National Repository of Grey Literature 42 records found  1 - 10nextend  jump to record: Search took 0.01 seconds. 
Authentication of real rock mass field voltage to increase safety in anomalous stress states
Koníček, Petr ; Staš, Lubomír ; Ptáček, Jiří ; Kaláb, Tomáš ; Chura, Jan ; Souček, Kamil ; Waclawik, Petr
Voltage fields are one of the key factors that, decisively, along with the mechanical and remodeling properties of rocks, greatly influence the behavior of the mountain massif. Knowledge of stress fields is beneficial for the design and successful implementation of geotechnical underground projects (eg for the assessment of the stability of underground spaces, the behavior of proposed reinforcements of underground structures, for space-time placement of underground structures) especially in non-trivial geomechanical conditions, both in terms of natural factors affecting stress fields structural and geological structure of the rock mass, tectonic stress, cracks and discontinuity in the rock mass) as well as anthropogenic factors (geomechanical configuration of the underground spaces and dynamics of their changes). Geotechnical practice in our (Czech) conditions is usually used only calculations of a voltage field based primarily on the theoretical behavior of the rocks and the assumed vertical geostatic pressure at a given depth. The development of possible progressive deformations of the stress field is then derived from the development of anthropogenic interventions into a relatively homogeneous massif. In fact, tension is also affected by close geological structures. The data obtained from the study of the magnitude, direction and change of stress in the mountain massif are a significant contribution in mathematical modeling where they can be used as input parameters to obtain a more accurate picture of the behavior of mountain massifs and underground structures in the subject areas.
Final research report to the project PB-2014-ZL-U2301-004-BUKOV
Souček, Kamil ; Vavro, Martin ; Staš, Lubomír ; Kaláb, Zdeněk ; Koníček, Petr ; Georgiovská, Lucie ; Kaláb, Tomáš ; Konečný, Pavel ; Kolcun, Alexej ; Králová, Lucie ; Kubina, Lukáš ; Lednická, Markéta ; Malík, Josef ; Martinec, Petr ; Ptáček, Jiří ; Vavro, Leona ; Waclawik, Petr ; Zajícová, Vendula
Bukov Underground Research Facility (Bukov URF) has been built as a test site to assess the properties and behaviour of the rock mass analogous to selected candidate sites. It is situated at a depth corresponding to the proposed storage depth of the final locality for the Czech Republic´s deep repository of high-level radioactive waste. Bukov URF is located in the Vysočina Region, the cadastral district of Bukov, approx. 3 km south-eastwards from the municipality of Dolní Rožínka. The underground research facility is placed approx. 300 m from the Bukov-1 shaft, namely on the level 12 of the shaft, at the depth of about 550 – 600 meters below the Earth’s surface. As for the regional geology, Bukov URF is found at the southern part of the Rožná uranium deposit, at the north-eastern edge of the Strážek Moldanubicum close to its contact with the Svratka Unit. The rock mass is composed of a relatively monotonous sequence of differently migmatized biotite gneisses to stromatic migmatites, continuing with amphibole-biotite to biotite-amphibole gneisses and amphiboles, with occasional fine intercalations of aplites, pegmatites or calc-silicate rocks (erlanes). Between 2013 and 2017 and within the complex geotechnical characterization of the Bukov URF, the Institute of Geonics of the Czech Academy of Sciences (Ústav geoniky AV ČR, v.v.i.) in Ostrava carried out a series of laboratory and field works in order to provide a detailed description of the geotechnical and geomechanical properties and quality of the rock mass. The works included the determination and assessment of the physical-mechanical properties of the rocks sampled from the walls, boreholes and ground surface in the locality, the determination of stress state and deformation properties of the rock mass using the methods of hydrofracturing of borehole walls, Goodman Jack and CCBO, or CCBM, determination of the rock mass quality based on selected index geomechanical properties, periodic, long-term strain-gauge measurements and convergence measurements, and the assessment of the effect of technical and mine-induced seismicity on the rock mass of interest. The implemented set of research works was supposed to render a sufficient and integral whole of geotechnical and geomechanical knowledge vital for the subsequent implementation of extensive research experiments focused on long-term safety and technical feasibility of the future national deep repository of radioactive waste.
Parametric study of usability of selected surveying equipment for monitoring of mine workings stability in undermined areas
Kajzar, Vlastimil ; Kukutsch, Radovan ; Koníček, Petr ; Waclawik, Petr ; Šňupárek, Richard
Although the deformation measurements are in mining practice routine activities, the development of information and surveying technology shows, that it is possible to approach this problematics in a new way. One of the options is the application of terrestrial 3D laser scanning technology, which can be successfully used both for purposes of monitoring - deformations of objects on undermined area and mine workings at all.\nSubmited parametric study presents the use of laser technology in the research activities of the Institute of Geonics, v.v.i., within the ICT-PU project. This study deals with technical and theoretical aspects of laser scanning, which verification in situ has been a precondition for the subsequent successful application of this technology both on the surface and in the mining environment. The main scope of the study is dedicated to the deployment of selected technology in solving specific tasks. In the undermined areas were achieved knowledge used in solving the problems of monitoring the stability of slopes and rock faces of mining chasm. In the underground mine workings, this technology has been successfully deployed for the purposes of the spatial deformation monitoring of selected longwall corridor at mine Karvina and also for the long-term monitoring of coal pillars in Room and Pillar pilot project at ČSM coal mine.\nAt the end of a parametric study is special space devoted to the limiting factors of 3D laser scanning and also to the summary of best practices of scanning in such highly exposed conditions.\n
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Partial Report IV / 2016 - Rating of the deformation stress monitoring the state of the rock mass during mining coal seam 30 (634) within the trial operation of mining method corridor - a pillar in OPJ ČSM - NORTH
Waclawik, Petr ; Ptáček, Jiří ; Kukutsch, Radovan ; Kajzar, Vlastimil ; Koníček, Petr ; Souček, Kamil ; Staš, Lubomír
Monitoring of the deformation stress state of the rock mass is a prerequisite for the verification of unapproved new mining methods hall-pillar and its further application in the Czech part of the Upper Silesian coal basin. This mining method is designed on the basis of experiences and practices that are verified in different natural conditions and depths below the surface and is therefore essential for the verification of conditions for the Czech part of the Upper Silesian Basin based on geotechnical monitoring. The present report is prepared on the basis of a contract no. 942/50/10, where the Institute of Geonics, v.v agrees to make periodic evaluation of monitoring data napěťodeformačního state of the rock mass. In accordance with the aforementioned agreement, the message is processed in the six-month period and continues in the interim report III / 2015 (Waclawik et al. 2015) passed buyers in April this year. Interim results of the geotechnical monitoring, such as the experience gained during the first conquest dobývky V show specifics of natural conditions in trial operation unapproved new mining methods hall-pillar.
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The study of the influence of the single entry and pillar mining method in seam No. 40 in Jan-Karel protective shaft pillar, location CSA Mining Plant 1 on Jan and shaft No. 2 downcast shafts and on the CSA 3 upcast air shaft, surface and surface objects
Ptáček, Jiří ; Kajzar, Vlastimil ; Koníček, Petr ; Kukutsch, Radovan ; Waclawik, Petr ; Jiránková, E.
The presented method single entry room and pillar solves the possibility of applying single entry room and pillar mining method, where roadheaders are used, newly in two variants. According to the first of them will be entries and intra-entries inundated with a time lag with fly ash mixtures. The second variant will be excavated only basic entries with a width of 6.8 meters. They will not be flooded. The purpose of the study is also adding calculations of potential and the expected impact of single entry room and pillar method on the surface and surface objects and also the expected impact on the shafts in Jan-Karel protective shaft pillar.
Monitoring project of the deformation stress state of the rock mass during mining coal seam 30 (634) within the trial operation of mining method corridor - a pillar in OPJ ČSM - NORTH - Quarrying II
Waclawik, Petr ; Koníček, Petr ; Ptáček, Jiří
This is a project monitoring of the deformation stress state of the rock mass during mining decant no. 30 (634) within the trial operation of new methods corridor - a pillar in the protective pillars jam CSM Mine, site Sever
Partial Report III / 2015 - Rating of the deformation stress monitoring state of the rock mass during mining coal seam 30 (634) within the trial operation of mining method corridor - a pillar in OPJ ČSM - NORTH
Waclawik, Petr ; Ptáček, Jiří ; Kukutsch, Radovan ; Kajzar, Vlastimil ; Koníček, Petr ; Souček, Kamil ; Staš, Lubomír
Monitoring of the deformation stress state of the rock mass is a prerequisite for the verification of unapproved new mining methods hall-pillar and its further application in the Czech part of the Upper Silesian coal basin. This mining method is designed on the basis of experiences and practices that are verified in different natural conditions and depths below the surface and is therefore essential for the verification of conditions for the Czech part of the Upper Silesian Basin based on geotechnical monitoring. The present report is prepared on the basis of a contract no. 942/50/10, where the Institute of Geonics, v.v agrees to make periodic evaluation of monitoring data napěťodeformačního state of the rock mass. In accordance with the aforementioned agreement, the message is processed in the six-month period and continues in the interim report II / 2015 (Waclawik et al. 2015) passed buyers in April this year. Interim results of the geotechnical monitoring, such as the experience gained during the first conquest dobývky V show specifics of natural conditions in trial operation unapproved new mining methods hall-pillar.
Bukov PVP underground research laboratory - geotechnical conditions of construction
Souček, Kamil ; Vavro, Martin ; Staš, Lubomír ; Koníček, Petr ; Ptáček, Jiří ; Waclawik, Petr ; Vavro, Leona ; Lednická, Markéta ; Kaláb, Zdeněk ; Šňupárek, Richard ; Vondrovic, L.
Bukov PVP Underground Research Laboratory (Bukov URL) is designed to be a test site for the evaluation of properties and behavior of the rock mass which is of similar type as selected candidate sites in the Czech Republic. It is situated at a depth corresponding to the proposed storage depth of the final locality for the national deep repository of high-level radioactive waste. The Bukov URL, the construction of which has begun in 2013, is situated in the southern part of the Rožná uranium deposit, at the northeastern periphery of the Strážek Moldanubicum close to its contact with the Svratka Unit. The rock mass is composed of relatively monotonous rock sequences primarily of a volcanosedimentary origin. They are currently represented, due to the subsequent tectonometa-morphic development, by migmatized biotite paragneisses up to stromatitic and/or oftalmitic migmatites, amphibole-biotite to biotite-amphibole gneisses, and amphibolites. The workings of the Bukov URL are situated on the level 12 of the Bukov-1 shaft, at the depth of about 600 m below the earth’s surface. The Bukov URL is still under construction and the research works by the consortium of several organizations – ÚJV Řež, a.s., Czech Geological Survey, Institute of Geonics of the CAS, v.v.i., and Arcadis CZ, a.s. - are carried out simultaneously. The research activities focus on a complex geological and geotechnical characterization of the rock mass of interest, which is vital for the realization of further research in situ. This paper briefly describes the technical solution of the Bukov URL and the process of its construction.
Vliv pojezdového ústrojí zemědělské techniky na utužení půdy
Koníček, Petr
The diploma thesis provides an overview of the soil, its composition and attributes. Then, it briefly describes causes of soil solidification and methods of soil cultivation, which eliminate the unwanted soil solidification. This thesis also gives an overview of agricultural tyres, their composition and compression systems. Furthermore, it describes undercarriages of combine harvesters and their advantages and disadvantages. In the practical part of this thesis, there were done laboratory and field measurements of soil solidification after being run over by combine harvesters with different contents of grains in the grain hoppers and using the combine harvester inclination. Subsequently, the measurements were compared and evaluated in terms of changes in the soil porosity.
Stress state rock mass monitoring ahead of longwall No. 371 202 at 2ndA block, Mine Plant 2, OKD, a.s
Waclawik, Petr ; Ptáček, Jiří ; Koníček, Petr ; Vavro, Martin ; Staš, Lubomír ; Souček, Kamil ; Kukutsch, Radovan ; Kajzar, Vlastimil
Generally, the accurate knowledge of the stress strain state of the rock mass in the neighbourhood of the mining galleries and underground openings is absolutely critical for their precise support designing, not only in the vicinity of them, but also at a greater distance from them if the phenomenon affecting the rock mass stress fields occurs. Measurement (investigation) of the rock stress is usually carried out by interpretation of the rock mass deformation processes, which can be relatively precisely observed and measured. The roadways are loaded not only by rock pressures in the front of the coalfaces but also by destress blasting realised in the overburden rock seam in the scope of the rockburst prevention. In addition, the rock stress distribution is influenced by old mining activities too, for example by abandoned coal pillars in the seams in overburden, respectively by goaf in the excavated seam. All of these factors can significantly affect the stress-strain behaviour of the rock mass around the mining works.

National Repository of Grey Literature : 42 records found   1 - 10nextend  jump to record:
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1 Koníček, P.
2 Koníček, Pavel
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