College of Mining, NUST MISIS, Moscow, Russia:

V. A. Eremenko, Director of Research Center for Applied Geomechanics and Converging Geotechnologies, Doctor of Engineering Sciences, Professor of the Russian Academy of Sciences, prof.eremenko@gmail.com

Institute of Comprehensive Exploitation of Mineral Resources, Russian Academy of Sciences, Moscow, Russia:
I. I. Ainbinder, Head of Department, Professor, Doctor of Engineering Sciences

Polar Division, Norilsk Nickel MMC, Norilsk, Russia:
V. P. Marysyuk, Director of Geodynamic Safety Center, Candidate of Engineering Sciences
Yu. N. Nagovitsyn, Chief Engineer of Geodynamic Safety Center

The article presents studies aimed at development of new guidance for selecting ground support systems for permanent roadways, entries and stopes for the conditions of limit-stress or weak blocky rock mass of the Talnakh group of deposits. The ground support system is selected based on the rock mass quality assessment and Q Index which is accepted from the rock mass quality rating. Under conditions of difficult ground, high rock pressure, abundant water inflow and highly jointed rock mass, support systems at mine intersections should be adjusted and refined with regard to the geotechnical auditing of rocks and numerical modeling in Map3D using Rocscience programs Dips, RocData and Unwedge. The guidelines will cover ground support design for zones subjected to higher tectonic stresses, including weak blocky rocks, and it will also contain structural and technological requirements for the support systems with allowance for variability of geological and geotechnical conditions, which complicates prediction of rock mass behavior during heading and stoping. The ground support standards for horizontal excavations are aimed to improve stability of damaged hard rock mass through modern reinforcement techniques and using advanced methods to assess geomechanical and structural characteristics of rocks. The proposed approach to selecting ground support systems for permanent roadways, entries and stopes in limit-stress or weak blocky rock mass based on rock mass quality assessment is recommended for application in similar ground conditions, for example, in the Khabarovsk Territory, Buryatia, Gornaya Shoria, Khakassia, Kola Peninsula, Ural and other regions.
The authors appreciate participation of P. G. Patskevich, Candidate of Engineering Sciences, Senior Researcher at the Institute of Comprehensive Exploitation of Mineral Resources of RAS, and S. S. Neugomonov and P. V. Volkov, Candidates of Engineering Sciences of the Nosov Magnitogorsk State Technical University in these studies.

1. Eremenko V. A., Aynbinder I. I., Patskevich P. G., Babkin E. A. Assessment of the state of rocks in underground mines at the Polar division of Norilsk Nickel. Gornyy informatsionno-analiticheskiy byulleten. 2017. No. 1. pp. 5–17.
2. Rock Mass Quality Assessment Regulations for Mines of Norilsk Nickel’s Polar Division. Norilsk, 2018.
3. Recommendations for support and maintenance of exploration, development, temporary workings and stopes at Oktyabrskiy, Taymyr, Komsomolskiy and Zapolyarnyy mines of the Polar Division of MMC Norilsk Nickel. Norilsk, 2014.
4. Design Procedure for Intersections in Mines of Norilsk Nickel’s Polar Division. Norilsk, 2012.
5. Regulations of safe mining at Talnakh and Oktyabrskoe deposits, liable and hazard to rock bumps. Norilsk, 2015.
6. Barton N., Lien R., Lunde J. Engineering classification of rock masses for the design of tunnel support. Rock Mechanics. 1974. Vol. 6(4). pp. 183–236.
7. Barton N. Application of Q-system and index tests to estimate shear strength and deformability of rock masses. Workshop on Norwegian Method of Tunneling. New Delhi, 1993. pp. 66–84.
8. Laubscher D. H. A geomechanics classification system for the rating of rock mass in mine design. Journal of the Southern African Institute of Mining and Metallurgy. 1990. Vol. 90, Iss. 10. pp. 257–273.
9. Terzaghi K., Peck R. B. Soil Mechanics in Engineering Practice. New York : Wiley, 1967.
10. Louchnikov V. N., Eremenko V. A., Sandy M. P., Kosyreva M. A. Rock Bolting Design for Mines Exposed to Rockburst Hazard. Journal of Mining Science. 2017. Vol. 53, Iss. 3. pp. 504–512.
11. Neugomonov S. S., Volkov P. V., Zhirnov A. A. Tunnel support in weak rocks using self-fastening rock bolts SZA. Gornyi Zhurnal. 2018. No. 2. pp. 31–34. DOI: 10.17580/gzh.2018.02.04
12. Zubkov A. A., Latkin V. V., Neugomonov S. S., Volkov P. V. Prospective methods of support of mine excavations at underground mines. Conditions of Stable Functioning of Mineral Resource Complex of Russia. Moscow : Gornaya kniga, 2014. Iss. 1. pp. 106–117.
13. Kalmykov V. N., Volkov P. V., Latkin V. V. Substantiation of grouted rock bolting design for full-scale tests in Safianovsky mine. Aktualnye problemy gornogo dela. 2016. No. 2. pp. 27–35.
14. Kalmykov V. N., Latkin V. V., Zubkov A. A., Neygomonov S. S., Volkov P. V. The feature of construction increased combined fix on underground mines. Gornyy informatsionno-analiticheskiy byulleten. 2015. Iss. 3. Conditions of stable functioning of mineral-resource complex of Russia. Special issue 15. pp. 63–69.
15. Lushnikov V. N., Sandy M. P., Eremenko V. A., Kovalenko A. A., Ivanov I. A. Method of definition of the zone of rock massif failure range around mine workings and chambers by numerical modeling. Gornyi Zhurnal. 2013. No. 12. pp. 5–17.
16. Potvin Y., Wesseloo J. Towards an understanding of dynamic demand on ground support. Journal of the Southern African Institute of Mining and Metallurgy. 2013. Vol. 113, Iss. 12. pp. 913–922.
17. Bucher R., Cala M., Zimmermann A., Balg C., Roth A. Large scale field tests of high‐tensile steel wire mesh in combination with dynamic rockbolts subjected to rockburst loading. Proceedings of the 7^th International Symposium on Ground Support in Mining and Underground Construction (Ground Support 2013). Perth, 2013. pp. 221–232.
18. Bahrani N., Hadjigeorgiou J. Influence of Stope Excavation on Drift Convergence and Support Behavior: Insights from 3D Continuum and Discontinuum. Rock Mechanics and Rock Engineering. 2018. Vol. 51, Iss. 8. pp. 2395–2413.
19. Avinash P., Murthy V. M. S. R., Prakash A., Singh A. K. Estimation of rock load in development workings of underground coal mines - A modified RMR approach. Current Science. 2018. Vol. 114, No. 10. pp. 2167–2174.