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Date submitted2023-06-01
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Date accepted2024-03-05
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Date published2024-08-26
Analyzing friction bolts load bearing capacity in varying rock masses: an experimental study in Anti Atlas Imiter silver mining region, Morocco
This study analyzes how key factors impact friction rock bolt capacity using standard pull-out tests, focusing on 39 mm diameter, 180 cm long split-tube bolts. We investigate bolt performance dependence on rock mass rating (RMR), time after installation, schistosity orientation, surface roughness, and installation quality. The aim is optimizing bolt design and implementation for enhanced underground stability and safety. Results show RMR strongly exponentially correlates with pull-out resistance; higher quality rock masses increase capacity. Anchorage capacity significantly rises over time, especially for RMR above 70. Increasing angle between bolt axis and rock foliation from 0 to 90° boosts pull-out response. Reducing borehole diameter below bolt diameter grows bolt-ground friction. Empirical models estimate load capacity based on RMR, time, orientation, diameter, roughness and installation quality. These reliably predict bolt performance from site conditions, significantly improving on basic RMR methods. Experiments provide practical friction bolt behavior insights for typical rock masses. The data-driven analysis ensures models are applicable to actual underground scenarios. This enables tailored optimization of bolting configurations and supports. Methodologies presented should improve safety, efficiency and cost-effectiveness of reinforced mining and tunneling. Overall, this study fundamentally furthers friction bolt performance understanding, enabling superior underground support design.
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Date submitted2022-05-11
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Date accepted2023-02-20
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Date published2023-08-28
Application of the support vector machine for processing the results of tin ores enrichment by the centrifugal concentration method
The relevance of the research is due to the acquisition of new knowledge about the features of the applicability of the support vector machine, related to machine learning tools, for solving problems of mathematical modeling of mining and processing equipment. The purpose of the research is a statistical analysis of the results of semi-industrial tests of the Knelson CVD technology on tin raw materials using the support vector machine method and the development of mathematical models suitable for further optimization of the technological parameters of the equipment. The objects of research were the products obtained as a result of the operation of hydro-cyclones, as well as the technological parameters of the operation of centrifugal concentrators. The work uses classical methods of mathematical statistics, the least squares method for constructing a linear regression model, the support vector machine implemented on the basis of the Scikit-learn library, as well as the method of verifying the resulting models based on the ShuffleSplit library. A general description of the process of testing the Knelson concentrator with continuous controlled unloading in relation to the enrichment of tin ores is presented. The results obtained were processed using the support vector machine. Regression models are obtained in the form of polynomials of the second degree and in the form of radial basis functions. A significant non-linearity is shown in the dependence between the content of the valuable component in the tailings and the values of the technological parameters of the apparatus.
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Date submitted2022-04-05
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Date accepted2022-07-21
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Date published2022-11-10
Development of resource-saving technology for excavation of flat-lying coal seams with tight roof rocks (on the example of the Quang Ninh coal basin mines)
- Authors:
- Vladimir P. Zubov
- Le Quang Phuc
It is shown that the creation of the variants of resource-saving systems for the development of long-column mining is one of the main directions for improving the technological schemes for mining operations in the mines of the Kuang Nin coal basin. They provide a reduction in coal losses in the inter-column pillars and the cost of maintaining preliminary workings fixed with anchorage. The implementation of these directions is difficult (and in some cases practically impossible) when tight rocks are lying over the coal seam, prone to significant hovering in the developed space. In the Quang Ninh basin, 9-10 % of the workings are anchored, the operational losses of coal reach 30 % or more; up to 50 % of the workings are re-anchored annually. It is concluded that the real conditions for reducing coal losses and the effective use of anchor support as the main support of reusable preliminary workings are created when implementing the idea put forward at the St. Petersburg Mining University: leaving the coal pillar of increased width between the reused mine working and the developed space and its subsequent development on the same line with the stoping face simultaneously with the reclamation of the reused mine working.
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Date submitted2021-04-20
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Date accepted2022-04-26
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Date published2022-07-13
Prediction of the stress-strain state and stability of the front of tunnel face at the intersection of disturbed zones of the soil mass
The article presents a numerical solution of the spatial elastic-plastic problem of determining the stability of the tunnel face soils at the intersection of disturbed zones of the soil mass. The relevance of the study is related to the need to take into account the zones of disturbed soils when assessing the face stability to calculate the parameters of the support. Based on the finite element method implemented in the PLAXIS 3D software package, the construction of a finite element system "soil mass-disturbance-face support" and modeling of the intersection of the disturbed zones of the soil mass were performed. To assess the condition of soils, deformation and strength criteria are taken. The deformation criterion is expressed by the value of the calculated displacement of the tunnel contour in the face, and the strength criterion - by the safety coefficient until the maximum values of the stress state are reached according to the Coulomb–Mohr criterion. The results of the study are presented in the form of histograms of the safety coefficient dependences on the distance to the disturbance at different bending stiffness of the face support structure, as well as the isofields of deformation development. The parameters of rockfall formation in the face zone at the intersection of zones of disturbed soils were determined. The local decrease in strength and deformation properties in the rock mass along the tunnel track should be taken into account when assessing the stability of the tunnel face and calculating the parameters of the support. Within the framework of the constructed closed system, a qualitative agreement of the simulation results with the case of a collapse in the face during the construction of the Vladimirskaya-2 station of the St. Petersburg Metro was obtained.
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Date submitted2020-08-28
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Date accepted2020-12-16
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Date published2020-12-29
Metrological support of equipment for geophysical research
The article discusses the problems associated with metrological support of equipment for geophysical research, issues of ensuring the uniformity of well measurements, the creation of Russian standards for calibrating well equipment when determining the porosity coefficients and oil, gas, water saturation, determining the parameters of defects during well cementing and technical condition of casing strings and the water-oil-gas flow. The problems of creating full-fledged methods for measuring the parameters of oil and gas fields with conventional and hard-to-recover reserves have been investigated. The key directions of development of the Russian metrological support of geophysical well measurements were determined. The tasks that need to be solved to create metrological support for geophysical well logging as an industry that meet international standards are indicated. The expediency of creating a Russian Geophysical Center for Metrology and Certification, the need to develop a new and update the existing regulatory framework, which will allow Russian geophysics to reach the level of world leaders in the field of geophysical research, are substantiated.
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Date submitted2018-08-25
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Date accepted2018-10-26
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Date published2019-02-22
Metrological support of monitoring systems based on unmanned aerial vehicles
- Authors:
- E. A. Kremcheev
- A. S. Danilov
- Yu. D. Smirnov
The article discusses the fields and methods of application of unmanned aerial vehicles (UAV). Current legislation in Russia and in the world, significantly limit the use of UAV in monitoring. For the first time, we present a solution to the problem of a monitoring measurement system included in the state register of measuring instruments using the example of the basic UAV model. We conducted an analysis of promising approaches to the creation of UAV metrological and methodological support, as well as ways to adapt their target load to meet the challenges of operational monitoring of air pollution.
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Date submitted2018-01-04
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Date accepted2018-03-08
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Date published2018-06-22
Influence of mining-geological conditions and technogenic factors on blastholes stability during open mining of apatite-nepheline ores
- Authors:
- M. N. Overchenko
- S. A. Tolstunov
- S. P. Mozer
The paper presents the results of borehole stability research and considers possible causes of emergencies. The features of the blast hole drilling process are analyzed taking into account the properties of the rock. Based on the distribution of speed of drill fines removal from the well, an algorithm for selecting drilling modes is proposed. The nature of change in the size of the holess over time has been analyzed. This paper investigates the influence of rock fracturing and its water content on borehole stability. Possible options for eliminating the man-made impact on the massif near holes and options for fixing the hole walls with soft shells are suggested. The experimental data on the installation of shells for the conditions of open mining of apatite-nepheline ores are given. The operability and effectiveness of the technology is proved.
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Date submitted2017-11-09
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Date accepted2018-01-02
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Date published2018-04-24
Analyis of government support tools for mining companies in the Russian Arctic zone
The paper focuses on the development of mining companies in the Russian Arctic zone in the context of searching for new ways to improve government control over the development of the Arctic zone. Existing outer restrictions imposed upon Russia and changes in the global financial market not only determined a paradigm shift to regional government control, but also dictated the need to search for new mechanisms of state influence on the regional economy. Primarily it concerns the development of growth zones based on utilizing resource potential, creation and implementation of tools aimed at attracting investments to the Arctic zone and offsetting the factors of northern appreciation for mining companies. With this in mind, government support of specific regional development projects is becoming an urgent issue. The authors analyze new approaches to the development of public management in the Russian Arctic zone, for mining companies in particular, aimed at creating special economic conditions that would stimulate the operation of plants extracting mineral resources. Research methodology is based upon the analysis of factors restricting economic development and growth of the Russian Arctic zone and mining companies in the first place, as well as analysis of possible tools to support mining plants operating in the Arctic territories (advanced development zones, industrial clusters, «supporting zones»). The authors define priority goals and prospects of implementing such operation mode for mining companies in the Arctic zone, and propose a list of possible measures of government support needed to stimulate development of mining companies and the entire Arctic economy of Russia.
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Date submitted2016-09-04
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Date accepted2016-11-14
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Date published2017-02-22
Methodology of reducing rock bump hazard during room and rillar mining of North Ural deep bauxite deposits
- Authors:
- D. V. Sidorov
The article describes practical experience of using room and pillar mining (RAPM) under conditions of deep horizons and dynamic overburden pressure. It was identified that methods of rock pressure control efficient at high horizons do not meet safety requirements when working at existing depths, that is explained by changes in geodynamic processes during mining. With deeper depth, the geodynamic processes become more intensive and number of pillar and roof failures increase. When working at 800 m the breakage of mine structures became massive and unpredictable, which paused a question of development and implementation of tools for compliance assessment of used elements of RAPM and mining, geological, technical and geodynamic conditions of North Ural bauxite deposits and further development of guidelines for safe mining under conditions of deep horizons and dynamic rock pressure. It describes reasons of mine structure failures in workings depending on natural and man-caused factors, determines possible hazards and objects of geomechanic support. It also includes compliance assessment of tools used for calculations of RAPM structures, forecast and measures for rock tectonic bursts at mines of OAO “Sevuralboksitruda” (SUBR). It describes modernization and development of new geomechanic support of RAPM considering natural and technogenic hazards. The article presents results of experimental testing of new parameters of RAPM construction elements of SUBR mines. It has data on industrial implementation of developed regulatory and guideline documents at these mines for identification of valid parameters of RAPM elements at deep depths.
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Date submitted2014-07-02
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Date accepted2014-08-24
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Date published2014-12-22
Informational support for prompt project management of microfault exploration
- Authors:
- V. V. Nazimko
Geologic, technological, psychological, economic and organizational uncertainty impede extraction from coal seams that are corrupted by microfaults. We propose the exploration and extraction from the corrupted coal seams in a project management mode.
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Date submitted2009-10-18
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Date accepted2009-12-17
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Date published2010-09-22
Reuse of development workings as an element of providing the effective coal output
- Authors:
- M. A. Ilyashov
The article contains the results of application in a coal mine of a combined way for protection and support of development workings. This method combines a frame support, anchors and a cast support strip erected behind the longwale. The geomechanical substantiation of technological parameters, regulations and the field for efficient use of this method are given. Its introduction has allowed to increase the loads on longwale and to lower labour content and expenses for maintenance of butt entries.
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Date submitted2009-08-25
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Date accepted2009-10-24
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Date published2010-02-01
Geomechanical substantiation of parameters of the fastening of railway tunnels in the conditions of the North Caucasus
- Authors:
- N. A. Belyakov
The article presents the rationale of temporary supports used in the drilling of new mines, which provides for the construction of model projects of reconstruction of old tunnels. Finite-element method analyzed the changes of stress-strain state containing tunnel complex array during the drilling of new mines. Based on the analysis, a number of findings to explore the possibility of reducing the thickness of the permanent support of new mines in tunnel complex - the new tunnel, and transport and drainage culvert.
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Date submitted2009-08-22
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Date accepted2009-10-19
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Date published2010-02-01
The substantiation of reinforcing support of preparation mines in the ore massive of the Yakovlevskiy deposit
- Authors:
- Yu. N. Antonov
- V. Yu. Sinegubov
The paper justifies a design of reinforcing mine support of the protective roof at the priority high-grade ore mining site of the Yakovlevskiy deposit. Experience of mine roadway support with the KMP-A3 standing support has been analyzed. A reinforcing support is offered consisting of rock bolts back bracing the ore exposure, which best fits with continuous miner roadheading and consolidating stowing (concrete).
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Date submitted2009-07-17
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Date accepted2009-09-22
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Date published2010-04-22
MINEFRAME is the modern tool for mining maintenance
- Authors:
- L. S. Lomako
- G. G. Korol
Today an automation of the basic technological processes in production is successfully introduced into various sectors of the national economy, including in mining practice. One of the modern software products intended for automated planning, designing and support of works at the mining enterprises, is integrated package – MINEFRAME which is put in industrial operation.
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Date submitted2009-07-28
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Date accepted2009-09-21
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Date published2010-04-22
Legislation-legal and normative-technical support of the utilization of the earth's interior
- Authors:
- V. S. Zimich
- M. P. Vasilchuk
The article considers the aspects of the legislation-legal and normative-technical support of the Earth's interior utilization. It is noted that mineral resources in Russia appear to be the basic source for the economic development. It is shown that there is no due attention to the development of the normative-methodological base of the Earth's interior utilization.
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Date submitted2009-07-19
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Date accepted2009-09-11
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Date published2010-04-22
Calculation of supports of parallel workings divided with yieldable pillars at anthracite seams
The article presents the methods for calculation of supports of parallel workings divided with yieldable pillars at anthracite seams. Consideration is given to the development of experimental data card for protection and maintenance of paired conveyor entries with using the steelpolymer anchor supports.
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Date submitted2009-07-02
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Date accepted2009-09-30
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Date published2010-04-22
Improved light-weight support types in mine workings
- Authors:
- V. A. Smirnov
- A. E. Khlusov
- B. N. Samorodov
A wider introduction of the efficient light-weight support types into practice, as compared with heavy support, allows to reduce by several times the material capacitance and labour costs in maintenance of stability of mine workings. New types of supports and their parameters have been considered and their application was substantiated.
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Date submitted2009-07-29
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Date accepted2009-09-15
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Date published2010-04-22
Preconditions for application of supports of different types in productive workings of low-thick gently-pitching deposits in tectonically stressed massif (for conditions of the Karnasurt ore mine)
- Authors:
- A. V. Lovchikov
- A. V. Matytsyn
The paper presents the data on the mining-geological conditions for mining and types of stope supports applied at the Karnasurt Mine, the Lovozersky rare-metal deposit. The peculiar feature of mining conditions is the presence of high subhorizontal tectonic stresses in the rock masses, which make the stope roofs more stable, allowing application of non-reinforced types of support.
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Date submitted2009-07-08
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Date accepted2009-09-19
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Date published2010-04-22
Geomechanical and hydrogeological problems оf the Yakovlevsky deposit development
- Authors:
- V. L. Trushko
- A. G. Protosenya
- R. E. Dashko
The article deals with geomechanical and hydrogeological problems under the Yakovlevsky ore deposit development including variations in strength properties. The estimation of feasible underground water inrush inside the mining excavation is done. In situ results of ore strata deformation around excavation are discussed. Numerical modeling of stress and strain in the waterproofing ore pillar due to partially backfilling of excavation is carried out.
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Date submitted2008-11-25
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Date accepted2009-01-02
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Date published2009-12-11
Principles and methods of constructing models of contract bidding in outsourcing support-service production
- Authors:
- N. G. Voronov
We consider the principles and methods of construction contract bidding in outsourcing support-service production by the criterion of optimality of the customer, implemented with a minimum expenditure of the funds and ensure the reduction of the cost of production customers.
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Date submitted2008-10-21
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Date accepted2008-12-12
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Date published2009-12-11
Assessment of stress-strain state of temporary support during constructhion of station tunnels of the metro
- Authors:
- V. A. Maslak
In-situ testing technique of temporary support is given. The values of stress and normal force in arch and sides of steel support are shown. Determination of vertical load magnitude is done. It was determined that vertical load on support decreases by 1,54 times, if lag of support installation from the face is16 m.
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Date submitted1951-07-11
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Date accepted1951-09-18
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Date published1952-12-23
Development of thin and medium-thickness rotating seams without the use of timber supports
- Authors:
- E. Ya. Makhno
The main disadvantage of the existing methods of developing thin and medium-thick steep coal seams is the use of wooden supports in the working faces. Support of the working faces is carried out exclusively by hand and is the most dangerous, difficult and labor-intensive operation. Thus, labor costs for support, timber delivery and control of rock pressure usually make up 50 to 80% of the total labor costs in the working face (see article). A miner spends about two thirds of the net working time on support. If we also take into account timber delivery and work on managing rock pressure (installation of organ support, etc.), then the total time spent on these operations, including support, will amount to approximately 80% of the total labor costs in the working face for coal mining. In the Donbass, chipping hammers are predominantly used, which determines a significantly higher labor intensity of coal mining work. Therefore, work related to support and rock pressure control here makes up approximately 50-60% of the total labor costs in the working face. But in the future, in connection with the introduction of combines, the specific weight of these works will increase significantly and will also reach 80-85%.