Pub Date : 2022-09-30DOI: 10.33271/mining16.03.054
H. Symanovych, I. Salieiev, M. Shyshov, M. Odnovol
Purpose. Determination of the rational interaction modes between the fastening system and the extraction working enclosing mass in the zone of stope operations influence. Methods. An algorithm for searching for optimal solutions for the interaction modes between the fastening system and the coal-bearing mass has been substantiated. The deformation-strength characteristics of the fastening system elements have been agreed. The design parameters of the support elements have been optimized according to the criterion of their equal strength. According to the optimal parameters, a methodology for calculating the function that describes the rational deformation-strength characteristic of the fastening system, depending on the mining-geological conditions, has been developed and substantiated. Findings. Computational experiments have been conducted to determine the rock mass deformation-strength characteristic. Based on the normative documents, the sizes of the natural equilibrium arch have been calculated. The adequacy of methodical principles for minimizing the load on the fastening system has been proved. The patterns for the influence of geomechanical factors on the choice of optimal parameters of the fastening system deformation-strength characteristics have been determined. A methodology for calculating the rational parameters of the fastening system and its constituent elements has been obtained. Originality. Combined studies of minimizing the load on the fastening system have been conducted. The patterns for the influence of geomechanical factors on the choice of load-bearing capacity and the yielding property value of the fastening system have been determined. Regression equations have been obtained for calculating the fastening system optimal parameters with a geomechanical index of working conditions. This enables implementation of a unified strategy for resource-saving improvement in fastening systems. Practical implications. A methodology has been developed for obtaining the weakening mass deformation-strength characteristic, depending on the depth of mine working location, the texture of the rocks in the coal-overlaying formation and its strength properties. The applicability of the methodology for the implementation of a unified strategy of resource-saving improvement of the mine working fastening systems for the Western Donbas mines has been proved.
{"title":"Substantiating the optimization solutions for the mine working fastening system interaction with the enclosing rock mass","authors":"H. Symanovych, I. Salieiev, M. Shyshov, M. Odnovol","doi":"10.33271/mining16.03.054","DOIUrl":"https://doi.org/10.33271/mining16.03.054","url":null,"abstract":"Purpose. Determination of the rational interaction modes between the fastening system and the extraction working enclosing mass in the zone of stope operations influence. Methods. An algorithm for searching for optimal solutions for the interaction modes between the fastening system and the coal-bearing mass has been substantiated. The deformation-strength characteristics of the fastening system elements have been agreed. The design parameters of the support elements have been optimized according to the criterion of their equal strength. According to the optimal parameters, a methodology for calculating the function that describes the rational deformation-strength characteristic of the fastening system, depending on the mining-geological conditions, has been developed and substantiated. Findings. Computational experiments have been conducted to determine the rock mass deformation-strength characteristic. Based on the normative documents, the sizes of the natural equilibrium arch have been calculated. The adequacy of methodical principles for minimizing the load on the fastening system has been proved. The patterns for the influence of geomechanical factors on the choice of optimal parameters of the fastening system deformation-strength characteristics have been determined. A methodology for calculating the rational parameters of the fastening system and its constituent elements has been obtained. Originality. Combined studies of minimizing the load on the fastening system have been conducted. The patterns for the influence of geomechanical factors on the choice of load-bearing capacity and the yielding property value of the fastening system have been determined. Regression equations have been obtained for calculating the fastening system optimal parameters with a geomechanical index of working conditions. This enables implementation of a unified strategy for resource-saving improvement in fastening systems. Practical implications. A methodology has been developed for obtaining the weakening mass deformation-strength characteristic, depending on the depth of mine working location, the texture of the rocks in the coal-overlaying formation and its strength properties. The applicability of the methodology for the implementation of a unified strategy of resource-saving improvement of the mine working fastening systems for the Western Donbas mines has been proved.","PeriodicalId":43896,"journal":{"name":"Mining of Mineral Deposits","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2022-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46891139","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-30DOI: 10.33271/mining16.03.031
Yurii Vynnykov, M. Kharchenko, S. Manhura, H. Muhlis, A. Aniskin, A. Manhura
Purpose is to perform analysis of corrosion durability (fatigue) of pump rod materials in terms of various chemically active simulation environments, and study influence of economically modified rare-earth impurity on corrosion fatigue strength of pump rod materials. Methods. 40 and 20N2M steel grades have been applied as well as experimental steel (ES). Steel of the conditinal ES grade has been melted within a pilot site of Institute of Electric Welding Named after E.O. Paton of the National Academy of Sciences of Ukraine. The steel was alloyed economically by means of a micro impurity of a rare-earth element (REE) being 0.03% of cerium; in addition, it contained comparatively low concentration of sulfur and phosphorus as well as minor concentration of dissolved hydrogen. The following has been used as simulation environments: 1) NACE environment (i.e. 5% NaCl solution which contained 0.5% СН3СООН, and saturated H2S; t = 22 ± 2°C; pH = 3.8-4.0); 2) 3% NaCl solution without hydrogen sulphide. Once every day, the environment was replaced to oxygenate it up to 8-10 mg/l concentration. Findings. Stability against sulfide stress-corrosion cracking (SSCC), hydrogen initiated cracking (HIC), and corrosion fatigue of steel of deep pump rods for oil industry has been studied. It has been defined that the experimental steel, modified economically by means of micro impurities of a REE, meets NACE MR0175-96 standard in terms of chemical composition as well as strength; in turn, 20N2M and 40 steel grades have high resistance neither to SSCC (threshold stresses are < 0.8 s) nor to corrosion fatigue attack; moreover, steel grade 40 has demonstrated low resistance to HIC (CLR > 6% and CTR > 3%). Originality. It has been identified that corrosion fatigue attack results from hydrogen penetration of steel initiating its cracking and hence destruction under the effect of alternating loads accelerated by the action of corrosive environment. Further, surface micro destructions, influenced by micro stresses, transform into large discontinuities and cracks with following macro destructions. Practical implications. It has been proved that high resistance to corrosion cracking can be achieved by means of refining of pump-rod steel of ferrite and perlite type using metallurgical methods, i.e. 0.01-0.03% REE microalloying.
{"title":"Analysis of corrosion fatigue steel strength of pump rods for oil wells","authors":"Yurii Vynnykov, M. Kharchenko, S. Manhura, H. Muhlis, A. Aniskin, A. Manhura","doi":"10.33271/mining16.03.031","DOIUrl":"https://doi.org/10.33271/mining16.03.031","url":null,"abstract":"Purpose is to perform analysis of corrosion durability (fatigue) of pump rod materials in terms of various chemically active simulation environments, and study influence of economically modified rare-earth impurity on corrosion fatigue strength of pump rod materials. Methods. 40 and 20N2M steel grades have been applied as well as experimental steel (ES). Steel of the conditinal ES grade has been melted within a pilot site of Institute of Electric Welding Named after E.O. Paton of the National Academy of Sciences of Ukraine. The steel was alloyed economically by means of a micro impurity of a rare-earth element (REE) being 0.03% of cerium; in addition, it contained comparatively low concentration of sulfur and phosphorus as well as minor concentration of dissolved hydrogen. The following has been used as simulation environments: 1) NACE environment (i.e. 5% NaCl solution which contained 0.5% СН3СООН, and saturated H2S; t = 22 ± 2°C; pH = 3.8-4.0); 2) 3% NaCl solution without hydrogen sulphide. Once every day, the environment was replaced to oxygenate it up to 8-10 mg/l concentration. Findings. Stability against sulfide stress-corrosion cracking (SSCC), hydrogen initiated cracking (HIC), and corrosion fatigue of steel of deep pump rods for oil industry has been studied. It has been defined that the experimental steel, modified economically by means of micro impurities of a REE, meets NACE MR0175-96 standard in terms of chemical composition as well as strength; in turn, 20N2M and 40 steel grades have high resistance neither to SSCC (threshold stresses are < 0.8 s) nor to corrosion fatigue attack; moreover, steel grade 40 has demonstrated low resistance to HIC (CLR > 6% and CTR > 3%). Originality. It has been identified that corrosion fatigue attack results from hydrogen penetration of steel initiating its cracking and hence destruction under the effect of alternating loads accelerated by the action of corrosive environment. Further, surface micro destructions, influenced by micro stresses, transform into large discontinuities and cracks with following macro destructions. Practical implications. It has been proved that high resistance to corrosion cracking can be achieved by means of refining of pump-rod steel of ferrite and perlite type using metallurgical methods, i.e. 0.01-0.03% REE microalloying.","PeriodicalId":43896,"journal":{"name":"Mining of Mineral Deposits","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2022-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44586239","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-30DOI: 10.33271/mining16.03.101
V. Tsopa, S. Cheberiachko, O. Yavorska, O. Deryugin, Ivan Bas
Purpose.The aim of the study is to develop recommendations for reducing the probability of accidents during the transportation of rock by dump trucks based on the analysis of the consequences of changes in the psycho-physiological states of the driver. Methods. The study used the method of “Hazard and operability studies” and the method of “Failure Mode and Effects Analysis” including the organizational, logical and mathematical, and statistical procedures aimed at obtaining the expert assessment of hazards from professional experts based on Grabs’ criteria that affect to change the psychophysiological state of the driver while driving a dump truck, their analysis and generalization of the results in order to prepare reasonable decisions. Findings. It is established that the psychophysiological state of the driver as a manifestation of fear, anxiety, doubt, uncertainty when performing discrete work, which is associated with frequent changes in the beginning of movement and stops of the vehicle (accumulation of a large number of dump trucks, complex route plan, etc.) leads to an increase in the risk of an emergency. It is determined that the highest level of emergency occurs due to emotional manifestations, that are associated with the relationship between employees, the presence of leadership support, psychological assistance, mobbing, conflict resolution and more. Recommendations have been developed to increase the level of transportation safety through the formation of an appropriate organizational culture at the enterprise, which ultimately shapes human social behaviour. Originality. The scientific novelty lies in the establishment of the values of occupational risk of an accident while driving a dump truck by the driver, which depends not only on the probability of a dangerous event and the severity of its consequences, but also on changes in the psychophysiological state of the driver, which results from the organizational culture of occupational safety at the mining enterprise. Practical implications. Consists in the development of a procedure for qualitative assessment of the risk of an accident from the psychophysiological state of the driver during the trucking of rock in the conditions of the mining enterprise. Recommendations for improving the safety of transportation through the formation of an appropriate organizational culture of the transport process are developed. An approach of taking into account the socio-psychological climate in the organization to assess the occurrence of the incident is proposed.
{"title":"Increasing the safety of the transport process by minimizing the professional risk of a dump truck driver","authors":"V. Tsopa, S. Cheberiachko, O. Yavorska, O. Deryugin, Ivan Bas","doi":"10.33271/mining16.03.101","DOIUrl":"https://doi.org/10.33271/mining16.03.101","url":null,"abstract":"Purpose.The aim of the study is to develop recommendations for reducing the probability of accidents during the transportation of rock by dump trucks based on the analysis of the consequences of changes in the psycho-physiological states of the driver. Methods. The study used the method of “Hazard and operability studies” and the method of “Failure Mode and Effects Analysis” including the organizational, logical and mathematical, and statistical procedures aimed at obtaining the expert assessment of hazards from professional experts based on Grabs’ criteria that affect to change the psychophysiological state of the driver while driving a dump truck, their analysis and generalization of the results in order to prepare reasonable decisions. Findings. It is established that the psychophysiological state of the driver as a manifestation of fear, anxiety, doubt, uncertainty when performing discrete work, which is associated with frequent changes in the beginning of movement and stops of the vehicle (accumulation of a large number of dump trucks, complex route plan, etc.) leads to an increase in the risk of an emergency. It is determined that the highest level of emergency occurs due to emotional manifestations, that are associated with the relationship between employees, the presence of leadership support, psychological assistance, mobbing, conflict resolution and more. Recommendations have been developed to increase the level of transportation safety through the formation of an appropriate organizational culture at the enterprise, which ultimately shapes human social behaviour. Originality. The scientific novelty lies in the establishment of the values of occupational risk of an accident while driving a dump truck by the driver, which depends not only on the probability of a dangerous event and the severity of its consequences, but also on changes in the psychophysiological state of the driver, which results from the organizational culture of occupational safety at the mining enterprise. Practical implications. Consists in the development of a procedure for qualitative assessment of the risk of an accident from the psychophysiological state of the driver during the trucking of rock in the conditions of the mining enterprise. Recommendations for improving the safety of transportation through the formation of an appropriate organizational culture of the transport process are developed. An approach of taking into account the socio-psychological climate in the organization to assess the occurrence of the incident is proposed.","PeriodicalId":43896,"journal":{"name":"Mining of Mineral Deposits","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2022-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42175270","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-30DOI: 10.33271/mining16.03.018
Denys Bozhyk, Mykola Sokur, V. Biletskyi
Purpose. Determining the rational operating parameters for granite crushing under impact in the field of centrifugal forces to obtain cubiform crushed stone. In order to achieve the purpose set, the task is to determine the operating parameters for obtaining the main grain-size classes: -50.0 + 20.0; -40.0 + 20.0; -20.0 + 10.0; -10.0 + 5.0 and 5.0 mm. Methods. The crushing process of granite crushed stone is studied in the conditions of the Kolomoievskyi Granite Quarry, Dnipropetrovsk region. Granite crushed stone with an initial grain-size of 100.0-0.0 mm and strength grade of M1400 is subjected to crushing. The accelerating rotor rotation frequency is the design value n = 200-1200 min-1. Fine crushing of granite is performed in a centrifugal-impact crusher by a free impact in the field of centrifugal forces. Findings. The optimal speed modes of centrifugal crusher operation, which provide the production of high-quality crushed stone with a maximum content of 90-95% cubiform fractions, have been substantiated. Originality. The yield dependences have been obtained of the grain-size classes: -50.0 + 20.0; -40.0 + 20.0; -20.0 + 10.0; -10.0 + 5.0 and 5.0 mm depending on the speed mode of the centrifugal crusher operation. Practical implications. The operating parameters for obtaining the main grain-size classes of cubiform crushed stone from granite have been determined: -50.0 + 20.0; -40.0 + 20.0; -20.0 + 10.0; -10.0 + 5.0 and 5.0 mm. In particular, it has been determined that for the production of cubiform crushed stone with -50.0 + 20.0 mm grain-size, the rotor rotation reasonable speed is 400-500 min-1 (the speed of material departure from the accelerating rotor is 45-50 m/sec); for cubiform crushed stone of -40.0 + 20.0 mm grain-size, the speed mode is 200 min-1 (25 m/sec); for cubiform crushed stone of -20.0 + 10.0 mm grain-size – 600-650 min-1 (70-80 m/sec), respectively. The maximum content of cubiform fractions in the -20.0 + 10.0 mm grain-size class is 95%, which is achieved at a rotor speed of 650-700 min-1 (departure speed is 75-80 m/sec). The maximum content of cubiform fractions in the -10.0 mm grain-size class is 94-95%, which is achieved at the accelerating rotor speed within 700-800 min-1 (departure speed is 70-80 m/sec). The obtained data make it possible to practically choose a rational speed mode of the centri-fugal-impact crusher operation to obtain the maximum yield of cubiform crushed stone.
{"title":"Determining the rational operating parameters for granite crushing to obtain cubiform crushed stone","authors":"Denys Bozhyk, Mykola Sokur, V. Biletskyi","doi":"10.33271/mining16.03.018","DOIUrl":"https://doi.org/10.33271/mining16.03.018","url":null,"abstract":"Purpose. Determining the rational operating parameters for granite crushing under impact in the field of centrifugal forces to obtain cubiform crushed stone. In order to achieve the purpose set, the task is to determine the operating parameters for obtaining the main grain-size classes: -50.0 + 20.0; -40.0 + 20.0; -20.0 + 10.0; -10.0 + 5.0 and 5.0 mm. Methods. The crushing process of granite crushed stone is studied in the conditions of the Kolomoievskyi Granite Quarry, Dnipropetrovsk region. Granite crushed stone with an initial grain-size of 100.0-0.0 mm and strength grade of M1400 is subjected to crushing. The accelerating rotor rotation frequency is the design value n = 200-1200 min-1. Fine crushing of granite is performed in a centrifugal-impact crusher by a free impact in the field of centrifugal forces. Findings. The optimal speed modes of centrifugal crusher operation, which provide the production of high-quality crushed stone with a maximum content of 90-95% cubiform fractions, have been substantiated. Originality. The yield dependences have been obtained of the grain-size classes: -50.0 + 20.0; -40.0 + 20.0; -20.0 + 10.0; -10.0 + 5.0 and 5.0 mm depending on the speed mode of the centrifugal crusher operation. Practical implications. The operating parameters for obtaining the main grain-size classes of cubiform crushed stone from granite have been determined: -50.0 + 20.0; -40.0 + 20.0; -20.0 + 10.0; -10.0 + 5.0 and 5.0 mm. In particular, it has been determined that for the production of cubiform crushed stone with -50.0 + 20.0 mm grain-size, the rotor rotation reasonable speed is 400-500 min-1 (the speed of material departure from the accelerating rotor is 45-50 m/sec); for cubiform crushed stone of -40.0 + 20.0 mm grain-size, the speed mode is 200 min-1 (25 m/sec); for cubiform crushed stone of -20.0 + 10.0 mm grain-size – 600-650 min-1 (70-80 m/sec), respectively. The maximum content of cubiform fractions in the -20.0 + 10.0 mm grain-size class is 95%, which is achieved at a rotor speed of 650-700 min-1 (departure speed is 75-80 m/sec). The maximum content of cubiform fractions in the -10.0 mm grain-size class is 94-95%, which is achieved at the accelerating rotor speed within 700-800 min-1 (departure speed is 70-80 m/sec). The obtained data make it possible to practically choose a rational speed mode of the centri-fugal-impact crusher operation to obtain the maximum yield of cubiform crushed stone.","PeriodicalId":43896,"journal":{"name":"Mining of Mineral Deposits","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2022-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43703685","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-30DOI: 10.33271/mining16.03.096
Ismail Zaki, M. Souissi, A. Larabi
Purpose.The purpose of this paper is to study the characteristics of the carbonate serpentines present at the level of the Ait Ahmane site (Bou Azzer Mine, Morocco). Empirical methods are suitable for analyzing their behavior and determining the dimensions of support types. Methods. The rock mass of different structures mentioned in the study is categorized using empirical methods such RMR, Q-system and AFTES classifications. Findings. It has been found that the use of the rock mass quality method (Q-system) is extremely effective in mining rock mass, based on simulated statistical results obtained using empirical approaches. Originality. The equivalent dimensions of the gallery, the stress state in-situ after mining operations, as well as the height of the overburden are all important factors in the gallery stability. Practical implications. The approach creates a strengthened support structure that is optimal. In addition, this research will be useful as a starting point for geotechnical engineers when designing and planning support systems for tunneling under high in-situ stress conditions for very friable rocks.
{"title":"Study of support types for deposits in contact with serpentines: Ait-Ahmane site","authors":"Ismail Zaki, M. Souissi, A. Larabi","doi":"10.33271/mining16.03.096","DOIUrl":"https://doi.org/10.33271/mining16.03.096","url":null,"abstract":"Purpose.The purpose of this paper is to study the characteristics of the carbonate serpentines present at the level of the Ait Ahmane site (Bou Azzer Mine, Morocco). Empirical methods are suitable for analyzing their behavior and determining the dimensions of support types. Methods. The rock mass of different structures mentioned in the study is categorized using empirical methods such RMR, Q-system and AFTES classifications. Findings. It has been found that the use of the rock mass quality method (Q-system) is extremely effective in mining rock mass, based on simulated statistical results obtained using empirical approaches. Originality. The equivalent dimensions of the gallery, the stress state in-situ after mining operations, as well as the height of the overburden are all important factors in the gallery stability. Practical implications. The approach creates a strengthened support structure that is optimal. In addition, this research will be useful as a starting point for geotechnical engineers when designing and planning support systems for tunneling under high in-situ stress conditions for very friable rocks.","PeriodicalId":43896,"journal":{"name":"Mining of Mineral Deposits","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2022-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43615371","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-30DOI: 10.33271/mining16.03.078
Iaroslav Shavarskyi, V. Falshtynskyi, R. Dychkovskyi, O. Akimov, D. Sala, V. Buketov
Purpose is to study influence of a longwall face advance on the geomechanical situation in the neighbourhood of a mining site based upon determination of changes in standard and critical subsidence of the immediate roof rocks. Methods. To study a geomechanical situation in the neighbourhood of a mining site the authors have applied software product GeoDenamics Lite developed at Dnipro University of Technology. The software product relies upon a calculation procedure of stress-strain state of rocks by Professor O.V. Savostianov. Expediency of the software selection is based upon the supported control and adaptation of a coal mining technique to changes in geodynamic stress fields in the anisotropic rock-coal medium impacting temporal and spatial changes in the technological parameters. Findings. The basic problems have been singled out connected with certain changes in a longwall face advance. For the first time, an analytical scheme of tangential stresses within the immediate roof rocks has been developed for Lisova mine of SE Lvivvuhillia under the conditions of coal seam mining by means of the paired longwalls which makes it possible to determine both physical and geometrical parameters of standard loads within the formation. Originality. Dependencies of temporal and spatial changes in subsidences and horizontal displacements of rock layers of the immediate roof have been defined being 5.2 m for the upper rock pack and 3.9 m for the lower pack if the longwall longwall face advance is 1.9 up to 4.8 m/day. Both physical and geometrical parameters of the reference pressure have been defined as well as the parameters of lower sandstone pack in the process of the main roof subsidence. Impact of the extra pressure forces on the immediate roof rocks has been analyzed at the moment of critical lowerings of the immediate roof rocks. In this context, standard loading from the overlying formation in addition to tangential stresses in the roof result in rock failure due to vertical cracks above a longwall face. Practical implications. The engineering methods have been developed making it possible to identify impact parameters of a longwall face advance on the geomechanical situation in the neighbourhood of a mining site. In future, it will help forecast changes in the reference pressure around a longwall face while preventing emergency settlement of the powered support.
{"title":"Management of the longwall face advance on the stress-strain state of rock mass","authors":"Iaroslav Shavarskyi, V. Falshtynskyi, R. Dychkovskyi, O. Akimov, D. Sala, V. Buketov","doi":"10.33271/mining16.03.078","DOIUrl":"https://doi.org/10.33271/mining16.03.078","url":null,"abstract":"Purpose is to study influence of a longwall face advance on the geomechanical situation in the neighbourhood of a mining site based upon determination of changes in standard and critical subsidence of the immediate roof rocks. Methods. To study a geomechanical situation in the neighbourhood of a mining site the authors have applied software product GeoDenamics Lite developed at Dnipro University of Technology. The software product relies upon a calculation procedure of stress-strain state of rocks by Professor O.V. Savostianov. Expediency of the software selection is based upon the supported control and adaptation of a coal mining technique to changes in geodynamic stress fields in the anisotropic rock-coal medium impacting temporal and spatial changes in the technological parameters. Findings. The basic problems have been singled out connected with certain changes in a longwall face advance. For the first time, an analytical scheme of tangential stresses within the immediate roof rocks has been developed for Lisova mine of SE Lvivvuhillia under the conditions of coal seam mining by means of the paired longwalls which makes it possible to determine both physical and geometrical parameters of standard loads within the formation. Originality. Dependencies of temporal and spatial changes in subsidences and horizontal displacements of rock layers of the immediate roof have been defined being 5.2 m for the upper rock pack and 3.9 m for the lower pack if the longwall longwall face advance is 1.9 up to 4.8 m/day. Both physical and geometrical parameters of the reference pressure have been defined as well as the parameters of lower sandstone pack in the process of the main roof subsidence. Impact of the extra pressure forces on the immediate roof rocks has been analyzed at the moment of critical lowerings of the immediate roof rocks. In this context, standard loading from the overlying formation in addition to tangential stresses in the roof result in rock failure due to vertical cracks above a longwall face. Practical implications. The engineering methods have been developed making it possible to identify impact parameters of a longwall face advance on the geomechanical situation in the neighbourhood of a mining site. In future, it will help forecast changes in the reference pressure around a longwall face while preventing emergency settlement of the powered support.","PeriodicalId":43896,"journal":{"name":"Mining of Mineral Deposits","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2022-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49102431","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Purpose. In safety management, near-miss incident (NMI) reporting has been recognised as an essential practice in the prevention of mining accidents. This research aims to investigate near-miss incidents in Kosovo mining operations based on previous researches and in-situ surveys. Methods. For this purpose, both qualitative and quantitative methods were used as an observation tool, with 115 questionnaires randomly assigned among the employees at mining companies. To analyse collected data, the Excel Spread-Sheet and SPSS software were used. The survey was conducted to get basic information on the number of near-miss incidents, how they occurred and were brought to the light, as well as to reveal their similarity with mining accidents that happened during mining operations in Kosovo. Findings. The research brings to the light that mining activities related to production are the most predominant sources of near-miss incidents. From the qualitative observation approach in different mining companies, it has been found that the majo-rity of mines do not report even in an informal way about near-miss incidents that the employees experience. Originality. The legislative framework of Kosovo does not require a formal reporting on near-miss incidents. Therefore, the present research aims not only to develop proper legislation, but also to comprehensively study the main factors causing near-miss incidents in order to improve mining safety. Increasing the transparency of data on near-miss incidents and their publication should facilitate research work related to improving the safety of mining operations, in other words, the prevention of mining accidents. Practical implications. Apart from the literature review and questionnaire survey conducted in two underground hard rock mines and one surface coal mine, owned and operated by Kosovo authorities, this research attempts to examine sources, influencing factors associated with near-miss incidents, as well as to analyse the best practices of NMI reporting in order to enhance mining safety management in mining sector.
{"title":"Analysis of near-miss incidents (NMI) reporting in mining operations","authors":"Kemajl Zeqiri, Muhamedin Hetemi, Ujmir Uka, Gzim Ibishi, Stojance Mijalkovsk","doi":"10.33271/mining16.03.025","DOIUrl":"https://doi.org/10.33271/mining16.03.025","url":null,"abstract":"Purpose. In safety management, near-miss incident (NMI) reporting has been recognised as an essential practice in the prevention of mining accidents. This research aims to investigate near-miss incidents in Kosovo mining operations based on previous researches and in-situ surveys. Methods. For this purpose, both qualitative and quantitative methods were used as an observation tool, with 115 questionnaires randomly assigned among the employees at mining companies. To analyse collected data, the Excel Spread-Sheet and SPSS software were used. The survey was conducted to get basic information on the number of near-miss incidents, how they occurred and were brought to the light, as well as to reveal their similarity with mining accidents that happened during mining operations in Kosovo. Findings. The research brings to the light that mining activities related to production are the most predominant sources of near-miss incidents. From the qualitative observation approach in different mining companies, it has been found that the majo-rity of mines do not report even in an informal way about near-miss incidents that the employees experience. Originality. The legislative framework of Kosovo does not require a formal reporting on near-miss incidents. Therefore, the present research aims not only to develop proper legislation, but also to comprehensively study the main factors causing near-miss incidents in order to improve mining safety. Increasing the transparency of data on near-miss incidents and their publication should facilitate research work related to improving the safety of mining operations, in other words, the prevention of mining accidents. Practical implications. Apart from the literature review and questionnaire survey conducted in two underground hard rock mines and one surface coal mine, owned and operated by Kosovo authorities, this research attempts to examine sources, influencing factors associated with near-miss incidents, as well as to analyse the best practices of NMI reporting in order to enhance mining safety management in mining sector.","PeriodicalId":43896,"journal":{"name":"Mining of Mineral Deposits","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2022-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43913608","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-30DOI: 10.33271/mining16.03.067
A. Peremetchyk, O. Kulikovska, Nataliia Shvaher, Serhii Chukhareva, S. Fedorenko, R. Moraru, V. Panayotov
Purposeis development of the methods to predict indices of iron-ore deposits relying upon the improvement of available techniques as well as formulation of new geometrization procedures and identification of the most adequate decision-making way to assess geological data as the basis for geometrization and prediction. Methods are to develop a self-organizing prediction algorithm based upon combination of the available techniques and formulation of new mathematical methods; consider various means to assess them in the context of iron-ore deposit; and select the most efficient one. Use of geostatistical methods makes it possible to evaluate and process output geological information. The methods help assess mineral reserves of a mining enterprise. Findings. Dependencies of magnetite ore content upon geological factors have been derived in the context of an open pit of PIVDGZK JSC. The deposit has been geometrized; predictive mining and geometric model of the deposit site has been deve-loped. Factors have been determined influencing the distribution nature of the indices. Graphs to arrange grade indices of the deposit have been constructed. The graphs have helped predict their placement within the deposit. Originality. A method to predict mining and geological indices of iron-ore deposit has been developed relaying upon a self-organizing algorithm. Correlation between grade indices of minerals and different geological factors has been determined making it possible to describe spatial distribution of grade indices of the deposit. Practical implications. Geometrization methods for iron-ore deposits have been formulated. The methods help schedule mining operations accurately while improving their efficiency. The developed predictive self-organizing algorithm is the flexible tool used for various mining and geological conditions to provide scheduling and assessing of different mining methods. The self-organizing as well as geostatic evaluation techniques is quite a promising research tendency.
{"title":"Predictive geometrization of grade indices of an iron-ore deposit","authors":"A. Peremetchyk, O. Kulikovska, Nataliia Shvaher, Serhii Chukhareva, S. Fedorenko, R. Moraru, V. Panayotov","doi":"10.33271/mining16.03.067","DOIUrl":"https://doi.org/10.33271/mining16.03.067","url":null,"abstract":"Purposeis development of the methods to predict indices of iron-ore deposits relying upon the improvement of available techniques as well as formulation of new geometrization procedures and identification of the most adequate decision-making way to assess geological data as the basis for geometrization and prediction. Methods are to develop a self-organizing prediction algorithm based upon combination of the available techniques and formulation of new mathematical methods; consider various means to assess them in the context of iron-ore deposit; and select the most efficient one. Use of geostatistical methods makes it possible to evaluate and process output geological information. The methods help assess mineral reserves of a mining enterprise. Findings. Dependencies of magnetite ore content upon geological factors have been derived in the context of an open pit of PIVDGZK JSC. The deposit has been geometrized; predictive mining and geometric model of the deposit site has been deve-loped. Factors have been determined influencing the distribution nature of the indices. Graphs to arrange grade indices of the deposit have been constructed. The graphs have helped predict their placement within the deposit. Originality. A method to predict mining and geological indices of iron-ore deposit has been developed relaying upon a self-organizing algorithm. Correlation between grade indices of minerals and different geological factors has been determined making it possible to describe spatial distribution of grade indices of the deposit. Practical implications. Geometrization methods for iron-ore deposits have been formulated. The methods help schedule mining operations accurately while improving their efficiency. The developed predictive self-organizing algorithm is the flexible tool used for various mining and geological conditions to provide scheduling and assessing of different mining methods. The self-organizing as well as geostatic evaluation techniques is quite a promising research tendency.","PeriodicalId":43896,"journal":{"name":"Mining of Mineral Deposits","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2022-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43537829","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-30DOI: 10.33271/mining16.03.048
S. Saptono, Danu Mirza Rezky
Purpose. The behavior of slope instability is influenced by many factors, both internal, such as the physical-mechanical properties of materials, and external, such as rain and seismic activity. Sensitivity analysis is used to determine the parameters that have the greatest impact on the level of slope stability. Methods. Sensitivity analysis of embankment slopes uses the coefficient of variation (CV) approach with input parameters namely cohesion and internal friction angle. Findings. The results of the study confirm that the internal friction angle is the most influential parameter on the embankment slope stability. The evidence is that at the highest percentage of CV, there is the highest probability of avalanches, based on these parameters. Originality. In this research, the coefficient of variation method is used to determine which parameters have heterogeneous data distribution and the greatest probability of failure, as well as to test mechanical sensitivity with the concept of changing the percentage of parameters to a safety factor value to validate calculations using the coefficient of variation approach. Practical implications. The sensitivity analysis results are not only limited to values, since the more important is finding out the cause of the influence of these parameters according to field conditions. The reason why the internal friction angle is the most sensitive parameter is the grain size approach, when the limestone mixture in the field has coarse and large grain sizes. Therefore, the surface tends to form rough waves and causes the relatively large grained rocks to have large internal friction angles.
{"title":"Sensitivity analysis of nickel haul road embankment slopes using the coefficient of variation approach","authors":"S. Saptono, Danu Mirza Rezky","doi":"10.33271/mining16.03.048","DOIUrl":"https://doi.org/10.33271/mining16.03.048","url":null,"abstract":"Purpose. The behavior of slope instability is influenced by many factors, both internal, such as the physical-mechanical properties of materials, and external, such as rain and seismic activity. Sensitivity analysis is used to determine the parameters that have the greatest impact on the level of slope stability. Methods. Sensitivity analysis of embankment slopes uses the coefficient of variation (CV) approach with input parameters namely cohesion and internal friction angle. Findings. The results of the study confirm that the internal friction angle is the most influential parameter on the embankment slope stability. The evidence is that at the highest percentage of CV, there is the highest probability of avalanches, based on these parameters. Originality. In this research, the coefficient of variation method is used to determine which parameters have heterogeneous data distribution and the greatest probability of failure, as well as to test mechanical sensitivity with the concept of changing the percentage of parameters to a safety factor value to validate calculations using the coefficient of variation approach. Practical implications. The sensitivity analysis results are not only limited to values, since the more important is finding out the cause of the influence of these parameters according to field conditions. The reason why the internal friction angle is the most sensitive parameter is the grain size approach, when the limestone mixture in the field has coarse and large grain sizes. Therefore, the surface tends to form rough waves and causes the relatively large grained rocks to have large internal friction angles.","PeriodicalId":43896,"journal":{"name":"Mining of Mineral Deposits","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2022-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42865466","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-30DOI: 10.33271/mining16.03.086
S. El-shafei, F. Ramadan, M. Essawy, A. Henaish, B. Nabawy
Purpose.This paper aims to understand the genesis and nature of the manganese ore deposits associated with the Ras Samra Member of the Um Bogma Formation in the southwest of Sinai. Methods. Mineralogical and geochemical studies of 50 selected samples of manganese ores and host shale have been conducted. These samples have been taken from different sites representing the Ras Samra Member. Findings. The dominant manganese minerals are pyrolusite and hausmannite. In most samples, helvite and hematite are noted in association with pyrolusite. In the investigated manganese ores, wide ranges of MnO (17.70-81.90 wt. %) and Fe2O3 (1.16-65.49 wt. %) concentrations are observed. Based on their Mn/Fe ratio, they can be classified into high-Mn ore content (76.94-6.46%), medium-Mn ore content (4.87-2.58%), and low-Mn ore content (1.51-0.30%). Originality. The compositions of major and trace elements in Ras Samra manganese ores, together with their textures and mineralogical compositions, suggest an epigenetic hydrothermal contribution for high-Mn ores, as well as syngenetic sedimentary precipitation for medium- Mn and low-Mn ores. The epigenetic nature of the high-Mn samples may be related to a younger phase of hydrothermal activity associated with Tertiary basalt flows. Ore-bearing hypogene solutions, which penetrate the bedding planes, have impregnated and cemented non-diagenetic terrigenous sandstones and shale. Practical implications. In contrast to low-Mn ores, high-Mn and medium-Mn ores of Um Bogma are preferable for obtai-ning a significant economic effect in the production of ferromanganese alloys. However, low-Mn ores need to be processed appropriately to achieve the desired quality in order to meet the present level of manganese demand in Egypt.
{"title":"Geology, mineralogy and geochemistry of manganese ore deposits of the Um Bogma Formation, south-western Sinai, Egypt: genesis implications","authors":"S. El-shafei, F. Ramadan, M. Essawy, A. Henaish, B. Nabawy","doi":"10.33271/mining16.03.086","DOIUrl":"https://doi.org/10.33271/mining16.03.086","url":null,"abstract":"Purpose.This paper aims to understand the genesis and nature of the manganese ore deposits associated with the Ras Samra Member of the Um Bogma Formation in the southwest of Sinai. Methods. Mineralogical and geochemical studies of 50 selected samples of manganese ores and host shale have been conducted. These samples have been taken from different sites representing the Ras Samra Member. Findings. The dominant manganese minerals are pyrolusite and hausmannite. In most samples, helvite and hematite are noted in association with pyrolusite. In the investigated manganese ores, wide ranges of MnO (17.70-81.90 wt. %) and Fe2O3 (1.16-65.49 wt. %) concentrations are observed. Based on their Mn/Fe ratio, they can be classified into high-Mn ore content (76.94-6.46%), medium-Mn ore content (4.87-2.58%), and low-Mn ore content (1.51-0.30%). Originality. The compositions of major and trace elements in Ras Samra manganese ores, together with their textures and mineralogical compositions, suggest an epigenetic hydrothermal contribution for high-Mn ores, as well as syngenetic sedimentary precipitation for medium- Mn and low-Mn ores. The epigenetic nature of the high-Mn samples may be related to a younger phase of hydrothermal activity associated with Tertiary basalt flows. Ore-bearing hypogene solutions, which penetrate the bedding planes, have impregnated and cemented non-diagenetic terrigenous sandstones and shale. Practical implications. In contrast to low-Mn ores, high-Mn and medium-Mn ores of Um Bogma are preferable for obtai-ning a significant economic effect in the production of ferromanganese alloys. However, low-Mn ores need to be processed appropriately to achieve the desired quality in order to meet the present level of manganese demand in Egypt.","PeriodicalId":43896,"journal":{"name":"Mining of Mineral Deposits","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2022-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48631566","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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