Gorbachev Kuzbass State Technical University, Kemerovo, Russia:

A. A. Krechetov, Associate Professor, Candidate of Engineering Sciences, krechetovaa@kuzstu.ru

A lot of scientific efforts are aimed at improving efficiency of rock bolting with friction rock stabilizers nowadays. One of the ways in this field is the use of a friction rock stabilizer with a W-shaped crosssection, designed by OKS Company. The use of this friction rock stabilizer type allows increasing the capacity of the roof support without the use of any additional materials and the need to perform additional operations. The paper presents the results of evaluating the maximum allowable loads, the stress–strain behavior and the spacer force when installing friction rock stabilizers in boreholes with the most common C-shaped cross-section with a wall thickness of 3 mm and with a W-shaped cross-section with a wall thickness of 2 mm, 2.5 mm and 3 mm. It is shown that, all other conditions being equal, the bearing capacity of the friction rock stabilizer with the W-shaped cross-section and the wall thickness of 2 mm, 2.5 mm and 3 mm is 1.6, 2 and 3.6 times greater than the load-bearing capacity of the stabilizer with the C-shaped cross-section and the wall thicknesses of 3 mm, respectively. It is proposed to use the ratio of the created spacer force to the mass of the stabilizer to assess the section effectiveness from the point of view of metal consumption. For the C-profile friction rock stabilizer with the wall thickness of 3 mm, this value is 57 kN/kg, for the W-profile friction rock stabilizer, this value is 109 kN/kg, 114 kN/kg and 157 kN/kg when its wall thickness is 2 mm, 2.5 mm and 3 mm, respectively.

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