Safe and efficient mining technology for high (over 6 m) rib pillars in inclined and flat longwalls within sheet-like ore bodies

A safe an efficient method is developed for mining pillars over 6 m high in inclined longwalls without the people presence in the mined-out void, with the preliminary cutting-off of the pillars from the roof, and with the orderly caving of the overlying rocks over the whole area of a longwall. In this method, a lateral inclined haulage drift is driven in the upslope direction of the longwall. This drift is connected with a set of lateral scraper drifts of a small cross-section, driven along each row of rib pillars. Broken ore is scraped along these scraper drifts to the inclined haulage drift; then, broken ore is displaced by a manmade rock–mud gravity flow downward to an ore pocket on the haulage level. A safe method is developed for mining high (over 6 m) pillars in flat-lying longwalls, which allows high-rate displacement of broken ore from under an overhang, along a shortest path, to an empty site behind the nearest pillars of the neighboring row. This can appreciably shorten stay of remote-control loading machines in the hazardous zone under the overhang, and can enable fast formation of a temporal ore storage in a safe place. Caving of pillars and loading of broken ore is carried out strictly within a caving pitch of immediate roof rocks, equal to the width of square pillar pattern; therefore, the overhang within this pitch is broken by controlled blasting in long and large-diameter holes pre-drilled through the pillar to the roof from the surface of the temporal ore storage. 

Volkov A. P., Gabbasov S. G., Baitov Zh. K., Yegemberdiyev R. I., Vasin K. A. Safe and efficient mining technology for high (over 6 m) rib pillars in inclined and flat longwalls within sheet-like ore bodies. MIAB. Mining Inf. Anal. Bull. 2026;(6):34-50. [In Russ]. DOI: 10.25018/0236_1493_2026_6_0_34.

The study is supported by the Ministry of Industry and Construction of the Republic of Kazakhstan within the framework of 2024–2026 targeted research funding, Project BR23991563: Creation of Innovative Resource-Saving Technologies for Mining and Integrated Processing of Mineral Resources and Mine Waste.

A.P. Volkov¹, Cand. Sci. (Eng.), Head of Laboratory, e-mail: apv51@mail.ru, ORCID ID: 0009-0008-6724-2537,
S.G. Gabbasov, Cand. Sci. (Eng.), Senior Lecturer, S. Seifullin Kazakh Agrotechnical Research University, Astana, 010000, Republic of Kazakhstan, e-mail: gabbasov57@bk.ru, ORCID ID: 0009-0006-9490-5813,
Zh.K. Baitov, Director, Elaman Invest LLP, Astana, 010000, Republic of Kazakhstan, e-mail: bz_elaman@mail.ru, ORCID ID: 0009-0001-3371-1883,
R.I. Yegemberdiyev¹, PhD, Researcher, e-mail: ryegemberdiyev@borusan.com, ORCID ID: 0009-0006-5330-9644,
K.A. Vasin¹, Postdoctoral Researcher, Senior Researcher, e-mail: kvas2500@mail.ru, ORCID ID: 0000-0002-4257-2061,
¹ National Center for Complex Processing of Mineral Raw Materials of the Republic of Kazakhstan, D.A. Kunaev Institute of Mining, Almaty, 050046, Republic of Kazakhstan,

K.A. Vasin, e-mail: kvas2500@mail.ru.

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