Author 1:
Name & Surname: Svyatetsky V. S.
Company: ARMZ Uranium Holding Co. (Moscow, Russia)
Work Position: First Deputy Director General—Chief Operating Officer

Author 2:
Name & Surname: Kuzmin E. V.
Company: VNIPIpromtekhnologii JSC (Moscow, Russia)
Work Position: Head of laboratory
Scientific Degree: Professor, Doctor of Engineering Sciences
Contacts: e-mail: kuzmin.E.V@vnipipt.ru

Author 3:
Name & Surname: Starodumov A. V.
Company: VNIPIpromtekhnologii JSC (Moscow, Russia)
Work Position: Director

Author 4:
Name & Surname: Velichko D. V.
Company: Russian State Geological Prospecting University (Moscow, Russia)
Work Position: Senior Lecturer

The useful contribution to the work is made by A. M. Ioffe, Candidate of Engineering Sciences, Principal Researcher, VNIPIpromtekhnologii JSC.

In terms of the ground and mine-technical conditions in the Streltsovsk uranium ore field, the authors substantiate applicability of high-productive room and pillar mining with remote-control load-haul-dumpers to transport broken ore from rooms with unstable roof and walls pre-reinforced with cable bolts and cement grouting. The article presents flow charts, parameters and structural elements of pre-reinforcement (before ore breaking) of adjacent enclosing rock mass with the stability category II–IV estimated by the enclosing rock subsidence at the interface with the exposed mined out void (VNIMI classification). In terms of two extraction blocks of the Argun deposit, the authors describe studies aimed at forecasting of geomechanical parameters of rocks and estimating stability of exposures in stopes using advanced program products (IT technologies) and FEM modeling. From the research data, it is proved that pre-reinforcement of the adjacent enclosing rocks with the stability category III allows the rock mass reclassification as the stability category II, which excludes hazardous rockfalls by setting lower standards for strains and displacements at the interface between stopes and rock mass. Thus, applicability of efficient room and pillar method to uranium ore extraction with pre-reinforcement of unstable adjacent rock mass has been substantiated.

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