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Technical parameters of drawing and coal-gangue field movements of a fully mechanized large mining height top coal caving working face 被引量:7
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作者 LIU Chang-you HUANG Bing-xiang WU Feng-feng 《Mining Science and Technology》 EI CAS 2009年第5期549-555,共7页
Under fully mechanized, large mining height top coal caving conditions, the shield beam slope angle of the support increases due to the enlargement of the top coal breaking and caving space. This results in a change o... Under fully mechanized, large mining height top coal caving conditions, the shield beam slope angle of the support increases due to the enlargement of the top coal breaking and caving space. This results in a change of the caving window location and dimensions and, therefore, the granular coal-gangue movement and flows provide new characteristics during top coal caving. The main inferences we draw are as follows. Firstly, after shifting the supports, the caved top coal layer line and the coal gangue boundary line become steeper and are clearly larger than those under common mining heights. Secondly, during the top coal caving procedure, the speed of the coal-gangue flow increases and at the same drawing interval, the distance between the coal-gangue boundary line and the top beam end is reduced. Thirdly, affected by the drawing ratio, the slope angle of the shield beam and the dimensions of the caving window, it is easy to mix the gangue. A rational drawing interval will cause the coal-gangue boundary line to be slightly behind the down tail boom lower boundary. This rational drawing interval under conditions of large mining heights has been analyzed and determined. 展开更多
关键词 large mining height top coal caving coal-gangue movement field coal caving technical parameters coal caving window
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Similar material simulation research on movement law of roof over-lying strata in stope of fully mechanized caving face with large mining height 被引量:2
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作者 ZHU Yong-jian PENG Gang 《Journal of Coal Science & Engineering(China)》 2010年第1期6-10,共5页
Similar material simulation test W9-15 101 fully mechanized caving face with was carried out in a geological model of large mining height in the Liuhuanggou Colliery, in Xinjiang Uigur Autonomous Region. The roof over... Similar material simulation test W9-15 101 fully mechanized caving face with was carried out in a geological model of large mining height in the Liuhuanggou Colliery, in Xinjiang Uigur Autonomous Region. The roof overlying strata movement law in the stope of a fully mechanized caving face with large mining height was studied and show that the roof overlying strata in the stope of a fully mechanized caving face with large mining height can be formed into a stable arch structure; the fracture rock beam is formed resembling a "bond beam", but it has essentially the structure of "multi-span beams" under the big structure of the stable arch. The roof overlying strata movement law in the stope of a fully mechanized caving face with large mining height is similar to that of the common, fully mechanized caving stope, which is determined by the deformation and instability of the structure of "multi-span beams". But because of the differences between the mining heights, the peak pressure in the stope of a fully mechanized caving face with large mining height is smaller while the affected area of abutment pressure is wider in the front of the working face; this is the obvious difference in abutment pressure between the stope of a fully mechanized caving face with large mining height and that of the common. 展开更多
关键词 fully mechanized caving face with large mining height STOPE roof overlyingstrata stable arch structure
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Technological optimization of fully mechanized caving mining face with large mining heights 被引量:1
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作者 Lu-Jia FAN Sheng-Li YANG 《Journal of Coal Science & Engineering(China)》 2013年第3期290-294,共5页
Fully mechanized cave mining with large mining height is a new mining method, due to its large mining thickness and lower roadway excavation, the technology has been widely used in China's thick seam mining. In order... Fully mechanized cave mining with large mining height is a new mining method, due to its large mining thickness and lower roadway excavation, the technology has been widely used in China's thick seam mining. In order to improve the top-coal recovery ratio of fully mechanized cave mining with large mining height, a study was conducted on optimizing the caving process, based on the mechanized caving face 1302N in Longgu Coal Mine. This was achieved by improving the PFC numerical calculation methods, and establishing a more accurate model system. On this basis, the recovery ratio of the top coal in different drawing intervals and technologies was investigated in order to achieve a reasonable caving process. The top-coal tracking system was used for practical surveying of the recovery ratio of top coal. 展开更多
关键词 fully mechanized caving face large mining height caving process optimization numerical calculation by PFC top-coal tracking system
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The influence of inter-band rock on rib spalling in longwall panel with large mining height 被引量:1
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作者 Jiachen Wang Meng Li +3 位作者 Zhaohui Wang Zheng Li Han Zhang Shixiong Song 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第4期427-442,共16页
In order to improve rib stability,failure criteria and instability mode of a thick coal seam with inter-band rock layer are analysed in this study.A three-dimensional mechanical model is established for the rib by con... In order to improve rib stability,failure criteria and instability mode of a thick coal seam with inter-band rock layer are analysed in this study.A three-dimensional mechanical model is established for the rib by considering the rock layer.A safety factor is defined foy the rib,and it is observed that the safety factor exhibits a positive correlation with the thickness and strength of the inter-band rock.A calculation method for determining critical parameters of the rock layer is presented to ensure the rib stability.It is revealed that incomplete propagation of the fracture at the hard rock constitutes a fundamental prerequisite for ensuring the rib stability.The influence of the position of the inter-band rock in the coal seam on failure mechanism of the rib was thoroughly investigated by developing a series of physical models for the rib at the face area.The best position for the inter-band rock in the coal seam is at a height of 1.5 m away from the roof line,which tends to provide a good stability state for the rib.For different inter-band rock positions,two ways of controlling rib by increasing supports stiffness and flexible grouting reinforcement are proposed. 展开更多
关键词 Rib spalling Inter-band rock large mining height Limit analysis Physical model experiment Numerical simulation
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Key technologies and equipment for a fully mechanized top-coal caving operation with a large mining height at ultra-thick coal seams 被引量:61
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作者 Jinhua Wang Bin Yu +4 位作者 Hongpu Kang Guofa Wang Debing Mao Yuntao Liang Pengfei Jiang 《International Journal of Coal Science & Technology》 EI 2015年第2期97-162,共66页
Thick and ultra-thick coal seams are main coal seams for high production rate and high efficiency in Chinese coal mines, which accounts for 44 % of the total minable coal reserve. A fully mechanized top-coal caving mi... Thick and ultra-thick coal seams are main coal seams for high production rate and high efficiency in Chinese coal mines, which accounts for 44 % of the total minable coal reserve. A fully mechanized top-coal caving mining method is a main underground coal extraction method for ultra-thick coal seams. The coal extraction technologies for coal seams less than 14 m thick were extensively used in China. However, for coal seams with thickness greater than 14 m, there have been no reported cases in the world for underground mechanical extraction with safe performance, high efficiency and high coal recovery ratio. To deal with this case, China Coal Technology & Engineering Group, Datong Coal Mine Group, and other 15 organizations in China launched a fundamental and big project to develop coal mining technologies and equipment for coal seams with thicknesses greater than 14 m. After the completion of the project, a coal extraction method was developed for top-coal caving with a large mining height, as well as a ground control theory for ultra-thick coal seams. In addition, the mining technology for top-coal caving with a large mining height, the ground support technology for roadway in coal seams with a large cross-section, and the prevention and control technology for gas and fire hazards were developed and applied. Furthermore, a hydraulic support with a mining height of 5.2 m, a shearer with high reliability, and auxiliary equipment were developed and manufactured. Practical implication on the technologies and equipment developed was successfully completed at the No. 8105 coal face in the Tashan coal mine, Datong, China. The major achievements of the project are summarized as follows: 1. A top-coal caving method for ultra-thick coal seams is proposed with a cutting height of 5 m and a top-coal caving height of 15 m. A structural mechanical model of overlying strata called cantilever beam-articulated rock beam is established. Based on the model, the load resistance of the hydraulic support with a large mining height for top-coal caving method is determined. With the analysis, the movement characteristics of the top coal and above strata are evaluated during top-coal caving operation at the coal face with a large mining height. Furthermore, there is successful development of comprehensive technologies for preventing and controlling spalling of the coal wall, and the top-coal caving technology with high efficiency and high recovery at the top-coal caving face with a large mining height. This means that the technologies developed have overcome the difficulties in strata control, top-coal caving with high efficiency and high coal recovery, and enabled to achieve a production rate of more than 10 Mtpa at a single top-coal caving face with a large mining height in ultra-thick coal seams; 2. A hydraulic support with 5.2 m supporting height and anti-rockburst capacity, a shearer with high reliability, a scraper conveyor with a large power at the back of face, and a large load and long distance headgate belt conveyor have been successfully developed for a top-coal caving face with large mining height. The study has developed the key technologies for improving the reliability of equipment at the coal face and has overcome the challenges in equipping the top-coal caving face with a large mining height in ultra-thick coal seams; 3. The deformation characteristics of a large cross-section roadway in ultra-thick coal seams are discovered. Based on the findings above, a series of bolt materials with a high yielding strength of 500-830 MPa and a high extension ratio, and cable bolt material with a 1 × 19 structure, large tonnage and high extension ratio are developed. In addition, in order to achieve a safe roadway and a fast face advance, installation equipment for high pre-tension bolt is developed to solve the problems with the support of roadway in coal seams for top-coal caving operation with a large mining height; 4. The characteristics of gas distribution and uneven emission at top-coal caving face with large mining height in ultra-thick coal seams are evaluated. With the application of the technologies of gas drainage in the roof, the difficulties in gas control for high intensive top-coal caving mining operations, known as "low gas content, high gas emission", are solved. In addition, large flow-rate underground mobile equipment for making nitrogen are developed to solve the problems with fire prevention and safe mining at a top-coal caving face with large mining height and production rate of more than 10 Mtpa. A case study to apply the developed technologies has been conducted at the No. 8105 face, the Tashan coal mine in Datong, China. The case study demonstrates that the three units of equipment, i.e., the support, shearer and scraper conveyor, are rationally equipped. Average equipment usage at the coal face is 92.1%. The coal recovery ratio at the coal face is up to 88.9 %. In 2011, the coal production at the No. 8105 face reached 10.849 Mtpa, exceeding the target of 10 Mtpa for a topcoal caving operation with large mining height performed by Chinese-made mining equipment. The technologies and equipment developed provide a way for extracting ultra-thick coal seams. Currently, the technologies and equipment are used in 13 mining areas in China including Datong, Pingshuo, Shendong and Xinjiang. With the exploitation of coal resources in Western China, there is great potential for the application of the technologies and equipment developed. 展开更多
关键词 Ultra-thick coal seams Top-coal caving mining large mining height mining method - mining equipment Roadway support Safety guarantee
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Mode of overlying rock roofing structure in large mining height coal face and analysis of support resistance 被引量:2
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作者 吴锋锋 刘长友 杨敬轩 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第12期3262-3272,共11页
The mining space of large mining height coal face is large,the range of movement and caving of rock strata is large and the stability of supports at coal face is low and damage rate of supports is high,which significa... The mining space of large mining height coal face is large,the range of movement and caving of rock strata is large and the stability of supports at coal face is low and damage rate of supports is high,which significantly affects the safe and efficient production of coal mines.By similar simulation experiment and theoretical analysis,the mode of fractured roofing structure of large mining height coal face and the method of determination of reasonable support resistance of the support was evaluated.Analysis shows that the structural mode of "combined cantilever beam – non-hinged roofing – hinged roofing" of the large mining height coal face appears at the roofing of large mining height coal face.The supporting factor of caved gangue at the gob is introduced,the calculating equations of the fractured step distance of roofing were derived and conventional calculating method of caved height of roofing was corrected and the method of determination of the length and height of each structural area of the roofing was provided.With reference to the excavating conditions at Jinhuagong coal mine in Datong minefield,the dimensions of structural areas of the roofing of the coal face were determined and analyzed,and reasonable support resistance of the height coal face was acquired.By selecting Model ZZ13000/28/60 support and with procedures of advanced pre-cracking blasting,the safe production of large mining height coal face was assured. 展开更多
关键词 large mining height roof structure roof model roof fracturing distance support resistance
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Suitable retention and recovery technology of floor coal at ends of fully mechanized face with great mining heights 被引量:3
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作者 Zhang Nenghu Wu Qi +1 位作者 YuanYong Bai Qingsheng 《Mining Science and Technology》 EI CAS 2011年第2期281-285,共5页
Gateways at faces of great mining heights are mostly driven along the roof of coal seams.For gateway height restrictions,a 1-3 m floor coal is retained,leaving a triangular floor coal at the face ends,causing a loss o... Gateways at faces of great mining heights are mostly driven along the roof of coal seams.For gateway height restrictions,a 1-3 m floor coal is retained,leaving a triangular floor coal at the face ends,causing a loss of coal.In order to improve coal recovery rates and to ensure efficiency of equipment at coal mining faces,we investigated suitable retention methods and recovery technology of floor coal at face ends.The upper floor coal can directly be recovered by a shearer with floor dinting.The lower floor coal is recovered by shearer with floor dinting after advanced floor dinting and retaining a step for protecting coal sides in a haulage gateway.Field practice shows that this method can improve the coal recovery rates at fully mechanized working faces with great mining heights. 展开更多
关键词 Great mining heights Floor coal at face ends Floor coal recovery Floor dinting Step for protecting coal side
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Analysis and control of hydraulic support stability in fully-mechanized longwall face to the dip with great mining height
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作者 华心祝 王家臣 《Journal of Coal Science & Engineering(China)》 2008年第3期399-402,共4页
The working condition of the hydraulic support in working face can be divided into three kinds of situations in the following: roof fall and col,lapse with cavity, advancing support and supporting. Took single suppor... The working condition of the hydraulic support in working face can be divided into three kinds of situations in the following: roof fall and col,lapse with cavity, advancing support and supporting. Took single support with four-pole in Iongwall face to the dip as research object, control method was studied to avoid support instability in three situations mentioned above. Based on these researches, the major factors of influencing on support stability and its controlling measures were put forward. According to specific conditions of working face 1215(3), which is fully-mechanized and Iongwall face to the dip with great mining height in Zhangji Coal Mine, Huainan Mining Group, the effective measures was taken to control supports stability.. 展开更多
关键词 longwall face to the dip fully-mechanized working face with great mining height supports stability control
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Experimental investigation into stress-relief characteristics with upward large height and upward mining under hard thick roof 被引量:21
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作者 Ke Yang Xiang He +3 位作者 Litong Dou Wenjun Liu Li Sun Haisong Ye 《International Journal of Coal Science & Technology》 EI 2015年第1期91-96,共6页
According to geological conditions of No. 3 and No. 4 coal seams (namely A3 and B4) of the Pan'er coal mine and the parameters of panels 11223, 11224, and 11124 with fully-mechanical coal mining, we built 2D simila... According to geological conditions of No. 3 and No. 4 coal seams (namely A3 and B4) of the Pan'er coal mine and the parameters of panels 11223, 11224, and 11124 with fully-mechanical coal mining, we built 2D similar material simulation and FLAC3D numerical simulation models to investigate the development of mining-induced stress and the extraction effect of pressure-relief gas with large height and upward mining. Based on a comprehensive analysis of experimental data and observations, we obtained the deformation and breakage characteristics of strata overlying the coal seam, the development patterns of the mining-induced stress and fracture, and the size of the stress-relief area. The stress-relief effect was investigated and analyzed in consideration with mining height and three thick hard strata. Because of the group of three hard thick strata located in the main roof and the residual stress of mined panel 11124, the deformation, breakage, mining-induced stress and fracture development, and the stress-relief coefficient were discontinuous and asymmetrical. The breakage angle of the overlying strata, and the compressive and expansive zones of coal deformation were mainly controlled by the number, thickness, and strength of the hard stratum. Compared with the value of breakage angle derived by the traditional empirical method, the experimental value was lower than the traditional results by 3°-4°below the hard thick strata group, and by 13°-19° above the hard thick strata group. The amount of gas extracted from floor drainage roadway of B4 over 17 months was variable and the amount of gas per month differed considerably, being much smaller when panel 11223 influenced the area of the three hard thick strata. Generally, the stress-relief zone of No. 4 coal seam was small under the influence of the hard thick strata located in the main roof, which played an important role in delaying the breakage time and increasing the breakage space. In this study we gained understanding of the stress-relief mechanism influenced by the hard thick roof. The research results and engineering practice show that the main roof of the multiple hard thick strata is a critical factor in the design of panel layout and roadways for integrated coal exploitation and gas extraction, provides a theoretical basis for safe and high-efficient mining of coal resources. 展开更多
关键词 Integrated coal exploitation and gas extraction large mining height Stress-relief effect Hard thick strata mining-induced stress
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Effect of suppressing dust by multi-direction whirling air curtain on fully mechanized mining face 被引量:6
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作者 Nie Wen Liu Yanghao +3 位作者 Wei Wenle Hu Xiangming Ma Xiao Peng Huitian 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第4期629-635,共7页
A combined method of numerical simulation and field testing was adopted in this study in the interest of solving the problem of hard to control high concentrate dusts on a fully mechanized mining face. In addi- tion, ... A combined method of numerical simulation and field testing was adopted in this study in the interest of solving the problem of hard to control high concentrate dusts on a fully mechanized mining face. In addi- tion, the dust suppression effect of a multi-direction whirling air curtain was studied in this paper. Under the influence of the wall attachment effect, the compressed air which blows out from the two-phase or three-phase radial outlets on the generator of the air curtain can form a multi-direction whirling air curtain, which can cover the whole roadway section of a fully mechanized mining face. The traditional method of controlling dust is a forcing system with exhaust overlap which has the major disadvantage of lacking a jet effect and consequently results in poor dust control. It is difficult to form the air flow field within the range of Lp ≤ 5√S. However, due to the effect of this novel system, the radial airflow can be turned into axial airflow allowing fresh air to flow through the length of the heading. The air flow field which is good at controlling dust diffusion can be formed 12.8 m from the heading face. Furthermore, the field measurement results show that before the application of a multi-direction whirling air curtain, the dust concentration is 348.6 mg/m^3 and 271.4 mg/m^3 respectively at the roadway cross-section measurement points which are 5 m and 10 m from the heading face. However, after the application of the multi-direction whirling air curtain, the dust concentration is only 61.2 mg/m3 and 14.8 mg/m^3, respectively. Therefore, the dust control effect of a multi-direction whirling air curtain is obvious. 展开更多
关键词 Fully mechanized mining face Compressed air Multi-directional whirling air curtain AirflowDust suppression
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Study on the characteristics of ground pressure behaviors in working face with great mining height at different advance speeds by similarity model experiment
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作者 华心祝 张金龙 谢广祥 《Journal of Coal Science & Engineering(China)》 2007年第1期28-31,共4页
Presently most of research results on strata behaviors were concluded under the normal (moderate) advance rate conditions. Comparing with normal advance rate, fast advance rate and slow advance rate may cause some n... Presently most of research results on strata behaviors were concluded under the normal (moderate) advance rate conditions. Comparing with normal advance rate, fast advance rate and slow advance rate may cause some new changes of strata behaviors. The characteristics of ground pressure behaviors in working face with great mining height at different forward speeds were studied by similarity model experiment in laboratory. Its conclusion provides a theoretic basis for ground pressure controlling. 展开更多
关键词 similarity simulation advance rate working face with great mining height ground pressure
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Back-and-forth mining for hard and thick coal seams—research about the mining technology for fully mechanized caving working face of Datong Mine
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作者 金智新 于红 +1 位作者 于斌 宋华岭 《Journal of Coal Science & Engineering(China)》 2005年第2期1-4,共4页
The article introduced the key technology, mining process, and back-and-forth mining method for the caving working face of hard-thick coal seams in Datong mine, and researched this innovations process, optimized the s... The article introduced the key technology, mining process, and back-and-forth mining method for the caving working face of hard-thick coal seams in Datong mine, and researched this innovations process, optimized the systemic design and working face out-play, tried to perfect the caving mining technology of hard-thick coal seams further. 展开更多
关键词 hard and thick coal seams fully mechanized caving working face back-and- forth mining
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Development and prospect on fully mechanized mining in Chinese coal mines 被引量:104
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作者 Jinhua Wang 《International Journal of Coal Science & Technology》 EI CAS 2014年第3期253-260,共8页
Fully mechanized mining(FMM)technology has been applied in Chinese coal mines for more than 40 years.At present,the output of a FMM face has reached 10-million tons with Chinese-made equipment.In this study,the new de... Fully mechanized mining(FMM)technology has been applied in Chinese coal mines for more than 40 years.At present,the output of a FMM face has reached 10-million tons with Chinese-made equipment.In this study,the new developments in FMM technology and equipment in Chinese coal mines during past decades are introduced.The automatic FMM technology for thin seams,complete sets of FMM technology with ultra large shear height of 7 m for thick seams,complete sets of fully mechanized top coal caving technology with large shear height for ultra-thick seams of 20 m,complete sets of FMM technology for complex and difficult seams,including steeply inclined seams,soft coal seams with large inclination angle,and the mechanized filling mining technology and equipment are presented.Some typical case studies are also introduced.Finally,the existing problems with the FMM technology are discussed,and prospect of FMM technology and equipment applied in Chinese coal mines is put forward. 展开更多
关键词 Fully mechanized mining mining with large shear height Fully mechanized top coal caving Steeply inclined seam Back filling mining PROSPECT
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Ground pressure and overlying strata structure for a repeated mining face of residual coal after room and pillar mining 被引量:10
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作者 Jiang Bangyou Wang Lianguo +2 位作者 Lu Yinlong Sun Xiaokang Jin Gan 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第4期645-652,共8页
To investigate the abnormal ground pressures and roof control problem in fully mechanized repeated mining of residual coal after room and pillar mining, the roof fracture structural model and mechanical model were dev... To investigate the abnormal ground pressures and roof control problem in fully mechanized repeated mining of residual coal after room and pillar mining, the roof fracture structural model and mechanical model were developed using numerical simulation and theoretical analysis. The roof fracture characteristics of a repeated mining face were revealed and the ground pressure law and roof supporting condi- tions of the repeated mining face were obtained. The results indicate that when the repeated mining face passes the residual pillars, the sudden instability causes fracturing in the main roof above the old goal and forms an extra-large rock block above the mining face. A relatively stable "Voussoir beam" structure is formed after the advance fracturing of the main roof. When the repeated mining face passes the old goaf, as the large rock block revolves and touches gangue, the rock block will break secondarily under overburden rock loads. An example calculation was performed involving an integrated mine in Shanxi province, results showed that minimum working resistance values of support determined to be reason- able were respectively 11,412 kN and 10,743 kN when repeated mining face passed through residual pillar and goaf. On-site ground pressure monitoring results indicated that the mechanical model and support resistance calculation were reasonable. 展开更多
关键词 Residual coal after room and pillar mining Repeated mining Fully mechanized caving face Roof control Support resistance
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STUDY ON PRODUCTION SYSTEM OPERATION REGULARITY OF FULLY MECHANIZED SUBLEVEL CAVING MINING AND SEQUENTIAL OPERATION
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作者 李学忠 王新淮 陈永文 《Journal of Coal Science & Engineering(China)》 1998年第1期30-35,共6页
According to a lot of practical data in Liujialiang Mine and reliability theory and result of computer simulation, operation regularity of fully mechanized sublevel caving mining production system in the condition of ... According to a lot of practical data in Liujialiang Mine and reliability theory and result of computer simulation, operation regularity of fully mechanized sublevel caving mining production system in the condition of gently inclined complicated geological structure and production shortcomings are found out and reliability of system and output of the working face are predicted finally. 展开更多
关键词 fully mechanized sublevel caving mining face sequential operation computer simulation reliability theory
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Systematic principles of surrounding rock control in longwall mining within thick coal seams 被引量:9
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作者 Jiachen Wang Zhaohui Wang 《International Journal of Mining Science and Technology》 EI CSCD 2019年第1期65-71,共7页
Effective surrounding rock control is a prerequisite for realizing safe mining in underground coal mines.In the past three decades, longwall top-coal caving mining(LTCC) and single pass large height longwall mining(SP... Effective surrounding rock control is a prerequisite for realizing safe mining in underground coal mines.In the past three decades, longwall top-coal caving mining(LTCC) and single pass large height longwall mining(SPLL) found expanded usage in extracting thick coal seams in China. The two mining methods lead to large void space left behind the working face, which increases the difficulty in ground control.Longwall face failure is a common problem in both LTCC and SPLL mining. Such failure is conventionally attributed to low strength and high fracture intensity of the coal seam. However, the stiffness of main components included in the surrounding rock system also greatly influences longwall face stability.Correspondingly, surrounding rock system is developed for LTCC and SPLL faces in this paper. The conditions for simultaneous balance of roof structure and longwall face are put forward by taking the stiffness of coal seam, roof strata and hydraulic support into account. The safety factor of the longwall face is defined as the ratio between the ultimate bearing capacity and actual load imposed on the coal wall.The influences provided by coal strength, coal stiffness, roof stiffness, and hydraulic support stiffness,as well as the movement of roof structure are analyzed. Finally, the key elements dominating longwall face stability are identified for improving surrounding rock control effectiveness in LTCC and SPLL faces. 展开更多
关键词 LONGWALL top coal CAVING mining Single PASS large height LONGWALL mining SURROUNDING rock system LONGWALL face stability
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The Recent Technological Development of Intelligent Mining in China 被引量:36
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作者 Jinhua Wang Zenghua Huang 《Engineering》 SCIE EI 2017年第4期439-444,共6页
In the last five years, China has seen the technological development of intelligent mining and the application of the longwall automation technology developed by the Longwall Automation Steering Committee. This paper ... In the last five years, China has seen the technological development of intelligent mining and the application of the longwall automation technology developed by the Longwall Automation Steering Committee. This paper summarizes this great achievement, which occurred during the 12th Five-Year Plan (2011-2015), and which included the development of a set of intelligent equipment for hydraulic-powered supports, information transfers, dynamic decision-making, performance coordination, and the achievement of a high level of reliability despite difficult conditions. Within China, the intelligent system of a set of hydraulic-powered supports was completed, with our own intellectual property rights. An intelligent mining model was developed that permitted unmanned operation and single-person inspection on the work face. With these technologies, the number of miners on the work face can now be significantly reduced. Miners are only required to monitor mining machines on the roadway or at the surface control center, since intelligent mining can be applied to extract middle-thick or thick coal seams. As a result, miners' safety has been improved. Finally, this Darter discusses theprospects and challenges of intelligent mining over the next ten years. 展开更多
关键词 Coal mineIntelligent mining mechanized mining work face Longwall Automation Steering CommitteeIntelligent service center
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煤矿井下非均匀照度图像去噪研究 被引量:1
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作者 张旭辉 麻兵 +2 位作者 杨文娟 董征 李语阳 《工矿自动化》 CSCD 北大核心 2024年第2期1-8,共8页
煤矿综采工作面空间小、照明环境复杂多变,采煤过程中伴随着大量的粉尘、大雾,导致采集的图像出现曝光、细节特征减弱等问题,难以对井下照明区域光照强度过大的图像进行有效的特征提取。针对上述问题,提出了一种煤矿井下非均匀照度图像... 煤矿综采工作面空间小、照明环境复杂多变,采煤过程中伴随着大量的粉尘、大雾,导致采集的图像出现曝光、细节特征减弱等问题,难以对井下照明区域光照强度过大的图像进行有效的特征提取。针对上述问题,提出了一种煤矿井下非均匀照度图像去噪算法。首先,将视频截取为图像,判断图像是否需要进行光照抑制,将需要进行光照抑制的RGB图像拆分通道,并计算每个通道的光照调节因子,实现图像的整体光照调节;然后,将未进行整体光照抑制的图像和经整体光照抑制的图像进行反射分量提取,即将输入的图像转换为HSV空间图像,使用单尺度Retinex(SSR)算法对V通道图像中的光照分量进行单独处理,将V分量中的入射分量去除,保留反射分量,并对反射分量使用直方图均衡算法实现光照均衡化处理;最后,使用基于引导滤波的暗通道先验算法对经过光照处理后的图像进行去雾处理,并使用伽马校正函数重新调节亮度不均的图像。主观评价结果表明:提出的煤矿井下非均匀照度图像去噪算法有效抑制了因光照导致整体亮度较高的问题,且由于大雾、粉尘等因素导致图像模糊的部分更加清晰,图像的细节特征更加突出。采用信息熵、均值、标准差、空间频率4种评价指标对提出的算法效果进行客观评价,结果表明,提出的算法在信息熵、均值、标准差、空间频率上较多尺度Retinex(MSR)算法分别平均提升了21.87%,-56.06%,153.43%,294.45%,较基于颜色保持的多尺度视网膜增强(MSRCP)算法分别平均提升了1.18%,-39.56%,33.29%,-4.71%,较带色彩恢复的多尺度视网膜增强(MSRCR)算法分别平均提升了38.06%,-55.27%,462.10%,300.96%,说明提出的算法能更有效地增加图像信息量、抑制光照强度、提升边缘信息及图像清晰度。 展开更多
关键词 综采工作面 煤矿井下图像去噪 非均匀光照 高光抑制 亮度均衡 图像去雾 伽马校正
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松软煤层大采高工作面煤壁片帮机理及深浅孔交替超前预注浆加固技术研究 被引量:1
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作者 陈晓祥 韩文宇 《河南理工大学学报(自然科学版)》 CAS 北大核心 2024年第3期11-22,共12页
目的为探究松软煤层大采高工作面煤壁片帮机理,并对片帮严重的松软煤层大采高工作面煤壁进行有效控制,方法利用材料力学理论得到煤壁片帮的频发位置,引入煤壁剪切破坏准则,得出松软煤体煤壁片帮的主控因素。并以李村煤矿1305工作面为例... 目的为探究松软煤层大采高工作面煤壁片帮机理,并对片帮严重的松软煤层大采高工作面煤壁进行有效控制,方法利用材料力学理论得到煤壁片帮的频发位置,引入煤壁剪切破坏准则,得出松软煤体煤壁片帮的主控因素。并以李村煤矿1305工作面为例,通过FLAC3D建立数值模型,以煤壁最大位移、煤体破坏深度、支承压力大小和支承压力峰值位置4个因素作为参考比较对象,通过引入正交试验法,研究了煤层埋深、内摩擦角、黏聚力、抗拉强度以及支护强度对煤壁片帮的影响程度。结果结果表明:煤体自身的物理力学性质(内摩擦角和黏聚力)是影响煤壁片帮的主要因素,其次煤体的赋存条件(埋深)也是一个较为关键的影响因素。结论工业性试验基于正交试验结果提出了大采高综采工作面深浅孔交替超前预注浆加固技术,有效控制了李村煤矿1305工作面煤壁片帮严重情况,为其他类似地质条件大采高综采工作面煤壁片帮控制提供了借鉴。 展开更多
关键词 大采高 松软煤层 煤壁片帮 正交试验 数值模拟
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厚煤层大采高综放工作面覆岩断裂演化规律研究 被引量:1
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作者 刘洪涛 罗紫龙 +3 位作者 韩子俊 韩洲 陈小港 彭佳琛 《煤炭科学技术》 EI CAS CSCD 北大核心 2024年第3期1-12,共12页
大采高综放开采易形成强烈的矿压显现,上覆岩层的断裂演化规律对工作面安全生产至关重要。以羊场湾煤矿160206工作面为工程背景,运用相似模拟试验、数值模拟和理论分析的综合研究方法,对大采高综放工作面覆岩的断裂过程与覆岩运移规律... 大采高综放开采易形成强烈的矿压显现,上覆岩层的断裂演化规律对工作面安全生产至关重要。以羊场湾煤矿160206工作面为工程背景,运用相似模拟试验、数值模拟和理论分析的综合研究方法,对大采高综放工作面覆岩的断裂过程与覆岩运移规律进行系统研究。研究表明:导水裂隙带内岩层随工作面推进表现为“台阶下沉”,同层岩层下沉趋势沿走向表现为“急剧下降—稳定(最大值)—快速上升—稳定(最小值)”。工作面覆岩运动场由两区分布(加速下沉区、缓慢下沉区)演化为三区分布(加速下沉区、缓慢下沉区、稳定区)。对离层演化与地表下沉规律进行了定量描述,运用理论计算表达式深入地剖析了地表的动态下沉机理及其相关因素。结合相似模拟与数值模拟的试验结果,提出了覆岩断裂演化的形态变化特征:覆岩断裂形态由“单等腰梯形”演化为“双等腰梯形”,表土层影响区由“矩形”演化为“倒梯形”。分析了覆岩中垮落区、离层区、压实区、裂隙富集区的动态演化过程:垮落区逐渐增大至一定程度,高度小幅度降低并趋于稳定,离层区由下至上逐渐发育并随工作面向前移动,离层区逐渐闭合形成压实区,且压实区逐渐增大并最终保持稳定,裂隙富集区位于采空区前后端部并随工作面向前移动。 展开更多
关键词 大采高综放 相似模拟 覆岩运动场 覆岩运移 覆岩断裂形态
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