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Mechanical properties of basalt: a study on compressive loading at different strain rates using SHPB
Falta, J. ; Krčmářová, N. ; Fíla, T. ; Vavro, Martin ; Vavro, Leona
This article focuses on the mechanical properties of basalt in compressive loading at different strain-rates. The study employs advanced instrumentation for the evaluation of the results in dynamic conditions, while standard uni-axial loading device is used for evaluation in quasi-static conditions. Basalt specimens were subjected to four different loading-rates from 200–600 s−1 on which the stress-strain dependence was evaluated together with DIC analysis of crack initiation and disintegration process. Understanding the mechanical properties of basalt can provide insights for engineers and designers in creating structures that are durable and able to withstand different loading conditions. The findings of this study can have implications for a wide range of industries, including aerospace, automotive, and construction, among others.
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Effect of aggregate type on lime mortar rheology
Vozák, Rastislav ; Rovnaník, Pavel (referee) ; Vyšvařil, Martin (advisor)
The subject of this bachelor thesis is examining the effect of aggregate type on lime mortar rheology. In the theoretical part, the thesis describes types of liquids and basic rheological quantities. Afterwards there are described some of the rheological behaviour models of non-Newtonian fluids. Furthermore, the theoretical part characterizes measurement of the flow, devices used for the measurement including the oscillatory measurement and its individual modes. Scientific literature was used to describe the rheology of the lime mortars and it covers the effect of different additives on the rheological behaviour. There is also characterized the effect of aggregate on the properties of lime mortars. The experimental part talks about the effect of three various kinds of aggregate on rheological prop-erties of the fresh lime mortar. The chemical composition of aggregates and their granulometry was determined. Subsequently, flow measurements were carried out and evaluated into flow curves. The yield stress, coefficient of consistency and flow index were assayed. In the oscillatory measurement there were measured complex, elastic and viscous modulus and loss factor.
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Petrografická identifikace vulkanické horniny z vrchu Větrovec u Vysoké Lípy v NP České Švýcarsko
Adamovič, Jiří ; Mészárosová, Noemi ; Mikysek, Petr
Byla provedena petrografická analýza dvou vzorků vulkanitů odebraných z intruze v pískovcích jizerského souvrství na jihozápadním svahu vrchu Větrovec, kat. Vysoká Lípa. Pomocí optické mikroskopie, fázové analýzy metodou práškové rentgenové difrakce a bodových kvalitativních analýz jednotlivých minerálních fází na elekronovém mikroskopu s EDS detektorem byly popsány jednotlivé minerální fáze v obou vzorcích a zjištěny jejich obsahy a vzájemné vztahy. Hornina vzorku 1 je rhönitický olivinický bazalt s možnými přechody do rhönitického nefelinického bazanitu, hornina vzorku 3 je vesikulární rhönitický olivinický bazalt.
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Volcanism of Large Igneous Provinces in Earth's history; possible impacts on global ecosystem
Zajícová, Jana ; Holub, František (advisor) ; Rapprich, Vladislav (referee)
Large igneous provinces (LIPs) are huge accumulations of magmatic rocks originated during unusually short time and characterized by extremely high magma productivity. Among them, namely the continental flood basalts (traps) cover very extensive areas and may or may not be associated to rifting and breakup of continents. However, also highly voluminous oceanic plateaus were recognized and some authors count to LIPs even some other types of huge magmatic complexes. A large amount of gases is released with escaping magma, usually oxides of carbon, sulfur and nitrogen. These gases more or less have impact on the environment and thus also influence organisms. The formation of magmatic provinces repeated many times in the past. The best known are continental Deccan Traps in India and the most voluminous Siberian Traps. Oceanic LIPs are represented, e.g., by the Ontong Java Plateau in the west Pacific Ocean. There is a link in dating the emergence of large igneous provinces and mass extinctions. As an example, the largest known extinction at the end of Permian, which was broadly contemporaneous with the formation of the Siberian traps (approximately 250 Ma ago), or extensive loss of species on the boundary of Cretaceous / Tertiary, which coincides with the formation of the Dekkan in India (before about 65...
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Paleomagnetic record of basaltic lava flows on Nelson Island, Antarctica
Haislová, Radka ; Kletetschka, Günther (advisor) ; Pruner, Petr (referee)
Paleomagnetism is geophysical method for determination of former magnetic field orientation on the Earth using measurement of remanent magnetisation of rocks. Combined with radiomagnetic datingk paleomagnetism enables study of time evolution of the magnetic field on the Earth and/or reconstruction of former positions of litospheric plates. This thesis is elaborates on paleomagnetic record of basalt lava flow on the Nelson's Island in Antarctica and summarizes geological data. In the research part of this thesis theory of magnetism is introduced and the paleomagnetism method is emphasized. Additionaly, I provide a short review of magnetic minerals, that can occur in basalt. These mineral can potentialy hold some information about the character of magnetic field of the geological past. Radiometric dating methods are included as atool for determination of absolute age of solidification of ingenous rocks (lava). Specifically, the K-Ar and Ar-Ar dating methods are emphasized. The regional section of this thesis conntains geological overview about the Antarctica and the Nelson's Island with its surroundings.Included is a section about the laboratory devices for measuring vector magnetisation of oriented rock samples (for example rotational and cryogenic magnetometer). The thesis is concluded with its...
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Effect of aggregate type on lime mortar rheology
Vozák, Rastislav ; Rovnaník, Pavel (referee) ; Vyšvařil, Martin (advisor)
The subject of this bachelor thesis is examining the effect of aggregate type on lime mortar rheology. In the theoretical part, the thesis describes types of liquids and basic rheological quantities. Afterwards there are described some of the rheological behaviour models of non-Newtonian fluids. Furthermore, the theoretical part characterizes measurement of the flow, devices used for the measurement including the oscillatory measurement and its individual modes. Scientific literature was used to describe the rheology of the lime mortars and it covers the effect of different additives on the rheological behaviour. There is also characterized the effect of aggregate on the properties of lime mortars. The experimental part talks about the effect of three various kinds of aggregate on rheological prop-erties of the fresh lime mortar. The chemical composition of aggregates and their granulometry was determined. Subsequently, flow measurements were carried out and evaluated into flow curves. The yield stress, coefficient of consistency and flow index were assayed. In the oscillatory measurement there were measured complex, elastic and viscous modulus and loss factor.
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Factors influencing vegetation establishment during spontanous succession in basalt quarries
Petrů, Anna ; Frouz, Jan (advisor) ; Roubíčková, Alena (referee)
Mining and construction industry is a major environmental disturbance creating habitats with extremely coarse material: gravel, cobbles and boulders. Simultaneously, there is an increasing interest in using spontaneous succession during restoration processes on those areas. This leads to a question if vegetation can establish on such coarse substrates. This project assessed the vegetation establishment on substrates with different grain size as well as the hydrological limitations of those substrates. The aim of this study was to find substrate moisture characteristics supporting vegetation establishment. Four herb species (Koeleria macrantha, Epilobium angustifolium, Artemisia campestris var. campestris and Poa nemoralis) typically occurring on xerothermic basalt rocks were sowed on basalt construction aggregates (0-4, 2-4, 4-8, 8-16, 11-22 and 32-63 mm). There were also made mixtures of coarse aggregates (4-8, 8-16 and 11-22 mm) as a base with 10% or 50% additive of fine aggregates (0-4 mm). The final number of individuals, aboveground and belowground dry biomass were measured and subsequently specific leaf area (SLA) was calculated. They were also measured substrate moisture characteristics: field capacity (PVK) and wilting point (BV) from which available water content (ODV) was obtained as...
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