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Geotechnical Risks in Underground Coal Mines  [PDF]
K. Shahriar,E. Bakhtavar
Journal of Applied Sciences , 2009,
Abstract: In this study, a quantitative approach and decision tree were employed in order to assess and manage roof fall risks as only major problem bring about geotechnical issues in Iranian coal mines. For the objectives, risk was assessed due to the determination of likelihoods and cost of consequences (outcomes) by the analysis of assembled roof fall data from 5 different coal regions comprising several underground coal mines in Iran. In addition, the cost of consequences is considered by a relative cost. Then, it was concluded that the annual average accidents in the all investigated mines are high and it is economically admissible to serve the proposed solutions for reducing the accidents.
Economic aspect of underground coal mines damping in Ostrava-Karvina basin
Dvo?á?ek Jaroslav
Acta Montanistica Slovaca , 1999,
Abstract: The contribution deals with the underground coal mines damping from the economic point of view. It mentions the basic groups of cost items connected with the mine damping process and their sources. The most important is the subsidy from the state budget. The autor presents his opinion concerning the decreasing economic requirements in the underground coal mines damping process.
The problem of liquidating the buildings of former underground brown coal mines in the Podkru noho í area in connection with the decree of the czech bureau of mines no. 52/1997, collection of laws, and problems of open cast mines in places of their occurrences
Kryl Václav,Hudeèek Vlastimil,Fr?hlich Emil
Acta Montanistica Slovaca , 2000,
Abstract: The contribution deals with the problems of liquidating buildings of former underground mining, especially of shafts of closed and damped mines. It is stated that strict maintaining the Decree of the Czech Bureau of Mines (èBú) No. 52/1997, Collection of Laws, has its justification for deep and gassy hard coal mines, but it cannot be absolutely valid in the full extent for shallow ore, and mainly brown coal mines. An example of the analysis of shaft depths of the Sokolov District and the liquidation of some shafts of the Most Coal Company, joint-stock company in Most is adduced. Moreover, the liquidation of objects of development and preparatory workings of former underground mines using the open-cast mining method and related problems are discussed in the contribution.
Utilization of Thermal Energy of Mine Waters from Flooded Underground Mines
Bed?ich Michálek,Daniel Holéczy,Petr Jelínek,Arno?t Grmela
Acta Montanistica Slovaca , 2007,
Abstract: Dozens of ore, uranium and coal underground mines have been closed in the Czech Republic recently as a result of ending or considerable cutting down the mining of raw materials. After the completion of all necessary works associated with the decommissioning of underground mine workings, the mines were mostly left to spontaneous natural flooding with water. The volumes of mine waters in the underground reach up to millions of cubic metres. Taking into account the huge volumes and temperature of waters, which is in range of 10 to 290C at the site of draining from the underground, mine waters represent a considerable and stable source of thermal energy, the utilization of which is still wholly neglected. The authors inform about the principles of the use of mine waters for this purpose and about two projects that are in a different stage of realization.
Vlastimil Hude?ek,Petr Urban,Pavel Zapletal
Rudarsko-Geolo?ko-Naftni Zbornik , 2011,
Abstract: In the article, degasification methods to drain the gas from the underground parts of coal mines in the Czech Republic are described. The authors are concerned with the possibilities of and new trends in ensuring safety by means of drilling operations. Examples of applications of degasification in mine plants in the Czech Republic, above all in a hard coal deposit in the Ostrava-Karviná Coalfield in the Upper Silesian Basin are presented.
To the problem of coal mines damping in Ostrava - Karvina basin  [PDF]
Dvo?á?ek Jaroslav
Acta Montanistica Slovaca , 1998,
Abstract: The damping of inefficient mines caused the closure of 4 underground coal mines in the Ostrava-Karviná basin. A time span between the beginning of damping and mining activity finishing can be very short or, on the other hand, relatively long. There are positive and negative consequences in economic and social field in both cases. The contribution analyses the way of damping of these closed underground coal mines on the basis of statistical information.
Rock Load Estimation in Development Galleries and Junctions for Underground Coal Mines: A CMRI-ISM Rock Mass Rating Approach  [PDF]
Avinash Paul,V. M. S. R. Murthy,Ajoy Kumar Singh
Journal of Mining , 2014, DOI: 10.1155/2014/618719
Abstract: Rock mass rating (RMR) plays important role in design and selection of support system (Ghosh, 2000). For stability assessment of rock mass it is very important to know the amount of rock load mobilized around the development gallery which is estimated using RMR (Singh et al., 2003, Barton et al., 1974, Bieniawski, 1984, and Ghosh et al., 1992). In Indian coal mines, Central Mining Research Institute-Indian School of Mines rock mass rating (herein after referred to as CMRI-ISM RMR) is mostly used for formulating design guidelines for supports. In this paper an attempt has been made to correlate CMRI-ISM RMR values and rock load of galleries and junctions for different gallery widths, ranging from 3.6?m to 4.8?m, at different densities of roof rocks. The proposed empirical expression can help in quick design of support system for underground coal mines working in the same regime. 1. Introduction Roof and side falls in underground coal mines constitute the major reason for underground accidents and fatalities even today. Statistical analysis reveals that the share of roof and side falls contributes to 28.5% of the fatalities [1, 2]. After the development of CMRI-ISM RMR, an empirical approach for rock load estimation and support design in Indian underground mine roadways, the support related accidents have started declining though they still haunt the mining engineers every now and then. The RMR reflects the quality of roof in numeric terms and quantitative terms. It is based on five parameters and obtained after summation of all those five values. The obtained RMR is adjusted for different working conditions and then used to estimate the rock load mobilized around the galleries and junctions for design of support system for underground coal mines. 2. Study Area of Research Work The case studies incorporated in this paper are taken from different mines of Bharat Coking Coal Limited and Tata Steel Limited situated in Jharia coalfield (Figure 1) [3]. Jharia coalfield, located in Dhanbad district of Jharkhand state, is one of the largest coalfields in India that has been actively associated with coal mining activities for more than a century. The study area lies in the heart of Damodar valley along the north of Damodar river. The coalfield is named after the chief mining centre, Jharia, situated in the eastern part of the coalfield. The coal basin extends for about 38?km in the east-west direction and a maximum of 18?km in the north-south direction covering an area of about 450?km2. Figure 1: Location of Jharia coalfield in India. 2.1. CMRI-ISM RMR—An
Application of computer technologies in research of shifting soil mass to different underground mines / Применение компьютерных технологий при исследовании перемещений грунтового массива в окрестности различных подземных выработок  [cached]
Tsvetkov V. K. / Цветков Владимир Константинович,Skorokhodova A. D. / Скороходова Алевтина Дмитриевна
Internet-Vestnik VolgGASU , 2006,
Abstract: By means of the program for shifting calculation, computing and graphical aids of mathematical package MathCAD the comparative analysis of vertical components of shifting around underground mines of different cross sections was held. Mines of rectangular - parabolic cross section and rectangular cross sections were considered as examples. / С использованием программы для вычисления перемещений, вычислительных и графи-ческих средств математического пакета Mathcad проведен сравнительный анализ вертикальных составляющих перемещений вокруг подземных выработок различных поперечных сечений. В качестве примера рассмотрены выработки прямоугольно-параболического и прямоугольного сечений.
Properties of the fly ash from the Power Plant Dětmarovice from the point of view of their deposition in underground mines  [PDF]
Dirner Vojtech,Raclavská Helena
Acta Montanistica Slovaca , 2001,
Abstract: Mining for the Purposes of Disposal Facilities, Requirements and Conceptions. Mining for the purposes of disposal can be instrumental in environmental protection in the future. Therefore the utilization of residues in the mining process has to be put into the foreground, whether they are a product of the mining activity itself or coming from other sources. It is possible to use the residual products as filling or building materials. Within the constantly increasing demand for building materials in the mines it is possible to combine the advantages that improve mine safety, rock mechanics and support with the secure long-term sealing of mineralized industrial residues in the lithosphere. Also the disposal of polluted, water-soluble and toxic or radioactive waste in a suitable geological formation underground can be realized ensuring long-term safety. This long-term safety is guaranteed by a multiple system of geological and technical barriers. The storage can b conducted in appropriate void space like chambers, caverns, drifts or boreholes with or without the opinion of retarding the material.Contribution is discussing the possibility of the deposition on fly ash produced by thermal power plants which are using low-grade brown coal as a fuel. Properties of fly ash were studied id detail on samples from Power Plant Dìtmarovice, northern Moravia.Results proved that fly ash can be deposited safely in underground.
Numerical modelling of the effect of weathering on the progressive failure of underground limestone mines  [PDF]
Siavash Ghabezloo,Ahmad Pouya
Physics , 2008,
Abstract: The observations show that the collapse of underground limestone mines results from a progressive failure due to gradual weathering of the rockmass. The following stages can be considered for the limestone weathering and degradation process in underground mines: condensation of the water on the roof of the gallery, infiltration of water in the porous rock, migration of the air CO2 molecules in the rock pore water by convection and molecular diffusion, dissolution of limestone by CO2 rich water and consequently, reduction of the strength properties of rock. Considering this process, a set of equations governing different hydrochemo-mechanical aspects of the weathering phenomenon and progressive failure occurring in these mines is presented. Then the feasibility of numerical modelling of this process is studied and a simple example of application is presented.
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