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Date submitted2024-09-09
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Date accepted2024-11-05
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Date published2024-11-12
Acoustic emission criteria for analyzing the process of rock destruction and evaluating the formation of fractured reservoirs at great depths
In order to study the mechanism of destruction of rocks of various genesis and the formation of fractured reservoirs at great depths, laboratory studies of rock samples in the loading conditions of comprehensive pressure with registration of acoustic emission (AE) and parameters of the process of changing the strength and deformation properties of samples were carried out. The spatial distributions of the hypocenters of AE events for each sample were investigated. By the nature of the distributions, the fracture geometry is described, then visually compared with the position of the formed macrofractures in the samples as a result of the tests. The time trends of the amplitude distribution b, set by the Guttenberg – Richter law, were calculated, which were compared with the loading curves and trends of the calculated AE activity. Based on the analysis of the AE process for three types of rocks – igneous (urtites), metamorphic (apatite-nepheline ores), and sedimentary (limestones) – parameterization of acoustic emission was carried out to determine the features of the deformation process and related dilatancy. As a result, three types of destruction of samples were identified, their geometry and changes in strength and seismic criteria were established.
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Date submitted2021-06-08
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Date accepted2021-11-30
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Date published2021-12-27
Management of groundwater resources in transboundary territories (on the example of the Russian Federation and the Republic of Estonia)
Groundwater, as a source of water supply, the most important mineral and geopolitical resource, , is often the only source of high-quality drinking water that is protected from pollution under conditions of increasing deterioration of surface water quality. Transboundary groundwaters are the focus of hydrogeological researchers for a number of reasons, including the reduction and pollution of water resources as a result of economic activities. The increased controversy between states over transboundary water issues has necessitated the development of international legal documents on issues related to water conflict prevention and the sustainable use of fresh water. As part of the analysis of the problem of legal regulation of groundwater extraction from transboundary aquifers and complexes, it is proposed to consider this aspect on the example of Russia. The problems of regulation of rational use and protection of fresh water in the bilateral treaties of the Russian Federation were revealed; a methodology for the management of groundwater extraction in the territory of the transboundary aquifer was developed, the size, parameters, and factors influencing the formation of the transboundary zone have been determined (based on research and analysis of water intake activities in the border areas of the Russian Federation and the Republic of Estonia) were determined.
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Date submitted2021-03-31
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Date accepted2021-09-29
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Date published2021-10-21
Methodology of modeling nonlinear geomechanical processes in blocky and layered rock masses on models made of equivalent materials
- Authors:
- Boris Yu. Zuev
The research purpose is to develop a methodology that increases the reliability of reproduction and research on models made of equivalent materials of complex nonlinear processes of deformation and destruction of structured rock masses under the influence of underground mining operations to provide a more accurate prediction of the occurrence of dangerous phenomena and assessment of their consequences. New approaches to similarity criterion based on the fundamental laws of thermodynamics; new types of equivalent materials that meet these criteria; systems for the formation of various initial and boundary conditions regulated by specially developed computer programs; new technical means for more reliable determination of stresses in models; new methods for solving inverse geomechanical problems in the absence of the necessary initial field data have been developed. Using the developed methodology, a number of complex nonlinear problems have been solved related to estimates of the oscillatory nature of changes in the bearing pressure during dynamic roof collapse processes; ranges of changes in the frequency of processes during deformation and destruction of rock mass elements, ranges of changes in their accelerations; parameters of shifts with a violation of the continuity of the rock mass under the influence of mining: secant cracks, delaminations, gaping voids, accounting for which is necessary to assess the danger of the formation of continuous water supply canals in the water-protection layer.
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Date submitted2020-10-26
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Date accepted2021-07-28
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Date published2021-10-21
Investigation of the influence of the geodynamic position of coal-bearing dumps on their endogenous fire hazard
The paper investigates the hypothesis according to which one of the factors influencing the spontaneous combustion of coal-bearing dumps is its geodynamic position, i.e. its location in the geodynamically dangerous zone (GDZ) at the boundary of the Earth crust blocks. This hypothesis is put forward on the basis of scientific ideas about the block structure of the Earth crust and the available statistical data on the location of burning dumps and is studied using computer modeling. A dump located in the area of Eastern Donbass was chosen as the object of research. The simulation results show that the penetration of air into the dump body from the mine through the GDZ, which crosses the mining zone, is possible at an excess pressure of 1000 Pa created by the main ventilation fans. The fire source appearance in the dump body causes an increase in the temperature of the dump mass and becomes a kind of trigger that "turns on" the aerodynamic connection between the dump and the environment, carried out through the GDZ. It is concluded that the establishment of an aerodynamic connection between the mine workings and the dump through the GDZ can be an important factor contributing to the endogenous fire hazard of coal-bearing dumps. The simulation results can be used in the development of projects for monitoring coal-bearing dumps and measures to combat their spontaneous combustion.
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Date submitted2019-04-30
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Date accepted2019-07-16
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Date published2019-10-23
Salt Rock Deformation under Bulk Multiple-Stage Loading
- Authors:
- I. L. Pankov
- I. A. Morozov
The paper presents experimental justification of the possibility to use bulk multiple-stage loading to study the process of salt rock deformation in the laboratory conditions. Results of comparative tests between bulk multiple- stage and single-stage loading of salt rock samples are demonstrated. The paper contains results of research on the rate of lateral pressure and its impact on strength limit and residual strength limit of sylvinite, estimated using single- stage and multiple-stage methods. Research results demonstrate how the rate of lateral pressure impacts dilatancy boundary of salt rocks. Analysis of how the loading method influences certificate parameters of Mohr-Coulomb strength of sylvinite has been carried out. The dynamics of elastic modulus in the process of salt rock deformation is analyzed depending on the rate of lateralpressure. It is demonstrated how the method of multiple-stage loading adequately reflects the processes of salt rock de- formation and decomposition, and facilitates not only lowering impact of sample’s inner structure heterogeneities on the experimental results, but also significant reduction in the required amount of rock material.
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Date submitted2018-09-22
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Date accepted2018-11-08
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Date published2019-02-22
Creation of temperature inhomogenities with the use of Peltier element for the mass-exchange processes intensification of the oil and gas industry
- Authors:
- V. G. Afanasenko
- Yu. L. Yunusova
The intensification of technological processes in the oil and gas industry is an urgent task for industrial production. Improving the efficiency of the processes leads to a decrease in the consumption of materials by the apparatus and the cost of their manufacture, an improvement in the quality of the produced product, and simplifies the transportation and installation of equipment. To achieve these goals, a new highly efficient equipment is being developed based on the use of various physical and chemical phenomena, their combinations, and new technological approaches. One of the most effective ways to solve such problems is pulse impact on the materials being processed, in which inhomogeneities of the process driving force are artificially created. The challenge of intensifying the processes occurring during the direct contact of the phases is the need to influence the system being processed locally - in the area of the interface, since it is there that the substances transfer from one phase to another. The object of article's scientific research – mass-exchange process, which is most widespread in oil and gas technology. As a model, the process of liquid evaporation is chosen, on which the separation of mixtures by rectification is based – the main process of the oil and gas processing industry. The heterogeneity of the driving force of the mass transfer process was created using a thermoelectric converter, the principle of which is based on the Peltier effect, in a series of experiments. Such converters allow creation of higher temperature gradient and, consequently, a greater temperature heterogeneity in the investigated system compared with traditional resistance electric heaters at the same energy expenditure. The article discusses the influence of the temperature inhomogenities location on the efficiency of mass-exchange processes, specifically the evaporation process. In experimental studies, the evaporation rate was estimated by measuring the mass evaporation velocity of a liquid. It is noted that the creation of a temperature gradient on the free surface of the liquid phase using a Peltier element with a specific power of 1.8 kW/m 2 leads to a twofold intensification of the evaporation process.
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Date submitted2015-07-14
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Date accepted2015-09-09
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Date published2016-02-24
Engineering and geomechanical forecast for waste disposal in underground caverns including earthquake-prone zones
- Authors:
- O. V. Kovalev
The article aims at obtaining representative scientifically based data to determine parameters of a necessary-safe condition of the rock massif (RM) in underground waste diposal caverns zones, including earthquake-prone zones. The main requirements for underground caverns for hazardous waste disposal and for their construction technology are described. The subject of the research is underground solution caverns in halogen rocks. Data for justification of safe waste disposal conditions in underground salt caverns and its stages are presented. A complex approach to the solution of the research problem is described. The main aspects of dynamic influence of seismic waves on underground caverns stability are considered. Taking into account seismic-risk zoning data on the research region some significant parameters of a possible seismic impact on the experimental cavern are calculated. The article points out the necessity of superincumbent rock and surface displacement assessment for the experimental site zone using the suggested complex approach and including the analysis of surveying data and results of rock mass geomechanical modeling.
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Date submitted2014-12-20
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Date accepted2015-02-05
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Date published2015-12-25
Synergetic changes of tribochemical properties in the heterogeneous systems containing surface modified metals
- Authors:
- A. G. Syrkov
In the article tribochemical properties and synergetic effects in lubricants with metal addi-tives, characterized by surface modifcations, have been analysed. The priority results of measur-ings friction coefficient (f) and friction force (F fr) are given for heterogeneous systems in the form of И-20 oil with solid Al-additives, contatiing dispersed aluminium, with surface-modified triamon (Т), alkamon (A) and ethylhydridsiloxane according to various programs. It has been educed that with all other things being equal, triamon underlayers introduction into Al-additives with the external chemisorpted ethylhydridsiloxane layer results in the decrease of F fr and f in the system in proportion to the Т-underlayer number reduction from three to one. It has been discovered that the use of low-molecular Т-underlayer in Al-additives is a delicate method of summand value regulation (from 10,8 to 13,2 Н), accountable for intermolecular forces in the boundary fritction equation in the tribological pair applied.
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Date submitted2013-07-23
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Date accepted2013-09-11
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Date published2014-03-17
Use of coefficient of output at pit delimitation
- Authors:
- G. A. Kholodnyakov
- N. S. Vainonen
In work it is settled an invoice the final depth of a pit of the conditional complex occurrence presented by three minerals. It is shown that when developing complex occurrence it is more expedient to use coefficient of output, instead of overburden ratio.
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Date submitted2009-09-12
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Date accepted2009-11-03
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Date published2010-06-25
One variant of boundary element method application to calculation of bearing pressure on conditions to coal and salt deposits
- Authors:
- L. A. Bespalov
- A. P. Gospodarikov
The analysis of stress-strain state near excavations was carried out in this work as applies to coal and salt deposits. The indirect boundary element method was used as a tool of research.
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Date submitted2009-08-02
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Date accepted2009-10-10
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Date published2010-02-01
The analyses of influence of goafs on the state of developmental excavations as applies to Starobinsky potassium salt deposit
- Authors:
- A. P. Gospodarikov
- L. A. Bespalov
The analysis of stress-strain state near excavations and influence of goafs on its redistribution were carried out in this work as applies to coal and salt deposits. The indirect boundary element method was chosen as a tool of research.