Henan Pingdingshan No.10 mine is prone to both coal and gas outbursts.The E_(9-10)coal seam is the main coal-producing seam but has poor quality ventilation,thus making it relatively difficult for gas extraction.The F...Henan Pingdingshan No.10 mine is prone to both coal and gas outbursts.The E_(9-10)coal seam is the main coal-producing seam but has poor quality ventilation,thus making it relatively difficult for gas extraction.The F_(15)coal seam,at its lower section,is not prone to coal and gas outbursts.The average seam separation distance of 150 m is greater than the upper limit for underside protective seam mining.Based on borehole imaging technology for field exploration of coal and rock fracture characteristics and discrete element numerical simulation,we have studied the evolution laws and distribution characteristics of the coal and rock fissure field between these two coal seams.By analysis of the influential effect of group F coal mining on the E_(9-10)coal seam,we have shown that a number of small fissures also develop in the area some 150 m above the overlying strata.The width and number of the fissures also increase with the extent of mining activity.Most of the fissures develop at a low angle or even parallel to the strata.The results show that the mining of the F_(15)coal seam has the effect of improving the permeability of the E_(9-10)coal seam.展开更多
Based on characteristic of the associated mining of multi-coal seam and the engineering geological characteristics of overburden,the mining impact pattern of multi- seam mining and the dynamic fracture mechanism of ov...Based on characteristic of the associated mining of multi-coal seam and the engineering geological characteristics of overburden,the mining impact pattern of multi- seam mining and the dynamic fracture mechanism of overburden were characterized by applying the engineering geological mechanical model test.The related strata movement parameters and influence area of multi-seam mining were obtained,the strike boundary angle is 61°,the full extraction coefficient is 0.93,the greatest subsidence angle is 81°,the horizontal movement factor is 0.38,the deviation of inflection point/mining deep is 0.11. The development height of caving zone and water flowing fractured zone of multi-seam mining were calculated,is 32 m and 81.5 m separatly.The assess of influence degree of coal layer safety mining is that,there exists the possibility of water and sand inflow when mining,some messures for mine water prevention and control should be used,and the mining thickness should be local strictly limit.展开更多
In order to ensure safe mining and reduce surface damage in shallow multi-seam mining,the failure characteristics of interburden strata with different coal pillars offset distances between pillars in the upper and low...In order to ensure safe mining and reduce surface damage in shallow multi-seam mining,the failure characteristics of interburden strata with different coal pillars offset distances between pillars in the upper and lower seams,the distribution characteristics of stress concentration in coal pillars,and the development characteristics of stratum cracks and subsidence were investigated by physical and UDEC2D simulation.Meanwhile,the effect of different coal pillar offset distances on stress concentration of coal pillar and development of stratum cracks were studied.Based on those results,a formula for safe mining and reducing surface damage was established,which provided a theoretical basis for safe and environmentally friendly mining in shallow multi-seam.According to the results,the optimal coal pillar offset distance(the side to side horizontal distance of the upper and lower coal pillars)between the upper and lower coal seams was developed to reduce the stress concentration of coal pillars and surface damage.The results of this study have been applied in Ningtiaota coal mine and have achieved good results in safe and environmentally friendly mining.展开更多
Mine surveying is an indispensable and crucial basic technical work in the process of mineral resource development.It plays an important role throughout the entire life cycle of a mine,from exploration,design,construc...Mine surveying is an indispensable and crucial basic technical work in the process of mineral resource development.It plays an important role throughout the entire life cycle of a mine,from exploration,design,construction,and production to closure,and is known as the“eyes of the mine”.With the rapid development of satellite technology,computer science,artificial intelligence,robotics,and spatiotemporal big data,mine surveying science and technology supported by spatial information technology is increasingly playing the role of the“brain of the mine”.This paper systematically summarizes the characteristics of mining surveying science and technology in contemporary and future mining development.First,based on the requirements of safe,efficient,and green development in modern mining,an analysis is conducted on the innovative practices of intelligent mining methods;secondly,it explains the transformation of regional economic and mining economic integration towards lengthening the industrial chain and scientific and technological innovation.Regarding intelligent mining,this paper discusses three technical dimensions:(1)By establishing a spatiotemporal data model of the mine,real-time perception and remote intelligent control of the production system are realized;(2)Based on the transparent mine three-dimensional geological modelling technology,the accuracy of geological condition prediction and the scientific nature of mining decisions are significantly improved;(3)By integrating multi-source remote sensing data and deep learning algorithms,a high-precision coal and rock identification system is constructed.The study further revealed the innovative application value of mine surveying in the post-mining era,including:diversified utilization of underground space in mining areas(tourism development,geothermal energy storage,pumped storage,etc.),multi-platform remote sensing coordinated ecological restoration monitoring,and optimized land space planning in mining areas.Practice has proved that mine surveying technology is an important technical engine for promoting green transformation and high-quality development in resource-based regions,and has irreplaceable strategic significance for achieving coordinated development of energy,economy,and environment.展开更多
Processes supported by process-aware information systems are subject to continuous and often subtle changes due to evolving operational,organizational,or regulatory factors.These changes,referred to as incremental con...Processes supported by process-aware information systems are subject to continuous and often subtle changes due to evolving operational,organizational,or regulatory factors.These changes,referred to as incremental concept drift,gradually alter the behavior or structure of processes,making their detection and localization a challenging task.Traditional process mining techniques frequently assume process stationarity and are limited in their ability to detect such drift,particularly from a control-flow perspective.The objective of this research is to develop an interpretable and robust framework capable of detecting and localizing incremental concept drift in event logs,with a specific emphasis on the structural evolution of control-flow semantics in processes.We propose DriftXMiner,a control-flow-aware hybrid framework that combines statistical,machine learning,and process model analysis techniques.The approach comprises three key components:(1)Cumulative Drift Scanner that tracks directional statistical deviations to detect early drift signals;(2)a Temporal Clustering and Drift-Aware Forest Ensemble(DAFE)to capture distributional and classification-level changes in process behavior;and(3)Petri net-based process model reconstruction,which enables the precise localization of structural drift using transition deviation metrics and replay fitness scores.Experimental validation on the BPI Challenge 2017 event log demonstrates that DriftXMiner effectively identifies and localizes gradual and incremental process drift over time.The framework achieves a detection accuracy of 92.5%,a localization precision of 90.3%,and an F1-score of 0.91,outperforming competitive baselines such as CUSUM+Histograms and ADWIN+Alpha Miner.Visual analyses further confirm that identified drift points align with transitions in control-flow models and behavioral cluster structures.DriftXMiner offers a novel and interpretable solution for incremental concept drift detection and localization in dynamic,process-aware systems.By integrating statistical signal accumulation,temporal behavior profiling,and structural process mining,the framework enables finegrained drift explanation and supports adaptive process intelligence in evolving environments.Its modular architecture supports extension to streaming data and real-time monitoring contexts.展开更多
Mineral resources in Asia continent and its mining industry play a significant role in the economic growth and industrialization of both Asia and the world.Asia continent boasts the most comprehensive kinds of mineral...Mineral resources in Asia continent and its mining industry play a significant role in the economic growth and industrialization of both Asia and the world.Asia continent boasts the most comprehensive kinds of minerals,with reserves of at least 38 of over 80 widely used minerals worldwide accounting for more than30%of the global total reserves.Asia continent experienced three main tectonic evolution and mineralization stages:The Precambrian,the Paleozoic,and the Mesozoic to Cenozoic.The abundant mineral resources in this continent can be divided into seven first-order metallogenic belts(metallogenic domains),18 second-order metallogenic belts(metallogenic provinces),61 third-order metallogenic belts(metallogenic zones),and nine main minerogenetic series.Asia continent exhibits the most significant metallogenic specialization among all continents.Specifically,granite belts of Asia continent manifest pronounced metallogenic specialization of tin,rare metals,and porphyry Cu-Au-Mo deposits.Its maficultramafic rock belts and ophiolite belts display notable metallogenic specialization of lateritic nickel deposits and magmatic type chromite deposits,while its Mesozoic to Cenozoic basalt belts show remarkable metallogenic specialization of lateritic bauxite deposits.Consequently,many giant metallogenic belts were formed,including the Southeast Asian tin belt,the Qinghai-Xizang Plateau rare metal metallogenic belt,the Tethyan porphyry Cu-Au-Mo metallogenic belt,the circum-Pacific porphyry Cu-Au-Mo metallogenic belt,the Southeast Asian lateritic bauxite metallogenic belt,the Deccan Plateau lateritic bauxite metallogenic belt in India,the Southeast Asian lateritic nickel metallogenic belt,and the Tethyan magmatic type chromite metallogenic belt—all of which are significant metallogenic belts in Asia continent.Future mineral exploration in Asia should focus primarily on the Precambrian mineralization of ancient cratons,the Paleozoic mineralization of the Central Asian-Mongolian orogenic belt,and the Mesozoic to Cenozoic mineralization of the Tethyan and circum-Pacific mobile belts.Asia's mining industry not only underpins its own economic growth but also propels global economic development and industrialization,contributing significantly to the world economy.Asia boasts the highest production value of minerals,the largest annual production of minerals,and the greatest trade value of mineral products among all the continents,having emerged as the trade center of global mineral products and the center of the mining industry economy.China is identified as one of the few countries that possess the most comprehensive kinds of minerals,and its mining industry has supported and driven the economic development and industrialization of Asia and even the world.Standing as the largest mineral producer worldwide,China ranked first in the production of 28 mineral commodities in the world in 2022.Besides,China exhibits the highest annual production value of minerals and the largest trade value of mineral products among all countries.Therefore,China's demand for global mineral products influences the global supply and demand patterns of minerals and the world economic situation.展开更多
Enhancing the mining speed of a working face has become the primary approach to achieve high production and efficiency in coal mines,thereby further improving the production capacity.However,the problem of rock bursts...Enhancing the mining speed of a working face has become the primary approach to achieve high production and efficiency in coal mines,thereby further improving the production capacity.However,the problem of rock bursts resulting from this approach has become increasingly serious.Therefore,to implement coal mine safety and efficient extraction,the impact of deformation pressure caused by different mining speeds should be considered,and a reasonable mining speed of the working face should be determined.The influence of mining speed on overlying rock breaking in the stope is analyzed by establishing a key layer block rotation and subsidence model.Results show that with the increasing mining speed,the compression amount of gangue in the goaf decreases,and the rotation and subsidence amount of rock block B above goaf decreases,forcing the rotation and subsidence amount of rock block A above roadway to increase.Consequently,the contact mode between rock block A and rock block B changes from line contact to point contact,and the horizontal thrust and shear force between blocks increase.The increase in rotation and subsidence of rock block A intensifies the compression degree of coal and rock mass below the key layer,thereby increasing the stress concentration degree of coal and rock mass as well as the total energy accumulation.In addition,due to the insufficient compression of gangue in the goaf,the bending and subsidence space of the far-field key layer are limited,the length of the suspended roof increases,and the influence range of mining stress and the energy accumulation range expand.Numerical test results and underground microseismic monitoring results verify the correlation between mining speed and stope energy,and high-energy events generally appear 1-2 d after the change in mining speed.On this basis,the statistical principle confirms that the maximum mining speed of the working face at 6 m/d is reasonable.展开更多
In the context of increasing demand for coal mine resources in China’s current socio-economic development,traditional mining methods have been difficult to effectively meet the requirements of safety production and e...In the context of increasing demand for coal mine resources in China’s current socio-economic development,traditional mining methods have been difficult to effectively meet the requirements of safety production and environmental protection.As a result,coal mine filling mining technology has emerged,which can effectively achieve the goal of controlling surface subsidence in practical applications,while also significantly improving the recovery rate of coal resources.Based on this,this study will first elaborate on the characteristics of filling mining technology,and then analyze the key points of the application of supporting technology for mechanical and electrical equipment in the corresponding working face based on actual cases,in order to provide support for improving the efficiency of coal mining.展开更多
Coal mine underground reservoir(CMUR) technology mitigates water scarcity in China's coal-rich western regions but lacks tailored solutions for steeply inclined coal seams.This study develops a novel framework of ...Coal mine underground reservoir(CMUR) technology mitigates water scarcity in China's coal-rich western regions but lacks tailored solutions for steeply inclined coal seams.This study develops a novel framework of steeply inclined coal mine underground reservoirs(SICMUR),which is a paradigm shift from conventional CMUR that the coal seam itself serves as the reservoir floor,challenging conventional designs due to depth-dependent permeability and mechanical constraints.Triaxial mechanical-seepage tests on Xinjiang Wudong coal samples(100,200,300 m depths) revealed a 3.5 MPa triaxial strength increase per 100 m depth and a 58-fold post-peak permeability surge at 300 versus 100 m.Similar model simulations revealed mining-induced stress redistribution and significant deformation effects,particularly subsidence and water-conducting fractures during lower coal seam mining.Results indicate a minimum 40 m safety distance between reservoirs and lower coal seams.Critical construction parameters were investigated for Wudong mine SICMUR as collapse zone heights(9.9–12.31 m) and waterconducting fracture zone heights(31.96–37.40 m).This work systematically bridges SICMUR concepts to field implementation,offering a framework for water preservation in steeply inclined mining while addressing safety concerns,providing a new approach for water reservation in steeply inclined coal mining.展开更多
39 soil samples surrounding a lead-zinc mining area in Guangxi were collected,and the contents of Pb,Hg,Cd,Cr,As,Cu,Zn,and Ni were determined to investigate the pollution characteristics and sources of heavy metals.Ar...39 soil samples surrounding a lead-zinc mining area in Guangxi were collected,and the contents of Pb,Hg,Cd,Cr,As,Cu,Zn,and Ni were determined to investigate the pollution characteristics and sources of heavy metals.ArcGIS inverse distance weight difference method was used to analyze the characteristics of pollution distribution,and single-factor pollution index,Nemerow comprehensive pollution index,ground accumulation index,and potential ecological risk index were selected to evaluate the characteristics of heavy metal pollution.Based on correlation analysis,the absolute principal component-multiple linear regression(APCS-MLR)and positive definite matrix factorization(PMF)models were used to analyze the sources of soil heavy metals.The results showed that the average concentrations of all eight heavy metals exceeded both national and Guangxi soil background values.Hg,Cd,and Zn exhibited high variation(greater than 0.5),indicating significant external disturbances,and their spatial distribution was closely related to mining activity locations.The single-factor pollution index evaluation indicated varying degrees of pollution risk for Cd,Zn,and As,with Cd and Zn being the most severe pollutants,as 69.23%and 30.77%of the samples fell into the moderate pollution or higher category.The geoaccumulation index analysis ranked the mean pollution levels of the eight elements as follows:Zn>Cd>Ni>Pb>Cu>Cr>Hg>As,with Cd and Zn showing the most severe contamination,and 51.28%of the samples exhibiting moderate or higher pollution levels.The Nemerow comprehensive pollution index evaluation showed that 74.35%of soil samples were classified as moderate to heavy pollution.The potential ecological risk index assessment indicated significant ecological risks posed by Cd and Zn,with 82.05%and 5.12%of the samples classified as causing strong to extreme ecological risks,respectively.The source apportionment analysis revealed minor differences between the two models.The APCS-MLR model identified three pollution sources and their contribution rates:anthropogenic mining sources(31.13%),parent material sources(40.38%),and unidentified sources(28.49%).The PMF model identified three pollution sources with contribution rates of anthropogenic mining sources(26.10%),parent material sources(46.96%),and a combined traffic and agricultural source(26.61%).Pb,Hg,Cd,and Zn mainly originated from mining activities;Cr,As,and Ni were primarily derived from the parent material,while Cu was predominantly attributed to traffic and agricultural sources.These findings provide a scientific basis for the prevention and control of heavy metal pollution in mining areas.展开更多
Stability of base-exposed backfill roof in underhand drift-and-fill mining is crucial for the safety of those working beneath.Given the commonly used primary-and-secondary mining sequence,interfaces are formed between...Stability of base-exposed backfill roof in underhand drift-and-fill mining is crucial for the safety of those working beneath.Given the commonly used primary-and-secondary mining sequence,interfaces are formed between adjacent filled drifts,which can weaken the integrity of the backfill roof.These interfaces also lead to two common drift layouts:aligned drifts and staggered drifts.However,less attention has been paid to the interfaces and the two drift layouts were not adequately distinguished in previous studies.In this paper,the interfaces between filled drifts were firstly considered to investigate the stability of backfill roof.Failure modes and strength requirements of backfill roof in aligned and staggered drifts are comprehensively investigated by FLAC3D,with a focus on considerations of varied shear parameters of the interfaces.Results show that failure modes in aligned drifts transition from block sliding to top caving,bottom caving or sloughing as the interface cohesion increases from zero to at least half of the backfill cohesion.Further increases in interface cohesion allow aligned drifts to behave as if there are no interfaces between them.The critical stability conditions of backfill roof in aligned drifts were mostly determined by the interface strength instead of the backfill strength.However,the stability of backfill roof in staggered drifts is barely affected by the interface strength.The outcomes are expected to provide references for mining engineers to optimize drift layouts and perform cost-effective backfill roof strength design at mines using underhand drift-and-fill mining method.展开更多
Deep karst fractures significantly drive rock strata movement induced by mining and are one of the key factors causing slope failures.Understanding the disaster formation mechanisms of mining-induced slopes controlled...Deep karst fractures significantly drive rock strata movement induced by mining and are one of the key factors causing slope failures.Understanding the disaster formation mechanisms of mining-induced slopes controlled by deep karst fractures is crucial for geological hazard prevention and mitigation.Existing research on slope failure mechanisms under the coupled influence of deep karst fractures and underground coal mining remains limited and insufficiently developed.Consequently,this study establishes a coupled geomechanical model of mining-karst interaction for layered reverse-dip slopes in southwestern China.By integrating field investigations with discrete element simulations,this study explores the deformation characteristics and failure mechanisms of deeply fractured karst slopes subjected to underground mining,along with their impacts on slope stability.The main findings are as follows:(1)Deep rock karst fractures dominated the spatial distribution of tensile fracture zones,forming a dynamic stress arch effect above the goaf;(2)The mining process dynamically induced a three-stage destruction mode of the slope,namely,the bending effect caused by the dynamic stress arch,arch migration,and the evolution of the unlocking of the locking rocks;(3)Significant spatiotemporal variability existed between the tensile zone at the top of the slope and the shear zone on the slope surface,leading to the gradual overturning of the cantilever beam structure along the dominant structural surface.It indicates that deep rock karst fractures are the primary factor controlling the disaster of the cantilever beam structure,exacerbating the degree of rock fracture and surface subsidence induced by coal mining.This study reveals the chain disaster mechanism of layered anti-dip rock karst fracture slopes in southwestern China,namely,fracture penetration,rock stratum movement-induced failure,unlocking of key rocks,and final tensile overturning destruction,profoundly elucidating the critical role of rock dissolution fissures in mining-induced slope disasters.展开更多
Comprehending the flow behavior of deep-sea mining plumes is paramount for precise predictions of their propagation range and holds immense significance in advancing the commercial exploitation of deep-sea minerals.As...Comprehending the flow behavior of deep-sea mining plumes is paramount for precise predictions of their propagation range and holds immense significance in advancing the commercial exploitation of deep-sea minerals.As deep-sea mining plumes propagate,they can transition from high-density non-Newtonian fluids to low-density Newtonian fluids.However,a comprehensive rheological model capable of accurately describing this intricate evolutionary process is currently lacking.This study explores the variations in rheological properties observed during the propagation of deep-sea mining plumes,utilizing rheological test data obtained from kaolin clay plumes.Utilizing the Power Law model,we established a power exponential function correlating the plume rheological parameters(consistency index and flow behavior index)with a density range from 1.00 to 1.50 g/cm3 through data fitting,developing a rheological model of deep-sea mining plumes considering the variations in plume density.Subsequently,taking into account the differences in sediment properties,the effects of clay content and clay mineral composition on the rheological parameters of natural sediment plumes were compared and analyzed.This model provides a reference for understanding the rheological properties of deep-sea mining plumes during their propagation.展开更多
The failure and collapse of coal pillar ribs represent a significant hazard in the mining industry,with the associated risk of fatalities and injuries anticipated to rise as mining operations advance to greater depths...The failure and collapse of coal pillar ribs represent a significant hazard in the mining industry,with the associated risk of fatalities and injuries anticipated to rise as mining operations advance to greater depths.The development of support guidelines through an enhanced understanding of pillar damage and rock–support interaction mechanisms is crucial to resolving this issue.Bonded block models(BBMs)represent a convenient tool for this purpose,as they can reasonably reproduce the rock fracturing process;however,it is not known to what extent this modeling technique can be applied to simulate pillar failure mechanisms and support interaction in anisotropic rock masses,such as coal.To bridge this gap in research,hypothetical coal pillar BBMs of different width-to-height ratios were developed and calibrated to match Mark–Bieniawski's pillar strength equation,along with a few other attributes from the literature(stress levels at the edge of pillars and the transition from brittle to strain-hardening behavior with increasing width-to-height ratio).Elongated blocks were employed to capture the anisotropic behavior of coal mass.With the reliability of the model established,a few different support patterns were evaluated to ensure that the outputs are broadly consistent with expectations.Finally,simulations of roadway development and additional mining activities were completed considering geo-mining conditions representative of underground coal mines in the USA.The good consistency between model response and expected behaviors per field observation demonstrates the potential of BBMs to be used as a support design tool.展开更多
The sublevel top coal caving(SLTCC)mining is widely employed in steeply inclined and thick coal seams.In SLTCC,the large coal drawing height and the influence of roof and floor boundaries introduce significant complex...The sublevel top coal caving(SLTCC)mining is widely employed in steeply inclined and thick coal seams.In SLTCC,the large coal drawing height and the influence of roof and floor boundaries introduce significant complexity into the coal extraction process.The study demonstrates that,in an SLTCC working face,the granular nature of top coal gives rise to a'locking-embedding'effect and a'loosening-compaction'cycle during the drawing process.These phenomena invalidate several core assumptions of the conventional Bergmark-Roos(B-R)model,which is no longer fully established,and the maximum moving angle changes dynamically.Therefore,an improved B-R model was proposed to account for the dynamic variations in particle shape and maximum transport angle,and the corresponding boundary equations of the drawing body were derived.Additionally,a novel numerical simulation method based on the rolling resistance linear model(RRLM),which takes into account particle shape,has been introduced.Validation was conducted through numerical simulations and physical experiments.Both numerical and physical tests confirmed that the improved B-R model more accurately captures the drawing body shape in SLTCC.Field measurement data in Wudong coal mine in Xinjiang,China,further substantiated the model's validity.In addition,as sublevel height increases,the drawing body exhibits markedly different evolution trends on the roof-and floor-side boundaries.Formulas for the improved B-R model at various sublevel heights were established.The research may provide new approaches for SLTCC simulations and theoretical calculations of drawing body shape at different sublevel heights.展开更多
Xinli district of Sanshandao Gold Mine is the first subsea metal mine in China.To achieve 6 kt/d production capacity under the premise of safe mining,high-intensity mining might destroy the in-situ stress filed and th...Xinli district of Sanshandao Gold Mine is the first subsea metal mine in China.To achieve 6 kt/d production capacity under the premise of safe mining,high-intensity mining might destroy the in-situ stress filed and the stability of rockmass.According to sampling and testing of ore-rock and backfill and in-situ stress field measurement,safety factor method calculation model based on stress-strain strength reduction at arbitrary points and Mohr-Coulomb yield criterion was established and limit displacement subsidence values under the safety factor of different limit stoping steps were calculated.The results from three years in-situ mining and strata movement monitoring using multi-point displacements meter showed that the lower settlement frame stope hierarchical level filling mining method,mining sequence are reasonable and rockmass stability evaluation using safety factor method,in-situ real-time monitoring can provide the technical foundation for the safety of seabed mining.展开更多
基金financially supported by the State Key Basic Research Program of China(No.2011CB201203)the State Key Special Program of China(No.2011ZX05040-001-005)the National Natural Science Foundation of China(No.51374256)
文摘Henan Pingdingshan No.10 mine is prone to both coal and gas outbursts.The E_(9-10)coal seam is the main coal-producing seam but has poor quality ventilation,thus making it relatively difficult for gas extraction.The F_(15)coal seam,at its lower section,is not prone to coal and gas outbursts.The average seam separation distance of 150 m is greater than the upper limit for underside protective seam mining.Based on borehole imaging technology for field exploration of coal and rock fracture characteristics and discrete element numerical simulation,we have studied the evolution laws and distribution characteristics of the coal and rock fissure field between these two coal seams.By analysis of the influential effect of group F coal mining on the E_(9-10)coal seam,we have shown that a number of small fissures also develop in the area some 150 m above the overlying strata.The width and number of the fissures also increase with the extent of mining activity.Most of the fissures develop at a low angle or even parallel to the strata.The results show that the mining of the F_(15)coal seam has the effect of improving the permeability of the E_(9-10)coal seam.
基金the National Natural Science Foundation of China(40372123)
文摘Based on characteristic of the associated mining of multi-coal seam and the engineering geological characteristics of overburden,the mining impact pattern of multi- seam mining and the dynamic fracture mechanism of overburden were characterized by applying the engineering geological mechanical model test.The related strata movement parameters and influence area of multi-seam mining were obtained,the strike boundary angle is 61°,the full extraction coefficient is 0.93,the greatest subsidence angle is 81°,the horizontal movement factor is 0.38,the deviation of inflection point/mining deep is 0.11. The development height of caving zone and water flowing fractured zone of multi-seam mining were calculated,is 32 m and 81.5 m separatly.The assess of influence degree of coal layer safety mining is that,there exists the possibility of water and sand inflow when mining,some messures for mine water prevention and control should be used,and the mining thickness should be local strictly limit.
基金The article was funded by the National Natural Science Foundation of China(Nos.51674190 and 52074211)the Natural Science Basic Research Program of Shaanxi(Nos.2019JQ-798 and 2019JLP-08).The authors also thank the reviewers for their patient work.
文摘In order to ensure safe mining and reduce surface damage in shallow multi-seam mining,the failure characteristics of interburden strata with different coal pillars offset distances between pillars in the upper and lower seams,the distribution characteristics of stress concentration in coal pillars,and the development characteristics of stratum cracks and subsidence were investigated by physical and UDEC2D simulation.Meanwhile,the effect of different coal pillar offset distances on stress concentration of coal pillar and development of stratum cracks were studied.Based on those results,a formula for safe mining and reducing surface damage was established,which provided a theoretical basis for safe and environmentally friendly mining in shallow multi-seam.According to the results,the optimal coal pillar offset distance(the side to side horizontal distance of the upper and lower coal pillars)between the upper and lower coal seams was developed to reduce the stress concentration of coal pillars and surface damage.The results of this study have been applied in Ningtiaota coal mine and have achieved good results in safe and environmentally friendly mining.
基金supported by the National Natural Science Foundation of China(Nos.52394193 and U22A20569)the National Key R&D Program Projects(Nos.2023YFC3804200 and 2023YFC3804205).
文摘Mine surveying is an indispensable and crucial basic technical work in the process of mineral resource development.It plays an important role throughout the entire life cycle of a mine,from exploration,design,construction,and production to closure,and is known as the“eyes of the mine”.With the rapid development of satellite technology,computer science,artificial intelligence,robotics,and spatiotemporal big data,mine surveying science and technology supported by spatial information technology is increasingly playing the role of the“brain of the mine”.This paper systematically summarizes the characteristics of mining surveying science and technology in contemporary and future mining development.First,based on the requirements of safe,efficient,and green development in modern mining,an analysis is conducted on the innovative practices of intelligent mining methods;secondly,it explains the transformation of regional economic and mining economic integration towards lengthening the industrial chain and scientific and technological innovation.Regarding intelligent mining,this paper discusses three technical dimensions:(1)By establishing a spatiotemporal data model of the mine,real-time perception and remote intelligent control of the production system are realized;(2)Based on the transparent mine three-dimensional geological modelling technology,the accuracy of geological condition prediction and the scientific nature of mining decisions are significantly improved;(3)By integrating multi-source remote sensing data and deep learning algorithms,a high-precision coal and rock identification system is constructed.The study further revealed the innovative application value of mine surveying in the post-mining era,including:diversified utilization of underground space in mining areas(tourism development,geothermal energy storage,pumped storage,etc.),multi-platform remote sensing coordinated ecological restoration monitoring,and optimized land space planning in mining areas.Practice has proved that mine surveying technology is an important technical engine for promoting green transformation and high-quality development in resource-based regions,and has irreplaceable strategic significance for achieving coordinated development of energy,economy,and environment.
文摘Processes supported by process-aware information systems are subject to continuous and often subtle changes due to evolving operational,organizational,or regulatory factors.These changes,referred to as incremental concept drift,gradually alter the behavior or structure of processes,making their detection and localization a challenging task.Traditional process mining techniques frequently assume process stationarity and are limited in their ability to detect such drift,particularly from a control-flow perspective.The objective of this research is to develop an interpretable and robust framework capable of detecting and localizing incremental concept drift in event logs,with a specific emphasis on the structural evolution of control-flow semantics in processes.We propose DriftXMiner,a control-flow-aware hybrid framework that combines statistical,machine learning,and process model analysis techniques.The approach comprises three key components:(1)Cumulative Drift Scanner that tracks directional statistical deviations to detect early drift signals;(2)a Temporal Clustering and Drift-Aware Forest Ensemble(DAFE)to capture distributional and classification-level changes in process behavior;and(3)Petri net-based process model reconstruction,which enables the precise localization of structural drift using transition deviation metrics and replay fitness scores.Experimental validation on the BPI Challenge 2017 event log demonstrates that DriftXMiner effectively identifies and localizes gradual and incremental process drift over time.The framework achieves a detection accuracy of 92.5%,a localization precision of 90.3%,and an F1-score of 0.91,outperforming competitive baselines such as CUSUM+Histograms and ADWIN+Alpha Miner.Visual analyses further confirm that identified drift points align with transitions in control-flow models and behavioral cluster structures.DriftXMiner offers a novel and interpretable solution for incremental concept drift detection and localization in dynamic,process-aware systems.By integrating statistical signal accumulation,temporal behavior profiling,and structural process mining,the framework enables finegrained drift explanation and supports adaptive process intelligence in evolving environments.Its modular architecture supports extension to streaming data and real-time monitoring contexts.
基金funded by geological survey project of China Geological Survey(DD20211404)。
文摘Mineral resources in Asia continent and its mining industry play a significant role in the economic growth and industrialization of both Asia and the world.Asia continent boasts the most comprehensive kinds of minerals,with reserves of at least 38 of over 80 widely used minerals worldwide accounting for more than30%of the global total reserves.Asia continent experienced three main tectonic evolution and mineralization stages:The Precambrian,the Paleozoic,and the Mesozoic to Cenozoic.The abundant mineral resources in this continent can be divided into seven first-order metallogenic belts(metallogenic domains),18 second-order metallogenic belts(metallogenic provinces),61 third-order metallogenic belts(metallogenic zones),and nine main minerogenetic series.Asia continent exhibits the most significant metallogenic specialization among all continents.Specifically,granite belts of Asia continent manifest pronounced metallogenic specialization of tin,rare metals,and porphyry Cu-Au-Mo deposits.Its maficultramafic rock belts and ophiolite belts display notable metallogenic specialization of lateritic nickel deposits and magmatic type chromite deposits,while its Mesozoic to Cenozoic basalt belts show remarkable metallogenic specialization of lateritic bauxite deposits.Consequently,many giant metallogenic belts were formed,including the Southeast Asian tin belt,the Qinghai-Xizang Plateau rare metal metallogenic belt,the Tethyan porphyry Cu-Au-Mo metallogenic belt,the circum-Pacific porphyry Cu-Au-Mo metallogenic belt,the Southeast Asian lateritic bauxite metallogenic belt,the Deccan Plateau lateritic bauxite metallogenic belt in India,the Southeast Asian lateritic nickel metallogenic belt,and the Tethyan magmatic type chromite metallogenic belt—all of which are significant metallogenic belts in Asia continent.Future mineral exploration in Asia should focus primarily on the Precambrian mineralization of ancient cratons,the Paleozoic mineralization of the Central Asian-Mongolian orogenic belt,and the Mesozoic to Cenozoic mineralization of the Tethyan and circum-Pacific mobile belts.Asia's mining industry not only underpins its own economic growth but also propels global economic development and industrialization,contributing significantly to the world economy.Asia boasts the highest production value of minerals,the largest annual production of minerals,and the greatest trade value of mineral products among all the continents,having emerged as the trade center of global mineral products and the center of the mining industry economy.China is identified as one of the few countries that possess the most comprehensive kinds of minerals,and its mining industry has supported and driven the economic development and industrialization of Asia and even the world.Standing as the largest mineral producer worldwide,China ranked first in the production of 28 mineral commodities in the world in 2022.Besides,China exhibits the highest annual production value of minerals and the largest trade value of mineral products among all countries.Therefore,China's demand for global mineral products influences the global supply and demand patterns of minerals and the world economic situation.
基金supported by Technology Innovation Fund of China Coal Research Institute(2022CX-I-04)Science and Technology Innovation Venture Capital Project of China Coal Technology Engineering Group(2020-2-TD-CXY005)。
文摘Enhancing the mining speed of a working face has become the primary approach to achieve high production and efficiency in coal mines,thereby further improving the production capacity.However,the problem of rock bursts resulting from this approach has become increasingly serious.Therefore,to implement coal mine safety and efficient extraction,the impact of deformation pressure caused by different mining speeds should be considered,and a reasonable mining speed of the working face should be determined.The influence of mining speed on overlying rock breaking in the stope is analyzed by establishing a key layer block rotation and subsidence model.Results show that with the increasing mining speed,the compression amount of gangue in the goaf decreases,and the rotation and subsidence amount of rock block B above goaf decreases,forcing the rotation and subsidence amount of rock block A above roadway to increase.Consequently,the contact mode between rock block A and rock block B changes from line contact to point contact,and the horizontal thrust and shear force between blocks increase.The increase in rotation and subsidence of rock block A intensifies the compression degree of coal and rock mass below the key layer,thereby increasing the stress concentration degree of coal and rock mass as well as the total energy accumulation.In addition,due to the insufficient compression of gangue in the goaf,the bending and subsidence space of the far-field key layer are limited,the length of the suspended roof increases,and the influence range of mining stress and the energy accumulation range expand.Numerical test results and underground microseismic monitoring results verify the correlation between mining speed and stope energy,and high-energy events generally appear 1-2 d after the change in mining speed.On this basis,the statistical principle confirms that the maximum mining speed of the working face at 6 m/d is reasonable.
文摘In the context of increasing demand for coal mine resources in China’s current socio-economic development,traditional mining methods have been difficult to effectively meet the requirements of safety production and environmental protection.As a result,coal mine filling mining technology has emerged,which can effectively achieve the goal of controlling surface subsidence in practical applications,while also significantly improving the recovery rate of coal resources.Based on this,this study will first elaborate on the characteristics of filling mining technology,and then analyze the key points of the application of supporting technology for mechanical and electrical equipment in the corresponding working face based on actual cases,in order to provide support for improving the efficiency of coal mining.
基金supported by Beijing Natural Science Foundation (No.8254049)the National Natural Science Foundation of China (No.52374139)the Deep Earth Probe and Mineral Resources Exploration-National Science and Technology Major Project (No.2024ZD1004505)。
文摘Coal mine underground reservoir(CMUR) technology mitigates water scarcity in China's coal-rich western regions but lacks tailored solutions for steeply inclined coal seams.This study develops a novel framework of steeply inclined coal mine underground reservoirs(SICMUR),which is a paradigm shift from conventional CMUR that the coal seam itself serves as the reservoir floor,challenging conventional designs due to depth-dependent permeability and mechanical constraints.Triaxial mechanical-seepage tests on Xinjiang Wudong coal samples(100,200,300 m depths) revealed a 3.5 MPa triaxial strength increase per 100 m depth and a 58-fold post-peak permeability surge at 300 versus 100 m.Similar model simulations revealed mining-induced stress redistribution and significant deformation effects,particularly subsidence and water-conducting fractures during lower coal seam mining.Results indicate a minimum 40 m safety distance between reservoirs and lower coal seams.Critical construction parameters were investigated for Wudong mine SICMUR as collapse zone heights(9.9–12.31 m) and waterconducting fracture zone heights(31.96–37.40 m).This work systematically bridges SICMUR concepts to field implementation,offering a framework for water preservation in steeply inclined mining while addressing safety concerns,providing a new approach for water reservation in steeply inclined coal mining.
文摘39 soil samples surrounding a lead-zinc mining area in Guangxi were collected,and the contents of Pb,Hg,Cd,Cr,As,Cu,Zn,and Ni were determined to investigate the pollution characteristics and sources of heavy metals.ArcGIS inverse distance weight difference method was used to analyze the characteristics of pollution distribution,and single-factor pollution index,Nemerow comprehensive pollution index,ground accumulation index,and potential ecological risk index were selected to evaluate the characteristics of heavy metal pollution.Based on correlation analysis,the absolute principal component-multiple linear regression(APCS-MLR)and positive definite matrix factorization(PMF)models were used to analyze the sources of soil heavy metals.The results showed that the average concentrations of all eight heavy metals exceeded both national and Guangxi soil background values.Hg,Cd,and Zn exhibited high variation(greater than 0.5),indicating significant external disturbances,and their spatial distribution was closely related to mining activity locations.The single-factor pollution index evaluation indicated varying degrees of pollution risk for Cd,Zn,and As,with Cd and Zn being the most severe pollutants,as 69.23%and 30.77%of the samples fell into the moderate pollution or higher category.The geoaccumulation index analysis ranked the mean pollution levels of the eight elements as follows:Zn>Cd>Ni>Pb>Cu>Cr>Hg>As,with Cd and Zn showing the most severe contamination,and 51.28%of the samples exhibiting moderate or higher pollution levels.The Nemerow comprehensive pollution index evaluation showed that 74.35%of soil samples were classified as moderate to heavy pollution.The potential ecological risk index assessment indicated significant ecological risks posed by Cd and Zn,with 82.05%and 5.12%of the samples classified as causing strong to extreme ecological risks,respectively.The source apportionment analysis revealed minor differences between the two models.The APCS-MLR model identified three pollution sources and their contribution rates:anthropogenic mining sources(31.13%),parent material sources(40.38%),and unidentified sources(28.49%).The PMF model identified three pollution sources with contribution rates of anthropogenic mining sources(26.10%),parent material sources(46.96%),and a combined traffic and agricultural source(26.61%).Pb,Hg,Cd,and Zn mainly originated from mining activities;Cr,As,and Ni were primarily derived from the parent material,while Cu was predominantly attributed to traffic and agricultural sources.These findings provide a scientific basis for the prevention and control of heavy metal pollution in mining areas.
基金supported by Deep Earth Probe and Mineral Resources Exploration-National Science and Technology Major Project(Grant No.2024ZD1003705)the Beijing Nova Program(Grant No.20220484057)support from China Scholarship Council under Grant CSC No.202110300001.
文摘Stability of base-exposed backfill roof in underhand drift-and-fill mining is crucial for the safety of those working beneath.Given the commonly used primary-and-secondary mining sequence,interfaces are formed between adjacent filled drifts,which can weaken the integrity of the backfill roof.These interfaces also lead to two common drift layouts:aligned drifts and staggered drifts.However,less attention has been paid to the interfaces and the two drift layouts were not adequately distinguished in previous studies.In this paper,the interfaces between filled drifts were firstly considered to investigate the stability of backfill roof.Failure modes and strength requirements of backfill roof in aligned and staggered drifts are comprehensively investigated by FLAC3D,with a focus on considerations of varied shear parameters of the interfaces.Results show that failure modes in aligned drifts transition from block sliding to top caving,bottom caving or sloughing as the interface cohesion increases from zero to at least half of the backfill cohesion.Further increases in interface cohesion allow aligned drifts to behave as if there are no interfaces between them.The critical stability conditions of backfill roof in aligned drifts were mostly determined by the interface strength instead of the backfill strength.However,the stability of backfill roof in staggered drifts is barely affected by the interface strength.The outcomes are expected to provide references for mining engineers to optimize drift layouts and perform cost-effective backfill roof strength design at mines using underhand drift-and-fill mining method.
基金financially supported by the Guizhou Provincial Basic Research Program(Natural Science)(ZD[2025]007)the Guizhou Provincial Program on Commercialization of Scientific and Technological Achievements(N0.QKHCG-LH2024-ZD025)the National Natural Science Foundation of China(Grant No.42067046)。
文摘Deep karst fractures significantly drive rock strata movement induced by mining and are one of the key factors causing slope failures.Understanding the disaster formation mechanisms of mining-induced slopes controlled by deep karst fractures is crucial for geological hazard prevention and mitigation.Existing research on slope failure mechanisms under the coupled influence of deep karst fractures and underground coal mining remains limited and insufficiently developed.Consequently,this study establishes a coupled geomechanical model of mining-karst interaction for layered reverse-dip slopes in southwestern China.By integrating field investigations with discrete element simulations,this study explores the deformation characteristics and failure mechanisms of deeply fractured karst slopes subjected to underground mining,along with their impacts on slope stability.The main findings are as follows:(1)Deep rock karst fractures dominated the spatial distribution of tensile fracture zones,forming a dynamic stress arch effect above the goaf;(2)The mining process dynamically induced a three-stage destruction mode of the slope,namely,the bending effect caused by the dynamic stress arch,arch migration,and the evolution of the unlocking of the locking rocks;(3)Significant spatiotemporal variability existed between the tensile zone at the top of the slope and the shear zone on the slope surface,leading to the gradual overturning of the cantilever beam structure along the dominant structural surface.It indicates that deep rock karst fractures are the primary factor controlling the disaster of the cantilever beam structure,exacerbating the degree of rock fracture and surface subsidence induced by coal mining.This study reveals the chain disaster mechanism of layered anti-dip rock karst fracture slopes in southwestern China,namely,fracture penetration,rock stratum movement-induced failure,unlocking of key rocks,and final tensile overturning destruction,profoundly elucidating the critical role of rock dissolution fissures in mining-induced slope disasters.
基金Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering with grant at Ocean University of China,Grant/Award Numbers:MEGE2024001,MEGE2024002National Natural Science Foundation of China,Grant/Award Number:42207181+2 种基金Fundamental Research Funds for the Central Universities,Grant/Award Number:202441003Opening Fund of the State Key Laboratory of Coastal and Offshore Engineering at Dalian University of Technology,Grant/Award Number:LP2310National Key Research and Development Program of China,Grant/Award Number:2024YFC2815400。
文摘Comprehending the flow behavior of deep-sea mining plumes is paramount for precise predictions of their propagation range and holds immense significance in advancing the commercial exploitation of deep-sea minerals.As deep-sea mining plumes propagate,they can transition from high-density non-Newtonian fluids to low-density Newtonian fluids.However,a comprehensive rheological model capable of accurately describing this intricate evolutionary process is currently lacking.This study explores the variations in rheological properties observed during the propagation of deep-sea mining plumes,utilizing rheological test data obtained from kaolin clay plumes.Utilizing the Power Law model,we established a power exponential function correlating the plume rheological parameters(consistency index and flow behavior index)with a density range from 1.00 to 1.50 g/cm3 through data fitting,developing a rheological model of deep-sea mining plumes considering the variations in plume density.Subsequently,taking into account the differences in sediment properties,the effects of clay content and clay mineral composition on the rheological parameters of natural sediment plumes were compared and analyzed.This model provides a reference for understanding the rheological properties of deep-sea mining plumes during their propagation.
基金sponsored by the Alpha Foundation for the Improvement of Mine Safety and Health,Inc.(ALPHA FOUNDATION).
文摘The failure and collapse of coal pillar ribs represent a significant hazard in the mining industry,with the associated risk of fatalities and injuries anticipated to rise as mining operations advance to greater depths.The development of support guidelines through an enhanced understanding of pillar damage and rock–support interaction mechanisms is crucial to resolving this issue.Bonded block models(BBMs)represent a convenient tool for this purpose,as they can reasonably reproduce the rock fracturing process;however,it is not known to what extent this modeling technique can be applied to simulate pillar failure mechanisms and support interaction in anisotropic rock masses,such as coal.To bridge this gap in research,hypothetical coal pillar BBMs of different width-to-height ratios were developed and calibrated to match Mark–Bieniawski's pillar strength equation,along with a few other attributes from the literature(stress levels at the edge of pillars and the transition from brittle to strain-hardening behavior with increasing width-to-height ratio).Elongated blocks were employed to capture the anisotropic behavior of coal mass.With the reliability of the model established,a few different support patterns were evaluated to ensure that the outputs are broadly consistent with expectations.Finally,simulations of roadway development and additional mining activities were completed considering geo-mining conditions representative of underground coal mines in the USA.The good consistency between model response and expected behaviors per field observation demonstrates the potential of BBMs to be used as a support design tool.
基金supported by the National Natural Science Foundation of China(Grant No.52374148,52204163)the Fundamental Research Funds for the Cornell University(Grant No.2025JCCXNY02)the Open Fund of Key Laboratory of Xinjiang Coal Resources Green Mining,Ministry of Education(Grant No.KLXGY-KB2408).
文摘The sublevel top coal caving(SLTCC)mining is widely employed in steeply inclined and thick coal seams.In SLTCC,the large coal drawing height and the influence of roof and floor boundaries introduce significant complexity into the coal extraction process.The study demonstrates that,in an SLTCC working face,the granular nature of top coal gives rise to a'locking-embedding'effect and a'loosening-compaction'cycle during the drawing process.These phenomena invalidate several core assumptions of the conventional Bergmark-Roos(B-R)model,which is no longer fully established,and the maximum moving angle changes dynamically.Therefore,an improved B-R model was proposed to account for the dynamic variations in particle shape and maximum transport angle,and the corresponding boundary equations of the drawing body were derived.Additionally,a novel numerical simulation method based on the rolling resistance linear model(RRLM),which takes into account particle shape,has been introduced.Validation was conducted through numerical simulations and physical experiments.Both numerical and physical tests confirmed that the improved B-R model more accurately captures the drawing body shape in SLTCC.Field measurement data in Wudong coal mine in Xinjiang,China,further substantiated the model's validity.In addition,as sublevel height increases,the drawing body exhibits markedly different evolution trends on the roof-and floor-side boundaries.Formulas for the improved B-R model at various sublevel heights were established.The research may provide new approaches for SLTCC simulations and theoretical calculations of drawing body shape at different sublevel heights.
基金Project(10872218) supported by the National Natural Science Foundation of ChinaProject(2010CB732004) supported by the National Key Basic Research Program of China+1 种基金Project(20090461022) supported by the National Postdoctoral Foundation of ChinaProject (11MX21) supported by the Students' Innovation Project Aubsidize Award of Arcelor Mittal
文摘Xinli district of Sanshandao Gold Mine is the first subsea metal mine in China.To achieve 6 kt/d production capacity under the premise of safe mining,high-intensity mining might destroy the in-situ stress filed and the stability of rockmass.According to sampling and testing of ore-rock and backfill and in-situ stress field measurement,safety factor method calculation model based on stress-strain strength reduction at arbitrary points and Mohr-Coulomb yield criterion was established and limit displacement subsidence values under the safety factor of different limit stoping steps were calculated.The results from three years in-situ mining and strata movement monitoring using multi-point displacements meter showed that the lower settlement frame stope hierarchical level filling mining method,mining sequence are reasonable and rockmass stability evaluation using safety factor method,in-situ real-time monitoring can provide the technical foundation for the safety of seabed mining.
