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Laboratory research on stiffness of unsaturated soil in very small and small strain region
Mohyla, Tomáš ; Boháč, Jan (advisor) ; Herle, Ivo (referee) ; Panuška, Jakub (referee)
Unsaturated soils have come into focus of the geotechnical community in recent decades. They are commonly found in the interaction of structures with the geological environment. Laboratory tests are important to provide information on the behaviour of unsaturated soils and as a fundamental input for the design of engineering structures. Laboratory tests can also be used to design and calibrate numerical models describing the behaviour of unsaturated soils. One of the important input parameters of such models is the initial stiffness of the soil and its decrease with increasing strain. This thesis deals with a laboratory investigation of the stiffness of unsaturated soil in the regions of very small and small strains. The tested soil was a loess from the quarry near the village of Horky nad Jizerou, Central Bohemia, which represents a typical soil found in engineering practice. The soil was reconstituted for the purpose of laboratory tests. The maximum (initial) stiffness of the soil was determined from measurements using piezoelectric bender elements and the stiffness decay curves were measured using local strain transducers (LVDTs). The laboratory tests were carried out in a double-walled triaxial cell for unsaturated soils, mounted with a high air-entry value ceramic disc (HAEV). The triaxial...
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Identification and Comparison of Selected Physical Fitness Parameters in Members of the Integrated Rescue System
Miřátský, Petr ; Zahálka, František (advisor) ; Přívětivý, Lubomír (referee) ; Pivovarniček, Pavol (referee)
Title: Identification and Comparison of Selected Physical Fitness Parameters in Members of the Integrated Rescue System Aims of the thesis: The main aim of this thesis was to identify the level of selected indicators of physical performance or physical fitness in members of selected Integrated Rescue System (IRS) units. Another aim is to objectify the determinants in order to clarify the achieved performance with subsequent comparison between selected IRS units. Within the Fire and Rescue Service (FRS) component to identify and highlight the type of physical training with the greatest effect on the level of selected physical fitness parameters. Methods: In the present study, selected parameters of body composition (Tanita MC-980MA), postural stability (RS Footscan), flexibility (Sed and reach), isometric muscle strength of upper and lower limbs (Groinbar), isokinetic strength of knee flexors and extensors (Cybex Humac Norm), dynamic strength of lower limbs (Kistler) and selected parameters of aerobic fitness (Cortex Metalyzer 3B) were evaluated. The body composition parameters assessed were: body fat (%), fat mass (kg), muscle mass (kg), muscle mass distribution (kg) and BMI (kg-m-2); postural stability: total center of compressive force (mm); flexibility: reach (cm); isometric strength: maximum...
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Dubičná landslide - engineering geological mapping and Atterberg limits
Vavřich, Lukáš ; Jerman, Jan (advisor) ; Routner, Martina (referee)
This bachelor's thesis addresses the issue of slope deformations in the České Středohoří region and closely examines the landslide at the Dubičná site. In the late 1960s, significant slope deformations occurred here, endangering a railway embankment and the road beneath it. The landslide is situated in a geologically complex terrain where manifestations of Tertiary volcanism intersect with sediments from the Bohemian Cretaceous Basin. Due to the geological history, the broader vicinity of the studied area features numerous slope deformations with the potential to cause property damage and threaten human lives. Detailed field mapping was conducted in the landslide-prone area, resulting in the creation of an engineering-geological map of stability conditions. This map, utilizing modern remote sensing technologies, intricately depicts the progression, morphology, and shape of the landslide. Soil samples were also collected, and following prescribed laboratory procedures, their index properties were measured, including liquid limit and plastic limit moisture content. Based on the results of these measurements, the presence of a deformation zone within the landslide was estimated to be at a depth of approximately 5.5 meters.
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Correlations of parameters of selected rock types based on laboratory tests
Závacký, Martin ; Lahuta, Hynek (referee) ; Durmeková,, Tatiana (referee) ; Horák, Vladislav (advisor)
The dissertation thesis deals with the properties of hard rocks important for designing geotechnical structures, such as strength and deformation characteristics, as well as rock failure criteria. This work examines the possibility of using correlation relations to estimate the strength characteristics of rocks from index tests, which can make the rock testing process more efficient. The author described selected laboratory tests of rocks and identified several limitations of the tests procedures based on his own practical experience. The correlation analysis of an extensive data set and the derivation of regression relations for selected dependencies were performed. Furthermore, the rock strength estimation quality of the newly derived regressions was compared with the already published regressions. The analysis shows that the achieved degree of correlation is not sufficient to generalize the examined regressions. A significant reason of the low degree of correlation is the combination of the variability of rock properties and limitations of practical testing procedures. Thus, focus should be paid on calibration of the regression relationships within smaller areas in order to precisely estimate the rock properties as reliable input to the geotechnical design.
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Use of R-material in asphalt mixtures with highly modified binder (HiMA)
Christ, Roman ; Dašek, Ondřej (referee) ; Hýzl, Petr (advisor)
The subject of this diploma thesis is paid attention to the influence of different dosing of R-material containing unmodified asphalt on the properties of asphalt concrete for abrasive layers (AC011 +) bonded with polymer highly modified asphalt (binder type HiMA). The properties of asphalt mixtures will be evaluated by means of the stiffness modulus test and the test of low-temperature properties by a uniaxial tensile test.
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Social cognition in birds Testing under laboratory conditions
Vondráčková, Nikola ; Nekovářová, Tereza (advisor) ; Fuchs, Roman (referee)
The thesis focuses on avian social cognition and its experimental methods in laboratory environment. Social cognition is the ability to know each other based on individual experience. Perception, attention, reasoning, memory and communication are the necessary cognitive competence of social cognition. Some cognitive domains are exclusively in social cognition - for example communication, theory of mind etc. Species of birds living in social groups constitute the social environment in which individuals respond to each other. Research subject of this thesis consists of these social interactions. Emphasis is placed mainly on parrots and corvids. The aim of this study is to review methods which have been used in order to test social cognition as well as critical evaluation of these methods. Key words: social cognition, cooperation, competition, laboratory tests
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