Author 1:
Name & Surname: Grechishkin P. V.
Company: Institute of Coal, Siberian Branch, Russian Academy of Sciences (Kemerovo, Russia)
Work Position: Researcher
Scientific Degree: Candidate of Engineering Sciences
Contacts: pv_grechishkin@mail.ru

Author 2:
Name & Surname: Pozolotin A. S.
Company: RANK 2 LTD (Kemerovo, Russia)
Work Position: Director for Long-Term Development
Scientific Degree: Candidate of Engineering Sciences

Author 3:
Name & Surname: Zayatdinov D. F.
Company: RANK 2 LTD (Kemerovo, Russia)
Work Position: Deputy Director of Long-Term Development

Author 4:
Name & Surname: Sharov V. N.
Company: AMK SHSU LTD (Kemerovo, Russia)
Work Position: Principal Engineer

A. A. Dudin ("RANK 2" JSC) has participated in this work.

Efficiency of two-level rock bolt support in wide-span roadways and at junctions in various ground and mine-technical conditions of Kuzbass mines is estimated. In terms of junctions of various purpose roadways, the authors discuss design and parameters of the two-level rock bolt support and its construction technology depending on physicomechanical properties of overlying rocks, their structure and stability, and dimension (area and span) of the junctions. It is highlighted that reliability and preset durability (life) of the two-level rockbolting is ensured by the primary rock bolting of disintegrated roof rocks in case of pressure arch and the secondary injection-grouted cable bolting of the reinforced roof rocks to fix them to adjacent stable rock mass. The well consistent estimates of the basic technical and economic performance of the conventional frame support and the two-level rock bolting of wide-span junctions show essential reduction in materials consumed, delivery and installation labor input and overall cost in case of the two-level rock bolting system.

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