A. M. Freidin

Geomechanical substantiation of the parameters of a continuous chamber system of mining with caving of the roof rock

ConclusionsThe completed geomechanical analysis permits the following conclusions.1.The proposed mining system, with controlled caving of roof rock, allows mining to be done safely to depths of 900 m. Here, the span of the working can be up to 200 m. The following parameters (for a deposit 40 m thick) are recommended for production tests: height of caving zone h=40 mm; width of pillar and primary chamber bp=20 m and bc=20 m. A decrease in the thickness of the deposit increases the stability of the pillar and makes it possible to reduce the width bp while keeping the deformation of the pillar below the critical value.2.The initial stress state of the rock mass (before mining operations begin) affects the stability of the structural elements of the mine. For the Nikolaevsk deposit, where one horizontal component of the initial stress field is 1.5 times as great as the vertical component corresponding to the weight of the overlying formations and the other horizontal component is three times greater, it is recommended that stoping be done so that the direction of the operations front coincides with the direction of action of the minimum horizontal stress.

Hard mineral mining and raw material supply in Russia: Current state and the challenges

The article focuses on the current situation and challenges of the mineral and raw materials supply in Russian Federation.

Resource-saving geotechnologies for thick gently dipping complex ore deposits in the Norilsk region

The article gives an account of process designs accepted and introduced in mines at Norilsk-1, Talnakh and Oktyabrsky deposits and describes new promising patented mining methods successively trialed at a commercial scale or proposed for industrial testing.

Selection of deep level geotechnology in terms of the Vostok-2 orebody

The geomechanical state of the Vostok-2 tungsten orebody has been described. Numerical modeling has been used to characterize stresses in ore and rocks at different stages of extraction. Finally, the authors estimate stability of structural elements of the mining system alternatives used at the deep levels in the mine.

Development of ore metal provision for metallurgy industry in West Siberia

The authors discuss the current situation in the iron and steel industry and the iron ore mining in West Siberia, and evaluate the prospects and ways to improvement in the indicated sphere.

Geomechanical assessment of deep-level mining conditions in the Yuzhnoe complex ore deposit

The article analyzes geomechanical conditions of mining in rockburst-hazardous Yuzhnoe complex ore deposit located on the east of the Primorye Territory. Numerical modeling has revealed details of mining-induced stress field formation at different stages of stoping in the conditions of highly variable occurrence of the ore bodies. The study results have become the substantiation basis for enhanced safety and increased efficiency deep mining parameters.

Extraction of gold-bearing ore from under the open pit bottom at the Makmal deposit by room-and-pillar mining with backfill made of production waste

The article describes the experience of backfilling mined-out spaces in the north and south ore lentils of the Southern orebody of the Makmal deposit, Kyrgyz Republic, through gaps in the open pit bottom by using noncommercial dump material. The theoretical and technological aspects of safe underground extraction of safety pillar are discussed.

Intensification of Complex Ore Grinding and Opening by Hydropercussive and Cavitational Actions

The perspectives of new hydropercussive-cavitational method for ore preparation are shown by the example of poorly concentratable Cu-Ni and rare-metal ores.

Classification of Mining Methods for Deep Orebodies

Classifications of mining methods date back to the 1960s and use the following criteria: type and size of a mineral deposit, mined-out space support, state of a working excavation, type of a face, roof support, etc. Since that time mobile mining machinery has appreciably advanced, and some mining methods have lost their importance. Mobile mining equipment is effective in definite mining methods: in open mined-out space, mining with backfill and combined schemes. The transition to deep mining inevitably results in the sharply worsened technical and geomechanical conditions, and some well-established techniques for safe mining at rock burst hazardous deposits can not be considered self-sufficient. This paper puts forward a classification of deep mining methods, considering rock pressure control. The classification involves three classes: mining with backfill, mining with caving of overlying rocks and combined mining with backfill and caving.

Geomechanical assessment of compound mining technology with backfilling and caving for thick flat ore bodies

The authors develop a version of a compound technology with consolidating backfilling and caving for thick flat body of polymetals. Numerical evaluation shows that the technology with the cover caving above consolidating backfill ensures higher safety of mining.