-
Date submitted2023-09-29
-
Date accepted2023-10-25
-
Date published2024-08-26
Laboratory studies of transformation of porosity and permeability and chemical composition of terrigenous reservoir rocks at exposure to hydrogen (using the example of the Bobrikovskii formations in the oil field in the northeast Volga-Ural oil and gas province)
The article describes the methodology for laboratory studies of reservoir rock exposure to hydrogen. The stages of sample research and the instruments used in the experiments are considered. A comparative analysis of the results of studies on porosity and permeability of core samples was performed. It was shown that after exposure to hydrogen, the porosity decreased by 4.6 %, and the permeability by 7.9 %. The analysis of correlation dependencies demonstrated a typical change in the relationship of these characteristics: after the samples exposure to hydrogen the scatter of the values increased and the correlation coefficient decreased, which indicates a change in the structure of the void space. Based on the research results, it was concluded that the decrease in porosity and permeability of the core samples occurred due to their minor compaction under the action of effective stresses. The chemical analysis of the rock showed no major difference in the composition of the basic oxides before and after exposure to hydrogen, which points to the chemical resistance of the studied formation to hydrogen. The experimental results showed that the horizon under consideration can be a storage of the hydrogen-methane mixture.
-
Date submitted2023-06-01
-
Date accepted2024-03-05
-
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.
-
Date submitted2023-07-27
-
Date accepted2024-06-03
-
Date published2024-12-25
Normalized impulse response testing in underground constructions monitoring
Impulse Response testing is a widespread geophysical technique of monolithic plate-like structures (foundation slabs, tunnel lining, and supports for vertical, inclined and horizontal mine shafts, retaining walls) contact state and grouting quality evaluation. Novel approach to data processing based on normalized response attributes analysis is presented. It is proposed to use the energy of the normalized signal calculated in the time domain and the normalized spectrum area and the average-weighted frequency calculated in the frequency domain as informative parameters of the signal. The proposed technique allows users a rapid and robust evaluation of underground structure’s grouting or contact state quality. The advantage of this approach is the possibility of using geophysical equipment designed for low strain impact testing of piles length and integrity to collect data. Experimental study has been carried out on the application of the technique in examining a tunnel lining physical model with a known position of the loose contact area. As examples of the application of the methodology, the results of the several monolitic structures of operating municipal and transport infrastructure underground structures survey are presented. The applicability of the technique for examining the grouting of the tunnel lining and the control of injection under the foundation slabs is confirmed. For data interpretation the modified three-sigma criteria and the joint analysis of the attribute’s behavior were successfully used. The features of the field work methodology, data collection and analysis are discussed in detail. Approaches to the techniques' development and its application in the framework of underground constructions monitoring are outlined. The issues arising during acoustic examination of reinforced concrete plate-like structures are outlined.
-
Date submitted2022-10-29
-
Date accepted2023-10-25
-
Date published2024-04-25
Assessment of rock massif sustainability in the area of the underground research laboratory (Nizhnekanskii Massif, Enisei site)
The study presents the results of the research on geodynamic and geological conditions of the Enisei site (Krasnoyarsk Krai), chosen for the construction of an underground research laboratory. The laboratory is being built at a depth of 500 m to assess the suitability of the rock mass for burying high-level radioactive waste. The rocks consist of weakly fractured gneisses, granites, and dikes of metadolerites. Field observations were conducted on bedrock outcrops. They included the determination of rock mass quality indicators, measurement of rock fracturing, and a rating classification of stability using N.Barton's method. GNSS observations were also made to monitor surface deformations. These data were used to develop a three-dimensional structural model, including lithology, fault disruptions, intrusive bodies, elastic-strength properties of rocks, and the sizes of zones influenced by faulting. It will serve as a basis for boundary conditions and the construction of three-dimensional variational models of stress-strain states, identifying zones of concentration of hazardous stresses, and planning in situ geomechanical experiments in underground mines of the laboratory. The obtained values of the modified QR index for the main types of rocks allowed their classification as stable and moderately stable, corresponding to strong and very strong rocks on Barton's scale and the massif rating according to geomechanical classification.
-
Date submitted2021-05-12
-
Date accepted2022-05-11
-
Date published2023-07-19
Application of the cybernetic approach to price-dependent demand response for underground mining enterprise electricity consumption
The article considers a cybernetic model for the price-dependent demand response (DR) consumed by an underground mining enterprise (UGME), in particular, the main fan unit (MFU). A scheme of the model for managing the energy consumption of a MFU in the DR mode and the implementation of the cybernetic approach to the DR based on the IoT platform are proposed. The main functional requirements and the algorithm of the platform operation are described, the interaction of the platform with the UGME digital model simulator, on which the processes associated with the implementation of the technological process of ventilation and electricity demand response will be simulated in advance, is shown. The results of modeling the reduction in the load on the MFU of a mining enterprise for the day ahead are given. The presented solution makes it possible to determine in advance the necessary power consumption for the operation of the main power supply unit, manage its operation in an energy-saving mode and take into account the predicted changes in the planned one (e.g., when men hoisting along an air shaft) and unscheduled (e.g., when changing outdoor air parameters) modes. The results of the study can be used to reduce the cost of UGME without compromising the safety of technological processes, both through the implementation of energy-saving technical, technological or other measures, and with the participation of enterprises in the DR market. The proposed model ensures a guaranteed receipt of financial compensation for the UGME due to a reasonable change in the power consumption profile of the MFU during the hours of high demand for electricity, set by the system operator of the Unified Energy System.
-
Date submitted2022-04-03
-
Date accepted2023-03-02
-
Date published2023-12-25
Specifics of geotechnical risk control in the design of underground structures
The underground space development is associated with the emergence of complex and dangerous situations, often leading to accidents. The condition for their development is the potential geotechnical risks. High-quality execution and analysis of design work at all the stages of design, starting from the early stages, is one of the effective ways to control risks. Clarification of the characteristics and features of the rock mass adjacent to the projected underground structure makes it possible to identify the potential cause of the occurrence of an adverse event with a certain probability during the construction and operation of an underground structure. The purpose of a qualitative risk analysis is to identify risk factors in underground construction. The value of the total geotechnical risk, expressed by the sum of each of the possible risks, should be numerically estimated at the design stage of a specific underground facility. At the same time, it is extremely important to develop a methodology for managing geotechnical risks, which would make it possible to assess their probability of development at an early stage of project preparation and propose measures to reduce or prevent them. This technique is given in the article. The results of the study conducted in accordance with the presented methodology showed that geotechnical risk control proved an effective method in preventing accidents during underground construction.
-
Date submitted2021-10-31
-
Date accepted2023-03-02
-
Date published2023-12-25
Improvement of technological schemes of mining of coal seams prone to spontaneous combustion and rock bumps
On the example of the Alardinskaya mine, the problem of underground mining of seams prone to spontaneous combustion and rock bumps in the conditions of the Kondomsky geological and economic region of the Kuznetsk coal basin is considered. The contradictions in the requirements of regulatory documents for the width of the inter-panel coal pillars in the mining of seams with longwalls in conditions of endogenous fire hazard and in the mining of seams that are dangerous due to geodynamical phenomena are discussed. These contradictions impede the safe mining of seams using traditionally used layouts with the danger of spontaneous combustion of coal and rock bumps. A mining-geomechanical model is presented, which is used for numerical three-dimensional simulation of the stress-strain state of a rock mass with various layouts for longwall panels using the finite element method. The results of the numerical analysis of the stress state of the rock mass immediately before the rock bump are presented, and the main factors that contributed to its occurrence during the mining of the seam are established. A dangerous degree of stress concentration in the coal seam near the leading diagonal entries is shown, especially in conditions of application of abutment pressure from the edge of panels’ gob. The analysis of the features of stress distribution in the inter-panel pillar at different widths is carried out. Recommendations for improving the layout for the development and mining of coal seams that are prone to spontaneous combustion and dangerous in terms of rock bumps in the conditions of Alardiskaya mine have been developed. The need for further studies of the influence of pillars for various purposes, formed during the mining of adjacent seams, on the stress-strain state of previously overmined and undermined seams is shown.
-
Date submitted2022-10-17
-
Date accepted2023-02-13
-
Date published2023-04-25
Environmental geotechnology for low-grade ore mining with the creation of conditions for the concurrent disposal of mining waste
Due to the constantly deteriorating environmental situation in the regions with mining enterprises, the article considers the topical issue of disposing the maximum possible volume of waste from the mining and processing of low-grade ferrous ores through the creation of an effective underground environmental geotechnology. Traditional procedure with descending mining of reserves with a caving system does not allow waste to be disposed of in a gob. The idea is to use geotechnology based on the ascending order of mining the ore body, room excavation, leaving truncated pillars, and staggered arrangement of adjacent rooms in height, which makes it possible to form containers for waste disposal in the form of a cementless backfill. The main characteristics of the proposed procedure are investigated and compared with the traditional procedure of low-grade iron ores mining. It was established that from the point of view of the complete extraction of reserves and the unit costs for the preparatory-development operations, the processes are comparable, while in terms of the mining quality, the proposed option is much more efficient. Evaluation of environmental geotechnology by the criterion of waste disposal, performed according to the proposed methodology, showed that the combination of these technical solutions ensures the placement in the formed gob from 80 to 140% of all waste generated during the mining and beneficiation of low-grade iron ores.
-
Date submitted2021-07-05
-
Date accepted2022-01-24
-
Date published2022-04-29
Ensuring the excavation workings stability when developing excavation sites of flat-lying coal seams by three workings
- Authors:
- Oleg I. Kazanin
- Andrei A. Ilinets
On the basis of analysis of mining plans and field studies at mines of JSC SUEK-Kuzbass, it is shown that in conditions of increasing the size of excavation columns during the development of flat-lying coal seams the stress-strain state of the rock mass along the workings length changes significantly. The necessity of predicting the stress-strain state at the design stage of the workings timbering standards, as well as subsequent monitoring of the workings roof state and its changes in the mining operations using video endoscopes, is noted. The results of numerical studies of the stress-strain state of the rock mass during the development of excavation sites by three workings for various combinations of width of the pillars between the workings for mining-geological and mining-technical conditions of the “Taldinskaya-Zapadnaya-2” mine are provided. The stresses in the vicinity of the three workings are compared with the values obtained during the development of the excavation sites by double drift. A set of recommendations on the choice of the location of the workings, the width of pillars, timbering standards that ensure the stable condition of the workings throughout the entire service life at the minimal losses of coal in the pillars is presented.
-
Date submitted2021-06-15
-
Date accepted2021-08-27
-
Date published2021-10-21
Prospects for the use of modern technological solutions in the flat-lying coal seams development, taking into account the danger of the formation of the places of its spontaneous combustion
- Authors:
- Vladimir P. Zubov
- Dmitrii D. Golubev
Spontaneous combustion of coal remains an important problem for coal mines, which can lead to an explosion of methane and coal dust. Accidents associated with spontaneous combustion of coal can cause significant economic losses to coal mining companies, as well as entail social damage – injuries and loss of life. Accidents are known at the Kuzbass mines, which occurred as a result of negligent attitude to the danger of spontaneous combustion of coal, the victims of which were dozens of people. The analysis of emergency situations associated with spontaneous combustion of coal shows that the existing wide range of means of preventing endogenous fires does not provide complete safety when working out coal seams prone to spontaneous combustion, therefore, spontaneous combustion places continue to occur in mines. The consequences that may arise as a result of a methane explosion initiated by a self-ignition place indicate the need to improve the used technologies. The purpose of the work is to determine the impact of modern technological solutions used in functioning mines during underground mining of flat-lying coal seams prone to spontaneous combustion, and to develop new solutions that reduce endogenous fire hazard. Conclusions on the influence of leaving coal pillars in the developed space, isolated air removal from the stoping face through the developed space, the length of the stoping face and the excavation pillar, and other factors on the danger of the formation of spontaneous combustion places are presented. Conclusions about the possibility of using modern technological solutions in future are also drawn.
-
Date submitted2021-01-18
-
Date accepted2021-05-21
-
Date published2021-09-20
Improving the efficiency of the technology and organization of the longwall face move during the intensive flat-lying coal seams mining at the Kuzbass mines
The reasons for the lag of the indicators of the leading Russian coal mines engaged in the longwall mining of the flat-lying coal seams from similar foreign mines are considered. The analysis of the efficiency of the longwall face move operations at the JSC SUEK-Kuzbass mines was carried out. A significant excess of the planned deadlines for the longwall face move during the thick flat-lying seams mining, the reasons for the low efficiency of disassembling operations and the main directions for improving the technology of disassembling operations are revealed. The directions of ensuring the operational condition of the recovery room formed by the longwall face are considered. The recommended scheme of converged coal seams mining and a three-dimensional model of a rock mass to justify its parameters are presented. Numerical studies using the finite element method are performed. The results of modeling the stress-strain state of a rock mass in the vicinity of a recovery room formed under conditions of increased stresses from the boundary part of a previously mined overlying seam are shown. The main factors determining the possibility of ensuring the operational condition of the recovery rooms are established. It is shown that it is necessary to take into account the influence of the increased stresses zone when choosing timbering standards and organizing disassembling operations at a interbed thickness of 60 m or less. A sufficient distance from the gob of above- or undermined seams was determined to ensure the operational condition of the recovery room of 50 m, for the set-up room – 30 m. Recommendations are given for improving technology and organization of the longwall face move operations at the mines applied longwall mining of flat-lying coal seams with the formation of a recovery room by the longwall face.
-
Date submitted2021-01-21
-
Date accepted2021-02-24
-
Date published2021-04-26
Forecasting of mining and geological processes based on the analysis of the underground space of the Kupol deposit as a multicomponent system (Chukotka Autonomous Region, Anadyr district)
- Authors:
- Regina E. Dashko
- Ivan S. Romanov
The underground space of the Kupol deposit is analyzed as a multicomponent system – rocks, underground water, microbiota, gases (including the mine atmosphere) and supporting structures – metal support and shotcrete (as an additional type of barring) and also stowing materials. The complex of host rocks is highly disintegrated due to active tectonic and volcanic activity in the Cretaceous period. The thickness of sub-permafrost reaches 250-300 m. In 2014, they were found to contain cryopegs with abnormal mineralization and pH, which led to the destruction of metal supports and the caving formation. The underground waters of the sub-permafrost aquifer are chemically chloride-sulfate sodium-calcium with a mineralization of 3-5 g/dm 3 . According to microbiological analysis, they contain anaerobic and aerobic forms of microorganisms, including micromycetes, bacteria and actinomycetes. The activity of microorganisms is accompanied by the generation of hydrogen sulfide and carbon dioxide. The main types of corrosion – chemical (sulfate and carbon dioxide), electrochemical and biocorrosion are considered. The most hazardous is the biocorrosion associated with the active functioning of the microbiota. Forecasting and systematization of mining and geological processes are carried out taking into account the presence of two zones in depth – sub-permafrost and below the bottom of the sub-permafrost, where mining operations are currently underdone. The importance of assessing the underground space as a multicomponent environment in predicting mining and geological processes is shown, which can serve as the basis for creating and developing specialized monitoring complex in difficult engineering and geological conditions of the deposit under consideration.
-
Date submitted2020-11-16
-
Date accepted2021-03-02
-
Date published2021-04-26
Determination and verification of the calculated model parameters of salt rocks taking into account softening and plastic flow
The article suggests using a combination of the modified Burgers model and the Mohr – Coulomb model with the degradation of the adhesion coefficient and the increase in the friction coefficient to determine the parameters of salt rocks. A comparative analysis of long-term laboratory tests and field observations in underground mine workings with the results obtained using a calculated model with certain parameters is carried out. The parameters of the Mohr – Coulomb model with the degradation of the adhesion coefficient and the increase in the friction coefficient were obtained from the statistically processed data of laboratory tests, and the parameters of the modified Burgers model were determined. Using numerical methods, virtual (computer) axisymmetric triaxial tests, both instantaneous and long-term, were performed on the basis of the proposed model with selected parameters. A model problem is solved for comparing the behavior of the model with the data of observation stations in underground mine workings obtained from borehole rod extensometers and contour deformation marks. The analytically obtained coefficients of the nonlinear viscous element of the modified Burgers model for all the analyzed salt rocks did not need to be corrected based on the monitoring results. At the same time, optimization was required for the viscoelastic element coefficients for all the considered rocks. The analysis of the model studies showed a satisfactory convergence with the data on the observation stations. The comparative analysis carried out on the models based on laboratory tests and observations in the workings indicates the correct determination of the parameters for salt rocks and the verification of the model in general.
-
Date submitted2019-12-20
-
Date accepted2020-09-01
-
Date published2020-10-08
Features of the underground storages construction in depleted oil and gas condensate fields
The paper considers the features of the underground storages (US) construction in depleted oil and gas condensate fields (DOGCFs). The requirements for the structure of the formation, corresponding to the parameters of the object for possible US creation are presented. The influence of geological, hydrogeological, mining and technical rock formation conditions on the reliability and tightness of underground storages, including underground gas storages, has been evaluated. The necessary conditions for the US design are analyzed at the example of the Ach-Su oil and gas condensate field, in the presence of a well-explored trap with acceptable parameters for the construction of an underground storage. An important aspect is the geological conditions that meet the criteria for selecting the object: the required structure, the absence of fracturing faults, high reservoir properties of the formation, a sufficient volume of the deposit for the storage. Geological conditions lay the basis for determining the individual characteristics of the US construction technology at each DOGCF. The refined results for the current gas-saturated pore volume and the rate of pressure drop in the formation are presented, which makes it possible to select improved technological indicators in the course of operation of the created US. In order to select the optimal option for the design and construction of the US, the results of economic and geological scenarios analysis were studied concurrently with the capabilities of the technological operation of the object and transport system, which can ensure the maximum daily production of the storage.
-
Date submitted2020-06-12
-
Date accepted2020-06-12
-
Date published2020-06-30
Management of hardening mixtures properties when stowing mining sites of ore deposits
Underground mining is characterized by the weakening of the bearing rock mass strata competence and the accumulation of mineral waste. The full use of subsurface resources is ensured by the use of technologies with filling voids by hardening mixtures, which requires high-quality raw materials to obtain the required strength. The deficit of the binding component can be filled with the use of granulated slags of blast-furnace process, mill tailings, ash-slags and other wastes. Most often, voids are laid by mixtures with a combination of cement and a binding component. Mixtures with ash-slag additives to cement in an equivalent amount are not inferior to the strength of the mixture only with cement, especially when grinding ash-slag. The properties of stowing rock masses when using composite binding components and inert fillers are controlled by mechanical, chemical, physical and energy effects at the stages of preparation and transportation of hardening mixtures. To obtain the active fraction of cement substitutes, disintegrators are used that apply the inertia forces of materials at a high speed of rotation with an increase in high activity indicators and lower energy costs. The components of hardening mixtures can be the majority of waste from mining and related industries, which is determined experimentally in specific conditions.
-
Date submitted2020-05-05
-
Date accepted2020-05-24
-
Date published2020-06-30
Justification of stripping and development of a modular mine site for a combined coal mining method in Kuzbass on the example Baikaimskaya mine site
- Authors:
- Roman I. Shishkov
- Valerii A. Fedorin
The article considers one actual method for development coal deposits in the Kuzbass by open-underground mining. The scientific and practical advantages of the proposed method due to the use of common infrastructure of coal mine and a modular mine site (subsequently transformed into a mining and technological structure operating according to the mine – longwall scheme) are presented. Currently, a development strategy for Kuzbass until 2035 has been developed. As part of the strategy, a draft program for subsoil use is being formed in the coal industry department. The program should take into account all the positive and negative aspects associated with coal mining in cities and municipal areas and also their prospects. In the Kuznetsk coal basin, 42 mines and 52 opencast mines are mining, of which 12 enterprises use partially unified infrastructure. According to the results of open-underground mining work conducted by the laboratory of the Institute of Coal and Coal Chemistry of the Siberian Branch of the Russian Academy of Sciences (Institute of Coal SB RAS), the list of sites includes favorable mining and geological conditions with incidence angles of up to 18 degrees. As open-pit coal production increases, many sites encounter such a parameter as maximum allowable (boundary) strip ratio. At the stage of preparing the feasibility study for the development of a coal deposit, this coefficient is calculated first of all, since duration of enterprise’s work and its economic component depend on it. In order to increase parameters, it is necessary to carry out transition from open works to underground. As a result, coal mine will not work at a loss, providing production with an economically disadvantageous strip ratio.
-
Date submitted2020-05-06
-
Date accepted2020-05-24
-
Date published2020-06-30
Revisiting the evolution of deformation zones under platform conditions in the case study of the Kungur Ice Cave (Cis-Urals)
- Authors:
- Nataliya V. Lavrova
Observations in mining tunnels and caves allow to identify composition and development specifics of fault structures under subsurface conditions at various stages of geological history. Basing on the existing formation model of Kungur Ice Cave karst system, author examines the transformations of deformation zones, occurring in the mass of interlaid sulfate and carbonate rocks under platform conditions. Morphologic specifics of vertical structures – organ pipes, developed within one of the gypsum-anhydrite units, are defined by evolution stages of disjunctive faults, penetrating the entire rock mass of the Ice Cave. Point infiltration of surface waters and formation of a single channel, where rock softening and taluses from overlapping deposits gradually occur, are currently considered to be the initiators of pipe formation. At a later stage a sink forms on the surface, increasing the amount of water coming to the karsting mass. However, the size of debris in the talus, incommensurate with the pipe head, rounded arches of separate pipes, fragments of feeder channels, characteristic for artesian conditions of underground water circulation, faceted rock debris from overlapping deposits, specifics of wall structure all define the priority of pipe formation over grottos and cave galleries. Plastic properties of gypsum sediments and processes of their hydration define secondary modifications of pipe walls up to complete filling of the voids and formation of secondary pillars with subsequent renewed formation of vertical channels – significantly smaller in diameter and formed by infiltration waters when subject to corrosion.
-
Date submitted2019-05-26
-
Date accepted2019-07-23
-
Date published2019-10-23
Ensuring Stability of Undermining Inclined Drainage Holes During Intensive Development of Multiple Gas-Bearing Coal Layers
At high rates of production face advance, requirements towards reliable operation of undermining drainage holes get raised. The issue of maintaining high intensity of gaseous seams development under naturally increasing gas content, mining depth and capacity of production equipment poses a problem. The greatest threat comes from the loss of hole stability in the bearing pressure affected zone (in front of the face) and in the intensive shift area of overhanging rock corbels (behind the face). Intensification of air leaks due to deformation of borehole channel leads to impoverishment of removed methane-air mixture and an increasing risk to disturb safe aerogas regime in the mining area. The paper describes a mechanism of how coal-face operations affect the state of underground holes and formation of overhanging rock corbels. A typification of basic kinds of borehole deformations is presented. Authors point out critical disadvantages of the most widely-used technological schemes of gaseous seams development under high load on the production face, which hinder normal operation of a gas drainage system. As a result of research, a dependency of shot hole number, as well as the distance between shot hole axes and the borehole, on the stress state of the borehole outline has been defined more precisely. Basing on that, a formula to calculate drilling parameters of the discharge hole system has been suggested. Implementation of these measures will allow to increase the efficiency of underground gas drainage and to maintain growing intensity of gaseous coal seam development.
-
Date submitted2018-05-14
-
Date accepted2018-07-01
-
Date published2018-10-24
Method for forecast of surface deformation during excavation operations in restraint urban conditions using the slurry trench technique
- Authors:
- P. A. Demenkov
- L. A. Goldobina
- O. V. Trushko
The article suggests the method for forecast of surface deformation during excavation operations in restraint urban conditions using the slurry trench technique based on FEM simulation. The results of numerical simulation of the construction of a semi-underground structure with slurry trench technique are given. The regularities of the change in the stress-strain state are determined depending on the trench parameters and the physical-mechanical properties of the soils. The work presents the troughs of surface subsidence during the construction of an excavation using the slurry trench technique, the diagrams of bending moments, transverse and longitudinal forces arising in the trench. Numerical experiments in Plaxis 2D and 3D were performed to estimate the discrepancy between modeling results in a plane and volumetric formulation of the problem.
-
Date submitted2015-07-14
-
Date accepted2015-09-09
-
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.
-
Date submitted2010-07-28
-
Date accepted2010-09-30
-
Date published2011-03-21
Ingineering geological problems of high-rise construction with underground space development in Saint-Petersburg
- Authors:
- R. E. Dashko
- A. M. Zhukova
The history of high-rise construction is considered summarily. The main features of high-rise buildings and difficulties connected with theirs engineering and construction especially with underground space development and deep excavations in soft water saturated soils are characterized. Territorial construction guides «Residential and social high-rise buildings» prevail in Saint-Petersburg are analyzed in the context of recommendations for reliable basement choice. Brief description of Pre-Quanernary clays (Upper Vendian clays and Lower Cambrian clays) as basement for high-rise constructions are given. It is placed emphasis that the main feature of Pre-Quaternary clays is zone sequence of physical and mechanical properties and fissuring in depth. Physical and mechanical properties of Upper Vendian clays, Lower Cambrian clays and glacial clays are given. In addition, it is confirmed that glacial soils is not recommended to use as a basement for high-rise buildings.
-
Date submitted2010-07-30
-
Date accepted2010-09-10
-
Date published2011-03-21
Definition areas of possible migration gas fromthe reservoir by cross-hole seismic tomography method
- Authors:
- N. A. Poznyakova
Possibilities of cross-hole a seismoacoustic tomography method for studying tightness a tire-cover of a reservoir underground storehouse of gas (USG), created in water-bearing horizont. Research cross-hole spaces for definition zones possible migration and accumulation gas outside of a trap are considered. The system of supervision used at carrying out cross-hole seismoacoustic tomography is proved, the example of revealing zones migration and accumulation gas outside from reservoir is resulted. Prospects application the given method on USG in a monitoring mode are defined.
-
Date submitted2010-07-28
-
Date accepted2010-09-07
-
Date published2011-03-21
Modelling cavities nearwell areas for studyind of possibilities neitron well methods
- Authors:
- N. A. Poznyakova
Look into the possibility neutron method geophysical logging for determination zones of cavity nearwell areas gas reservoirs and determine the filler cavities. Relevant practicability using these methods on underground gas storage. Give an example these research on model and real conditions.
-
Date submitted2009-10-11
-
Date accepted2009-12-26
-
Date published2010-09-22
The analysis of factors, that cause processes of open hole wells’ destructions of Gatchina underground gas storage reservoir and prediction of sand effects
- Authors:
- D. V. Grishin
- A. V. Petukhov
- A. A. Petukhov
The peculiarities of elastic stresses in open hole wells’ of Gatchina gas storage reservoir are researched. It is revealed that in depression more than 1,5 MPa gas bearing rocks start to destroy. On the basis of studying of correlation relation between technological parameters of gas wells’ production and evacuation of sand the equations of plural regression are constructed. These equations are used to make prediction of sand evacuation at each producing gas well.
-
Date submitted2009-10-29
-
Date accepted2009-12-09
-
Date published2010-09-22
Problems and ways of exploration of the raw material resources base of the Zapoliarny branch of the Norilsk Nickel CO
Consideration is given to the geological, mining and operating conditions of the Norilsk industrial district. The analysis is made of the present-day state of mining production of the Zapoliarny branch of the Norilsk Nickel Co. The principal trends in the safe and efficient exploration of the raw material resources base have been stated within the Norilsk industrial district .