Nosov Magnitogorsk State Technical University, Magnitogorsk, Russia:

A. M. Mazhitov, Associate Professor, Candidate of Engineering Sciences, prmpi@magtu.ru
S. A. Korneev, Associate Professor, Candidate of Engineering Sciences
I. A. Pytalev, Associate Professor, Candidate of Engineering Sciences

South Ural State University (SUSU), Chelyabinsk, Russia:
T. S. Kravchuk, Associate Professor, Candidate of Engineering Sciences

The objective of this study was to find a method to ensure stability of the north-western wall in Kamagan open pit mine in the course of extraction of mineral reserves from the safety pillar between the pit bottom and underground excavations. The pit wall stability estimation was based on the data of the analysis of geotechnical conditions and actual state of the pit wall rock mass, surveying, mathematical modeling of rock mass stress state and calculation of safety factors. The main sources of deformation activation are identified as the presence of numerous differently oriented tectonic fractures in the pit wall; potential incomplete backfilling or increase in the cemented backfill settlement after extraction of ore reserves in ore body No. 12; watering of weak weathered rocks and alluvium at the top of the pit wall, including the influence of process effluent; production blasting during stoping. Aimed to ensure the pit wall stability, it is recommended to create a counterforce made of gangue at the pit wall toe, with the substantiated values of volume and height.

1. Lowrie R. L. SME Mining Reference Handbook. Englewood : Society for Mining, Metallurgy and Exploration, 2002. 448 p.
2. Kaplunov D. R., Rylnikova M. V. Design of formation and development of mining systems with combined geotechnologies. Gornyy informatsionno-analiticheskiy byulleten. 2015. Special issue No. 45-1. Open-cast mining in the XXI century-1. pp. 3–17.
3. Chen J., Li K., Chang K.-J., Sofia G., Tarolli P. Open-pit mining geomorphic feature characterization. International Journal of Applied Earth Observation and Geoinformation. 2015. Vol. 42. pp. 76–86.
4. King B., Goycoolea M., Newman A. Optimizing the open pit-to-underground mining transition. European Journal of Operational Research. 2017. Vol. 257, Iss. 1. pp. 297–309
5. Wang N., Wan B. H., Zhang P., Du X. L. Analysis on deformation development of open-pit slope under the influence of underground mining. Legislation, Technology and Practice of Mine Land Reclamation : Proceedings of the Beijing International Symposium Land Reclamation and Ecological Restoration (LRER 2014). London : Taylor & Francis Group, 2015. pp. 53–58.
6. Kravchuk T. S., Pytalev I. A. Driving safety organization of traffic in quarry «Jusinskiy» during his modification. Sovremennye problemy transportnogo kompleksa Rossii. 2014. No. 5. pp. 46–49.
7. Kaihuan Zheng, Fuchuan Jiang. Research on Intrinsic Safety Method for Open-pit Mining. Procedia Engineering. 2012. Vol. 43. pp. 453–458.
8. Kaplunov D. R., Rylnikova M. V. Geotechnological and geomechanical features at open-tounderground mining transition. Gornyy informatsionno-analiticheskiy byulleten. 2015. Special issue No. 56. Deep open pits. pp. 67–79.
9. Blake K. Stress analysis for boreholes on department of defense lands in the Western United States: a study in stress heterogeneity. Proceedings, Thirty-Eighth Workshop an Geothermal Reservoir Engineering. Stanford : Stanford University, 2013. 12 p. Available at: https://pangea.stanford.edu/ERE/pdf/IGAstandard/SGW/2013/Blake.pdf (accessed: 15.04.2017).
10. Rylnikova M. V., Korneev S. A., Mazhitov A. M., Korneeva V. S. Substantiation of methods of mastering and systems of development of low-capacity ore bodies of Kamagan copper-sulfur deposit. Gornyi Zhurnal. 2014. No. 5. pp. 86–90.
11. Rules of provision of slope stability on coal cuts. Saint Petersburg, 1998. 208 p.
12. Gavrishev S. E., Kuznetsova T. S., Nekerova T. V. Method of substantiation of parameters of pit sides during open-cut mining of near-side reserves. Vestnik Magnitogorskogo gosudarstvennogo tekhnicheskogo universiteta imeni G. I. Nosova. 2010. No. 1. pp. 14–17.
13. Zhabko A. V. Theory of calculation of the stability of slopes and bases. Stability of dumps. Izvestiya Uralskogo gosudarstvennogo gornogo universiteta. 2016. No. 3. pp. 67–69.