Mine Walls Research Articles

Bat-associated ticks as a potential link for vector-borne pathogen transmission between bats and other animals.

Potentially zoonotic pathogens have been previously detected in bat-associated ticks, but their role in disease transmission and their frequency of feeding on non-bat hosts is poorly known. We used molecular blood meal analysis to reveal feeding patterns of the bat-associated tick species Ixodes ariadnae, I. simplex, and I. vespertilionis collected from cave and mine walls in Central and Southeastern Europe. Vertebrate DNA, predominantly from bats, was detected in 43.5% of the samples (70 of 161 ticks) but in these ticks we also detected the DNA of non-chiropteran hosts, such as dog, Canis lupus familiaris, wild boar, Sus scrofa, and horse, Equus caballus, suggesting that bat-associated ticks may exhibit a much broader host range than previously thought, including domestic and wild mammals. Furthermore, we detected the zoonotic bacteria Neoehrlichia mikurensis in bat ticks for the first time, and other bacteria, such as Bartonella and Wolbachia. In the light of these findings, the role of bat ticks as disease vectors should be urgently re-evaluated in more diverse host systems, as they may contribute to pathogen transmission between bats and non-chiropteran hosts.

Investigation of human interaction with an augmented remote operating system for scaling in mining applications

Thanks to the advent of telepresence applications, we can remotely take control and operate industrial machinery. Teleoperation removes operators from hazardous workplaces such as mining and plays an essential role in the safety of workers. In addition, augmented telepresence can introduce information that helps the user understand the remote scene. However, remote operation presents challenges since the information received is more limited than what could be perceived by being physically present, such as accurately judging depth. This study investigates how well operators interact with an augmented remote operation scaling system (AROSS) in a mining context when different computer-generated visual interfaces are provided. The system can achieve five visual interfaces: Disocclusion Augmentation view using selective content removal, Novel Perspective view generation, Lidar view, Right (Original) view, and Left (Original) view. We performed two experiments in a mine-like laboratory to analyze human interaction with the designed prototype by applying a mixed research methodology that used questionnaires, interviews, and observations. This mixed methodology consisted of quality of experience methods to discover the users’ requirements from a technological standpoint and user experience methods (i.e., user-centric approaches). We investigated 10 and 11 users’ interactions in two experimental studies. The first experiment focused on identifying small patterns (e.g., cracks in the mine wall), and the second focused on depth and three-dimensional understanding. We considered the first experiment a feasibility test to understand how to conduct the second experiment. Therefore, we designed the second test to assess the technical readiness of AROSS from the users’ perspective. The overall conclusion yields a comprehensive understanding of users’ perceptions and experiences. The quality of experience results favored Left and Right (Original) views for remote control, indicating a preference among remote operators using natural (Original) views due to their facilitation of environmental comprehension. User experience analysis revealed the reason why other views were less favored and what their potential benefits are. Specifically, Novel Perspective and Lidar views were found helpful for depth perception, and Disocclusion Augmentation view functionality could be enhanced if robot arm position tracking is enabled. These insights inform design recommendations, emphasizing the value of incorporating Disocclusion Augmentation and Novel Perspective views and suggesting improvements to enhance system usability.

Study of Slope Stability of the Mining Wall in an Open-Pit Coal Mine by the Paste Cut-and-Backfill Method

According to this study’s findings, slope stability problems in open-pit coal mines can be avoided, and mine wall collapse can be effectively mitigated by the use of cut-and-backfill mining techniques. The main research results are as follows: (1) The stope and waste rock’s geotechnical, physical, and mechanical characteristics were gathered and examined; the geotechnical and mechanical characteristics found in this study largely satisfy the criteria for slope stability analysis. (2) Cemented paste backfill (CPB) materials were made of mine waste rock and fly ash at a desired ratio, mixed with cement as a bond material, and were tested in the laboratory, using a combination of cement percentages of 6%, 8%, and 10% for the cement content and 25%, 30%, 35%, and 40% for the fly ash content, to determine the ideal mix for artificial ground support in underground mines, taking into account both economic and performance factors. (3) By using this model, the changes in CPB strength were investigated under various factors influencing the cement ratio, and limit equilibrium modeling was used with the FLAC-Slope 8.1 program with different cement paste backfill ratio to calculate the factor of safety for each cement percentage after 1 day, 3 days, 7 days, and 28 days of curing time (CT) to obtain the optimum compressive strength and shear straight of cemented paste backfill with high paste fill shear strength on the slope. (4) The research results are of great significance for the safety of important facilities in open-pit mines and provide a basis for the design and safety implementation of open-pit slope engineering.

Stability Analysis of a Mine Wall Based on Different Roof-Contact Filling Rates

This study takes the mine wall of the isolated mine pillar in the Dongguashan Copper Mine as the research object. Based on the mechanical model of the mine wall under the trapezoidal loading of the backfill, the expressions for calculating the safety factor of the mine wall were derived by considering the load-bearing conditions of the backfill–mine-wall system under different roof-contacted filling rates. On this basis, the variation law of the safety factor of the mine wall with the roof-contacted filling rate was obtained, and the calculation result was verified by a numerical simulation and a field test. The research shows that for the same mine wall width, when the roof-contacted filling rate exceeds 9.53%, the safety factor of the mine wall exhibits a "trapezoidal" variation pattern with the increase in the roof-contacted filling rate. Moreover, the comprehensive benefits of isolated pillar recovery are made more credible by maintaining a wall width of 3 m and a filler jointing rate between 30% and 74.49%. This study analyzes the effect of the roof-contacted filling rate on the stability of the mine wall, which can provide a theoretical basis for mining isolated pillars by the filler method in deep mines.

Three-Dimensional Geologic Modeling of the Kiruna Mining District, Sweden: Insights into the Crustal Architecture and Structural Controls on Iron Oxide-Apatite Mineralization

Abstract To support economic decisions and exploration targeting, as well as to understand processes controlling the mineralization, three-dimensional structural and lithological boundary models of the Kiruna mining district have been built using surface (outcrop observations and measurements) and subsurface (drill hole data and mine wall mapping) data. Rule-based hybrid implicit-explicit modeling techniques were used to create district-scale models of areas with high disproportion in data resolution characterized by dense, clustered, and distant data spacing. Densely sampled areas were integrated with established conceptual studies using geologic conditions and the addition of synthetic data, leading to variably constrained surfaces that facilitate the visualization, interpretation, and further integration of the geologic models. This modeling approach proved to be efficient in integrating local, frequently sampled areas with district-scale, sparsely sampled regions. Dominantly S-plunging lineation on N-S–trending fracture planes, characteristic fracture mineral-fill, and weak rock mass at the ore contact indicated by poor core orientation quality and rock quality description suggest that ore-parallel fractures in the Kiirunavaara area were more commonly reactivated. Slight variation in the angular relationship of fracture sets situated in different fault-bound blocks suggests that strain accommodation across the orebodies was uneven. The location of brittle faults identified in drill core, deposit-scale structural analysis, and aeromagnetic geophysical maps indicate a close relationship between fault locations and the iron oxide-apatite mineralization, suggesting that uneven stress accommodation and proximity of conjugate fault sets played an important role in juxtaposing blocks from different crustal depths and controls the location of the iron oxide-apatite orebodies.

Development of a finite element groundwater flow model to test drainage management strategies for the expansion of the Dareh-Zar open pit mine, Iran

A finite-element groundwater flow model was developed for the expanding Dareh-Zar open pit mine in southern Iran, to simulate groundwater inflow into the excavation and mine wall pore pressure dynamics. The model was used to test the effectiveness of implementing different drainage management strategies to reduce groundwater inflow rates and mine wall pore pressures, including abstraction wells and horizontal drains. Model predictions suggest the implementation of abstraction wells will reduce groundwater inflow rates by 75% during the first 12 years of mining and 50% during the subsequent 5 years relative to a ‘no drainage’ management scenario, with further reductions in groundwater inflow achieved through horizontal drain installation. Furthermore, the installation of horizontal drains was found to be necessary to reduce mine-wall pore pressures from destabilizing the mine walls. Groundwater management of the decommissioned pit mine was also evaluated, with simulation results suggesting that backfilling the excavation would restore the groundwater level within the open pit mine region to ~2,442 m above sea level, representing a net restoration of ~204 m relative to the water table prior to mine closure.

Slope stability analysis of an open pit mine with considering the weathering agent: Field, laboratory and numerical studies

Freezing-thawing (F-T) processes can affect the slope instability of open pit mine wall in cold regions, resulting the increase of mining operations cost and decrease the safety of personnel and equipment. Therefore, estimating the degradation of rockmass geomechanical properties under the weathering agent is crucial for slope stability analysis of an open pit mine in mountain areas. Accordingly, for optimal slope stability analysis of Angouran open-pit mine in this research, variations of physico-mechanical properties of pit wall schist rock including dry density, and uniaxial and triaxial compressive strengths were firstly measured during the defined F-T cycles. Then, the related properties of slope rock mass were determined using the generalized Hoek-Brown criterion. Based on the estimated rock mass characteristics, a numerical model of mine slope was constructed and pit stability conditions was analyzed. According to the obtained results, the displacement of slope rock mass varied from 0 to 14.6 m, occurred in highly weathered schist, indicating the low probability of large collapses. To validate the achieved results, 30 prisms were installed in the north-west wall of mine and in-situ displacements were recorded three times in week for one year. Results indicated that the measured displacements from in-situ monitoring and numerical model are in good agreement, so that the determination coefficient (R2) was obtained 0.80.

TIME SERIES INSAR ANALYSIS FOR SLOPE STABILITY MONITORING USING SENTINEL-1 IN OPEN PIT MINING

Abstract. Surface mining is an important economic activity in many regions where mineral resources are located close to the surface. The process of ore extraction is characterised by high pit walls with steep slopes. The mining process introduces significant stress and strain changes that could lead to movement on the slope face. Slope failure on the pit walls can occur without warning and can lead to loss of life and disruptions to the mining process. The monitoring of slopes remains the most reliable way to detect movement on unstable slopes. Therefore, slope monitoring programmes have been established to monitor and measure slope movement to help mine management with the stability status of open pit slopes. Conventional monitoring techniques include visual inspections and in situ instrumentation that are point-based, time-consuming, and costly. Open-source remote sensing techniques such as Synthetic Aperture Radar interferometry have been used to monitor slope movements on open-pit mine walls. Time series interferometric Synthetic Aperture Radar (InSAR) can be used to overcome limitations of in-situ monitoring for monitoring slope movements in open-pit mines.

FEATURES OF GEOMORPHOLOGY STRUCTURE OF THE GNIVAN GRANITE QUARRY (VINNYTSIA REGION)

The Hnivan granite quarry is located in Vinnytsia district of Vinnytsia region. Geomorphologically, territory belongs to the western edge of the Dnieper Upland. Geostructurally, the quarry is located on the western edge of the Ukrainian shield, within the Podilsky megablock. Since the beginning of development, 7 rock horizons have been fully opened. As of today, the 8th horizon is being developed, and the development of the 9th horizon is planned in the future. The Hnivan quarry is a deep polygonal trapezoidal quarry in plan with many steps in profile. Morphometric characteristics of the Hnivan quarry and dump complex: the maximum length from north to south (including dumps of overburden strata) is 1 800 m; the maximum length of the quarry pit from north to south is 1 400 m, the maximum width from west to east is 900 m. The absolute heights within the mining are 230–255 m, the absolute height of the mine floor is 130 m. The depth of the quarry pit is currently about 105 m. The bottom is 97 meters below the level of the Southern Buh river. Quarry landforms are divided into produced relief forms, caused by anthropogenic denudation and bulked relief forms, created as a result of anthropogenic accumulation. The produced relief of the Hnivan quarry is represented by the bottom and walls. The bottom has a complex geometric shape of an elongated polygon from north to south. It consists of the bottom of the seventh developed horizon and the eighth horizon, where mining operations are carried out. Between these horizons, there is a step 15 m high. The surface of the bottom is flat, there are no internal dumps. The walls of the quarry are characterized by a multi-step shape in profile. They are approximately the same in height, steepness and nature of the processes. The structure of the walls in the upper parts, which are represented by ledges of overburden horizons, is different. The ancient steps of the mine walls are significantly disturbed by weathering, water erosion and gravitational processes. The produced relief forms of the quarry are represented by overburden dumps and processing plant dumps. All of them are located outside the quarry and are external dumps. Dumps of overburden strata are recultivated - stable and artificially forested. This example of carrying out reclamation works of a part of the quarry and dump complex can be a model for the improvement of anthropogenically disturbed territories. Key words: granite quarries; geomorphological structure; excavated relief; heaped relief; Hnivan.

ORGANIZATIONAL AND TECHNOLOGICAL SOLUTIONS FOR THE REPAIR AND RESTORATION OF SEWAGE TUNNELS IN THE PLACES ADJACENT TO EXPLORATION MINES

The analysis of the occurrence of typical accidents of water drainage networks indicates a number of reasons for their failure, namely: a 2-3 times decrease in the amount of sewage over the last 20 years; increase in aggressiveness of wastewater, decrease in flow rate and increase in rainfall. During operation beyond the regulatory term, the reinforced concrete vault of the tunnel is almost completely destroyed as a result of biogenic corrosion. The listed reasons for the destruction of sewage tunnels built more than 50 years ago are generally similar in nature. From the above, it follows that the specifics of the operation of sewer tunnels can be highlighted - the cross-section diameter is more than 1500 mm and the laying depth is more than 5-7 m. It should be noted that the sections of the tunnels at the points of connection with inspection shafts, as well as the structure of inspection shafts, experience the greatest corrosion. A significant role in the repair and restoration of water drainage structures is played by the selection of materials and structures capable of counteracting the aggressive effects of hydrogen sulfide and other gases. In Ukraine and abroad, considerable experience has been accumulated in the repair and restoration of drainage network structures using materials and structures with high acid and alkali resistance. Conducted research has shown that products based on basalt have a number of advantages: high strength, fairly low weight, reliability during operation in a wide temperature range, they are not prone to corrosion and have high chemical resistance. The experience of working with pneumatic formwork gives them special importance, because they ensure the following requirements:quick installation and dismantling of the formwork; the possibility of using it for curved spatial surfaces forms, even with large spans;multiple reversibility of the formwork. The technology for the construction of the vaulted part of the sewer tunnel with internal finishing with stone casting tiles involves the following stages:dismantling of emergency sections of the tunnel (vaults, walls);clearing the tray part of the tunnel;restoration of the section of the tunnel part of the tunnel (if the tunnel is destroyed);cleaning of the existing fittings to ensure the joint operation of the tray and the protective coating of the vault being erected;installation of pneumatic formwork for the construction of the tunnel vault with internal finishing with stone casting tiles;laying stone casting tiles;installation of the necessary fittings for the protective lining of the vault made of monolithic reinforced concrete;creation of inventory formwork;laying the concrete mixture of the monolithic part of the vault;dismantling of pneumatic and inventory formwork after gaining strength of concrete;backfilling of the trench with compaction. The main period of restoration of the observation shaft with the help of lining the walls with stone-cast basalt tiles: dismantling of floor slabs; cleaning of walls from corrosion products; injection of anti-corrosion concrete on a small filler of space at the junctions of the tunnel; reinforcement of the mine walls (in case of deep corrosion of the walls); facing the walls of the observation shaft with stone-cast basalt tiles; treatment of the inner surface of operational areas and stairs with anti-corrosion epoxy polyurethane compound "AQUAKHIM". To justify the feasibility of using the proposed technology, two options for restoring the destroyed tunnel were considered: the method using stone casting tiles; the method of replacing destroyed pipes with polyethylene ones (an open method of restoration with dismantling of the destroyed tunnel). The option of restoring the sewer tunnel using stone casting tiles is almost 3 times more economical and expedient in terms of the cost of materials compared to the use of SPIRO PE pipe. The advantage of restoring sewage tunnels in this way is the durability and resistance of this material to aggressive effects, a sufficient amount of natural material in the country, and low cost. Keywords: sewage tunnel, inspection shaft, basalt, pneumatic formwork, technological solutions, open method.

Radio Link Model for Node Deployment in Underground Mine Sensor Networks

This paper presents an experimental characterization of the proposed radio link model for an underground mine sensor network. Power efficiency and range are critical factors to consider when designing a wireless sensor network, particularly for low data rate applications where the goal is to have a long-lasting, low-maintenance network. A ‘deploy and forget’ strategy is desirable because it allows the network to operate autonomously without requiring frequent maintenance or intervention from network operators. DASH7 and IEEE 802.15.4f are both excellent choices for low-power, long-range wireless sensor networking applications. The proposed radio link model was developed and evaluated for 433 MHz DASH7 in underground mines, considering the practical electromagnetic properties of mine walls and the propagation medium, which helps in calculating accurate signal characteristics. Radio wave propagation is a critical factor that needs to be considered when designing a wireless sensor network for complex mine structures. The received signal strength indicator (RSSI) and packet error rate (PER) are two key parameters that are used to measure wave propagation and assess the quality of the radio link between sensor nodes. The radio link design has been optimized for complex mine structures by utilizing these parameters in a model, leading to improved performance and reliability. The measurements were carried out in the world’s second largest salt mine at Khewra, Pakistan, with representative irregular mine structures. The RSSI and PER were measured at different node positions and with variable separation between the nodes. The proposed model allows for the easy placement of nodes on either the rooftop or near the side walls of the mine corridors, with an average variation of 6% in RSSI and 1.9% in PER. The proposed model was validated using off-the-shelf wizzi sensor nodes received from Wizzi Lab, France, and was programmed to measure RSSI and PER while operating under the 433 MHz DASH7 protocol. An agreement between modeled and measured parameters has been noted, making the proposed model a decent method for efficient node deployment in underground mine sensor networks.

A new mining method for reopening the opencast mine of Kef Essennoun

Purpose. To treat the stability problem of the phosphate Kef Essennoun quarry in the mining field of Jebel Onk located in the Northeastern part of Algeria. Methodology. To achieve these objectives, we started by monitoring the unstable area, using two monitoring systems: control stations and inclinometer. We then carried out a digital assessment of the Northwestern edge stability of the quarry under the current operating conditions of exploitation. After that, we proposed a new operating plan for the reopening of the depot under the required security conditions. At the end, we carried out an assessment of the edge stability, as the work to reopen and develop the Kef Essennoun quarry progressed. Findings. The results show that, under the current operating conditions of exploitation, the Northwestern edge of the Kef Essennoun quarry is unstable (FS < 1). The backfilling of the pilot pit of the mine, lead to the assurance of the mine walls stability, by increasing the values of safety factors with a rate of more than 30 %. Originality. The backfilling of the pilot pit of the mine and the resumption of top-down mining exploitation will ensure the stability of the quarry during and after the operating exploitation mining. Practical value. The study of the stability of the embankments bleachers, the edges of the quarries and the facings of the slag heaps during the open pit mining of useful ores deposits is an essential step that must be done gradually according to the development of mining works to guarantee the safety of personnel, materials, reserves and the environment.

A tunnel coaxial 3D hyperspectral scanning system for underground mine investigation

A hyperspectral scanning system was developed for three-dimensional (3D) surface mapping in underground spaces, such as mine shafts and tunnels. A hyperspectral line-scanning camera was mounted on the rotating driver unit coaxial with the tunnel to image both the mine wall and the ceiling. Uniform light was illuminated on the target surface to be imaged using a halogen lamp rotating together with the hyperspectral imaging sensor. Inertial Measuring Unit (IMU) was also attached to the sensor unit together with the hyperspectral camera so that sensor’s geometric information could be acquired simultaneously during imaging. All sensor and controller units were mounted on a cart-type platform for easy movement in the tunnel, and a battery mounted on the platform supplied power for system operation and the halogen light source. The developed scanning system was tested in an actual mine, and 3D hyperspectral images of the internal surface of the mine shaft were successfully obtained.

Instrumental monitoring for the location of endogenous fires in the coal mine wall

Introduction. Endogenous fire is a fire initiated by the process of self-ignition of coal. Detection of this type of fire is carried out visually by fire and smoke or by the results of temperature, gas or geophysical control. The occurrence of endogenous fires in coal mines leads to serious consequences, such as pollution of the environment and deterioration of sanitary and hygienic working conditions. It also leads to economic losses due to the suspension of technological processes and burnout of coal reserves. The prevention of endogenous fires includes measures to prevent the possible development of self-ignition processes in the identified areas of potential fire hazard. Research objective is to investigate areas of fire in active coal mines in order to determine the center of the profile of geophysical sounding, as close as possible to the epicenter of endogenous fire, to perform its binding to the mine plan and geological section. Methods of research. In order to achieve this goal, it is necessary to carry out a visual inspection of the areas of fire, to take photographs, as well as to carry out a thermal imaging survey with specialized equipment. Results. The results of photo- and thermal imaging surveys were recorded, the assessment of mining and geological conditions of formation of endogenous fires was carried out, and plans of the location of endogenous fires were presented. Conclusions and scope of results. After implementation of measures on inspection and survey in areas close to the centers of endogenous fires, as well as analysis of the results, we can conclude that direct visual inspections and thermal imaging measurements do not allow to fully determine the boundaries of fire zones in plan and depth. This is due to the fact that noticeable temperature anomalies are recorded only when the focus is directly on the ground surface due to the low thermal conductivity of coal and host rocks.

Mechanical Characteristics of Hybrid-Fiber-Reinforced Concrete Shaft Wall Structure Under Uneven Load

To prevent damage to shaft walls in mines due to uneven loading, the mechanical properties of a shaft wall structure made of hybrid-fiber-reinforced concrete were studied. First, through orthogonal testing, the optimal mix proportion of the hybrid-fiber-reinforced concrete was obtained. Subsequently, a numerical calculation model of the shaft wall structure under uneven loading was established. The calculation results showed that the structure exhibits a tensile stress under the action of uneven loading and that its bearing capacity can be improved using the hybrid-fiber-reinforced concrete. Based on the numerical simulation results, a calculation formula for the bearing capacity of the shaft wall was obtained by regression. Finally, a model test was conducted on the shaft lining structure. The results obtained were consistent with those obtained using the numerical simulation regression formula, confirming the reliability of the numerical simulation results. This study showed that a hybrid-fiber-reinforced concrete shaft wall structure can better withstand uneven loads and has improved brittle failure characteristics. Hybrid-fiber-reinforced concrete is an excellent material for deep shaft wall structures.

Wood use and forest management at the Late Bronze Age copper mining site of Prigglitz-Gasteil in the Eastern Alps – A combined anthracological, archaeological, and palynological approach

The Late Bronze Age mining site of Prigglitz-Gasteil provides a wealth of sources of information for the reconstruction of wood use, past vegetation, and forest management at a copper production facility. In this paper we have combined charcoal analyses from domestic and workshop contexts and the investigation of mining timbers found in the backfill of the opencast copper ore mine with the first results from pollen analyses from the nearby Saubachgraben mire. The complementary information from these different contexts allowed a reconstruction of the impact of settlement and mining activities on the natural mixed forest around the site, chiefly composed of beech, spruce, and fir. Forest clearing affected mainly spruce. Despite the dominance of spruce among the conifers, however, fir wood was exclusively selected for the production of mining timbers, which were used to support the opencast mine walls or for water management constructions. The gathering of firewood for domestic hearths followed the principle of least effort, leading to a secondary succession with pioneering species in the immediate surroundings of the mining settlement. The investigated wood and charcoal finds indicated an intentional and selective use of the locally available wood species. At the current state of the investigations, there is no evidence of scarcity or shortage in the wood supply.

Assembled design and compressive performance simulation of mine waterproof wall based on concrete 3D printing

With the increase of mining depth, the deep mine waterproof wall project faces the test of worse construction environment and higher risk of water damage. With the development of intelligent construction technology, it is necessary to introduce concrete 3D printing technology for the construction of coal mine waterproof walls, so as to adapt to more complex construction environment and engineering needs. Through uniaxial compression tests, the compressive properties of 3D printed concrete were tested under different printing methods and force directions. The results showed that the compressive strength of the 3D printed concrete was higher under the conditions of printing path B and loading along the direction parallel to the bonding layer. According to test results, the mine waterproof wall structure based on concrete 3D printing was designed. Then, ABAQUS was used to simulate the compressive strength and deformation of the 3D printed waterproof wall. The results showed that the ultimate load of the 3D printing module was 6.697e4kN and the deformation range was controllable, which meet the engineering requirements. The advantages of 3D printing mine waterproof walls are more flexible in design, faster in manufacturing, and more intelligent in operation. This work provides new ideas for the design and construction of waterproof walls in deep mines.

IOT Based Illegal Coal Mining Detection System

Abstract: When it comes to mining, there are two extremely crucial issues to consider:safety and legality. Illegal mining has been reported in numerous places of India. Combating this problem and ensuring that mining activity is carried out safely, as well as enhancing the effectiveness of discovering unlawful mining activities, is a serious task. At the moment, there is no effective way of detecting the presence of uncertainty in mines at an early stage, and as a result, people are dying. Natural disasters such as earthquakes, automobile collisions, and mine wall failures are all major risks. This project aids in the detection of unlawful mining in safe zones, hence preventing natural disasters. It also uses sensors to send values to the appropriate authorities when it detects any abnormal behavior .When the nodes thatforward the data are picked dynamically based on their battery life, energy efficiencyis practiced. The tool will also keep track of mining activities in remote areas.

The Role of Inertinite Characteristics and Coal Porosity of Seam A-1 of Muara Enim Formation in West Merapi, Lahat, South Sumatera, Indonesia

Coal contains a complex network of nano-, meso-, and a macro-pore can store fluids and allow fluids to flow through it. Nanoporosity in coal is primarily a result of molecules that have aromatic molecular structures and have been preserved in coal. Most adsorbate compounds, including gases, are stored here. The study area is located in South Sumatera, West Merapi Area, Lahat Regency. Geologically, the area in South Sumatra Basin belongs to the Middle-Late Miocene Muara Enim Formation. Using the ply-by-ply method, coal samples were taken directly from Seam-A in the coal mine walls outcrop, based on macroscopically determinable lithotype information. During laboratory analyses, coal is microscopically analyzed to determine the amount of porosity, permeability, and vitrinite reflectance. The purpose of this study is to investigate the change in composition and characteristics of inertinite macerals when the porosity value is varied.. Vitrinite content is between 91.00-92.80 %; liptinite 0.90-3.40%; inertinite 3.70-4.80%; mineral matter 0.7%-1.8%. Withh a vitrinite reflectance average of 0.34-0.36%, the variation in composition is an indication of changes in plant communities or coal facies. It is generally classified as sub-bituminous coal (ASTM). Porosity value of seam A upper is 1.9% and seam A lower 1.51%, permeability value seam A upper is 70.1 mD and seam A lower 27.1%. Composition of mineral matter in seam A upper is 0.8% and seam A lower 1.7%. The increasing number of inertinite pore is followed by lower porosity value. The inertinite maceral is predominantly aromatic with a high level of cross-linking, and exhibits a high level of aromatization and condensation. They have the highest carbon and the lowest oxygen hydrogen content. A coal maceral's porosity is composed of void spaces, such as open cell lumens preserved in semifusinite and sclerotinite. The porosity of cleats is the percentage of volume in relation to volume of coal, and the porosity of permeability. In coal, semifusinite has extensive interconnected pores that can form significant conduits for fluid flow.

Research on Factors Affecting Mine Wall Stability in Isolated Pillar Mining in Deep Mines

This study takes the Dongguashan Copper Mine as its engineering background. Based on the mechanical model of the mine wall under the trapezoidal load of the backfill, a comprehensive evaluation index is proposed, and its calculation equation is derived. On this basis, an orthogonal test is designed to explore the influence of mining design parameters on mine wall stability. The results show that the width of the mine wall is the main factor affecting its stability, and increasing the width of the mine wall can significantly improve its stability. When the width of the mine wall is kept above 4 m, its stability is better. When the mechanical parameters of the backfill are poor, the mine wall is prone to overturning failure. The width of the mine room has an influence on the multi-directional loading of the mine wall, but the influence on the stability of the mine wall is low. According to the regression equation calculation, the mine wall safety factor is about 1.46 under the design of G5 mining of Dongguashan Line 52, the stability of the mine wall is good after actual mining and the engineering application effect is ideal, which can provide a theoretical basis for the design of isolation pillar mining in deep mines.