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The thesis deals with an application of the geotechnical numerical back analysis and several other geotechnical conventional techniques in estimating the thickness of eroded sediments. Investigated strata is the Lower Miocene marine clay, often called "Tegl" which was deposited in the Carpathian Foredeep in the eastern part of the Czech rep. Numerical back analysis is based on an assumption that erosion thickness of a soil can be derived from its stress sate represented by K0 coefficient (coefficient of earth pressure at rest). The erosion thickness given by the numerical back analysis is compared with two estimations using Baldwin-Butler's equation and Casagrande's concept of preconsolidation stress. The erosion thickness is also derived from K0 values given by two field probes: Flat dilatometer (DMT) and Push-in spade shaped pressure cell (PSPC). The numerical back analysis was applied to galleries and adits opened during site investigation of the Královo Pole Tunnels in Brno. Both the samples for laboratory analyses were taken and the field tests were carried out in area of Brno city. Discrepancy of the results is analyzed and the conclusion is that the results given by the four conventional mentioned techniques (Baldwin-Butler, Casagrande, DMT, PSPC) are strongly distorted if the investigated...

This Thesis deals with the determination of shear moduli of Brno Neogene clay ("tegel") in various directions and the determination of its stiffness anisotropy. The basic measure of stiffness anisotropy in this thesis is considered to be the degree of anisotropy αG given by the ratio of shear moduli in the horizontal (Ghh) and vertical direction (Gvh). Measurements of shear wave velocity were performed on undisturbed vertically and horizontally oriented samples of the Brno tegel in triaxial cell using piezoceramic sensors, so-called bender elements. As an advanced method for determining the degree of anisotropy of the material, another pair of bender elements was used in the measurements, mounted horizontally on the side walls of the sample in the triaxial cell. Based on these measurements, the values of shear moduli Ghh and Gvh for different stress levels were determined. The ratio of shear moduli then determined the degree of anisotropy αG ≈ 1,43 for the given stresses, as the most reliable value based on performed experiments. Literature review part of the thesis briefly summarizes the existing findings from research of physical and mechanical properties of the Brno tegel.

This thesis deals with the dam of the Šeberák pond. This water reservoir is included in III. category of historical water works. The dam is currently showing minor defects, but could be seriously damaged by extraordinary circumstances. The aim of this thesis is to accomplish an engineering geological survey of the dam, to assess its competence and recommend remediation measures. For the purpose of the survey, core boreholes and dynamic penetration tests were performed. Soil samples were taken from the drilling cores for laboratory soil tests. Geomorphological, geological and hydrogeological conditions were described, one longitudinal geological section of the dam and four cross-sections were constructed. Based on evaluated field works and obtained data from the pond manager, the engineering geological conditions of the dam body were described. The most serious concern is the intensity of water seep throught the dam in flood situations. Solution options have been recommended for each part and problem of the dam.

The Bachelor thesis deals with some tunnels from the total number of 120 railway tunnels build in the period 1848-1910 in the territory of the Czech Republic. The aim of these admirable buildings was the research for masonry, geology and rock strength. The introductory articles are devoted to the classical tunneling methods used in earlier times. As a result of today's higher operating speeds of trains, which was not taken into account when initially planning the lining and limitation to the use of stone and wood only. The work includes the most frequent reconstruction methods for tunnel optimization, the possibility of faster transport and their stability. It has been shown that, for the purpose of possible reconstruction, it is necessary to count on the considerable strength of the masonry which, even after 100-170 years, often does not show signs of deep degradation.

This paper discusses impressive project of the tunnel between Prague and Beroun. The length of the structure, spreading up to 25 km, leads to need of overcoming many risks, which may the tunnel encounter. The text is focused on specific issues typical for areas built by karstic rocks, which generally present one of the most dangerous environment for building architectural projects of any kind. It concentrates on description of Bohemian karst and karstic features, which are likely to appear in studied area. It strives for delimintion of risks and suggestion of proper investigtion and remedition methods, suituable for given project. A part of the paper is a brief introduction into main tunneling technology, applicable for tunneling construction and discussion of possibilities of particular tunneling method.

This bachelor thesis deals with groundwater aggressiveness on two sheets of detailed engineering geology maps of Prague 1:5000. The aim of this thesis is an effort to verify how much geological environment of inner Prague participates in chemical composition of groundwater. The chemical analysis were evaluated using limit values stated in valid norm ČSN EN 206 Concrete - Specification, performance, production and conformity. The chemical analysis that analyzed aggressive components (SO4 2- , CO2 a pH) and total dissolved solids discovered that the geological environment affect the chemical composition of groundwater very strongly. Groundwater in Ordovician shale commonly contains high amount of dissolved solids with a lot of sulphate. In geological environment containing quartzite, greywacke, quartz and greywacke sandstone the groundwater has small amount of dissolved solids and no aggressive component is dominant as well as too high compared to the shale.

This work looks into geotechnical conditions in Vodochody Airport area. In this work research into available literature, sampling and laboratory processing of the samples were conducted. Based on the results of laboratory examinations, evaluation of suitability of the tested materials from the viewpoint of corresponding standards was accomplished. Three geological cross sections were also constructed. Basic classification analysis and additional tests after ČSN 73 6133 (2010), Chapter 4 were conducted. Both archival documentation and tests results prove significant variability of geological setting in the area of interest. The work describes current unsatisfactory state of the airport's runway and proposes one alternative of reconstruction. Foundation conditions of further constructions are also considered. Lastly the work points out several problems which may occur in the area and presents findings that will need to pay attention to in case of further exploration.

Negative pore pressure (suction) in soils can be measured by various methods. Probably the most precise way is using the 'Imperial College suction probe', which is briefly described, was however not available. A simple alternative is represented by the filter paper method. It was used to determine the suction in the undisturbed samples of the overconsolidated Miocene clay from the town of Brno (Brno Tegel). However the capillary suctions determined by the filter paper were unrealistically high, and could not be used in estimating the in-situ horizontal stresses (at rest coefficient K0) in the Tegel. The reasons for the failure are discussed and possible future steps are suggested.