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The article reports the lab experimentation on seismic/acoustic emission during different mode inter-block movement in rock mass. The fact that co–seismic displacement under induced earthquakes occurs along the existing interfaces is the basis for relatively simple tests on a slider-model plant. Using different materials as fracture fillers allowed modeling entire range of probable deformation modes. The deformation modes are conditionally grouped as creep or steady–state sliding, unsteady-state sliding and regular discontinuous sliding or stick-slip. The authors show that statistics of acoustic emission during sliding is described using the Gutenberg–Richter law. The largest “representative” events under shearing occur quasi–regularly, with probability much higher than follows from the law of frequency. The functional relation is found between the acoustic emission energy and the shear velocity.

The authors have developed and manufactured a test bench and a measurement apparatus for modeling movement of surfaces of faults with a pre–loaded granular filler in rock mass under trigger destressing. The trigger is a weak seismic wave generated by a single point–wise blow. It is found that displacement discontinuities appear under drop of force. It is shown that soft loading consumes much energy and destressing in this case results in smaller drop of forces but larger displacements. The authors find out that displacements are initiated by the destressing wave that lowers contact friction in the geomedium.

The authors have developed the FEM geomechanical model to describe evolution of temperature and hydrodynamic fields at the tailings dam of the Kumtor Gold Mine, Kyrgyzstan, in the permafrost region. The influence exerted by the temperature variation in the liquid waste accumulated in tailings pond and by the changes of size of impervious screen on the volume of filtrate material through the dam is evaluated in numerical experiments. It is shown that the pressure variation rate in the monitoring hole can be the indicator of the impervious screen rupture.

Under analysis is the experimental testing of interaction between the limit of strength and the acoustic Q–factor in terms of Kasimov deposit limestone. The limit of strength is found using two procedures, namely, direct method and interpolation, which are compared. The authors illustrate the advantage of the acoustic Q–factor procedure in assessment of damage and residual strength of rocks as against the method of elastic wave velocities. The resultant relations can be used in assessment of residual strength and remaining life of pillars and roofs in underground excavations.

The study covers the issues of strength of rocks under three–dimensional stress, elastoplastic model with variable parameters of plastic flow, algorithm of problem solving with Stavrogin’s strength, evaluation of the numerical model correctness and the scope of use of the Coulomb criterion. The problem implementation uses Abaqus software. The calculated data on limit state zones around an underground excavation are compared with the strength conditions by Stavrogin and Coulomb.

The authors propose a physico–mathematical model to describe nonequilibrium filtration and diffusion of free and absorbed gas in coal in the framework of heterogeneous medium mechanics considering physical desorption. The model consists of a set of nonhomogeneous parabolic equations with a rigid source member. In terms of problems on propagation of compression and rarefaction waves, effect of the nonequilibrium desorption on the width of these waves is revealed. The problem on initiation and steady–state of a shock wave in coal is solved.

The authors have plotted the lines of energy flow in the problems on uniform vertical force applied at the boundary of an elastic half-plane and on indentation of a smooth pressing tool in a rigid-plastic medium. The influence of stresses on displacement velocities is analyzed. As an example, formation of compaction zone under ram block is studied.

The article presents the forecasting procedure for physico–mechanical properties of mine waste based on the data of geological and geophysical surveying, including electric resistivity tomography, in order to establish connection between physical properties of the material. In terms of a hydraulic fill at an open pit coal mine, the authors predict the change in the physico–mechanical properties of the hydraulic fill under a dump embankment.

The author describes physical simulation of natural stone block cutting using a plastic substance and specifies factors influencing energy input and quality of the cutting process. Recommendations on impact load application sequence, pattern of drill holes and sizes of cut stone blocks are given.

In focus is the current objective of energy efficiency improvement in mining in Russia and other countries of the world. The world tendencies toward new unconventional renewable energy sources and their introduction in closed–cycle resource–saving technologies are reviewed. In the capacity of the renewable energy sources, the authors discuss lithological pressure and elastic vibrations of rock mass, kinetic energy of gravity flow of backfill mixtures and fluids during backfilling and mine drainage, potential energy of gravity force of heavy trucks, energy of return air flows in mine ventilation and this energy recovery, etc. The authors think that conversion of these kinds of energy into electric energy during hard mineral mining will allow solution to ecological problems and enable development of allied branches in “small power engineering,” including essential reduction of external energy consumption in underground mines.