Journal & Issues

Volume 28 (2022): Issue 4 (December 2022)

Volume 28 (2022): Issue 3 (September 2022)

Volume 28 (2022): Issue 2 (June 2022)

Volume 28 (2022): Issue 1 (March 2022)

Volume 27 (2021): Issue 4 (December 2021)

Volume 27 (2021): Issue 3 (September 2021)

Volume 27 (2021): Issue 2 (June 2021)

Volume 27 (2021): Issue 1 (March 2021)

Journal Details
Format
Journal
eISSN
2247-8590
First Published
20 Mar 2021
Publication timeframe
4 times per year
Languages
English

Search

Volume 28 (2022): Issue 1 (March 2022)

Journal Details
Format
Journal
eISSN
2247-8590
First Published
20 Mar 2021
Publication timeframe
4 times per year
Languages
English

Search

7 Articles
Open Access

Monitoring of Tunnel Rock Mass Deformations During Provisional Support Stage: A Case Study

Published Online: 13 Apr 2022
Page range: 1 - 23

Abstract

Abstract

The present study evaluates on site the effects of provisional support on the rate of deformation (convergence) of clay-stone of a twin-tube tunnel. The combination of shotcrete, steel lattice, steel retaining, pre-supporting iron bar and Rock bolts can act as structural support in the form of provisional support for new or existing tunnels. Applications of provisional supports as confinement mechanisms to decrease the capacity of convergence can be helpful for distressed rock mass during tunnels digging. Real-size and real-time field monitoring over a period of approximately one (01) year was carried out with a Tachometer “Leica, TS 09” and 3D Displacement Monitoring Objectives fixed on the top heading and on the invert/bench. Wherefore; a sketch of the same cross-section of the tunnel was used in order to define the deformations of the rock mass of the tunnel measured in 3D in successive periods in all directions along the weak rock mass of the fourth class (IV) after the installation of the provisional support. The study shows good results in terms of deformation of the rock mass of the tunnel and satisfactory stability in terms of confinement. Consequently; it was noticed, that there is a relation between the deformations (convergence) in the two tubes along tunnel - when the deformation of the left tube increases the deformation of the right tube decreases -, and that the deformation of the tunnel is a deformation overall of the rock mass and it is the same along the tunnel relative to its rock mass. It can be concluded that there is a reciprocal effect between the two tunnel tubes, which can be considered as a conservation principle of the rock mass.

Keywords

  • Twin Tube Tunnel
  • Clay-Stone
  • Provisional Support
  • Deformations
  • Monitoring
Open Access

Investigation of the Causes and Factors Generating Land Instability in the Berbeşti Mining Basin

Published Online: 13 Apr 2022
Page range: 24 - 36

Abstract

Abstract

Romania’s new commitments to give up coal-based energy production entail the gradual closure of the last four open-pits in operation in Berbești Mining Basin, thus, raising the issue of primarily ensuring the stability of the lands in these perimeters in order to reintroduce them, too, into the economic circuit as soon as possible. Considering the numerous negative geo-mining phenomena that have taken place over time in the perimeters of Berbești Mining Basin, respectively landslides and other types of geotechnical phenomena, it is necessary to investigate the causes and factors that favor their manifestation so that their influence can be reduced, removed or simply taken into resizing calculations. The paper presents the results of a study whose purpose is to investigate the factors and causes that generate phenomena of instability of natural and artificial slopes in the area of Berbești Mining Basin. The main research methods applied in this paper were in situ observations, analyzes and laboratory tests, identification of rock types and their behaviors in various weather and humidity conditions, determination of physical and mechanical characteristics, and interpretation of results.

Keywords

  • causes
  • factors
  • stability
  • landslides
  • Berbești
Open Access

Determinations and Interpretations of Heavy Metal Analysis in the Sediments and Water of Cavnic and Lăpuş Rivers

Published Online: 13 Apr 2022
Page range: 37 - 41

Abstract

Abstract

The article presents laboratory analysis of the water and sediment samples taken on September 2021 from Cavnic and Lăpuș rivers. The values of these results are interpreted by reference to the Technical Regulations on heavy metal contents in discharged waters into the emissary, without being able to be reported on regulations on river sediments. An analysis is made of the impact of these contents leading to complete destruction of aquatic life in the areas of sampling.

Keywords

  • Water sample
  • sediment sample
  • heavy metals
  • pollution
Open Access

Study and Enhancement of Underground Mining Technologies to Prevent Earth’s Surface Failures

Published Online: 13 Apr 2022
Page range: 42 - 49

Abstract

Abstract

The work contains studies of the problem of stabilizing geodynamic processes in the rock massif, preservation of the daylight surface and ecological balance in the mined-out and operating mine fields of Ukraine. The main regularities of influence of sublevel-room mining systems with backfilling on changes of the stress-strain state of the rock massif and the main structural elements of the block are determined.

Rich iron ore mining by underground methods and subsequent transition to the sublevel-room mining system with backfilling is modeled. New technologies for mining ore deposits are developed and current ones are enhanced to prevent the earth’s surface failures, stabilize landslide and displacement zones within the boundaries existing at the time of transition to systems with backfilling. The developed resource-saving technologies of mining can significantly enhance ore extraction indicators and the environmental condition of the basin by locating waste dumps and disposing wastes of mining enterprises in the mined-out area of underground mines.

Keywords

  • underground mining
  • stress-strain state
  • rich iron ores
  • magnetite quartzite
  • ore drawing
  • flowsheet
Open Access

Water Quality Monitoring in Valea Jiului

Published Online: 13 Apr 2022
Page range: 50 - 65

Abstract

Abstract

The paper presents the monitoring of the water quality in Valea Jiului, related to the Jiu river basin. In the increasingly alert conditions of urbanization and industrialization, contemporary civilization is characterized by a worrying process of deteriorating the ecological balance and pollution of water resources. Monitoring allows the achievement of four primary objectives in knowing the state of water quality, namely: monitoring, forecasting, warning and intervention. The paper presents the objectives of water quality monitoring, aspects related to the implementation of water monitoring programs.

Keywords

  • monitoring
  • water quality
  • Valea Jiului
Open Access

Evaluation of Air Pollution as a Result of Coal Exploitation in Roşiuţa Coal Pit

Published Online: 13 Apr 2022
Page range: 66 - 72

Abstract

Abstract

The polluting activity carried out by the coal exploitation in Roşiuţa coal pit has effects on the environment and the main pollution sources of the atmosphere are: suspended powders, particulate matter and burning gases. The pollutants contain substances with different degrees of toxicity. Through the measurements performed “in situ”, for the dust concentration at different points, it was found that the indices of the maximum concentration (MC-mg/m3/air), on the mining areas, were according to the legislation in force. At some points, the dust concentration is higher, but as the distance increases, the pollution is no longer felt, so it can be noticed that the lignite exploitation has a local influence.

Keywords

  • air pollution
  • coal pit
  • sterile dump
  • coal yard
  • Roșiuța
Open Access

Past and Present Climate Conditions of European Coal and Lignite Areas

Published Online: 13 Apr 2022
Page range: 73 - 86

Abstract

Abstract

Weather and climate are parameters vital for the development and flourish of human activities, and they crucially affect mining activities. Coal and lignite (brown coal) mining operations can be aided by appropriate weather or stopped by an extreme weather event that might have catastrophic consequences for a mining area. The same stands for closed and abandoned coal mines, as extreme weather events can have severe consequences. This work aims to obtain a comprehensive overview of the climatic conditions by documenting and reporting them in various European coal and lignite mining regions. Specifically, the chosen regions cover Europe from the north (the United Kingdom) to the south (Greece), from the east (Poland, the Czech Republic) to the west (Spain), and through Europe’s center (Germany). A climate baseline is created for the chosen regions to serve as a reference for safety assessment and for evaluating future climate changes. Initially, the general climate of each region was evaluated; additionally, an extensive climate database from 1990 to 2020 was created, including the mean annual temperature and precipitation. Mean values and general trends of increase or decrease during the last 30 years are of interest and were compared for all areas.

Keywords

  • coal mines
  • lignite mines
  • climate conditions
  • precipitation
  • temperature
7 Articles
Open Access

Monitoring of Tunnel Rock Mass Deformations During Provisional Support Stage: A Case Study

Published Online: 13 Apr 2022
Page range: 1 - 23

Abstract

Abstract

The present study evaluates on site the effects of provisional support on the rate of deformation (convergence) of clay-stone of a twin-tube tunnel. The combination of shotcrete, steel lattice, steel retaining, pre-supporting iron bar and Rock bolts can act as structural support in the form of provisional support for new or existing tunnels. Applications of provisional supports as confinement mechanisms to decrease the capacity of convergence can be helpful for distressed rock mass during tunnels digging. Real-size and real-time field monitoring over a period of approximately one (01) year was carried out with a Tachometer “Leica, TS 09” and 3D Displacement Monitoring Objectives fixed on the top heading and on the invert/bench. Wherefore; a sketch of the same cross-section of the tunnel was used in order to define the deformations of the rock mass of the tunnel measured in 3D in successive periods in all directions along the weak rock mass of the fourth class (IV) after the installation of the provisional support. The study shows good results in terms of deformation of the rock mass of the tunnel and satisfactory stability in terms of confinement. Consequently; it was noticed, that there is a relation between the deformations (convergence) in the two tubes along tunnel - when the deformation of the left tube increases the deformation of the right tube decreases -, and that the deformation of the tunnel is a deformation overall of the rock mass and it is the same along the tunnel relative to its rock mass. It can be concluded that there is a reciprocal effect between the two tunnel tubes, which can be considered as a conservation principle of the rock mass.

Keywords

  • Twin Tube Tunnel
  • Clay-Stone
  • Provisional Support
  • Deformations
  • Monitoring
Open Access

Investigation of the Causes and Factors Generating Land Instability in the Berbeşti Mining Basin

Published Online: 13 Apr 2022
Page range: 24 - 36

Abstract

Abstract

Romania’s new commitments to give up coal-based energy production entail the gradual closure of the last four open-pits in operation in Berbești Mining Basin, thus, raising the issue of primarily ensuring the stability of the lands in these perimeters in order to reintroduce them, too, into the economic circuit as soon as possible. Considering the numerous negative geo-mining phenomena that have taken place over time in the perimeters of Berbești Mining Basin, respectively landslides and other types of geotechnical phenomena, it is necessary to investigate the causes and factors that favor their manifestation so that their influence can be reduced, removed or simply taken into resizing calculations. The paper presents the results of a study whose purpose is to investigate the factors and causes that generate phenomena of instability of natural and artificial slopes in the area of Berbești Mining Basin. The main research methods applied in this paper were in situ observations, analyzes and laboratory tests, identification of rock types and their behaviors in various weather and humidity conditions, determination of physical and mechanical characteristics, and interpretation of results.

Keywords

  • causes
  • factors
  • stability
  • landslides
  • Berbești
Open Access

Determinations and Interpretations of Heavy Metal Analysis in the Sediments and Water of Cavnic and Lăpuş Rivers

Published Online: 13 Apr 2022
Page range: 37 - 41

Abstract

Abstract

The article presents laboratory analysis of the water and sediment samples taken on September 2021 from Cavnic and Lăpuș rivers. The values of these results are interpreted by reference to the Technical Regulations on heavy metal contents in discharged waters into the emissary, without being able to be reported on regulations on river sediments. An analysis is made of the impact of these contents leading to complete destruction of aquatic life in the areas of sampling.

Keywords

  • Water sample
  • sediment sample
  • heavy metals
  • pollution
Open Access

Study and Enhancement of Underground Mining Technologies to Prevent Earth’s Surface Failures

Published Online: 13 Apr 2022
Page range: 42 - 49

Abstract

Abstract

The work contains studies of the problem of stabilizing geodynamic processes in the rock massif, preservation of the daylight surface and ecological balance in the mined-out and operating mine fields of Ukraine. The main regularities of influence of sublevel-room mining systems with backfilling on changes of the stress-strain state of the rock massif and the main structural elements of the block are determined.

Rich iron ore mining by underground methods and subsequent transition to the sublevel-room mining system with backfilling is modeled. New technologies for mining ore deposits are developed and current ones are enhanced to prevent the earth’s surface failures, stabilize landslide and displacement zones within the boundaries existing at the time of transition to systems with backfilling. The developed resource-saving technologies of mining can significantly enhance ore extraction indicators and the environmental condition of the basin by locating waste dumps and disposing wastes of mining enterprises in the mined-out area of underground mines.

Keywords

  • underground mining
  • stress-strain state
  • rich iron ores
  • magnetite quartzite
  • ore drawing
  • flowsheet
Open Access

Water Quality Monitoring in Valea Jiului

Published Online: 13 Apr 2022
Page range: 50 - 65

Abstract

Abstract

The paper presents the monitoring of the water quality in Valea Jiului, related to the Jiu river basin. In the increasingly alert conditions of urbanization and industrialization, contemporary civilization is characterized by a worrying process of deteriorating the ecological balance and pollution of water resources. Monitoring allows the achievement of four primary objectives in knowing the state of water quality, namely: monitoring, forecasting, warning and intervention. The paper presents the objectives of water quality monitoring, aspects related to the implementation of water monitoring programs.

Keywords

  • monitoring
  • water quality
  • Valea Jiului
Open Access

Evaluation of Air Pollution as a Result of Coal Exploitation in Roşiuţa Coal Pit

Published Online: 13 Apr 2022
Page range: 66 - 72

Abstract

Abstract

The polluting activity carried out by the coal exploitation in Roşiuţa coal pit has effects on the environment and the main pollution sources of the atmosphere are: suspended powders, particulate matter and burning gases. The pollutants contain substances with different degrees of toxicity. Through the measurements performed “in situ”, for the dust concentration at different points, it was found that the indices of the maximum concentration (MC-mg/m3/air), on the mining areas, were according to the legislation in force. At some points, the dust concentration is higher, but as the distance increases, the pollution is no longer felt, so it can be noticed that the lignite exploitation has a local influence.

Keywords

  • air pollution
  • coal pit
  • sterile dump
  • coal yard
  • Roșiuța
Open Access

Past and Present Climate Conditions of European Coal and Lignite Areas

Published Online: 13 Apr 2022
Page range: 73 - 86

Abstract

Abstract

Weather and climate are parameters vital for the development and flourish of human activities, and they crucially affect mining activities. Coal and lignite (brown coal) mining operations can be aided by appropriate weather or stopped by an extreme weather event that might have catastrophic consequences for a mining area. The same stands for closed and abandoned coal mines, as extreme weather events can have severe consequences. This work aims to obtain a comprehensive overview of the climatic conditions by documenting and reporting them in various European coal and lignite mining regions. Specifically, the chosen regions cover Europe from the north (the United Kingdom) to the south (Greece), from the east (Poland, the Czech Republic) to the west (Spain), and through Europe’s center (Germany). A climate baseline is created for the chosen regions to serve as a reference for safety assessment and for evaluating future climate changes. Initially, the general climate of each region was evaluated; additionally, an extensive climate database from 1990 to 2020 was created, including the mean annual temperature and precipitation. Mean values and general trends of increase or decrease during the last 30 years are of interest and were compared for all areas.

Keywords

  • coal mines
  • lignite mines
  • climate conditions
  • precipitation
  • temperature

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