UralEnergoResurs, Ekaterinburg, Russia:
A. A. Zubkov, Deputy Director, Candidate of Engineering Sciences

Ural Branch, Russian Academy of Sciences, Russia:
A. V. Zubkov, Chief Researcher, Doctor of Engineering Sciences

Nosov Magnitogorsk State Technical University, Magnitogorsk, Russia:
I. M. Kutlubaev, Professor, Doctor of Engineering Sciences, ptmr74@mail.ru
V. V. Latkin, Post-Graduate Student

One of the modern methods of lining of mine workings is based on the use of friction rock stabilizers (FRS). Their application allows high degree of automation of the entire work process. As an anchor rod, a hollow cylinder with a longitudinal groove along its length is used. Due to the diff erence between its outer diameter and the diameter of the hole created by the frictional force, locking of the anchor from shifting is ensured. Functionality of the bolting is determined by its capacity to bear frictional load and by the type of the rod support assembly interacting with the baseplate. To increase the bearing capacity of the support unit, a new design solution is proposed. It is based on the creation of a system consisting of the support ring welded to the rod and the support of the lock formed during the installation process. In the conventional design of the supporting units of foreign manufacture, the external load gives rise to shear stresses in the weld. In the new technical solution developed and patented by the Russian company UralEnergoResurs, normal stresses additionally appear in the supporting lock. The experimental study of bearing capacity of the traditional design support unit TFA and new FRS has been carried out. It is found that the magnitude of the bearing axial force increases by 22–27% due to the lock support. The new key sample unit requires changing technology of roof bolting to provide correct sequence of operations performed. The article identifi es options for advanced technological solutions to strengthen mine exposures based on the design of roof bolting with FRS.
The authors acknowledge the participation of S. S. Neugomonov, Associate Professor, Candidate of Engineering Sciences, and P. V. Volkov, Senior Lecturer, Candidate of Engineering Sciences (Nosov Magnitogorsk State Technical University).

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