«Transnational Company «KazKhrom» JSC (Aktobe, Kazakhstan):

Til V. V., President of a Corporation

Donskoy Ore-Dressing and Processing Enterprise – subsidiary of «Transnational Company «KazKhrom» JSC (Khromtau, Kazakhstan):

Bekeev M. M., Executive Officer

Institute of Mining of Ural Branch of Russian Academy of Sciences (Ekaterinburg, Russia):

Bolikov V. E., Head of Laboratory, Professor, Doctor of Engineering Sciences, e-mail: bolik@igduran.ru

Geological peculiarities of industrial area of the «10-th anniversary of Kazakhstan independence» mine are considered as complex. These peculiarities are characterized by the following factors:
- strong fragmentation of rock massif;
- powerful tectonic zones, falling towards the mined out space of shafts;
- low stability of rocks in exposed mine openings.
Mining and geological conditions of the central group of shafts of the «10-th anniversary of Kazakhstan independence» mine belong to the extremely difficult conditions, which do not have analogues in the country's practice.
Anisotropy of a stress field on the shaft perimeter was revealed on the support on the basis of inspection of the stress-strain state of shafts support of the «10-th anniversary of Kazakhstan independence» mine. At the same time, the maximum stresses in the support appear transversely to the line of maximum stresses in rock massif. Level of maximum stresses in separate tubings in the most powerful support reached -386 MPa.
In the conditions of Don chromite deposits, there is offered the combined scheme of sinking operations in the serpentinite massif. The most difficult site of shafts construction in serpentinite massif is the sinking of a shaft junction with the horizon, where takes place the most often support deformation. For these conditions, there is developed the special technological scheme of sinking of junction with advancing temporary support, consisting of anchors with reinforcing grid and monolithic concrete (250 mm thickness). Fastening of a shaft junction by permanent support is carried out after the junction sites sinking.
For the purpose of sinking operations in serpentinite rock massif, there was developed the construction technology with application of advancing strengthening anchor support and pliable keramzite concrete fixing space.
The developed and offered technologies of carrying out and fastening of deep shafts are tested on separate sites of constructed «10-th anniversary of Kazakhstan independence» mines. This makes it possible to recommend these technologies for industrial usage, for the purpose of accident-free opening and development of deep horizons of chromite deposits in rather difficult mining and geological conditions.

1. Bolikov V. E., Konstantinova S. A. Prognoz i obespechenie ustoychivosti kapitalnykh gornykh vyrabotok (Forecast and guaranteeing of stability of permanent mine openings). Ekaterinbug : Ural Branch of Russian Academy of Sciences, 2003, 374 p.
2. Bolikov V. E., Ozornin I. L., Kharisov T. F. Gornyy Informatsionno-Analiticheskiy Byulleten – Mining Informational and Analytical Bulletin, 2011, No. 11, pp. 66–67.
3. Bolikov V. E., Balek A. E., Bekeev M. M. Gornyi Zhurnal – Mining Journal, 2012, No. 1, pp. 55–59.