Experience of CAE Fidesys application in numerical geomechanical modelling of Zhdanovskoe deposit

The Zhdanovskoe copper-nickel sulfide ores deposit is located in the north-west of the Murmansk region and is a mineral raw material source for JSC «Kola MMC». The main mining method used is sublevel caving. In some areas, due to the complex shape of the ore bodies, the open stoping mining method is used which requires determining stable parameters of stopes and pillars. It is necessary to study the stress-strain state of the deposit to ensure safe mining conditions. One of the possible solutions is the modeling of the stress-strain state of rock mass using the finite element method, for example, CAE Fidesys, which is FEMbased software. The use of CAE Fidesys for solving geomechanics tasks allows creating models of individual excavation units to determine the stability of stopes and pillars, and large-scale models that include several ore bodies and areas of the host rock mass. The article considers solutions of both types of geomechanic tasks using CAE Fidesys for conditions of the Zhdanovskoe deposit.

Conditions and opportunities for the use of digital technologies in modern industry education

Важнейшими в современном образовательном процессе являются инновационные интерактивные приемы, способные расширять кругозор учащегося, помогающие творчески подходить к изучаемому объекту. Фактическими материалами, которые могут представлять интерес как для учащихся, так и для преподавателей и методистов высших и средних образовательных учреждений в области естественнонаучных знаний, является значительный научный и методический материал, накопленный ГГМ РАН, а также академическим сообществом в целом. В свою очередь новые условия дистанционного взаимодействия и передачи информации требуют новых интерактивных форма с использованием цифровых технологий. Все это помогает усилить научную емкость и интеграцию в образовательную среду, способствует расширению коммуникационной площадки в системе непрерывного отраслевого просвещения и образования.

On determining the parameters of face blocks during mining operations with backhoes

The backhoe hydraulic shovels (backhoes) have been widely used in open-pit mining operations in the Kuznetsk coal basin since the early 2000s. Now their number is growing every year, both because new operations begin on new sites, and because of the backhoe advantages. However, up to now parameters of their operation, more particularly the parameters of the face blocks, are often taken according to the actual data, i.e. based on the accumulated experience of the mining companies, and are not calculated using the approved scientifically validated methods. In the given article the authors give some preconditions for creation of a uniform methodology to calculate parameters of the face blocks depending on mining-geological and miningtechnical conditions. It is noted that the manufacturers of excavation equipment quote the data corresponding to the maximum possible parameters of the equipment operation, in particular the height of the excavated layer, as a result of which it is rather difficult to apply this in practice. Preliminary conclusions about the need to take into account the diversity of the above conditions and their interrelation with the parameters of a particular model of the excavation and loading equipment have been made.

Specific features in operation of road construction equipment in the Far North

The development of the Far North goes hand in hand with the use of road construction equipment. The article addresses the main factors that affect the operation of this equipment in extremely cold climates. The effect of low temperatures on the operation of machines and individual units is examined. In particular, information is provided on the effect of low temperatures on operation of the hydraulic drive, power plants, and metal structures. The influence of the requirement to observe the methodological recommendations regarding the ergonomics and physiology of workers on increasing the cost of works with the use of road construction machinery has been noted.

Regularities in formation of stressed state in roof rocks of mined-out space during development stage

Formation of the stress-and-strain state of the rock mass in the roof of mined coal seam depends on the development of the mined-out space. It is believed that the coal seam is located deep enough and it can be assumed that the effect of the daylight surface on its condition can be neglected. In this case, the solution is based on the analytical approach using methods of the complex variable theory and it is reduced to the construction of a single permission analytical function. The paper reviews the evolution of the deformation processes in development of the mined-out space in presence of a hard-to-collapse elastic roof, which is capable of sinking smoothly over time, without sudden caving on the landings on the floor. A particular attention is paid to the phase when the roof and the floor touch each other, i.e. the roof caving, starting from the first touching and up to its complete caving. In this case, two sections of the hanging roof are formed, that are gradually reducing in length as the dimensions of the mined-out space increase. The area of roof caving is progressively increasing, and the vertical compressive stresses at the boundary are gradually rising, tending to reach the initial vertical pressure at the depth of the formation before the start of its mining. Tension zones relative to the horizontal and vertical stresses are identified, that are attributed to the areas of roof hang-up, which may determine the location of zones with higher methane and formation water permeability, both in the rocks between the seams and in the coal seam.

The typology of rubies and their industrial significance

Information on the International Genetic Classification of Noble Corundum is given. The scheme of location of the main deposits and occurrences of ruby-bearing complexes of the world is attached: 1 – magmatic; 2 – metamorphogenic; 3 – sedimentary (residual ancient crusts of chemical weathering, alluvial and dealluvial-alluvial placers). The location of ruby objects is shown, including the largest areas of depleted, currently operating and promising for the near future ruby deposits in 36 countries around the world. The main typological features of rubies are described. It is emphasized that all properties of rubies are determined by their primary indigenous origin. The typology of rubies is based on the principles of the relationship between magmatism and metamorphism in the formation of the groups under consideration. Hydroblasting and selective crushing methods for mining of corundum-bearing complexes are characterised. The trend towards increased research into the commercial exploitation of the primary sources of ruby-bearing complexes is highlighted. In countries with highly developed mining industries, underground mining is the main way to extract gemstones.

Methodological approach to characterizing pollution of natural water bodies using satellite data with account of aggregation of finely dispersed mineral processing waste

The level of the environmental impact of the mining industry specifies the urgency of ecological management of the natural resources based on the satellite monitoring data. The high content of the suspended mineral particles in the industrial waters and the requirement to reduce their access to the natural water reservoirs determine the need to characterize the mininginduced pollution that can be carried out correctly with due account of the aggregate stability of dispersions. In spite of the theoretical concepts, prediction of the particles aggregation is limited by a lack of data on their interaction parameters. In order to parametrize the interactions in the mineral-water-mineral system it is proposed to use experimental data on aggregation of finely dispersed particles, obtained by the laser diffraction method in the equilibrium conditions. For this purpose the procedure of the experimental appraisal of the effective Hamaker constants has been elaborated using ores of developed deposits of the Kola mining complex as an example. The authors have studied the conditions of the surface layer of natural water reservoirs in the most industrially developed central part of the Murmansk region and defined characteristics of pollution with finely dispersed by-products of the mineral raw material treatment, according to the satellite observation data of the spatial distribution of the normalized difference turbidity index. The authors have established that the least propagation of the pollution into the natural water reservoirs is observed in the case of the apatite-nepheline ores processing by-products, which is explained by the effective aggregation of the finely dispersed nepheline particles. The proposed approach to apply data on mineral particles aggregation for interpretation of the satellite observations does not require carrying out in-situ observations and makes it possible to identify the mining-induced pollution of natural water reservoirs in industrial territories using suspended particles.

Application of numerical and physical modeling in designing of an X-ray luminescence separator intended for separation of ores containing luminescent minerals

The paper demonstrates the application of numerical and physical modeling to justify the design of the X-ray fluorescence separator’s material handling system. The Rocky DEM software package is a numerical modeling tool that uses the discrete element method as a mathematical apparatus. In order to increase the efficiency of the X-ray luminescence separation, the authors suggest including an additional element in the separator’s material handling system, i.e., a drum spreader that combines a handling device and an actuating mechanism. It was found out that the best loading of the drum spreader cells, in which the number of several pieces in one cell is reduced by at least 15%, is provided by a Vibrating feeder conveyor with a triangular cross-section of the profiled part of the tray compared with the tray of parabolic cross-section. In addition, the triangular section provides a double decrease in the number of pieces with rotational movement around their axes and, accordingly, an increase of at least 5% in the average velocity of the ore flow movement along the tray. The simulation of the material handling system has shown the need to reduce the height of the end partition of the drum spreader between the cells to 45 mm, which eliminates the collision of ore pieces with the partition and subsequently, their movement in the direction of rotation of the drum spreader on its outer surface, as well as the unpredictable escape of the ore pieces beyond the working space of the separator.

Geodynamic zoning of the southwestern part of the Talnakh Orogenic System

This study focuses on the markers of tectonically stressed zones inside the rock mass, that were identified during the regional geodynamic zoning of the mine fields of the Talnakh orogenic system. Identification features for tracing geodynamically active structures within the western flank of the Talnakh orogenic system have been identified based on morphometric analysis of the Tunguska series sediments, which are the upper layer of the ore-bearing intrusions and associated ore deposits. In the larger morphostructural groups, the boundaries of contrastingly alternating zones of elevated and depressed absolute depths at the base and the roof of the Tunguska series sediments represent the boundaries of tectonic blocks of different elevation levels with sharply contrasting indices of terrain stress. The circular-shaped structures highlighted in the morphostructural schemes spatially coincide with the tectonic forms were formed as the result of strike-slip and torsional processes. A heterogeneity, which is reflected in the allocation of blocks with different values of the stress distribution coefficient (K) is identified in the initial stress field of the Tunguska series sediments. The boundaries of the geodynamic blocks that were identified using to different methods are identical. It is established that the assumed faults correspond to the faults identified based on the detailed exploration data.

Innovations in mentoring as part of the strategy to improve the quality of talent pool for the Russian mineral and raw material sector

In contemporary Russian practices, mentoring is a multifaceted innovative 'human resource technology' aimed at developing professional skills and corporate competencies, as well as systematic and targeted participation in professional development of employees who have insufficient work experience or have difficulties in mastering new technologies and work techniques. Today, the institution of mentoring is an open industrial, educational and social space where the mentor transfers not only readymade ways to solve production problems, but also teaches how to use available intellectual and material resources. Although the mentoring process in its traditional sense does not require large financial investments, most business entities, industrial enterprises and companies are more actively using training, coaching techniques and various forms of internships, which are valuable forms of professional development of employees, but, as our research has shown, they do not have the potential that the targeted on-the-job mentoring possesses. With all the variety of forms and programmes of mentoring activities, there is a clear lack of innovative ideas aimed at improving its efficiency, which fully applies to the mentoring of students who take their work placements during vocational education, which is the subject of the research presented in this article. The literature and research studies do not fully analyse the potential of the third mission of universities regarding the issue of targeted mentoring aimed at more proactive and advanced applied training of graduates, capable of responding to "the great challenges". The article highlights the mentoring models used in foreign companies, which are similar to the types of mentoring technologies successfully implemented by Russian enterprises.