Longwall top coal caving (LTCC) technology is one of the effective methods for extracting thick and extra-thick coal seams. Since it is introduced into China in 1982, LTCC has gained a lot of achievements and experience not only in caving technology and equipment but also in the drawing theory after 40 years of development, …
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Longwall top coal caving (LTCC) is a highly efficient underground mining method that has recently been introduced and modified, and is now being used in underground coal mines in China. The major difference between LTCC and traditional longwall methods is that LTCC extracts caved coal from behind shields as well as from …
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A 3D particle-based numerical approach to simulate the longwall top coal caving (LTCC) process was proposed, which for the first time the effect of continuous support advance and the face-end ...
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Based on the engineering background of gob-side entry retaining in fully-mechanized longwall with top coal caving (GER-FLTC) on N2105 working face of Yuwu coal mine, by adopting the …
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Top coal caving technologies is not a novelty. The first experimental tests of top coal caving were undertaken well before engineering of longwall mining systems and hydraulically-powered shield-type roof supports. In the USSR experiments with top coal caving in the supported area of roadways were initiated in the 1930s [1].
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Semantic Scholar extracted view of "Field and numerical investigations of gateroad system failure induced by hard roofs in a longwall top coal caving face" by Qingsheng Bai et al. Skip to search form Skip to main content Skip to account menu. Semantic Scholar's Logo. Search 221,098,730 papers from all fields of science ...
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The changing mining conditions during longwall top coal caving mining (LTCC) were extracted from a coupled numerical model to provide statistically sufficient data for probabilistic analysis. ... Dynamically updated system feedback from the numerical model was fed into the framework to represent the current stress state in retreating …
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This review details the state of the art in research on top coal drawing mechanisms in Longwall top coal caving (LTCC) by examining the relevant literature …
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It is assumed that the upper bound of applying SPL method as a mechanized system in thick coal seams is about 6m. ... Keywords Longwall top coal caving (LTCC) Á Top coal drawing Á Top coal ...
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Using longwall top coal caving (LTCC) in an extra-thick seam, many problems appear, such as large broken top coal blocks, frequent arch formation in the drawing process, poor balance of drawing ...
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Abstract In this study, the finite difference method (FDM) coupled with a discrete fracture network (DFN) was utilized to analyze longwall top coal caving (LTCC) behaviors. The integrated FDM–DFN model enabled the influence of …
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Both longwall systems are designed for longwall top coal caving (LTCC) in a coal seam with an average thickness of 25 meters (82 feet). ... In addition to the conventional roof supports ...
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"Reference 11 showed the effect of discontinuities on the stresses on the pillar in the longwall top coal caving ... and design of LTCC mining operation systems with complex mining conditions 5 ...
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Abstract -Longwall top coal caving (LTCC) techniques has been employed in favourable geological conditions widely in China since the mid-80s and in Australia recently. With …
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Longwall Top Coal Caving (LTCC) is a modified longwall mining method for efficient extraction of the thick coal seams. The major difference between LTCC and the traditional longwall method is the extraction of the caved coal from behind the shields as well as the sheared face (Fig. 1).The method has been widely implemented by the …
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An extraction method for deep-seated thick seam deposits by underground mining with high resource recovery has remained a great challenge for Indian mining engineers, whereas the longwall top coal caving (LTCC) method has evolved as an effective method for various geo mining conditions in China and other counties. The …
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A number of mechanical models of longwall face stability were developed in previous analytical studies. Frith [] proposed a conceptual model that was composed of a vertically cleated coal seam, a horizontally bedded immediate roof loaded by overburden strata, and shield support (Fig. 1).Based on the theory of Euler buckling (in particular, …
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For studying the strata behavior due to multi-slicing top coal caving longwall mining along-the-strike direction in steeply dipping extra thick coal seams, the shield support pressures of the upper and lower slices of panel 37220 in Dongxia Coal Mine were monitored using the KJ513 dynamic monitoring system. The set up rooms adopted the ...
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The optimization of top coal caving technology is an efficient method to improve the recovery ratio in longwall top coal caving (LTCC). In extrathick coal …
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Request PDF | Field and numerical investigations of gateroad system failure induced by hard roofs in a longwall top coal caving face | In longwall mining, hard roofs located immediately above the ...
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The development of top coal caving technology has entered a mature stage [1,2,3,4].As China's coal mining center gradually shifts to the northwest, the characteristics of coal thickness have gradually changed from thick 3.5–8 m to extrathick 8–30 m [].With changes in coal seam occurrence conditions, research on top coal …
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The re-mined face using top coal caving system is the most applicable method for recovering the remaining reserves of a previous partially-mined thick coal seam. However, this mining method may ...
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In this study, the finite difference method (FDM) coupled with a discrete fracture network (DFN) was utilized to analyze longwall top coal caving (LTCC) …
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On the basis of normal longwall system, Longwall Top Coal Caving (LTCC) method has been developed to extract thick coal seams of 5–12 m at one pass of the shearer (coal cutting machine). The general …
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Longwall Top Coal Caving (LTCC) is an enhanced form of the conventional longwall recovery system, whereby a rear Armoured Face Conveyor (AFC) (refer to Figure 3) is …
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Based on the relevant literature over the last two decades (2000–2020), Fig. 2 shows the key issues, questions, and expected goals in research on top coal drawing in LTCC. The research framework that has largely been …
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Abstract Longwall mechanized top coal caving mining (LMTCCM) in extra-thick coal seams has its own characteristics. The law of mining pressure and overlying …
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A New Gob-Side Entry Layout for Longwall Top Coal Caving ... Fortunately, case point uses mustabe considered when a system coal mine use the NGE approach. case coal mine two-wing longwall as plans showntoin Figure 30. The panelsFortunately, are mined this in numbered study coal mine uses a two-wing longwall system as shown in Figure …
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Dynamic sublevel caving technology (DSCT) proposed by the researchers is one of effective methods to solve the problems of low top coal recovery, poor drawing balance and support stability in longwall top coal caving (LTCC) with large dip angle. To investigate the reasonable number of supports in a sublevel (N) and the top coal …
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Longwall Top Coal Caving (LTCC) is a modified longwall mining method for efficient extraction of the thick coal seams. The major difference between LTCC and the traditional longwall method is the extraction of the caved coal from behind the shields as well as the sheared face (Fig. 1).
WhatsApp: +86 18221755073