To perform research and detailed analysis of the stress deformed state of rocks around the haulage roadway based on the numerical modeling with the purpose to select the rational type and design of the haulage roadway support at the Beskempir field. Methods. A comprehensive research method has been used: review and generalization of references related to the study of the stress deformed state of a rock mass, improvement of the walling technology, in-situ and laboratory tests in the research and testing of rock samples strength; application of mathematical statistics and processing of experimental data using software products. The numerical modeling of the stress deformed state was done using the Examine 2D application with due account for the shape of broken rocks area, which is a 138х138х138 m regular triangle. Barton's Q-system was used to the RQD assessment. Findings. The numerical modeling of the stress deformed state of rocks in the tectonic fault zone of the haulage roadway at +230 m was performed, and the rock mass deformation zones were defined around the mine contours. The charts showing displacement of roof rocks and walls of the haulage roadway were built, where it was established that the maximum displacement was manifest over the tectonic fault zone. The following zones were identified: the rock mass instability zones, the rock mass instability zones with due account for its fracturing, the zones of stable and unstable rock masses of the haulage roadway. It was established that 41.6% of the working with the fault zone is unstable, and 58% of it is a more stable part. It is proposed to divide the haulage roadway into three sections depending on the rock stability with a certain type of support. Originality. Based on the study of the stress deformed state of the rock mass in the conditions of the Beskempir field, sitespecific unstable sections were identified. They ensured the selection of the support design with adjustable resistance. Practical implications. The application of support with adjustable resistance depending on the rock mass stability ensures minimization of costs for roadway support, maintenance of extensive sections of the working as well as enhanced mining safety in specific mining and geological conditions of the Beskempir field.

In this article, methods of reducing landslide phenomena and collapse of career of slopes, in the extraction of minerals with the open-pit mining approach are set out. The ways of uncovering upper argillaceous acclivities with the creation of buttresses made from rocky minerals are suggested. Also, technological frameworks of the establishment of acclivities of benches in primary resources, with preliminary conduct of the research on the deformation of the minerals from the drilling-andblasting activities are offered. On the basis of the dynamic processes of blasting and resistance of the massif to the breakage, there is a formula offered, for determining the rate of fracturing, and the methodology of calculation of the specific charge of the blasting substance, including and excluding the fracturing of the massif is substantiated. The technique of defining the parameters of buttresses, used in strengthening of the acclivities, piled with unstable argillaceous and friable minerals, is also suggested.

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Purpose. Research on the process intensification of gold-bearing product hydrometallurgical processing based on mechanochemical milling of the initial sulphide material. Methods. Mechanochemical activating (oxidation) of sulphide gold-bearing concentrate under conditions of superfine milling, sulphite-thiosulphate leaching of the milled product after liquid phase separation. The float concentrate sample with a particle size of -0.074 mm, the Au content is 15.5 g/t is tested. When loading into the mill of an initial concentrate sample weighing 300 g, 600 ml of a calcium hydroxide solution with a concentration of 143 g/l are added. The weight of balls loaded into the mill in relation to the concentrate weight is 10:1. The remainder of the solid product after milling is subjected to lea-ching with a sulphite-thiosulphate reagent. Findings. A sharp increase in the milled product of 10 µm fractions (from 14.05 to 34.63%) has been determined, and the mass fraction of gold in the final milling product decreases from 15.5 to 13.0 g/t. This corresponds to the recovery of gold into solution at this stage at the level of 16%. It has been found that with an additional supply of 1 g/l of copper sulphate for copper in the process of milling, it is possible to reduce the gold content in the milled product to 8.3 g/t. Thus, the recovery of gold into solution at the stage of milling increases from 16 to 48%. During the milling process, partial leaching of gold by reagents formed from its own sulphur has been revealed. It has been found that the transition of gold into solution is caused by the formation of a water-soluble hydrosulphide complex of gold during milling (AuS). As a result of leaching with the reagent, an additional 27% of gold has been recovered. Originality. Phase transformations of the sulphide gold-bearing beneficiary product as a result of mechanochemical activation have been determined. For the first time this process has been implemented to intensify the leaching process of gold-bearing mineral raw materials. Practical implications. The research results can be used in technological processes for the processing of refractory gold-bearing ores and technogenic raw materials.

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