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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 submitted2022-05-20
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Date accepted2023-06-20
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Date published2024-02-29
Increasing the quality of zeolite-bearing rocks from Eastern Transbaikalia by applying directed energy
This paper presents the use of accelerated electrons to treat zeolite-bearing rocks from Eastern Transbaikalia to increase the efficiency of separating zeolites from rock-forming minerals via electromagnetic separation. The effectiveness of the liberation of zeolite minerals using accelerated electrons was analyzed. The results of dry electromagnetic separation of zeolite-bearing rocks are presented. The dependence of the extraction of iron-bearing minerals from zeolite-bearing rocks by electromagnetic separation on the magnetic field intensity for different particle sizes has been established. The main methods of zeolite-bearing rock enrichment and ore preparation were determined. A technological scheme for processing zeolite-bearing rocks, based on the use of accelerated electron treatment at the ore preparation stage, is presented, significantly improving the zeolite production quality.
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Date submitted2020-06-22
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Date accepted2020-07-24
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Date published2020-06-30
Methods for assessing the technical compatibility of heterogeneous elements within a technical system
The article provides methods for assessing the compatibility of elements in the design of complex technical systems. The compatibility of the elements is considered as the main indicator that determines the quality of systems including heterogeneous elements. The presented methods make it possible at the design stage to choose a technical solution that is most suitable for the project objectives, taking into account the operating conditions of the system. The methods make it possible to evaluate compatibility by a single and complex indicator. The choice of indicator depends on the purpose of the assessment. An example of methods implementation in the design of systems including an electric drive and pipeline shutoff valves is considered. It has been experimentally proved that in systems with low values of the compatibility level, the actual power characteristics exceed the required values, which leads to additional voltages in the system elements and their breakdowns. The results of the assessment of typical systems allowed to identify the shortcomings of existing structures and propose alternative solutions to problems. The compatibility of elements within the framework of a technical system makes it possible to increase the functional efficiency of systems with minimum weight and size and power characteristics, to optimize the price-quality ratio, and to increase the competitiveness of the final product.
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Date submitted2019-05-14
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Date accepted2019-07-05
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Date published2020-04-24
Development of spacer fluids and cement slurries compositions for lining of wells at high temperatures
Article is devoted to creation of new compositions of process solutions for lining of directional wells at high temperatures. Developed compositions provide high durability characteristics of cement stone. It is shown that with an increase in packing density of cementing slurry components durability characteristics increase and porosity and permeability of cement stone decrease, whereas an increase in temperature and pressure leads to a significant increase in compressive and bending durability, which is associated with presence of quartz in them. It has been established that introduction of special structure-forming additives to the composition of developed cementing solutions allows formation of sedimentation-resistant cement systems that can provide an increase in durability characteristics of cement stone and, in general, quality lining of directional wells. Study of rheological properties of developed cementing compositions showed that the systems have high yield strength at increased temperatures and pressures. Developed compositions of water-based spacer fluids increase the cleansing degree for both casing and rocks surfaces from mud and clay cake residues, which improves the cementing quality of oil and gas wells. Mechanism for increasing the washing ability of spacer fluids and durability characteristics of cement stone, depending on composition and properties of their constituent components, is disclosed.
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Date submitted2019-03-17
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Date accepted2019-05-13
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Date published2019-08-23
Manifestations of Acoustic Emission in Frozen Soils with Simultaneous Influence of Variable Mechanical and Thermal Effects on Them
- Authors:
- E. A. Novikov
- V. I. Shkuratnik
- M. G. Zaytsev
The subject of the research is to establish the fundamental laws of acoustic emission in frozen soils, which allow to create ways to control (monitor) their stability under the influence of variable temperature fields and quasistatic mechanical stress from engineering objects located on these grounds for various purposes. The applied importance of such methods is to increase the speed and reduce the complexity of engineering geological surveys in the northern regions of Russia, carried out with the aim of predicting the loss of stability of the bases of buildings and structures to ensure their safe operation. The study was performed on the original instrumental complex. Its description and characteristics are given. With the use of this complex, thermoacoustic emission effects arising from the repeated alternation of freezing and thawing cycles of the soil during the development of its deformed state, starting from the normal compaction phase and up to the final stage of destruction (the bulging phase), have been studied. It is shown that on the basis of such informative parameters as thermally stimulated activity and duration of acoustic emission pulses, an indicator can be obtained that quantitatively characterizes the stages of the stress-strain state of soils. An experimental dependence of the field of values of this indicator as a function of the mechanical stress and the fractional composition of the test soil is given. The qualitative convergence of this dependence with the classical soil deformation diagram obtained by N.M.Hersevanov is shown, where the stages of compaction, loss of stability (shifts) and destruction are highlighted. Possible physical mechanisms and features of the formation of an acoustic emission response at each of these stages are considered and substantiated. It is noted that the approaches to receiving, processing and interpreting acoustic emission measurement information, which are grounded within the framework of the study, allow to control and monitoring of the carrying capacity and stress-strain state of soils directly in the field.
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Date submitted2018-09-10
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Date accepted2018-11-06
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Date published2019-02-22
Comparative analysis of zincand tin oxidation with acids at room temperatures
- Authors:
- S. D. Pozhidaeva
- L. S. Ageeva
- A. M. Ivanov
The paper analyses the parameters of deep oxidation of zinc and tin by copper (II) compounds and molecular iodine in the presence of molecular oxygen and hydrogen peroxide, as second oxidizers working synchronously with them in various media (aqueous, aqueous-organic and organic) with the participation of mineral and carboxylic acids close to room temperature. The contribution of the reactivity of the metal to its rate of consumption, especially the average, is often much less than the contribution associated with the release characteristics of the working surface, determined by the rates of accumulation of surface deposits of metal oxidation products, their strength and adhesion characteristics their destruction and shifting into the bulk phase.
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Date submitted2015-08-13
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Date accepted2015-10-29
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Date published2016-04-22
Multicriteria estimation of bearing capacity of geomaterials
- Authors:
- I. A. Brigadnov
In the article the problem of an estimation of bearing capacity of geomaterials as a deform-able solid is considered in the current configuration, which may be as the reference (undeformed) or the actual (deformed). We propose an original variational approach to the problem for stresses in selected subdomains, in which, depending on different engineering considerations, average in-tegral values of different component of stresses are estimated and from their aggregate the bearing capacity of the current configuration of the solid is estimated regarding to given external influ-ences. In each of the selected subdomain the weakest stress field is obtained which is globally bal-anced with external influences. For example, the assessment of the average integral hydrostatic pressure is needed for study of bearing capacity of geomaterials.
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Date submitted2014-11-22
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Date accepted2015-01-01
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Date published2015-10-26
Theoretical and methodological bases of forming a program management system for integrated development of a region
- Authors:
- S. V. Fedoseev
- Sya Chzhan
This article deals with theoretical and methodological bases of forming a program manage-ment system for integrated development of a region. The idea of a program-based management system based on a system of socio-economic transformation is presented. The given bases include monitoring emerging trends in the program management for integrated development of a region of the Russian Federation on basic parameters and involve control of the management process. The concept of forming the mechanism of program management as an integrated system is suggested.
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Date submitted2009-08-05
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Date accepted2009-10-26
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Date published2010-02-01
The influence of change in geotechnical engineering and geoenvironmental conditions during the process of building and operation of constructions of projected Alekseevsky cement factory on their stability (Mordovia Republic)
- Authors:
- K. V. Pankratova
The influence of change engineering-geological and geoenvironmental conditions on stability of cement factory are considered in this paper. Influence of additional humidifying, rise in temperature in the basis of constructions and activization of microbic activity is considered. The specificity of physicomechanical properties of silica rock and upper Jurassic clay is considered. Results of experimental researches of increase in microbic mass in soils at watering and heating are resulted. The estimation influences of temperature on deformation ability soils is given.
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Date submitted2009-08-01
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Date accepted2009-10-29
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Date published2010-02-01
Increase of competitiveness of russian and belorussian potash companies owing to perfection of sale policy
- Authors:
- T. V. Ponomarenko
- A. N. Sultani
The potassium companies of Russia and Belorussia, developing the unique deposits of potassium salts, provide more than 40 % of the world production of potassium fertilizers. Therefore economic efficiency from their activity considerably influences to the world market of potassium. Being the companies which export more than 80 % producible products «Belaruskali», «Uralkali» and «Silvinite» have problems with the transport of fertilizers in Brazil, India, China. Therefore for the increase of competitiveness of these enterprises it is necessary to develop an effective logistic chain which would take into account their geopolitical features.
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Date submitted2008-11-25
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Date accepted2009-01-02
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Date published2009-12-11
Management of competitiveness of the enterprise in crisis
- Authors:
- A. V. Kichigin
- V. S. Vasiltsov
Feature of anti-recessionary management of the organisation consists in the raised complexity of administrative processes. Financial crisis is shown in shortage of money resources, growth of the delayed creditor debts, falling of sales, discontent of the personnel and other adverse factors. Level of requirements to the heads, making the most important, strategic decisions, increases in a geometrical progression In the conditions of a crisis state most important to reduce one expenses and to increase others which can make the company profitable.
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Date submitted2008-11-13
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Date accepted2009-01-01
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Date published2009-12-11
The quality of commodity output – the factor of competitiveness iron-ore branch
- Authors:
- R. V. Korchenkov
The problems of quality improving of commodity output are the most urgent and up-to date questions in the period of intromission of Russian on the world market. The country possesses of significant mineral raw ferrous materials, which are poor quality. In conjunction with it mining-and-processing integrated works must develop and improve the process of production in order to provide the quality of the products conforming to world requirements. The main task of iron-ore branch in Russia is to maintain the competitive ability on the foreign market.
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Date submitted2008-11-28
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Date accepted2009-01-20
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Date published2009-12-11
Model of evaluation of the mining enterprise’s competitiveness’ potential
- Authors:
- T. V. Ponomarenko
- A. N. Sultani
Competitiveness of a mining enterprise has a dynamic character which defines a necessity to evaluate a potential of competitiveness at the moment and in the future. The evaluation of competitiveness’ potential has to be systematic, to engulf different levels which are differentiated by interval of evaluation, information sources, evaluation base, methods and results. The method of evaluation of basic indices of competitiveness’ potential is presented in this paper. The calculation of operation and dynamic competitiveness’ potential of JSC “Uralkali” and JSC “Silvinit” for 2007 year was made and the interpretation of received results was given.
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Date submitted2008-10-30
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Date accepted2008-12-22
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Date published2009-12-11
Investigations of the mechanism of methane desorption in coal saturation with carbon dioxide
- Authors:
- A. T. Karmansky
The article considers the developed unit for investigations of interaction between coal and gas, and gas outflow from the coal surface by gravimetric method under gas pressure up to 6 MPa. Relationship between the sorption ability and metamorphism stage is explained by the microstructure of coal. The adsorption increment indices of volume V and velocity of changes in pressure P – during adsorption may be used for prediction of outburst-hazard of coal and gas.