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

Podoprigora O. A., Chief Engineer of Mine Construction Shop, e-mail: opodoprigora@kazchrome4.enrc.com
Bondarenko G. V., Head of Engineering Department
Neverov A. M., Mining Engineer

Institute of Mining of Ural Branch of Russian Academy of Sciences (Ekaterinburg, Russia):
Ozornin I. L., Researcher

During the sinking of “Ventilyatsionnyy” shaft to the 970 m depth, there was carried out the complex of geomechanical and geophysical natural researches of stress-strain state of tubing support and surrounding rock massif. This complex of researches has shown that the currently applied sinking technological schemes and parameters of shaft support and inset openings does not completely meet the requirements of low strength and high-intensive massifs of serpentite rocks, which are characteristic for the deep horizons of «10-th anniversary of Kazakhstan independence» mine.
In the area of shaft junction with -560 m horizon, the stresses of more than a half of researched tubings became closed to the design strength. At the same time, the stresses of two tubings exceeded the tensile strength of cast iron, which led to the disturbance of edges and back edges of tubings.
In connection with this, on the basis of results of experimental and analytic researches, for the purpose of construction of junction of -600 m horizon of “Ventilyatsionnyy” shaft at the «10-th anniversary of Kazakhstan independence» mine, there is recommended the top down layer sinking with application of temporary reinforced-concrete support with the following installation of tubing shaft support, along with layer construction of reinforced-concrete support of junction opening. The temporary reinforced-concrete support is a combination of metallic grain, pressed to the check by anchors, and a concrete layer of the «B 25» grade (200-250 mm thickness). As a result, intense on the constant support of shaft and inset will be significantly lesser than in the earlier applied scheme, because the tubing support of shaft and reinforce-concrete support of junction opening will be installed after the realization of the most part of displacements of checks and adjoining massif.
The researches were carried out with the support of the Ministry of Education and Science of Russian Federation (agreement No. 8348) and integration project of Presidium of Ural Branch of Russian Academy of Sciences No. 12-I-5-2050 (12-И-5-2050).

1. Martynenko P. S., Syrkin P. S., Prokopov A. Yu., Stradanchenko S. G. Shakhtnoe i podzemnoe stroitelstvo. Chast 2. Tekhnologiya stroitelstva vertikalnykh stvolov (Shaft and underground construction. Part 2. Technology of construction of vertical shafts). Novochercassk : South Russian State Technical University, 2001, 260 p.
2. Geomekhanicheskie issledovaniya po opredeleniyu zakonomernostey razvitiya napryazhenno-deformirovannogo sostoyaniya prikonturnogo massiva i tyubingovoy krepi stvola «Ventilyatsionnyy» v protsesse prokhodki stvola v intervale 900–1200 m, a takzhe stvola «Kletevoy» v rayone sopryazheniya s gorizontom –560 m pri prokhodke okolostvolnykh vyrabotok : otchet o nauchno-issledovatelskoy rabote (Geomechanical researches on the definition of regularities of development of stress-strain state of near-boundary massif and tubing support of “Ventilyatsionnyy” shaft in the process of sinking of “Kletevoy” shaft in the range of 900-1200 m, as well as “Kletevoy” shaft in the area of junction with the horizon of -560 m during the sinking of shaft stations : report about the scientific and research work). Ekaterinburg : Institute of Mining of Ural Branch of Russian Academy of Sciences, 2012, 97 p.