chromatography identifies concentration of water soluble salts in the wall and their relationship to porosity of surface area and cores of bricks which will be detected by mercury intrusion porosimetry. Results will be useful for restoration...
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