Home – Home – Jornals – Journal of Mining Sciences 2025 number 4

The stress-strain research of rock mass is carried out, with verification by observations over underground openings at the Starobin and Petrikov deposits of potassium salt. The qualitative and quantitative indicators of the limit state zones in the vicinity of mine openings at moderate and great depths were compared using an integrated criterion. The formulas are proposed for determining sizes of limit state zones at great depths, with regard to geological structure of the test deposits. The numerical modeling algorithm of formation of rock blocks in the vicinity of underground openings on the basis of introduction of special block elements as systems of elastic and viscoelastic links is discussed. The research findings are applicable in stability assessment of mine openings in planning mining operations, and in selection of mine support and protection methods.

The article presents the ground surface deformation monitoring data for a 40 years-long period. The space and time parameters of geodynamic movements are revealed from the analysis of long-term observation over ground movements. The ground movement data base is created for the classification, modeling and estimation of ground movements, and for the analytical definition of patterns in big data arrays. The statistical and wavelet analyses of rates of change in vertical displacements of ground surface are performed. The ground surface zoning is carried out at the Sarany chromite deposits and in the adjacent areas with a town and industrial facilities. The results are useful for the detection of unknown parameters of geodynamic processes on ground surface, and for the prevention of accidents connected with instability of capital facilities during underground mining.

The estimation procedure of a displacement zone at a mined-out void filled with cemented paste backfill in mining of kimberlite deposits of ALROSA is described. The applicability of numerical stress-strain modeling and established normative standards is demonstrated. The deficiency of the current methods and norms in delimitation of hazardous displacement zones is identified. The proposed solutions conform with the actual conditions of the Internatsionalny and Aikhal Kimberlite Mines. Localization of a hazardous deformation zone nearby a mined-out area is demonstrated as a case-study of underground mining with cemented paste backfill in the Mir-Gluboky Mine. The displacement zone parameters at the Mir-Gluboky Mine are calculated.

The article addresses seismic activity induced and triggered by iron ore mining in Gornaya Shoria. In 2024 in the populated areas of Sheregesh and Tashtagol, perceptible earthquakes with local magnitudes 4.5 and 4.6 took place, respectively. A partial synchronization effect in seismic activity was revealed in the area of three mines, namely, Tashtagol, Sheregesh and Kaz, with simultaneous amplification of seismicity over a period from 2012 and to the present day. Seismic activity is spasmodic, with periodic attenuation both in terms of energy and number of seismic events, and with the subsequent recommencement. The energy of seismic activation events correlates with the mining rate and steadily rises as the latter grows.

The authors have developed the method of adapting blast designs and patterns to structurally complex mineral deposits on the basis of synthesis of theory of zonal rock fracture and theory of blast impulse. This article describes the sequence of practical adjustment of blast designs and patterns with regard to geological conditions. The method includes monitoring of rock mass, analysis of data, selection of techniques and their efficiency evaluation using an integral criterion embracing safety of blasting, quality of fragmentation and economic indicators. The authors propose classification of the techniques and their combinations, capable of reduction of seismic impact, flyrock and expenditure. Particular attention is given to the blast impulse peak pressure and duration control. The results enable adapting blast designs and patterns to nonuniform rock mass, and enhancing safety and efficiency of mining operations. The research prospects are connected with artificial intelligence technologies and digital data bases for forecasting blasting impact.

Coarse oversize fragments generated by blasting complicate loading and haulage of rocks, and this leads to the decreased productivity of labor and to the increased cost of mining. This article analyzes specific energy of roller-bit drilling as a drillability criterion as a case of the Koktaszhal deposit in Kazakhstan. Two electric drill rigs DML-1200 were additionally equipped with energy consumption recording facilities. The correlations between the powder factor, explosive fracture energy and ultimate compression strength of rocks, and between the average fragment and specific drilling energy are determined. For the blast design practice in open pit mining, it is substantiated to pass from mechanical specific energy of drilling to specific energy of explosive fracture and, further, to prediction of an average fragment of blasted rock. The experimental blasting operations at the Koktaszhal open pit mine show positive results which open prospects for the further research.

The authors discuss a variant of shrinkage stoping in mining steeply-dipping ore bodies of limited thickness. In the context of the majority of operating mines in Russia, numerical stress-strain modeling of gravitational stress state of an ore-rock mass is performed. The stress patterns in structural elements of the discussed geotechnology are determined as function of thickness and occurrence of the ore body, and subject to the technology implementation. It is found that rock mass quality greatly influences stability of different-purpose mine openings and ore pillars. The safe mining system parameters are determined and standardized for the typical geological and geomechanical conditions of the test deposits.

The geomechanical substantiation is provided for the technology of sublevel caving in mining close-spaced ore bodies with dirt parting of a varying thickness. The parametric model of sublevel caving includes the case of maximum advance of stoping front on sublevels. The computational patterns of maximum principal and shear stresses, as well as their concentration and relaxation in the main constituents of the mining system are obtained. The rock mass areas around various exposures, including preparatory and development openings, which are most susceptible to failure in case of complex tectonics, are identified. The analysis of different depths of driving fringe drifts and a decline in hanging wall of an ore body in depth of mining proves consistency of the adopted engineering solutions and safety of mining in varying geological and geotechnical conditions for the whole period of operation. The order and sequence of extraction of close-spaced ore bodies are validated to ensure caving of enclosing rocks toward mined-out void at the proper ground control. The parameters of underhand sublevel stoping, such that ensure safety and efficiency of mineral mining, are determined.

The authors obtained an analytical time law of freeze pipe temperature which ensures the constant thickness of a frozen wall at the stage of passive freezing. The time law is established using the equation of balance of heat flows at the phase interface. The correctness of the mathematical expression is proved by numerical modeling of freezing of a siltstone layer typical of conditions of shaft sinking in potash mines. The results are applicable in planning energy-efficient operating regimes of freeze pipes during passive freezing.

Scale modeling is essential in studying underground mine fires since large-scale experimentation is impossible because of unsafety while numerical modeling has limited accuracy and features high computational input. This article addresses an understudied issue of selection and substantiation of similarity criteria for the analysis of mine fires. The review of the current methods available for scale modeling of heat convection of air under high temperature differences on the basis of investigations of fires in buildings and tunnels displays their insufficient conformity with mine conditions owing to difference in geometry and in air flow behavior. The dimensional analysis reveals that similarity in laboratory modeling is achievable through observance of equality of the dimensionless Richardson, Euler and Froude numbers. The authors describe an emergency scenario, with switching-off of fans, when the only defining criterion is the Grashof number. The proposed approach makes it possible to design low-temperature lab-scale experiments to model air flow along mine openings during fire.

The analysis of organic collector adhesion to the surface of diamonds and kimberlite minerals in an aqueous medium determined the main characteristics of physical and chemical properties of the mineral-water-collector interfaces and the collector adhesion patterns at variation of the type and concentration of different class control reagents. It is found that control reagents reduce differently adhesion of an apolar collector to diamonds and floatable kimberlite minerals. This allows expecting a positive effect of the increased selective attachment of the collector to minerals being separated. The criterion of the collector attachment selectivity is proposed to be the ratio of adhesion energies of an apolar collector at diamond, talk and phlogopite. The test results demonstrated a tight correlation between the coating of diamond and kimberlite surfaces with an organic collector and the collector adhesion to diamond and phlogopite. The applicability of the proposed criterion for the selection of the control reagents for selectivity of attachment of apolar collectors in weakly mineralized recycled water is substantiated. The visiometric process analysis of attachment of a luminophore-bearing apolar collector at minerals of a diamond-kimberlite mix shows that the use of sodium hexametaphosphate and oxyethylene diphosphonic acid reduces amount of an organic collector on the surface of kimberlite and enhances stability of the collector adsorption on the surface of diamonds.

The influence of changeability of dry magnetic separation feed characteristics on the separation process efficiency is considered at the fixed operation modes of equipment is examined as a case-study of the Olenegorsk deposit ore. It is found that the major effect is exerted by the content of total iron: its increase in the feed is independent of the maximum linear size in the size grade and of the size modulus, and is accompanied with Fe_tot content growth in the magnetic fraction. The results of dry magnetic separation of a narrow particle size range prove that for - 80 + 2 mm, the correlation of Fe_tot content of the magnetic fraction (at В = 0.16 T) has a high approximation coefficient of 0.9461, which is reflective of a weak contribution of the feed size to separation efficiency. Regarding influence exerted on separation performance by the size modulus, it is found that the absence of ore pretreatment by sifting ensures reduction in loss of Fe_tot with the nonmagnetic fraction in 70% of cases.

Hydrofluoric acid (HF) proved to be the most efficient reagent for the flotation separation of feldspar minerals from quartz. This research aimed to improve the quality of Wadi Zirib feldspar ore for industrial applications. Furthermore, the effect of HF on the feldspar separation process was studied. Laboratory scale flotation experiments were conducted with quaternary ammonium salt solution as a cationic collector for feldspar minerals. HF was used as a surface modifier for the activation of feldspar minerals and quartz depression, as well. The optimum concentration of HF varied between 1800-2000 g/ton. A 1800 g/ton HF dosage gave a feldspar assay of 89.81% with 44.20% recovery. A 2000 g/ton HF dosage gave a feldspar assay of 85.05% with a 67.78% recovery. Overall, a suitable quality feldspar concentrate was obtained with a mass recovery of 52.11%, having a composition of 69.04% SiO₂, K₂O & Na₂O combined more than 11%, 17.34% Al₂O₃ and about 0.4% Fe₂O₃. This product could fulfill the requirements of glass, porcelain, ceramic, vitreous tiles and semi-vitreous tiles industries.

The aim of this paper is to present an approach to predict the performance of tunnel boring machines (TBM) in Iranian water conveyance tunneling projects using an artificial neural network (ANN) approach. With this respect, a database, including field data and machine parameters, was primarily compiled from the excavation of top five Iranian water conveyance tunnels. The database was then analyzed through ANN to yield an optimum predictive model for the rate of penetration. The results show that there is a close equation between actual (measured) data and predicted data with correlation coefficient of 0.94, and the values of coefficient of determination and root mean square error obtained in this research are equal to 0.90 and 1.2, respectively.

The authors analyzed water quality in manmade water bodies at the used and operating tungsten, molybdenum and complex ore mines in eastern and southwestern Transbaikal. The chemical analysis of water used atomic absorption spectrometry and inductively coupled plasma mass spectrometry. The standardized cumulative pollution index is calculated. It is found that the level of the environmental hazard of the test water bodies is abnormally high, which points at the environmental emergency and ecological catastrophe. The greatest threat to surface and underground water is made by the manmade water bodies at the Pervomaiskoe, Sherlova Gora, Bukuka and Bom-Gorkhon deposits. The recreational utilization of such water by people is unhealthy and inadmissible.