A study on the bearing effect of pier column backfilling in the goaf of a thin coal seam

Aimed at the specific geological conditions of 7# thin coal seam in Liuquan Mine, this paper used the methods of numerical calculation and theoretical analysis to determine the reasonable technological parameters of high-grade conventional mining face. The numerical simulation software of UDEC (Universal Distinct Element Code) was used to contrast and analyse the characteristics of surrounding rock stress distribution and overlying rock horizontal displacement under the condition of different length of coalface, then it was indicated that the surrounding rock deformation was less when length of coalface was 110 m which was advantageous for roof control; according to the conditions of roof and floor, the roof support strength was being calculated systematically to determine the row space of props being 700×1200 mm; the main equipments of coalface was assorted, and reasonable work manner in coalface and gob processing measure was put forward, which provided guidance for efficient mining in thin coal seam.

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Study on Numerical Simulation of Short-Distance Extremely Thin Coal Seam Mining Based on FLAC3D

Mine Engineering ◽

10.12677/me.2019.71011 ◽

2019 ◽

Vol 07 (01) ◽

pp. 69-75

Author(s):

松杨

Keyword(s):

Numerical Simulation ◽

Coal Seam ◽

Short Distance ◽

Thin Coal Seam ◽

Seam Mining

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New Techniques and Technologies in Thin Coal Seam Exploitation

10.1201/b11749 ◽

2011 ◽

Cited By ~ 1

Keyword(s):

Coal Seam ◽

New Techniques ◽

Thin Coal Seam

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Research on Kinematics Joint Type Mobile Robot Platform for Thin Coal Seam Inspection

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.651-653.818 ◽

2014 ◽

Vol 651-653 ◽

pp. 818-821 ◽

Cited By ~ 1

Author(s):

De Yong Shang ◽

Jian Wei Zhao ◽

Na Liu ◽

Yun Long Zhang ◽

Xun Fan

Keyword(s):

Coal Seam ◽

Theoretical Foundation ◽

Harsh Environments ◽

Motion Platform ◽

Inspection Robot ◽

Thin Coal Seam ◽

Inspection Work ◽

Narrow Space ◽

Thin Seam ◽

Robot Platform

Due to the high labor intensity of the maintenance workers, the narrow space and harsh environments in mining process of thin coal seam, an inspection robot to adapt to the thin seam environment instead of workers for the inspection work is urgently need . In this paper, we research on a bionic joint type inspection robot motion platform in thin coal seam, and study the kinematics analysis, which is a theoretical foundation for this kind of the robot platform control.

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Study on Technology of Mechanized Mining in Extremely Thin Coal Seam

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.962-965.980 ◽

2014 ◽

Vol 962-965 ◽

pp. 980-983

Author(s):

Wei Guang Li ◽

Chao Li ◽

Ke Li Chen

Keyword(s):

Coal Seam ◽

Economic Effects ◽

Coal Production ◽

Thin Coal Seam ◽

Organization And Management ◽

Working Space ◽

Serious Injury ◽

Mining Face ◽

Thin Seam ◽

Small Working

The reserve proportion of thin coal seam in Sichuan Province is as high as 60%, of which the extremely thin coal seam mines with the coal thickness less than 0.6m take up 34.3% in the total number of Sichuan coal mines. Exploiting the extremely thin seam called Xiayuantan in Laoyingyan Coalmine confronts so many problems, such as small working space in coalface, difficulty in transporting, high labor intensity, poor production, and low stoping efficiency. Aiming at these problems, this paper puts forward the conventionally-mechanized coal winning technology, investigates the selection, matching, organization and management of equipment in mechanized mining face. Moreover, it demonstrates the rationality of associated equipment selection, that is, MG100-TP off-pan shearer is suitable for exploiting the extremely thin coal seam mechanically. There are less workers in the mechanized mining face, the raw coal production and the stoping efficiency have been enhanced, the roof condition of workface has been improved,serious injury and any other more serious accidents have been completely eradicated. The technology obtains remarkable economic effects and safety benefits.

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Hydraulic Fracture Propagation and Permeability Evolution in the Composite Thin Coal Seam

Geofluids ◽

10.1155/2021/5576328 ◽

2021 ◽

Vol 2021 ◽

pp. 1-10

Author(s):

Shenglong Liu ◽

Bingxiang Huang ◽

Weiyong Lu ◽

Haoze Li ◽

Ding Li ◽

...

Keyword(s):

Coal Seam ◽

Hydraulic Fracturing ◽

Hydraulic Fracture ◽

Water Pressure ◽

Fracture Propagation ◽

Injection Pressure ◽

Unstable Fracture ◽

Permeability Evolution ◽

Thin Coal Seam ◽

Hf Propagation

Hydraulic fracturing can improve the permeability of composite thin coal seam. Recently, characterizing hydraulic fracture (HF) propagation inside the coal seam and evaluating the permeability enhancement with HF extension remain challenging and crucial. In this work, based on the geological characteristics of the coal seam in a coal mine of the southwest China, the RFPA2D-Flow software is employed to simulate the HF propagation and its permeability-increasing effect in the composite thin coal seam, and a couple of outcomes were obtained. (1) Continuous propagation of the hydraulic microcrack-band is the prominent characteristic of HF propagation. With the increment of the injection-water pressure, HF generation in the composite thin coal seam can be divided into three stages: stress accumulation, stable fracture propagation, and unstable fracture propagation. (2) The hydraulic microcrack-band propagates continuously driven by the fluid-injection pressure. The microcrack-band not only cracks the coal seam but also fractures the gangue sandwiched between the coal seams. (3) The permeability in the composite thin coal seam increases significantly with the propagation of hydraulic microcrack-band. The permeability increases by 1~2 magnitudes after hydraulic fracturing. This study provides references to the field applications of hydraulic fracturing in the composite thin coal seam, such as optimizing hydraulic fracturing parameters, improving gas drainage, and safe-efficient mining.

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New advances in automatic shearer cutting technology for thin seams in Chinese underground coal mines

Energy Exploration & Exploitation ◽

10.1177/01445987211052060 ◽

2021 ◽

pp. 014459872110520

Author(s):

Wang Chen ◽

Zhou Jie

Keyword(s):

Coal Seam ◽

Production Efficiency ◽

Geological Structures ◽

Mining Technology ◽

Thin Coal Seam ◽

Labour Intensity ◽

Underground Coal Mines ◽

Coal Rock ◽

Improve Production Efficiency ◽

The Ideal

Automatic mining technology is the ideal path and the inevitable way to improve production efficiency, reduce labour intensity and ensure safety for thin coal seam. Recently, while automatic mining technology is increasingly applied in China for thin seams, the corresponding automatic cutting technology has made new advances. Among them, mnemonic cutting technology has been fruitful industrial tested with suitable conditions. Simultaneously, another one called cutting trace pre-set technology of the shearer has been put forward. Using this method, the cutting trace in the area with coal thickness changed and geological structures can be preset. What's more, self-adaptive regulation strategy of cutting trace based on coal-rock recognition by monitoring current of cutting motor was discussed. Then, the main problems and development trends of automatic mining in China was also proposed.

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