Cooperative mining technology and strata control of close coal seams and overlying coal pillars
Mining of close coal seams envisages reservation of a large number of section coal pillars of a total width ranging from 30 to 40 m. This results in an enormous waste of coal resources and risks of spontaneous combustion, instability, and damage to the remaining coal pillars. This study attempts to...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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Elsevier
2023-07-01
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| Series: | Alexandria Engineering Journal |
| Subjects: | |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S1110016823003526 |
| _version_ | 1797803971854729216 |
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| author | Sun Qiang Gao Jialiang Yang Feng Bai Ruhong |
| author_facet | Sun Qiang Gao Jialiang Yang Feng Bai Ruhong |
| author_sort | Sun Qiang |
| collection | DOAJ |
| description | Mining of close coal seams envisages reservation of a large number of section coal pillars of a total width ranging from 30 to 40 m. This results in an enormous waste of coal resources and risks of spontaneous combustion, instability, and damage to the remaining coal pillars. This study attempts to mitigate the above problems via the proposed cooperative mining technical method for close seams and overlying coal pillars. It expounds on the technical principles, the required mining equipment, technology, and the system layout, and analyzes the key influencing factors of strata control. Using the numerical simulation via FLAC3D and PFC2D commercial software packages, the effect of horizontal distance between the lower coal seam roadway and the overlying coal pillar (i.e., spacing) on the surrounding rock control and rational layout of the roadway is studied. The mechanism of the overlying coal pillar width effect on the ground pressure of the stope and coal pillar recovery rate is clarified. The engineering case study shows that when the horizontal spacing was increased from 0 to 15 m, the surrounding rock deformation, surrounding rock stress peak value, and plastic zone area of the roadway decreased significantly. When the coal pillar width in the overlying section was increased from 25 to 40 m, the peak values of lateral and advance bearing stresses in the stope dropped by 21 and 12 MPa, respectively. Besides, the ground pressure driving strength of the stope was significantly reduced, and the recovery rates of the overlying coal pillar and rock between the close coal seams were increased by 7.45 and 4.29%, respectively. Combined with the top coal pillar drawing pattern, optimization concepts and their realization methods were proposed. |
| first_indexed | 2024-03-13T05:29:04Z |
| format | Article |
| id | doaj.art-0e9a053e04f24808b3ca4e3c46063f50 |
| institution | Directory Open Access Journal |
| issn | 1110-0168 |
| language | English |
| last_indexed | 2024-03-13T05:29:04Z |
| publishDate | 2023-07-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Alexandria Engineering Journal |
| spelling | doaj.art-0e9a053e04f24808b3ca4e3c46063f502023-06-15T04:54:23ZengElsevierAlexandria Engineering Journal1110-01682023-07-0173473485Cooperative mining technology and strata control of close coal seams and overlying coal pillarsSun Qiang0Gao Jialiang1Yang Feng2Bai Ruhong3School of Mines, China University of Mining & Technology, Xuzhou 221116, China; Shaanxi Yulin Energy Group Yushen Coal Power Co. Ltd, Yulin, Shaanxi, China; Corresponding author at: School of Mines, China University of Mining & Technology, Xuzhou 221116, China.School of Mines, China University of Mining & Technology, Xuzhou 221116, ChinaSchool of Mines, China University of Mining & Technology, Xuzhou 221116, ChinaShaanxi Yulin Energy Group Yushen Coal Power Co. Ltd, Yulin, Shaanxi, ChinaMining of close coal seams envisages reservation of a large number of section coal pillars of a total width ranging from 30 to 40 m. This results in an enormous waste of coal resources and risks of spontaneous combustion, instability, and damage to the remaining coal pillars. This study attempts to mitigate the above problems via the proposed cooperative mining technical method for close seams and overlying coal pillars. It expounds on the technical principles, the required mining equipment, technology, and the system layout, and analyzes the key influencing factors of strata control. Using the numerical simulation via FLAC3D and PFC2D commercial software packages, the effect of horizontal distance between the lower coal seam roadway and the overlying coal pillar (i.e., spacing) on the surrounding rock control and rational layout of the roadway is studied. The mechanism of the overlying coal pillar width effect on the ground pressure of the stope and coal pillar recovery rate is clarified. The engineering case study shows that when the horizontal spacing was increased from 0 to 15 m, the surrounding rock deformation, surrounding rock stress peak value, and plastic zone area of the roadway decreased significantly. When the coal pillar width in the overlying section was increased from 25 to 40 m, the peak values of lateral and advance bearing stresses in the stope dropped by 21 and 12 MPa, respectively. Besides, the ground pressure driving strength of the stope was significantly reduced, and the recovery rates of the overlying coal pillar and rock between the close coal seams were increased by 7.45 and 4.29%, respectively. Combined with the top coal pillar drawing pattern, optimization concepts and their realization methods were proposed.http://www.sciencedirect.com/science/article/pii/S1110016823003526Close coal seamsSectional coal pillarStrata controlGround pressureCoal drawing rate |
| spellingShingle | Sun Qiang Gao Jialiang Yang Feng Bai Ruhong Cooperative mining technology and strata control of close coal seams and overlying coal pillars Alexandria Engineering Journal Close coal seams Sectional coal pillar Strata control Ground pressure Coal drawing rate |
| title | Cooperative mining technology and strata control of close coal seams and overlying coal pillars |
| title_full | Cooperative mining technology and strata control of close coal seams and overlying coal pillars |
| title_fullStr | Cooperative mining technology and strata control of close coal seams and overlying coal pillars |
| title_full_unstemmed | Cooperative mining technology and strata control of close coal seams and overlying coal pillars |
| title_short | Cooperative mining technology and strata control of close coal seams and overlying coal pillars |
| title_sort | cooperative mining technology and strata control of close coal seams and overlying coal pillars |
| topic | Close coal seams Sectional coal pillar Strata control Ground pressure Coal drawing rate |
| url | http://www.sciencedirect.com/science/article/pii/S1110016823003526 |
| work_keys_str_mv | AT sunqiang cooperativeminingtechnologyandstratacontrolofclosecoalseamsandoverlyingcoalpillars AT gaojialiang cooperativeminingtechnologyandstratacontrolofclosecoalseamsandoverlyingcoalpillars AT yangfeng cooperativeminingtechnologyandstratacontrolofclosecoalseamsandoverlyingcoalpillars AT bairuhong cooperativeminingtechnologyandstratacontrolofclosecoalseamsandoverlyingcoalpillars |