Mrákotínská žula kamenolomu Horní Dvorce - vlastnosti, využití, výzkum

In this paper, the authors inform readers about the operation of the Horni Dvorce Quarry exploiting the Mrakotin-type granite. The paper further summarizes the properties and utilization of the mined raw material. The reader is also familiarized with the parameters of research being currently in progress in this quarry. This is the research on mechanical properties of granites of Mrakotin type using various types of explosives to produce products of coarse and fine stone production.V tomto příspěvku autoři seznamují čtenáře s provozem kamenolomu Horní Dvorce, který těží žulu mrákotínského typu. Článek dále shrnuje vlastnosti a využití těžené suroviny. Čtenář je též seznámen s parametry výzkumu, který na tomto kamenolomu v současné době probíhá. Jedná se o výzkum mechanických vlastností žul mrákotínského typu při použití různých druhů trhavin k produkci výrobků hrubé a ušlechtilé kamenické výroby

Effects of cyclic loading on the rheological properties of sandstones

This paper presents some results of the laboratory tests on the time-dependent behaviour of three types of sandstone. Research into the rheological properties of rocks is mostly done under static (quasistatic) loading. In nature, however, rocks are also often subjected to cyclic (vibration) loading as a result of vibrations from traffic or the propagation of seismic waves due to, for example, earthquakes, rock bursts, blasting operations and such like. On this account, the research presented is focused on the study of rheological rock properties during vibration (cyclic) loading. The tests of the rheological properties of a cyclic load were conducted both in creep regime and in relaxation regime, at various levels of average load or strain and for various parameters of vibration (frequency, amplitude). The measured values of different parameter settings were compared and evaluated so that it was possible to set the dependence of cyclical rock loading in the rheological regime. For the purpose of the comparison of rock behavior during vibration and static loading, other tests were also carried out. The results of the research show that, in the course of cyclical loading, the rock rheological properties depend, to a significant extent, on the parameters of this loading, especially the amplitude and frequency.Web of Science3221420

The advance of mining in the quarried space mokrá I at Karlovy Vary - a study

Import 31/07/2007Prezenční542 - Institut hornického inženýrství a bezpečnost

Research of Mechanical Quality Granites of Mrakotínský Type While Using Different Kinds of Demolitions to Performance Products of Coarse and Noble Earthenware Production.

Import 11/04/2012Cílem dizertační práce je výzkum a vyhodnocení mechanických vlastností ţul mrákotínského typu při pouţití různých druhů trhavin k produkci výrobků hrubé a ušlechtilé kamenické výroby a řešení otázky moţných alternativ pouţití trhavin a konstrukcí náloţí při těţbě bloků horniny a při sekundárních trhacích pracích, pouţívaných k přípravě suroviny určené ke zpracování na produkty hrubé a ušlechtilé kamenické výroby. Zkoumány byly mechanické vlastnosti horninových vzorků, zejména pak tlaková pevnost a přetváření horniny do meze pevnosti. U zkušebních tělísek byla provedena zkouška v prostém tlaku a stanovení přetvárné charakteristiky horniny do meze pevnosti. Na základě výsledků měření byla stanovena optimální volba trhaviny, konstrukce náloţe a ideální poměr hmotnosti náloţky trhaviny k ploše lomu vzniklé po rozpojení bloku.Content of dissertation is research and evaluation of mechanical quality Mrákotín granite type while using different kinds of demolitions to performance produce coarse and noble earthenware production and solving problem possible alternatives of using demolitions and construction charges at mining rock blocks and at secondary blasting operations used to disposition of raw materials determined to fabrication into produces coarse and noble earthenware production. Investigated were the mechanical properties of rock samples, especially compressive strength and deformation of rocks breaking strength. The test particles were tested in unconfined compression and fixing deformational characteristics of rock in tensile strength. Based on the results of the measurements was determined the optimal choice of expolosive sort, design of the explosive charge and ideal ratio of weight blasting cartridges to surface fracture formed by disconnection the block.Prezenční542 - Institut hornického inženýrství a bezpečnostivyhově

Granite extraction at the Horní Dvorce stone quarry

Import 23/01/2008Prezenční542 - Institut hornického inženýrství a bezpečnostiNeuveden

Research results of geotechnical properties of soils at the Podkrušnohorská výsypka dump in Sokolov brown coal field

Open pit brown coal mining in the Sokolov coal field has been suffering with the lack of a space for overburden rocks dumping from its very beginning. The Podkrušnohorská výsypka dump is situated in a geomorphologically highly broken landscape at the Krušné Hory Mountains foot and northern part of Sokolov Basin divide. Dump rock consists of tuffaceous clays vith minimal specific resistance values QST = 0.5 - 1.0 MPa and cypric clays with minimal specific resistance values QST = 1.0 - 2.0 MPa. Large scale research works took place on the dump in various periods of time. The mining solutions of the methods on the dump were subjects of stability expert’s statements. 23 statements were produced sequentially from 1966 which were aimed to both general slopes of whole the dump and partial issues on the dump during its foundation. The dump was the scene of the series of landslides, most important of them were in the years 1986/1987 and 1990. Hydro-geological and geotechnical research was the base for stability reports and it concentrated in the dump bed quality, dump water bearing, bed water bearing, and to obtaining geotechnical parameters dump bed and dump rock fill. Basic physical and descriptive strength, transformation and technological parameters were established by in situ and laboratory tests. A long term geotechnical monitoring has been taking place on the dump – ground water level measurement, penetration measurement, dump body pore pressure measurement, inclinometric measurements in the drills, and geodetic observation of surface points of the dump.Web of Science18315715