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The article describes integrated experimental research into mechanisms of change in physical properties of soil under electrochemical reinforcement implemented in a test area. The monitoring methods involved geological engineering survey, laboratory testing of soil samples, as well as statistical, geomechanical, seismic, electrical and georadar sounding. It has experimentally been proved that three zones (strengthening, dehumidification and transient) are formed in the interelectrode space; the ranges of space and time change in humidity, deformation modulus, cohesion, internal friction angle, elastic wave velocities, electrical resistivity and integral parameters of georadargrams are found. The authors substantiate ways of improving efficiency of two- and one-stage schemes of electrochemical soil reinforcement and application areas of geophysical monitoring techniques.

The authors construct 3D probabilistic cellular automata to model accumulation of elementary damages and evolution of their cluster structure. Kinetic dependences of number of the clusters and evolution of time correlation functions are studied for the number of clusters and number of elementary damages. It is proved that intersection of the time autocorrelation function of a random process “number of impulses of emission” with the local minimum in the field of negative correlation can be interpreted as a sign of transition of a loaded material to a stage immediately preceding irreversible failure.

The presented information is a part of the authors’ research in the field of effect exerted by innovative development of coal business on competitiveness of a region. The described conceptual model of innovation-based transformation of the coal industry in Kuzbass rests upon coordination of interests of business and authority with the purpose to improve competitive ability of a region. With this model, it is proposed to develop a route map for modernization of regional coal mining industry, which should create conditions for the coal industry to change over from being a donor to becoming a driver of economics in the Kemerovo region. At the same time, this will enable appraisal of federal and regional reserves to be efficiently used in implementation of this ambitious, difficult and expensive “project”.

The article describes the analysis of theoretical and applied aspects of ecological risk management in terms of coal mining and processing companies, as well as assigns and solves tasks on identification of ecological risks, assessment of probability of undesired events, determination of structure of probable damage, assessment of risk, estimation of technological and organizational methods and measures of influence on ecological risk to reduce and avoid it, and decision-making on practical introduction of particular risk management and control measures. The groups of technological and organizational measures aimed to minimize or neutralize risks are considered. The key result of the research is the package of measures of ecological risk reduction, in particular: technologies of ultradeep purification of dielectric liquids; introduction of processing equipment for used-up tyres of heavy open pit dump trucks; formation and updating of quality management system; improvement of efficiency of reclamation of disturbed lands; treatment of hydraulic mining and coal processing waste.

Deep-level mining needs extra data on physical behavior of rocks at great depths (under high stresses). Without such data, any computations for deep-level technologies based on analogy with shallow-depth technologies are non-diagnostic. Elastic moduli of rocks may depend on the accumulated plastic deformation and their reduction is considerable in the known tests of metals. It seems interesting to study the influence of this property of rocks on distribution of residual stresses and displacements. Elastic transformation of an excavation after drivage (relief of stresses) largely affects surrounding rock mass and results in origination of a transition layer around the excavation. A local drop of deformation energy takes place in the surrounding rocks, which reduces stress concentration. The problem is studied based on an analytical solution obtained for a deep round excavation subjected to constant value compressive stresses at infinity and a solution taking into account the Young modulus. The article offers an algorithm for geomechanical condition of tocks and determines ranges for stresses and displacements in the zone of influence of excavation. Examples of calculations are given, and the results are discussed.

The article discusses optimization of microseismic monitoring in hard mineral mining. A procedure has been developed to estimate accuracy of positioning of seismic event hypocenters. The advantage of combination observation system with distributed underground receiving antennas and additional sensors installed at a distance from a productive seam plane is illustrated. The obtained results are important for optimizing observation systems and improving efficiency of microseismic monitoring in hard mineral mining.

Based on DEM, the problem on uniform shearing of granular material specimen is considered, the shape of the particles was chosen to be spherical, with assigned distribution per radii. At interfaces of the particles, dry friction and viscosity were taken into account. Loading was implemented as simple and broken trajectory shearing. The load trajectory was broken by means of sudden change in the shearing direction. It has been found that in this case, dilatancy rate and angle between axes of stress tensors and strain rates change jump-wise. The discrete medium shows the properties of the continuum model of granular material with internal friction and dilatancy. The authors discuss a criterion of the continuum model to be equivalent to the initial discrete model. Applicability of the numerical results to the continuum modeling of deformation is demonstrated.

The article reports electromagnetic emission (EME) measurements in rocks using REMI-2 equipment and recording-diagnosing system RDS REMI-3 developed jointly at the Institute of Mining and Novosibirsk State Technical University. REMI-2 measures EME signal strength and displays the results digitally. RDS REMI-3 is advantageous over earlier designed equipment as it downloads measurement data in the embedded memory. The EME records are displayed as oscillograms to enable detecting initial stage of rock failure based on analysis of change in structure, parameters and spectrum-and-time behavior of EME signals.

Under consideration is feasibility of voltage stabilization in permanent-magnet synchronous generator with variable frequency in self-contained systems of power supply. The method of stabilization is based on varying frequency of rotation of generator shaft. The authors have derived analytical expression for regulating characteristics and determined required ranges for rotation frequency variation at preset parameters of generator and loading. The symmetry conditions are found for a regulating characteristic relative to rotation frequency change.

The analysis involves influence of sulfhydryl phosphorus-containing collectors (SPC) on flotation of copper-nickel ore bearing metals from platinum group. Efficiency of SPC and butyl xanthate combination is illustrated, and their optimal ratio is determined. The authors study influence of the test agents on electrode potential and hydrophobic behavior of pyrrhotine, pentlandite and platinum black. UV and IR spectrophotometry has shown origination of disulfide di-isobutyl dithiophosphinate on the surface of pyrrhotine.