Research on the Mechanism and Control Technology of Coal Wall Sloughing in the Ultra-Large Mining Height Working Face

Xuelong Li, Xinyuan Zhang, Wenlong Shen (), Qingdong Zeng (), Peng Chen (), Qizhi Qin and Zhen Li
Additional contact information
Xuelong Li: State Key Laboratory of Mining Disaster Prevention and Control, College of Energy and Mining Engineering, Shandong University of Science and Technology, Qingdao 266590, China
Xinyuan Zhang: State Key Laboratory of Mining Disaster Prevention and Control, College of Energy and Mining Engineering, Shandong University of Science and Technology, Qingdao 266590, China
Wenlong Shen: State and Local Joint Engineering Laboratory for Gas Drainage & Ground Control of Deep Mines, School of Energy Science and Engineering, Henan Polytechnic University, Jiaozuo 454000, China
Qingdong Zeng: State Key Laboratory of Mining Disaster Prevention and Control, College of Energy and Mining Engineering, Shandong University of Science and Technology, Qingdao 266590, China
Peng Chen: School of Mine Safety, North China Institute of Science and Technology, Langfang 101601, China
Qizhi Qin: Shandong Energy Group Co., Ltd., Jinan 250014, China
Zhen Li: State Key Laboratory of Mining Disaster Prevention and Control, College of Energy and Mining Engineering, Shandong University of Science and Technology, Qingdao 266590, China

IJERPH, 2023, vol. 20, issue 1, 1-17

Abstract: One of the primary factors affecting safe and effective mining in fully mechanized mining faces with large mining heights is coal wall sloughing. This paper establishes the mechanical model of the coal wall and uses the deflection theory for the mechanics of materials to find the maximum point of the deflection of the coal wall, which is the most easily deformed and damaged during the mining process, based on the mining production conditions of the 12-2up108 working face in the Jinjitan Coal Mine. In order to simulate the characteristics of the coal wall in the large mining height working face at various mining heights, the FLAC-3D numerical method was used. The stability of the mining area was assessed in conjunction with the multi-factor fuzzy comprehensive evaluation mathematical model, and the corresponding control of the coal wall was suggested. The study demonstrates that: (1) The working surface at Jinjitan Coal Mine 112-2up108 is a typical drum-out sloughing. The coal wall is most likely to sustain damage at the point where it contacts the roof when the frictional resistance between the coal seam and the roof and floor is less than the uniform load, and at 0.578 times the mining height when the frictional resistance between the coal seam and the roof and floor is greater than the uniform load. (2) In the working face with a large mining height, mining height of the coal wall is one of the significant influencing factors. With increasing mining height, the coal wall’s height also rises nonlinearly, as does the depth of the coal wall in the working face with the large mining height. The growth is linear. The coal wall’s maximum deflection value point moves up and the slab’s height significantly increases when the mining height exceeds 7.5 m. (3) The Jinjitan Coal Mine should be supported by a pressurized and enhanced composite support bracket with a support force greater than 0.245 MPa and a support plate of 3500 mm because it belongs to a Class I stable coal wall, according to a thorough evaluation of a multi-factor fuzzy mathematical model. The working face’s mining pressure is continuously and dynamically monitored, and the stress is released in a timely manner to prevent the occurrence of dynamic disasters.

Keywords: ultra-large mining height; coal wall sloughing; numerical simulation; stability; control technology (search for similar items in EconPapers)
JEL-codes: I I1 I3 Q Q5 (search for similar items in EconPapers)
Date: 2023
References: View references in EconPapers View complete reference list from CitEc
Citations: View citations in EconPapers (7)

Downloads: (external link)
https://www.mdpi.com/1660-4601/20/1/868/pdf (application/pdf)
https://www.mdpi.com/1660-4601/20/1/868/ (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:gam:jijerp:v:20:y:2023:i:1:p:868-:d:1023469

Access Statistics for this article

IJERPH is currently edited by Ms. Jenna Liu

More articles in IJERPH from MDPI
Bibliographic data for series maintained by MDPI Indexing Manager ().