216 research outputs found
Development of natural underground ore mining technologies in energy distributed massifs
The object of research is the technology and facilities for underground mining of ores in the disrupted massifs. One of the most problematic places is the formation of man-made voids; which influence the occurrence and redistribution of stress-strain state (SSS) of the rock massif. Their existence in the earth's crust provokes the influence of geomechanical and seismic phenomena; up to the level of earthquakes.
The study used:
– data from literature sources and patent documentation in the field of technologies and facilities for underground mining of ores in the energy-disrupted massifs of substantiation of technological parameters of operating units;
– laboratory and production experiments;
– physical modeling and selection of compositions of solidifying mixtures.
Analytical researches; comparative analysis of theoretical and practical results by standard and new methods with the participation of the authors were performed.
The questions of seismogeodynamic monitoring of the SSS of the rock massif during the safe development of rock-type ore deposits are considered. The interaction of natural and man-made systems providing geomechanical balance of ore-bearing massifs is shown. Possibilities of controlling the geomechanics of a massif with filling of man-made voids with various solid mixtures and tails of underground leaching of metals from substandard ores are investigated. The typification of processes is given and the distinctive features of underground block leaching of metals from rock ores are formulated in the aspect of controlling the geodynamics of the massif. The principle estimation of the combined technologies with rationalization of use of the SSS of the rock massif for regulation of the sign and magnitude of stresses in natural and artificial conditions is shown. The conclusions about the effectiveness of the controlled interaction of natural and man-made systems; ensuring the geomechanical balance of massifs and the earth's surface in the area of subsoil development over a long period of time. The research results can be used in the underground development of ore deposits of complex structure of Ukraine; the Russian Federation; the Republic of Kazakhstan and other developed mining countries of the world
Improvement of filling systems for deep ore mine depth
Purpose of study – improvement of filling systems for deep ore mine depth.The studies have been undertaken for improvement of filling systems for deep ore mine depth and with purpose to increase the safety level of subsoil mining activities. A general method of determination of parameters for retention of drill drift stability, installed in the vicinity of a stope area down dip as well as along the strike of ore deposit
Development of principles of opening strength during underground mining
There have been analyzed fundament a land applied research work saimed at development, testing and manufacturing application of efficient technological plans for developing, supporting and maintaining underground workings. There has been found the evolution of scientific and production principles which underlie the technologies of supporting and maintaining underground workings. The analyzed ones have been evaluated. There have been found trends of principle development ranging from counteraction and counterbalance to contribution, removal and transfer of the high pressure energy concentrated aroundworkings
Development of the geoenergetic monitoring methodology during underground development of the ore deposits
The scientific and practical results of the investigations in the domain of the geoenergetic monitoring methodology have been provided. The method of investigation of the zonal destruction processes of the massif surrounding the underground excavations has been described. There sults of the shaft, laboratory and experimental investigations, mathematical and physical simulation as well as the theoretic analysis and their summarizing based on the standard methodologies have been provided. The stable form of destruction of the development and breakage headings has been defined and change dependency of deformation depth of the development and breakage headings containing massif has been identified
Rational use and protection of subsurface resources in the underground mining of ore deposits in conditions of technogenesis
The basic scientific and practical results of rational use and protection of subsoil under underground mining of ore deposits in the conditions of technogenesis are based on reliable geological and surveying and geomechanical support, taking into account the stability of rock masses and the dimensions of the contour energy zone. It is recommended to build ore contours based on the data of advanced exploration (drilling of explorers through 25 m, test wells – after 5-6 m and explosive wells – through 1,2-1,5 m)
Enhancement of confined blasting of ore
Underground mining of ore deposits features worsening of geological and geotechnical conditions, exclusive standards of environmental protection and subsoil conservation as well as more stringent requirements of life safety in the influence zones of mining. This study focuses on higher efficiency of confined blasting through justification of blast design with regard to a required grain-size composition of broken ore (average linear size of ore particle after confined blasting) and safety of guarded objects in terms of industrial and residential infrastructure in the influence zone of mining (the Ingul River underflow, domestic buildings and social framework objects in the settlement of Kizelgur in the suburb of the Kropyvnytskyi city, Ukraine, etc.). The study used analytical, mathematical, in-mine, laboratory and experimental research methods, mathematical and physical modeling, as well as the analysis and assessment of the confined blasting technologies, implementation analysis of pilot confined blasting at the preset grain-size composition, and the analysis of geological and geomechanical conditions on Level 280–210 m in the Michurin deposit (Ukraine) by standard and new procedures (developed with participation of the present article authors). The novelty of this study is justification of the ratio of fragmentation by confined blasting as 1.2–1.3. The fragmentation ratio is one of the main parameters in calculation of length of a section composed of layers (rows). After confined blasting in such section, fragmentation is limiting and equals on average 3.0 kg/m3 at rock hardness of 12–18 and more on Protodyakonov’s scale. As a result of the implemented research, a seismically safe confined blasting technology was developed to be applied in extraction of ore bodies 1, 4, 5 and 10, as well as residual reserves on level 280–210 m of the Michurin deposit. The ecological and social efficiency of the engineering solutions is evaluated
Increase of ores mining safety based on combined backfilling of mining chambers space
Main research and practical results presented devoted to increase of ores mining safety, based on combined backfilling of mining space. An actuality of the solid stowing usage for backfilling of stoped excavation space shown, when combined with loose stowing during underground mining of deposits.
A methodology of research and peculiarities of mining blocks chambers isolation presented when using loose mixture in the combined stowing
Paramagnetic Meissner effect in ZrB12 single crystal with non-monotonic vortex-vortex interactions
The magnetic response related to paramagnetic Meissner effect (PME) is
studied in a high quality single crystal ZrB12 with non-monotonic vortex-vortex
interactions. We observe the expulsion and penetration of magnetic flux in the
form of vortex clusters with increasing temperature. A vortex phase diagram is
constructed which shows that the PME can be explained by considering the
interplay among the flux compression, the different temperature dependencies of
the vortex-vortex and the vortex-pin interactions, and thermal fluctuations.
Such a scenario is in good agreement with the results of the magnetic
relaxation measurements.Comment: accepted by New Journal of Physic
ТЕХНОЛОГІЯ ОСВІТЛЕННЯ ТУНЕЛІВ
The development of high quality and energy efficient lighting tunnel to ensure the necessary level of safety and visual comfort of the appropriate term design is a complex technical problem, whose solution is necessary to use modern methods of design based on existing regulations specific to these systems. An analysis of the factors affecting the visual process of the driver in the process of moving through the tunnel and development of real tunnel lighting system based on the proposed lighting technology design of such facilities have been fulfilled. The design of the tunnel lighting system was carried out taking into account zoning. To solve the problems of adaptation in the entrance area of the tunnel in the daytime, high illuminace of the road surface is ensured by installing a significant number of lighting devices. The recommendations on the characteristics of road surface and lighting devices lighting system to ensure the requirements of existing standards of comfort and light environment are presented.Рассмотрены особенности и нормы освещения тоннелей для обеспечения безопасности и зрительного комфорта с учетом адаптационных процессов. Продемонстрирована возможность использования компьютерного моделирования освещения для создания качественной осветительной установки тоннеля с учетом зонирования. Приведены результаты проектирования системы освещения тоннеля в Австралии.Розглянуто особливості та норми освітлення тунелів для забезпечення безпеки і зорового комфорту з урахуванням адаптаційних процесів. Продемонстровано можливість використання комп'ютерного моделювання освітлення для створення якісної освітлювальної установки тунелю з урахуванням зонування. Наведено результати проектування системи освітлення тунелю в Австралії
Research of technologies and technical means for drilling and blasting of horizontal mine workings
The main scientific and practical results of the study of technologies and technical means for drilling and blasting horizontal and inclined (up to 120) mine workings based on high-performance self-propelled drilling, loading and delivery and auxiliary equipment taking into account the study of changing geomechanical, mining and hydro-geological conditions of the field are presented and new designs of prismatic cuts. A technological audit of drilling and blasting of horizontal openings and calculation of the parameters of drilling and blasting of prismatic cuts was performed, which is provided by self-propelled drilling machines, for example, Russian, Ukrainian and Belarusian manufacturers, as well as Atlas Copco, Sandvik, Tamrock and others. The research results can be used in underground mining of ore deposits of complex structure
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