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Calculation of the mining support in tunnels and/or underground facilities can be based on application of contemporary numerical methods, but sometimes it can be performed with the classical methods too. These methods can be found to be used in order to choose variants and ways of supporting, but also in the moments that unpredictably appears during the construction of facility. Before installing a permanent mining support, these methods can help the projector at the selection of type of support and ways of tempor...

The Makmal gold deposit is located in the Republic of Kyrgyzstan. As a result of mining operations, under the bottom of the quarry, an open worked out space was formed with access to the surface above each chamber and overhanging rock consoles. This mining situation at the field caused the danger of sudden collapses of rock consoles and the walls of the chambers of the separating pillar. In this article, in order to justify the method of filling the voids and choosing the technology for the extraction of the pilla...

This article presents an analysis of the stability of stopes that is based on the mathematical modelling of stress-strain states and the criterial assessment of destruction of the heterogeneous layered rock mass encompassing a system of mine openings. The problem solution has been carried out in the plane strain state setting. The state of an undermined stratum has been described by an ideal elastic-plastic medium. The technological interbed and the roof of an upper bed have been modeled by a layered medium includ...

This article considers the methodical provisions of geomechanical analysis of a change in the stress-strain state of the undermined saliferous mass over time. The mathematical modeling of deformation and destruction of the water-blocking strata (WBS) has been carried out in the elastic-plastic setting for plane-strain conditions (PS). The safe conditions of undermining of the water-blocking strata (WBS) have been assessed and the geomechanical justification of used additional protective measures has been made in t...

Systematization of ore deposits is carried out according to geomechanical conditions on the basis of tectonic features. In total, more than 120 underground mines have been analyzed. Four models of the geo-environment are distinguished. They make it possible to differentially describe the nature of the change in the stress state with increasing depth. The efficiency and reliability of the use of typical geomechanical conditions of rock massifs for determining the field of application of geotechnologies is shown. Co...

The results of the study of high-Mg rocks from the Aganozero chromite deposit, located in the Republic of Karelia, are reported. It is a complex type of deposits. Other promising useful minerals, in addition to chromite ore mining, are Mg-rich ultramafics such as olivinite, dunite, serpentinite and pyroxenite. High-Mg dunite units are thick, and their MgO concentration varies 36.97 from 46.77%. Aganozero dunite is a good raw material for the production of refractory materials, e.g. refractory bricks, steel furnace...

The paper gives comparative analysis of the method of vacuum extraction of Chaga carried out by the authors. The process supposed that the ground Chaga was pre-vacuumed for 10 minutes in order to release the holes from air and moisture vapor and conduce efficient time pregnation of the extractant; further, the author saddled still dewatering the ratio 1:10 and kept at the temperature of 70В°C.In the process of extraction, the pressure was hourly lowered to 0.3 atm, which promoted the boiling of the extractant in a...

The former village Rosiuta, now neighborhood of Motru city, located in Motru mining basin, is surrounded by sterile waste dumps and lignite storage platforms. These are a constant source of particulate matter which is carried by the wind over the inhabited area and affects the quality of breathing air. In order to evaluate the powders dispersion from these sources, it was made chemical and granulometric analysis of the particulate matter on several material samples collected from the area. Based on various meteoro...

The methane hazard is one of the main natural hazards occurring in underground hard coal mining. This hazard is related to the potential ignition and/or explosion of methane when mixed with air. The underlying cause of this problem is methane release from the body of coal, the goaves with caving and the excavated coal area. The region most vulnerable to this hazard in coal exploitation during longwall ventilation using the U-type system from the exploitation field borders is the intersection of the longwall and th...

This paper discusses the causes of surface deformation as a consequence of mining activities. Surface deformation associated with underground coal mining, named subsidence, is a gradual settling of the earth?s surface. Subsidence effects can result from all mining methods, but especially coal mining. Some of the primary effects of surface subsidence include damages of infrastructure (buildings and roads). The most vulnerable areas for deformation are those where underground mine working are closed to the ground su...

Industrial ventilation and air conditioning systems aim at ensuring the air purity and microclimate conditions of the human activity and the nature of the technological process. These ventilation systems help in maintaining work capacity, removing occupational illnesses, increasing the labour productivity and the quality of work-related products. The structure of ventilation systems in spaces and industrial premises requires a thorough knowledge of the technological processes that take place, of the equipment and ...

The deviation from the design shape of an underground structure cross-section and its influence on the structure stress state are under consideration. External loads, corrosion and peculiarities of construction techniques, are assumed as the most probable causes of the deviation. The influence of shape changing is estimated by the analytical design method for multilayer underground structures with layers of variable thickness. The method is based on a rigorous analytical solution of the corresponding plane problem...

The use of the borehole camera when observing the blasting results in clay soils provides accurate data on the effects. For this purpose, GNSS, Heavy Duty GeoVision borehole camera, and laser (EDS-C) integration were used. The spherical cavity formed after the detonation of the explosive charge in the bottom of the borehole was measured with the aid of a borehole camera and a laser system. The measurement data obtained was used to determine the coordinates of the boreholes at a certain depth of recording based on ...

The geological environment is essentially heterogeneous, consists of blocks, layers, lenses, joints of various shapes and sizes, lying horizontally, obliquely or in the form of complex folds in the earth's crust, and it is characterized by great complexity and heterogeneity. The shear in the direction of the joint is one of the main reasons for the destruction of the underground tunnels and mine workings, wellbores. Understanding of shear behavior allows optimal design of mining facilities and prediction of the ge...

The accelerated ageing affects the quality of an important element of the belt conveyance ? a conveyor belt. This paper analyses the resistance of the belt cover layers to the deterioration caused particularly by the accelerated ageing. The investigation was carried out using the fabric conveyor belts of the P 2000/4 type (4-layer textile belts with a polyamide carcass, the strength of 2,000 N/mm) at different ageing periods. The effect of ageing on the rubber cover layers was identified on the basis of the observ...

The conveyor belt as the composite is made of different materials to ensure its required mechanical properties that correspond to the handling characteristics of the transported material. The basic elements of the composite structures are top and bottom cover layer from rubber and carcass with fabric plies. The composite structure - the number and type of fabric plies, the type and thickness of cover layers or the bumpers is designed according to the specific mining conditions. The bumper is designed to absorb the...

In Poland, in the Upper Silesian Coal Basin, underground exploitation of coal seams has been conducted for numerous years, causing a gradual depletion of deposits from previously mined levels. Hence, the depth of mining works carried out each year increases by 5 ? 8 m on average. Currently, already several mines operate at the level of 1,000 m and greater. Designing ground support of excavation and maintaining its functionality at such significant depths has, therefore, become a very important issue from a practic...

After 1989, when significant economic and social changes took place in the Czech Republic, the mining of most minerals was gradually reduced by 30-40%. The development of the external environment, especially the external conditions directly/indirectly - positively/negatively affects mining of mineral resources. In the presented article, we examine the dependence between exploitation of black coal and external conditions in terms of management. Selected macroeconomic indicators (not only in the Czech Republic but a...

The investigated lead - zinc ore panel is located in the Blaznei Valley ore deposit, Romania. Applying traditional methods for determining the average thickness proves useful in its exploration, although there are only four points of thickness measurement, located in each corner of the exploration panel. Later, in the second stage of the exploitation process (preparation), when the exploration panel becomes an operating (exploitation) panel by contour mining of four workings, two groves on direction and two runs, ...

The quantification of the influence exerted on the targets from an establishments concerned by the SEVESO II Directive requirements can be performed through the potential danger resulting by the aggregation of the gravity index and the propagation flow index. Starting from the environment?s specific characteristics, the major accident?s propagation kinetics and the distance between the target and the danger source, the paper has as goal to depict a propagation flow determination method. In this index determination...

With regard to the ever-increasing road traffic density, the demands on the transport infrastructure are also increasing, or more precisely on its quality. For this reason, even a slightly damaged road surface is often considered unsatisfactory and its reconstruction is necessary. Increasing the amount of heavy and especially overloaded vehicles has a significant impact on the life of the roads, as they cause permanent deformation of the surface layers of the road. A further significant influence is represented by...

At present, we have a number of legal provisions in the Czech Republic that give miners the responsibility to make economic use of mineral deposits. The main one is Upper low No. 44/1988 Sb. on the Protection and Use of Mineral Resources, referred to as the Upper Law, there are also laws, decrees and government orders that are closely related to or follow the Upper Act or impose further expansion obligations for the economical exploitation of mineral resources in our country. Despite a number of existing legal pro...

The Lojane deposit is a characteristic epithermal As-Sb type of mineralization located in the contact boundary between the Tertiary volcanites and the Jurassic ultrabasites in the immediate vicinity of the village of Lojane in the northern parts of the Republic of Macedonia. Mineralization is of a vein type, and the main bearers of As-Sb mineralization are the stibnite (antimonite) and the realgar, followed at the places by the orpiment. Four morphological types of mineralization are defined by the latest macro-sc...

Assessment of raw materials projects concerns a special, narrow area. Their economic result depends on internal and external variables. Much more objective and probable results of the assessment are obtained by extending the analysis of the project with the investor's and environment's perspective. This paper examines the possibilities of project implementation in financial and competency frames from the investor?s perspective. From the perspective of the environment, the positioning of the project in the sector a...

Antropogenic seismicity is one of the most important geomechanical hazard encountered in Polish deep copper mines. Obviously, it may have a negative impact on the people?s safety and the production process. In such circumstances, a number of both active and passive prevention measures have been implemented in the mines, at least partially. One of the most effective, applied for many years, active means used for seismic hazard reduction, is multi-faces blasting works which by assumption should result in release of ...

The paper presents the results of theoretical and practical research on developing the infrastructure for assessment of overall risk (explosion / occupational terrorist attack) associated with unwanted events such as major accidents that can occur at explosive storehouses for civilian use. The scientific research outlined in this article was carried out within the NUCLEU Project PN 16 43 02 15 - ?Research on increasing safety levels at technical facilities for storage of explosives for civil use?. The key element ...

Adsorption of CO2 and N2 onto coal is used to describe its porous structure. It is mainly CO2 that allows for the analysis of the adsorption on coal, whose porous structure is dominated by micropores. Depending on the specificity of the transition process of CO2 molecules from the free state to the adsorbed state, the thermal characteristics of the adsorption process varies as well. The article presents the test results of three types of coal from Polish mines. The researcher carried out volumetric analyses of gas...

The planned maintenance activities of the mining technological equipment are carried out on the principles of risk management and is done in order to prolong their duration of operation and to reduce the production cost. The quick possibilities of reducing production losses due to accidental stoppages of quarries and underground exploitation equipment, depend on the establishment and application of reconditioning methods of the subassemblies and spare parts that are frequently defects and replacement. The rotary a...

The target of this article is the providing of the brief information about preventing the dust spreading problems solving during operations of machinery equipment in brown coal open pit mines and in coal dumps. The main part of this paper briefly describes operation tests of the new rotary mist unit realized during last years. The increased concentration of the dust in the air causes important health hazard. The dust is very bother factor. The occurrence of the dust in operation area is the source of danger fire r...

The particularities of the hydraulic system of the roof supports are determined by the repetitive structure specific to the supporting component, by the supply network, by the operating liquid and by the length of the coalface, as well as by the operation principle of the pumping station supplying the execution elements with the average flow given by the load and the resistance of the hydraulic networks. The paper highlights all these particularities bringing forward a series of practical details for calculation o...

One of the main problems industries in general are facing is the prediction of errors or failures of the most sensitive or critical assets of their equipment. For this reason, techniques based on predictive maintenance are emerging, searching for the early detection of possible cracks, imperfections or defects that are likely to cause an accident or the partial or complete shutdown of a plant. The main objective is to anticipate breakages in order to improve the planning and scheduling of control and maintenance o...

The paper presents a patented and copyright protected concept of constructing a shaft lining that goes through salt rock massif having strong rheological properties and being susceptible to leaching. In the case of salt layers, especially on significant depths (over 1000 m) the relative convergence of the heading contour may amount even to 0,18 m/year. That results in the fact that any other method of securing the shaft lining, e.g. by making it flexible, will not be sufficient to ensure the stability of the shaft...

Various methods are used in the mining of minerals, where the transport of material is an integral part. This paper deals with the transport problem of backfill material from surface stock to underground tank. To solve the problem is applied the capacitive calculation of transport using 2 trucks and a loader. The calculation is complemented by graphic models. The backfill material is available on 5 surface stocks. It is possible to transport the material directly to the workplace from each heap, which is not effec...

The article presents the second part of the results of asymmetrical disc tools laboratory tests. The first part of this study was presented at SGEM International Conference in 2017. Asymmetrical disc mining tools can be used for mechanical mining of hard rocks, as an alternative to blasting methods. The study was conducted on a dedicated laboratory stand, with an installed drive power of 80 kW. Stand consists of rotating rock sample, mined by special plate equipped with asymmetrical disc tools by a so-called under...

Natural sources can contribute with significant radiation quantities toward the total radiation exposure that humans receive. The majority of this natural radiation is harmless to humans in the ambient environment. However, radon, a large component of the natural radiation which humans are exposed to, can pose a threat to the workers health when radon gas accumulates in poorly ventilated occupational settings. Radon is the most hazardous natural source of radiation. Even if it is an inert gas, having no color, tas...

This article is intended to bring closer the raw materials policy of the Czech Republic, which is part of the European Union, so the article also refers to marginal and raw material policy of the European Union and secondly it is the aim of article introducing potential sources of mineral resources in our territory. Raw material policy can be understood as a political, legislative and administrative framework for reliable, affordable and long-term sustainable supply of raw materials. Raw material policy is a strat...

The rocks exploited in quarries have certain physical, mechanical and technological characteristics that favors the intense wear, especially by abrasion of the active surfaces of the subassemblies of the technological equipment. Some spare parts and subassemblies are subject to similar wear phenomena, as is the case with the excavators bucket teeth in the lignite pits and the loaders cup teeth in the basalt pits. In the case of the basalt aggregates which are the main raw material needed for the development of the...

The companies need to change in order to be competitive on the current market. There are multiple ways to change in order to face the market. One of the most efficient instruments is organization development which refers to increasing the individual, group and organization performances, to improving the organization ability to respond efficiently to outside changes. The organization development refers to increasing the internal capabilities, ensuring that the organization structures, human resource systems, posts,...

The paper deals with the negative effects of mining on the transport network in the Moravian-Silesian area, especially is focused on problems reflected in construction layers of transport-related structures (railways, roads, area storage and handling areas). With the extraction downturn, the sources and objectives of transport have changed including the characteristics of transport flows of all traffic roads and connections. Various measures for all transport modes situated in Moravian-Silesian region are identifi...

The target of this article is the presentation of the first steps of solving the project No. TH03020368 from the programme EPSILON titled ?The optimisation of the shape and material of ground and mining machines research?. The main topic of this article is the optimization of the tooth shape and primarily the optimization of the materials used for manufacturing of cutting bodies of the ground and mining machines. This research is necessary for increasing of efficiency of mining process in conditions of the Most Ba...

Under intense stress, energy consumption undergoes essential changes that largely depend on functional characteristics of the respiratory system, which in turn are in close correlation with the body?s training degree and physical demand. During a pronounced dynamic effort, there is a progressive decrease in blood oxygen saturation and an increase of pulse. Cardiac rhythm is a physiological parameter commonly used in telemonitoring as it allows the assessment of rescuer?s general condition, heart rhythm disorders b...

In the combustion processes the nature and concentration of the developed gaseous effluents depends on the type of materials that are subject to combustion as well as on the conditions in which the oxidation processes take place. The purpose of this paper is the experimental determination of the combustion parameters and the study of the developed gaseous effluents from several combustible materials. The production of gaseous products resulting from combustion results in different yields depending on several param...

Production and consumption of electricity is, in contemporary society, the significant technical indices and social level you have reached. The use of electricity involves electric power systems (ESS), representing the large technical systems, which shall incorporate the Assembly plants for the production, transportation, distribution and consumption of electricity. Within the framework of the ESS are retrieved hydroelectric power plants (CHE), which represents about 25 percent of the installed power in power stat...

The decisive factor in the process of under pressure networks inspection is determined by the correct choice of the control method in order to observe with great attention the possible faults caused by the physical wear and tear resulting from the long use. Emphasis is placed on safety conditions of under pressure equipment, which include mandatory minimum technical requirements for periodic checking of under pressure networks for pressurized, liquefied or dissolved gas. Defectoscopy is a set of procedures used to...

Methane gas, one of the underground mine atmosphere, is the main hazard for the workers in this field. The risk of occurrence of an explosive atmosphere and the consequences are different from one mine to another, based on the mine type, its configuration, the extracted coal and the probability of the methane and coal dust occurrence. With every prevention measure taken, the potential risk of an explosion cannot be excluded from the firedamp mines, just reduced as much as possible. The controlled researches regard...

Protecting human labors process seeks to eliminate and/or reduce the potential causes of injury and disease in order to achieve full control of risks from hazards associated. With all the technical progress and technology in most industries, and especially in the oil and natural gas, there are failures with casualty and property damage. For this reason, it is indispensable the presence of the special intervention and rescue teams to limit/ liquidation, failure that generates explosive atmosphere and/or toxic and r...

A wireless system of continuous monitoring of pressure in a leg mounted in a powered roof support was designed in order to ensure the continuity of longwall coal mining process. Wireless multi-channel signal transmission in the longwall was applied for the first time. The extension of the power cell enabled maintenance-free use of the system and ensured comprehensive control of the support. The presented system monitors the pressure value in the spaces under the leg?s piston mounted in a powered roof support as we...

Fuel and energy management and related energy security are key issues for every country. The selection of energy sources used by individual countries depends on the possessed resources of energy raw materials, the economic position and, to an increasing extent, the approach to environmental protection. These factors shape the so-called energy policy of a given country. In the case of Poland, this policy is based on conventional energy sources. The main energy resource of the country is hard coal, the extraction of...

One of the major problems associated with exploitation of the copper ore deposit in underground mines in Poland is the local disturbance in a state of stable equilibrium manifested in a sudden release of strain energy stored in the deformed rock mass. It occurs mainly in the form of dynamic events which may result in rockbursts and roof falls. In order to face this threats, a number of organisational and technical prevention methods are applied in mines. It should be also noted that the greatest difficulties with ...

The subject of this paper is the assessment of the influence of the construction and design elements on traffic safety at level crossings in undermined areas. The first part is dedicated to level crossings in the Czech Republic and accident rates at level crossings in the Moravian-Silesian Region. The following part describes the in situ experiment, which was conducted at selected crossings with different types of safety arrangements, intensity of traffic and traffic moments. Our results were compared with the res...