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This thesis deals with the influence of cyclic temperature changes on the surface of a rock mass on temperature and stress fields inside the rock slope and their influence on local and overall slope stability. The review part deals with the evolution and stability of rock slopes with a focus on temperature oscillations. Furthermore, thermal parameters of rock masses, rocks and minerals are discussed. In the practical part a 2D numerical linear-elastic model of the response of the rock slope Pastýřská stěna in Děčín to cyclic temperature changes during different periods was developed. It was used to determine the depth of penetration of temperature cycles and the associated changes and redistribution of stresses within the mass and the zones susceptible to mechanical failure of the rock. iii

The submitted work is focused on selected rock-climbing areas in the Czech Republic, characterizes those areas by terms of their location and the predominant type of rock, shows and describes the characteristics of the individual rocks, including their propensity to destruction by natural as well as anthropogenic factors. Included in this work is also a brief introduction to the history of rock climbing in our country and describing the differences in the rock-climbing techniques and the usage of different rock-climbing equipment on each type of rock. The last part focuses on the possibilities of protection of often inadvertently damaged rocky areas, including photo documentation of the various types of damage with added commentary.

The diploma thesis deals with the study of stable isotopes of oxygen and carbon of Cretaceous rocks from the Jičín volcanic field. The aim of the thesis is to identify isotope alterations in Cretaceous sediments transported by basic magmas in the form of xenoliths and to determine the origin of oxygen and carbon of hydrothermal vein carbonates that penetrate the bodies of neovolcanites. The study is divided into two parts. The theoretical part summarizes in general the stratigraphy of the Czech Cretaceous Basin and Cenozoic volcanism of the Bohemian Massif, geochemistry of stable isotopes of oxygen and carbon and geology of studied localities in the Jičín volcanic field. The practical part presents a detailed isotope study of Hřídelec, Kulatý vrch, Zebín, Veliš and Kunětická hora localities. Cretaceous rocks from xenoliths in these neovolcanites show extreme variability in the isotopic composition of both carbon (from 0,15 to -11,1 ‰ V-PDB) and oxygen (from -5,4 to -22,9 ‰ V-PDB). They significantly exceed the variability of the isotopic composition of diagenetically altered Cretaceous rocks from the same area. The wide range of oxygen isotope composition is the result mainly of fluid temperature variability (approx. 300 - 20 řC), which isotopically altered Cretaceous sediments. Carbon isotope...

Water in porous rocks (e.g. sandstone) plays a fundamental role in their disintegration. However, the places where water enters the sandstone rocks are somewhat overlooked. At two sites in the Český ráj region, I use Karsten tube to measure capillary water absorption (CWA) of natural sandstone exposures and, using TDR (Time Domain Reflectometry) method, I study movement of water in a shallow zone of ruiniform sandstone landscape. The CWA differed up to four orders of magnitude at a distance of tens of meters, mostly depending on the type of the surface. The highest CWA was measured at highly weathered surfaces, the second most absorbent were less weathered surfaces covered with a biologically-initiated rock crust. The horizontal surfaces on the tops of the rock formations were even less absorbent, probably due to clogging by fine particles from soil. Surfaces covered with iron crust were the least absorbent. The differences between those surfaces are significant. After simulated infiltration, the maximum rate of the propagation of the wet front in the sandstone was from 5,5.10-6 do 1,9.10-4 m.s-1 measured by TDR. The water propagated at this rate only to a certain depth (the first tens of cm), but then the propagation stopped or slowed down rapidly. From a long-term measurement of volumetric...

The thesis discusses settlement relics and other traces of landscape use in sandstone bedrock of northern Bohemia from medieval ages up to 1st half of the 20th century. Three polygonal areas of interest covering an area of 1 km2 each were selected: area of hamlet Lešnice in the region of Roverské skály, area of Truskavna village in the region of Kokořínsko and area of Podkost village in the Český ráj region. The thesis compares these area and types of object found by field survey from 2015 and 2017-2019. It includes a detailed listing of documented objects, plans of chosen sites and detailed maps for each polygon. Keywords sandstone, field survey, small monuments, rock dwellings, Middle Ages, Modern period, everday life

Moisture in a sandstone body plays a notable role in hydrological, weathering, biological and other processes. Knowledge about presence and movement of moisture within porous medium of natural sandstone exposures is, however, rather limited. Aim of the doctoral thesis was thus to quantify selected moisture characteristics of several natural sandstone exposures in Český ráj (Czech Republic). According to long-term logging, mean annual temperature at studied areas was between 8.5 řC to 11.5 řC, mean annual relative humidity was between 73 % to 85 %. Deforested area was found warmer and drier and amplitude of the values was higher there than at the forested areas. Values of water content (more than 400 measurements) and suction (more than 150 measurements) of the exposures including their spatial-temporal changes were obtained. Mean volumetric water content in zone from the sandstone's surface to 12 cm depth was from 3 % to 10 % and mean suction in depth 2-12 cm was from 2 kPa to more than 130 kPa. Using uranine powder coloring, spatial distribution of moisture near the sandstone's surface was visualized repeatedly for the first time. The coloring divided the surficial area of the sandstone into capillary (wet) and diffusion (dry) zone. The sharp transition between the two zones was represented by...

This paper introduces the application of an effective crack model to analyse the response\nof chevron-notched cylindrical specimens loaded in three-point bending. There were\nanalysed the three sandstone specimens from the Javorka locality and three concrete\nspecimens from the building structure of the Ostrava-Vítkovice railway station. The\nchevroncylinder software based on the finite element method was used for the\ncalculations.

The Eastern Bohemian Skála Castle located in Adršpach-Teplice Rocks belongs to a wide group of manors with not yet formulated questions. The aims of the paper are both criticism of a few current reconstructions of the manor and raising questions after the relict evaluation.

The article presents an analysis of degradation processes and partial results of an experimental research into materials and structures exposed to the effects of external environments with an emphasis on the effects of moisture and chemical degradation processes on major mechanical properties of sandstone.

The purpose of this work is the processing of enviromental education together with nature and interpretive trails protection. Then the work deals with interpretive trails analysis in Labske piskovce PLA and the new design of interpretive trails in this location. The most frequent problems of these paths are their marking, length and route location. The design of the new interpretive trails should eliminate all the problems. The trail was designed so that most visitors could get closer to the surrounding countryside and was available for them as well. The benefit of this proposal could be an economical increase of the district thanks to the influx of new tourists.

Cílem této práce bylo orientačně otestovat, do jaké míry je rozpad díky vzduchu stlačovanému kapilární vodou nasávanou do sedimentu (kapilárně-pneumatický rozpad, KP rozpad) významným procesem při erozi různých sedimentů, jako jsou písky až slabě cementované pískovce, spraše, jíly, jílovce a případně i jílovité půdy. Dílčím cílem bylo především vytvořit a na několika vybraných materiálech otestovat jednoduchou metodiku, prokazující, zda sediment podlehne KP rozpadu, dále vypočítat destrukční tlak daný KP rozpadem v pórech sedimentu a porovnat ho s tahovou pevností materiálu a konečně posoudit vliv mineralogie a porosity sedimentů na KP rozpad. Pro odlišení KP rozpadu od jiných destrukčních procesů jsem zvolila pozorování rozpadu dvojic vzorků, kdy jeden byl saturován za běžného atmosférického tlaku vzduchu a druhý ve vakuu. Tato metoda je schopná odlišit KP působení od jiných erozních procesů a zároveň je přiměřeně rychlá a vhodná pro různé sedimenty a zeminy. Pozorování potvrzuje, že KP působení je schopno rozložit různé sedimenty a zeminy na jemné částice, jedná se o velmi důležitý proces rozpadu, který probíhá i ve stojaté vodě, může být iniciátorem pipingu a měl by být proto intenzivně studován. Srovnání vypočtených hodnot pórového tlaku s tahovou pevností ukázala, že vypočtené pórové tlaky...

Title: Destroying of rocky shapes caused by climbing Objectives: The main aim of this bachelor thesis is find out a rate and type of damage sandstone rocky shapes casused by climbing. This bachelor thesis is also engaged in climbing and its relationship to nature conservation in the snadstone landscapes. Methods: For the theoretic part of this bachelor thesis was used a method of analysis of documents and available literature. For the research section of this thesis has been carried out field research in choosen districts by observation and taking a photographs of type of damage sandstone rocky shapes. Results: We found out a shapes and rate of damage sandstone rocky shapes in choosen districts. The rate of damage of sandstone rocky shapes depends on the rate of climbing. We also found out that damage of sandstone rocky shapes are influenced by other sports and recreational activities. Keywords: climbing, geomorphology, anthropogenic geomorphology, sandstone, sandstone landscape, protection of the nature

The thesis deals with moisture transport in porous medium of quartz sandstone. Capillary water and its movement is crucial for processes such as salt and frost weathering, growth of organisms and development of honeycombs and tafone. However, moisture transport is still not well described. I focused particularly on two new methods applied to sandstone investigation. In the laboratory I studied moisture transport in sandstone samples by means of repeated injection of uranine solution. I observed the evolution of evaporation front based on the changes in solution concentration indicated by difference in color of uranine solution. Additionally I investigated moisture content in the shallow subsurface of sandstone outcrops in the field using suction pressure and moisture content measurements by microtensiometers and TDR in three locations in the Bohemian Cretaceous Basin. Uranine proved to be an excellent tracer for visualization of the evaporation front geometry and its evolution in time. The results suggest that moisture transport is considerably affected by the presence of biofilms which are hydrophobic and retain moisture transport to surface. In addition, the values of suction pressure measured in honeycombs and a tafone are in agreement with the salt weathering model proposed by Huinink et al. (2004).

As a result of ground water pumping in the Střeleč quarry there has been developed a depression in ground water surface during recent 30 years impacting an area of approx. 10 km2 . Due to the existence of steep hydraulic gradient in the quarry surroundings subsurface erosion occurs resulting in a development of underground channels. The biggest one developed in the years 2000 - 2002. Its length was 300 m reaching in some place the height of 17 m. During field works in the quarry in the years 2009 - 2010 the only accessible channel was mapped. In the channel two main types of cracks were discovered. On the crossing of these cracks slumping of the sandstone occurs which causes difficulties for the mining company. A hydraulic gradient higher than 5% was determined to be critical for sand transport in the channels and widening the initial conduits into channels. The channel development and releasing of static ground water reserves also influenced chemical composition of ground water emerging in the quarry. In the period of the most intensive channel development in 2001 the ratio of ground water from static reserves on the total amount pumped was 56%. Also in this period the concentration of sulphates in the ground water of the streams in the quarry decreased significantly. In the year 2010 there were...

Summary: In my thesis I reviewed the most used methods for moisture measurements with the focus on sandstone exposures. Concerning direct methods, the gravimetric is used most commonly for the calibration of other methods. Concerning indirect methods I mention radiometric, microwave, resistive and capacity methods. The major part of thesis is dedicated to capacity device TDR (Time Domain Reflektometry), which emits electromagnetics pulses and measures the reflection time at the beginning and the end of the probe. This methodology is nondestructive and is widely used, mainly in pedology. In practical part of Theses I worked with drill cores of sandstone from natural exposures and I detected their mass water content using gravimetric method, their bulk density by laboratory measurements and from those values I calculated volumetric water content. Average value from measured mass water content is 3,3% and from volumetric water content 6,2%. At some localities the moisture content was measured by TDR was measured beside taking drill cores At places where it was possible to compare measurements using TDR with gravimetric method, TDR measurements show usually higher values (in average 1% higher) then gravimetric method. This fact is caused by calibration and accuracy of the device, generally though this TDR...

Aim of this study was to describe capillary water and vapor transport in shallow subsurface of Hrubá Skála sandstone in the Bohemian Paradise. I have quantified permeability of Hrubá Skála sandstone for water vapor using "wet cup" method and also capillary water absorption of sandstone drill cores. I have found out general rules of evaporation and rate of evaporation from several sandstone outcrops in real microclimate. Important part of my work was to determine whether surface crust plays some role in studied parameters. Based on my results, permeability of different types of sandstones for water vapor does not vary significantly and surface crust has no effect on rate of water vapor diffusion. Rate of capillary water absorption is reduced by surface crust. Hrubá Skála sandstone is classified as medium or highly absorbing material. I have proved that evaporation from porous medium can be approximated by exponential function. Rate of evaporation is strongly controlled by climatic conditions, especially by relative humidity. Powered by TCPDF (www.tcpdf.org)

Large depression cone in water table was formed due to mining in surroundings of Střeleč quarry. The concentrated inflow from conduits to quarry is up to 70 l/s. Large conduit systems are created by flowing water into the quarry. The biggest conduit system was at least 300 m long and 17 m high with maximum calculated volume of 22 thousands m3 . Evolution of these conduits usually takes several months to few years. Fast conduit evolution allows to study erosion processes in detail in situ. In the thesis I am describing conduits, character of flow and erosion processes. Measured flow velocities in conduits are up to 0,4 m/s with hydraulic gradient 1 to 5%. Flow velocities and hydraulic gradients are typical for piping erosion. Piping initially forms small protoconduits. The bigger conduits are formed as water is progressively drained from larger area. Conduits are following fracture surfaces, which are also limiting the conduit propagation to the sides. Above water table the conduits are enlarged mainly by mass wasting of undercut sandstone slabs. For distinguishing less and more erodible parts of sandstone, we adapted and partially developed a method for measuring erodability (REI) and drilling resistance (DR). Both are used to compare different types of sandstone surfaces. In lowermost part of the...

This PhD thesis contains the results of comprehensive research into the Pravčická brána Arch and surrounding sandstone massifs with focus on gaining more knowledge about natural dynamics and evolution of this rock formation, its current level of stability and the weathering processes it displays. Non-destructive methods were used for this comprehensive study; these ranged from detailed field documentation to monitoring temperature regime of the rock and included application of a geophysical survey and control monitoring of the course of arch body deformation. Laboratory testing was carried out for strength parameters and salt efflorescences together with weathered sandstones were analysed for chemical compounds. Main operating factors were monitored simultaneously, which particularly involved changes in external temperature, degree of sunlight and chemical composition of rainfall. Conventional as well as entirely new assessment procedures were used in synthesis and interpretation of the data collected, including knowledge of nonlinear dynamics of complex systems. The survey was designed to fully respect the protective conditions of the site, to make follow-up activities possible in future and to monitor any possible negative changes in the rock massif. The main results incorporate description of...