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Irreversible strain is believed to be formed under in-plane shears. Normal strain varies proportionally to a respective shear in directions perpendicular to shear planes. This approach makes it possible to consider fracturing and pore development without applying Kachanov - Rabotnov kinetic equation for damage. The model, based on the maximum shear stress and the exponential law, provided the grounds to solve the problems on strain and failure of an elastic-creeping body at the stages of nonstationary and stationary creep. Stresses, creep strains, fracture start time and complete failure time, as well as position of the fracture front and its development velocity at any time are determined for the structural elements under study.

It is shown that all rockburst-hazardous ore deposits in Russia are exposed to gravitational-tectonic stress state of rocks, in which the prevailing role is played by horizontal stresses due to mountain-forming processes in the Earth's crust exceeding the vertical stresses several times. These horizontal stresses are the main cause of dynamic rock pressure manifestations. It is shown that energy characteristics of dynamic phenomena in mines can be calculated by the formula for seismic moment in the earthquake source, since there is no difference in seismic occurrences both in natural processes and in mine seismicity. Based on the law of self-similarity of the seismic process at different scale levels, a classification of dynamic rock pressure manifestations in mines has been developed, in which each type is characterized by the released energy and area (volume) of manifestations in mine workings.

The results of upgrading the software for parallel borehole method aimed at improving stress calculation accuracy and equipping software with a present-day interface are presented. To solve boundary value problems, an algorithm of linear combinations is applied. Experimental data obtained using borehole deformation gauge are processed.

It is shown that there is no such a model as intact rock mass, there is only a first one-dimensional approximation, i.e. experimental determination of principal stresses at the point of a future underground excavation. The case of ground surface above rock mass with an underground excavation affecting natural stresses is considered. In transition from open-pit to underground mining, the obtained results are essential when considering only correct problems which are the theoretical background for any calculation.

In order to verify and confirm the specified performance characteristics of arched yielding support made of a special interchangeable profile, the problem of determining its stress-strain state is considered. Most sensitive assemblies and support elements were identified for different operating modes, in which the limiting case - plastic strain development occurs first. It is shown that reliability and operability of an arched metal three-link yielding support depends on the strength of yielding assembly. At the same time, its maximum bearing capacity is provided in a hard operating mode.

The experiment of applying the upgraded Gidrorazryv system when studying stress field parameters in the Tashtagol mine and Yubileynoe deposit (Republic of Kazakhstan) is presented. The alternative layouts of measurement stations and the features of experimental hydraulic fracturing stress measurement are discussed. The experimental estimates of stress components in the vicinity of underground mine workings are presented.

On a site with a unit normal, in addition to the stress vector, the deformation vector is set as a vector of relative displacements of the site points (it is equal to the ratio of the displacement vector to the distance from the offset reference point to the site). The deformation vector has properties similar to the Cauchy stress vector (the principal vector and the principal moment of the deformation vectors referred to the medium element vanish). For an initially isotropic medium, the work of the stress vector on the site is calculated on the basis of changes in the deformation vector. It is shown that it is non-potential, i.e. depends on the nature of the change in the stress vector. Work is potential for an isotropic medium only on areas equally inclined to the principal axes of the stress tensor, i.e. on octahedral sites. This position is valid for the states of elasticity, plasticity, extreme deformation.

A practical solution for selecting the optimal mining system for Serebryakovskaya vein of the Irokindinsky deposit is presented. The geological and engineering conditions for mining the deposit were analyzed and the areas with complex conditions where specification of physical and mechanical rock properties is required were identified. Analytical calculations of main mining parameters were performed using numerical 3D modeling in the software package Map3D.

The use of mining and geological information systems for designing blasting operations in mining solid mineral deposits by the open-pit method is analyzed. The features of digital design in various domestic software products are noted and examples of their implementation at mining enterprises are given. It is shown that in conditions of a constant increase in the complexity of deposits being mined and planned to be mined, it is necessary to improve the digitalization of blasting operations to increase the overall efficiency and safety of open-pit geotechnologies.

Variants of the transition from two- to three-entry preparation of a series of very close shallow coal seams are considered, including methods for determining the minimum width of belt pillars based on the stability criteria of supported developing entries and prevention of geodynamic phenomena. A methodical approach is elaborated for the sequential transition from the production-tested two-entry preparation and mining of the extraction pillar to three-entry preparation.