Justification of the longwall panel entries support technology when mining gently inclined coal seams at large depths

The analysis of domestic and foreign experience in ensuring stability of the panel entries, outlining the longwall panels in coal mines is presented. It is shown that with increasing the depth of mining operations to provide the entries stability by leaving the pillars there is a need to increase the size of the pillars, thus increasing the operating losses of coal. The pillars create a stress shadow zones, which complicates the mining of adjacent seams, and may also create the hazards of rockbursts. The article considers the technologies of panel entries maintenance at pillarless longwall mining system, including the choice of the form and sizes of the cross-section of panel entries, parameters of the support pattern, support reinforcement in the zone of the longwall face abutment pressure, parameters of the supporting constructions on the border with the gob area. Separately, the experience of Chinese coal mines in applying pillarless mining system for mining thick seams with top coal caving is described. The effectiveness of using steel pipes filled with concrete as supporting constructions at the border with the gob area is noted. With regard to the geological and mining-technical conditions of the mines of the Eastern Donbass, the possibilities of using the various supporting constructions to maintain the longwall entries behind the longwall are considered. It is shown, that for the thin seams, where panel entries is developing with the cut-off of the surrounding rock layers, the application of the supporting constructions, which includes the rock from the cut-off, is the most perspective way of supporting. The analysis of the possible technologies of erection of the supporting constructions is made, the directions of improvement of technological schemes of entries development and maintaining the for the conditions of the mines of the Eastern Donbass are defined.

Kazanin O. I., Sidorenko A. A., Evsiukova A. A., Zilu Liu Justification of the longwall panel entries support technology when mining gently inclined coal seams at large depths. MIAB. Mining Inf. Anal. Bull. 2023;(9-1):5-21. [In Russ]. DOI: 10.25018/0236_1493_ 2023_91_0_5.

O.I. Kazanin¹, Dr. Sci. (Eng.), Professor of Russian Academy of Sciences, e-mail: Kazanin_OI@pers.spmi.ru, ORCID ID: 0000-0001-9663-6713,
A.A. Sidorenko¹, Cand. Sci. (Eng.), Assistant Professor, e-mail sidorenko_aa@pers.spmi.ru, ORCID ID: 0000-0003-4224-193X,
A.A. Evsiukova¹, Graduate Student, e-mail: alinka_evsyukova@mail.ru, ORCID ID: 0000-0003-3513-7587,
Zilu Liu¹, Graduate Student, e-mail liuzl@cumt.edu.cn, ORCID ID: 0000-0001-5738-9254,
¹ Saint-Petersburg Mining University, 199106, Saint-Petersburg, Russia.

O.I. Kazanin, e-mail: Kazanin_OI@pers.spmi.ru.

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