Study on Coal Pillar Setting and Stability in Downward Mining Section of Close Distance Coal Seam
To investigate the reasonable width of a coal pillar in the downward mining section of close-distance coal seams, the stress state of any point below the residual coal pillar in the overlying goaf and the width of a small coal pillar were studied by theoretical calculation, numerical simulation, sim...
Saved in:
| Main Authors: | , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2024-10-01
|
| Series: | Energies |
| Subjects: | |
| Online Access: | https://www.mdpi.com/1996-1073/17/21/5441 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1850193015532945408 |
|---|---|
| author | Longpei Ma Chongyan Liu Guangming Zhao |
| author_facet | Longpei Ma Chongyan Liu Guangming Zhao |
| author_sort | Longpei Ma |
| collection | DOAJ |
| description | To investigate the reasonable width of a coal pillar in the downward mining section of close-distance coal seams, the stress state of any point below the residual coal pillar in the overlying goaf and the width of a small coal pillar were studied by theoretical calculation, numerical simulation, similar simulation and field monitoring. The findings indicate that the width range of the small coal pillar is 7.92~11.42 m. The 4-1 coal seam is in the stress reduction zone when it is more than 16.6 m horizontally from the border of the residual coal pillar above it. In addition, the peak stress is situated inside the elastic zone of the coal pillar and is lower than the coal pillar’s bearing limit when a small coal pillar of 8 m is maintained. With the help of distributed optical fiber monitoring to model the coal pillars’ stress distribution, it is found that 8 m simulated coal pillars have a certain bearing capacity. The practical findings demonstrate that the 8 m small coal pillar that was left on the site satisfies the demand, and the convergence of the roadway’s floor and roof, and its two sides fall within the controllable range. The findings of the study offer a reference for the location of a return air roadway and the width of section coal pillars in the downward mining of close-distance coal seams. |
| format | Article |
| id | doaj-art-3f4e023ef4b74f84938392f1a9c0323e |
| institution | OA Journals |
| issn | 1996-1073 |
| language | English |
| publishDate | 2024-10-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Energies |
| spelling | doaj-art-3f4e023ef4b74f84938392f1a9c0323e2025-08-20T02:14:22ZengMDPI AGEnergies1996-10732024-10-011721544110.3390/en17215441Study on Coal Pillar Setting and Stability in Downward Mining Section of Close Distance Coal SeamLongpei Ma0Chongyan Liu1Guangming Zhao2Joint National-Local Engineering Research Centre for Safe and Precise Coal Mining, Anhui University of Science and Technology, Huainan 232000, ChinaJoint National-Local Engineering Research Centre for Safe and Precise Coal Mining, Anhui University of Science and Technology, Huainan 232000, ChinaJoint National-Local Engineering Research Centre for Safe and Precise Coal Mining, Anhui University of Science and Technology, Huainan 232000, ChinaTo investigate the reasonable width of a coal pillar in the downward mining section of close-distance coal seams, the stress state of any point below the residual coal pillar in the overlying goaf and the width of a small coal pillar were studied by theoretical calculation, numerical simulation, similar simulation and field monitoring. The findings indicate that the width range of the small coal pillar is 7.92~11.42 m. The 4-1 coal seam is in the stress reduction zone when it is more than 16.6 m horizontally from the border of the residual coal pillar above it. In addition, the peak stress is situated inside the elastic zone of the coal pillar and is lower than the coal pillar’s bearing limit when a small coal pillar of 8 m is maintained. With the help of distributed optical fiber monitoring to model the coal pillars’ stress distribution, it is found that 8 m simulated coal pillars have a certain bearing capacity. The practical findings demonstrate that the 8 m small coal pillar that was left on the site satisfies the demand, and the convergence of the roadway’s floor and roof, and its two sides fall within the controllable range. The findings of the study offer a reference for the location of a return air roadway and the width of section coal pillars in the downward mining of close-distance coal seams.https://www.mdpi.com/1996-1073/17/21/5441close distance coal seamresidual coal pillarcoal pillar widthdistributed optical fiber monitoringstability of surrounding rock |
| spellingShingle | Longpei Ma Chongyan Liu Guangming Zhao Study on Coal Pillar Setting and Stability in Downward Mining Section of Close Distance Coal Seam Energies close distance coal seam residual coal pillar coal pillar width distributed optical fiber monitoring stability of surrounding rock |
| title | Study on Coal Pillar Setting and Stability in Downward Mining Section of Close Distance Coal Seam |
| title_full | Study on Coal Pillar Setting and Stability in Downward Mining Section of Close Distance Coal Seam |
| title_fullStr | Study on Coal Pillar Setting and Stability in Downward Mining Section of Close Distance Coal Seam |
| title_full_unstemmed | Study on Coal Pillar Setting and Stability in Downward Mining Section of Close Distance Coal Seam |
| title_short | Study on Coal Pillar Setting and Stability in Downward Mining Section of Close Distance Coal Seam |
| title_sort | study on coal pillar setting and stability in downward mining section of close distance coal seam |
| topic | close distance coal seam residual coal pillar coal pillar width distributed optical fiber monitoring stability of surrounding rock |
| url | https://www.mdpi.com/1996-1073/17/21/5441 |
| work_keys_str_mv | AT longpeima studyoncoalpillarsettingandstabilityindownwardminingsectionofclosedistancecoalseam AT chongyanliu studyoncoalpillarsettingandstabilityindownwardminingsectionofclosedistancecoalseam AT guangmingzhao studyoncoalpillarsettingandstabilityindownwardminingsectionofclosedistancecoalseam |