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Longwall Mining an overview ScienceDirect Topics. longwall mining Mining. a mining method in which very long rectangular blocks of coal are defined during the development stage of the mine and then extracted in a single continuous operation by an automated cutting head moving parallel to the coal face.When the coal is cut, the working area is protected by a movable, powered roof support system.
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Abstract The paper presents an innovative numerical approach to simulate progressive caving of strata above a longwall coal mining panel. A proposed Trigon logic is incorporated within UDEC to successfully capture the progressive caving of strata which is characterized by
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2019-9-12 Longwall mining is a widely used underground mining method for the extraction of relatively thick, sub-horizontal and uniform coal seams. After mining of the coal seam, the panel roof strata above the mined-out area or goaf will be destressed.
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DOI: 10.1016/J.COMPGEO.2013.09.020 Corpus ID: 102328769. Evaluation of coal longwall caving characteristics using an innovative UDEC Trigon approach @article{Gao2014EvaluationOC, title={Evaluation of coal longwall caving characteristics using an innovative UDEC Trigon approach}, author={Fuqiang Gao and D. Stead and J. Coggan}, journal={Computers and Geotechnics},
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DOI: 10.1016/J.COMPGEO.2013.09.020 Corpus ID: 102328769. Evaluation of coal longwall caving characteristics using an innovative UDEC Trigon approach @article{Gao2014EvaluationOC, title={Evaluation of coal longwall caving characteristics using an innovative UDEC Trigon approach}, author={F. Gao and D. Stead and J. Coggan}, journal={Computers and Geotechnics}, year={2014},
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2015-1-4 The Tabas coal deposit includes three mineable seams (C1, B1, and B2). The C1 seam is the most important coal seam in Tabas and is mined using a mechanized longwall retreat mining method. The thickness of the coal seam ranges from 1.8 to 2.2 m (average 2 m). The overburden depth varies from 100 to 600 m.
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2017-11-1 Longwall Top Coal Caving has been considered as one of the most effective technologies for the extraction of underground thick coal seams. A large number of studies on the applicability of Longwall Top Coal Caving into new mine sites have linked the success of its application to the geomechanical understanding of the cavability of the top coal.
Read More2018-3-1 Longwall mining was then performed stage by stage. In each stage, 50 mm-long coal was removed using an electric drill. Forty minutes was then waited before the next excavation was performed, according to the constant of time similarity. These corresponded to a longwall panel advance of 2 m in 4 h in reality. A total of 59 excavation stages were carried out day and night continuously.
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2014-9-27 A numerical roadway model was created based on a case study at the Zhangcun coal mine in China. Coal extraction using the longwall mining method was simulated in the model with calculation of the mining-induced stresses. The process of roadway squeezing under severe mining-induced stresses was realistically captured in the model.
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In LW 5302, the longwall top coal caving (LTCC) method was used to extract coal seam No. 3. The mining and caving heights of coal seam No. 3 were 3.9 and 6.2 m, respectively. In Figure 1, it can be seen that LW 5302 was 120 m wide by 754 m long. The northwest side was adjacent to the longwall face 5301 (LW 5301) gob. The longwall top coal caving method was also used in LW 5301 to extract coal
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DOI: 10.1016/J.COMPGEO.2013.09.020 Corpus ID: 102328769. Evaluation of coal longwall caving characteristics using an innovative UDEC Trigon approach @article{Gao2014EvaluationOC, title={Evaluation of coal longwall caving characteristics using an innovative UDEC Trigon approach}, author={Fuqiang Gao and D. Stead and J. Coggan}, journal={Computers and Geotechnics},
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2015-1-4 Extraction of the coal seam causes stress redistribution around the mined panel in longwall mining. The weight of bridging strata and strata that cantilevers over the destressed zone is shifted to adjacent gates, pillars, and abutments surrounding the longwall panel. Thus, knowledge of the mining-induced stress is very important to enable accurate design of gate supports and pillar dimensions ...
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The paper presents an innovative numerical approach to simulate progressive caving of strata above a longwall coal mining panel. A proposed Trigon logic is incorporated within UDEC to successfully capture the progressive caving of strata which is characterized
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Coal is the major energy source in China. It is reported that, in 2012, coal consumption has reached 1873.3 million tonnes of oil equivalent, which accounts for 68% of the total energy consumption in China . To extract the coal seams from the subsurface, longwall mining is widely used because of its efficiency.
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There are three mineable coal seams in the Xinhe coal mine. The targeted longwall face 5302 (LW5302), as shown in Figure 1, was selected for this study. In LW 5302, the longwall top coal caving (LTCC) method was used to extract coal seam No. 3. The mining and caving heights of coal seam No. 3 were 3.9 and 6.2 m, respectively.
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2018-8-8 Floor heave in longwall gateroads is a severe issue that affects mining safety and efficiency. Researchers, however, have limited understanding on the floor heave mechanism because the
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2017-4-25 Preventing water seepage and inrush into mines where close multiple-seam longwall mining is practiced is a challenging issue in the coal-rich Ordos region, China. To better protect surface (or ground) water and safely extract coal from seams beneath an aquifer, it is necessary to determine the height of the mining-induced fractured zone in the overburden strata.
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Mining of the coal seam adjacent to the extracted coal panel is widely practiced in China to improve coal resource recovery rates, but the energy change associated with longwall mining may present a new risk to ground stability and gateroad failure. To understand the energy change effectively, a meticulously validated numerical
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Whittaker et al used gravity loaded sand–plaster mixtures to simulate longwall coal mining and induced subsidence under various conditions (Whittaker et al 1990). Xie et al used a mixture of fine sand, gypsum, lime and loess of different portions to simulate a fully mechanized top-coal caving panel and different rock layers (Xie et al 2009 ).
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2016-9-21 Stead D, Eberhardt E (1997) Developments in the analysis of footwall slopes in surface coal mining. Eng Geol 46(1):41–61. Article Google Scholar Sun XY, Xia YC, Bai HM (2007) Numerical simulation of control of fold structures on mining subsidence. J China Coal
Read More2015-1-4 Extraction of the coal seam causes stress redistribution around the mined panel in longwall mining. The weight of bridging strata and strata that cantilevers over the destressed zone is shifted to adjacent gates, pillars, and abutments surrounding the longwall panel. Thus, knowledge of the mining-induced stress is very important to enable accurate design of gate supports and pillar dimensions ...
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open longwall mining, open longwall working offener Strebbau m, versatzloser Strebbau, Strebbau ohne Bergeversatz
Read MoreCoal is the major energy source in China. It is reported that, in 2012, coal consumption has reached 1873.3 million tonnes of oil equivalent, which accounts for 68% of the total energy consumption in China . To extract the coal seams from the subsurface, longwall mining is widely used because of its efficiency.
Read More2018-8-8 Floor heave in longwall gateroads is a severe issue that affects mining safety and efficiency. Researchers, however, have limited understanding on the floor heave mechanism because the
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2009-10-1 A HIGH level of training with a package specifically designed for longwall operators is expected to hold Australia's newest longwall mine, Carborough Downs, in good...
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2020-12-31 During longwall mining, the area directly upon the longwall opening undergoes a deformation and tends to cave towards the face rear as a result of coal production and face advance. Therefore, the rock mass in this area has weaker mechanical properties than the
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2019-5-9 In the Rembas mine pits for coal exploitation, the low-productive pillar mining methods are used. During the eighties of the last century in some pits, the mechanized longwall mining method was applied, but the expensive equipment and complex natural-geological conditions in the area Resava-Moravian coal basin restrict application of this metod ...
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2007-3-16 5. Open Pit Mining / Mines a del ouvert Numerical modelling of buckling and ploughing slope instability in surface coal mining 176 E. Eberhardt D. Stead Interpretation of non-structural slope failure in open-pit mining - A numerical 186 modelling approach CM. Tsomondo H.S. Mitri Toppling and sliding of blocks under dynamic loading 198 M.Y ...
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Assessment of the roof behavior in longwall gob and estimation of the occurrence of caving and fracturing zones above mined panels are the main factors used in evaluating abutment stresses, ground subsidence, face support and adjacent structures design. The combined height of caving and fracturing zones is taken as equivalent to the height of destressed zone (HDZ) in this study.
Read MoreThe coal-bearing section has a total thickness of 343 m containing three minable seams. The mining seam at the LW working panel is 2 −2, which has an average thickness of 3.2 m and an average dip angle of 4° ranging from 3° to 7°. The LW mechanized retreat full caving mining method is
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الصين -تشنغ تشو -المنطقة الوطنية للتنمية الصناعية للتكنولوجيا المتطورة، جادة العلوم رقم 169.
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