Geo-Technical Mechanics最新文献

{"title":"Uranium sorption from radioactive waste of uranium ore processing at Pridneprovsk Chemical Plant","authors":"","doi":"10.15407/geotm2021.157.212","DOIUrl":"https://doi.org/10.15407/geotm2021.157.212","url":null,"abstract":"Abstract. The research results were generalized regarding the possibility of uranium sorption from radioactive waste accumulated at Production Association “Pridneprovsky Chemical Plant” (PA PCP). The conceptual possibility was illustrated for sorption leaching of uranium from pulps produced by acidic leaching of radioactive waste dumped at Zapadnoye (Western) tailing impoundment using AMP anionite contained benzyl pyridinium functional groups (manufactured by Smoly State Enterprise). Uranium recovery was 70 % to 80 % during waste acidic leaching with the mixture of 15 % sulphuric and 1.5 % nitric acids. Application of sorption leaching allowed the recovery increase up to 15 %. Uranium recovery was assessed from upper ground and underground water of Centralny Yar tailing site using AM-p-2 strong base macroporous anionite (produced by Smoly SP) based on styrene-divinyl benzene copolymer with 2-hydroxyethyl-dimethylammonium functional groups. This tailing impoundment features acidic reaction of radioactive water since the pulp was almost not neutralized after ore processing. It poses an environmental hazard due to active uranium leaching from the tailing impoundment body and its ability to migrate into groundwater. It was found that the distribution factor may attain ~2 000 for uranium concentration 7 mg/l in interstitial water and 4 mg/l in underground water. Assessment results were given regarding uranium recovery from radioactively contaminated water accumulated in the basement of building No. 103 using phosphate cationite based on modified plant material. The building is extremely contaminated and of top-priority for treatment and further dismantling. Sorbent capacity by uranium achieved in static mode was ~20 mg/g with distribution factor ~4 800. The results obtained may be proposed as the reasoning for the method and technology intended to decontaminate polluted water before it would be pumped from underground rooms of building No. 103. The research performed has shown that application of sorption materials is the most expedient and promising method for selective uranium recovery when solving the problems of tailing site remediation and handling radioactive waste of the former Pridneprovsky Chemical Plant.","PeriodicalId":222378,"journal":{"name":"Geo-Technical Mechanics","volume":"168 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132105586","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Research of the insulating properties of respirator half mask","authors":"S. Cheberyachko, Y. Cheberyachko, D. Radchuk, O. Stolbchenko, D. Klimov","doi":"10.15407/geotm2019.149.223","DOIUrl":"https://doi.org/10.15407/geotm2019.149.223","url":null,"abstract":"","PeriodicalId":222378,"journal":{"name":"Geo-Technical Mechanics","volume":"130 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128708560","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"To estimation of temperature fluctuations in diamond grains when drilling with diamond bits","authors":"","doi":"10.15407/geotm2021.157.172","DOIUrl":"https://doi.org/10.15407/geotm2021.157.172","url":null,"abstract":"Abstract. If we consider the interacting pair: the matrix of a diamond crown, reinforced with protruding diamonds and rock, as a kind of system, then in the process of friction of the matrix against the bottom hole, external mechanical energy is converted into the energy of the heat and matter flows. The main concentration of the flows occurs in places where diamonds protrude above the matrix and take on an additional load. The rubbing system tries to smoothing itself by concentrating pressure and temperature on the diamonds. Diamonds, due to their higher hardness than the destructible medium, are pressed into the rock and destroy it. Since the process of cutting rocks is intermittent, the concentration of energy on diamonds occurs periodically, in the form of “flashes”. Each such “flash” is accompanied by a short-term increase in temperature in the contact zone (temperature fluctuation) and the spalling of a microparticle of the rock. In this work, from the standpoint of thermoelastic instability, the issue of temperature microflashes in single diamonds during the interaction of rough surfaces of the matrix of the diamond crown and the bottom of the borehole is considered, in order to take this factor into account in the mechanism of wear of the diamond of the drill bit. The value of temperature fluctuations on the surface of cutting diamonds was estimated and the size of the flash zone was determined. It is shown that temperature flashes of 400 (С < T* < 3650 (С are observed when drilling granite with a diamond crown on the diamond surface in an area of 5.8(10‑5 m, therefore, the presence of such “microflashes” on the diamond surface in a very small area in the process of interaction with the rock can lead to graphitization of the diamond in this place and separation from the surface of the grain. Such a mechanism should play a certain role in the wear and destruction of diamond surface areas during drilling. The magnitude of temperature fluctuations depends on the physical and mechanical properties of the contacting pair: diamond – rock, operating parameters of the tool and the nature of the placement of diamonds in the crown matrix. In this regard, the study of the assessment of temperature fluctuations in diamond grains when drilling with diamond bits may be of practical interest. Keywords: rock, thermal stresses, intensive cooling, macro- and microcrack system.","PeriodicalId":222378,"journal":{"name":"Geo-Technical Mechanics","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125347788","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of the advanced degassing in the affected zones of deformation processes","authors":"V. Zberovskyi, M. Chetveryk, V. Vlasenko, K. Zmiievska, K. Dudlia","doi":"10.15407/geotm2022.161.042","DOIUrl":"https://doi.org/10.15407/geotm2022.161.042","url":null,"abstract":"","PeriodicalId":222378,"journal":{"name":"Geo-Technical Mechanics","volume":"150 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114530102","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Control of technological processes and reduction of gas dynamic hazard on the basis of using the acoustic afteraction","authors":"","doi":"10.15407/geotm2021.157.003","DOIUrl":"https://doi.org/10.15407/geotm2021.157.003","url":null,"abstract":"The objective of the work was to develop new methods for controlling technological processes during driving development headings and mining coal in stope faces. Accidents happened while performing of underground mining operations are often caused by the so-called “human factor”: miners do not always accurately follow the safety regulations, namely, the roadways are not supported in due time, the gas-drainage boreholes are drilled to the wrong depth, duration of the fluid injection at hydraulic loosening is cut, etc. In real conditions, it is difficult to control all the technological processes occurred underground. Therefore, the purpose of the study was to develop recommendations for controlling technological processes in the mines in order to reduce the risks of gas-dynamic phenomenon occurrence. In this work, the authors present further development of the most rational known approach to the control of technological processes consisted in assessing of gas-dynamic hazard by the method of seismoacoustic aftereffect. The nature of changes in acoustic activity depending on the type of winning operations was analyzed. The clearer differentiated assessment of the stress-strain state of the coal seam face area was obtained. The study of the acoustic aftereffect during the mining of a coal seam by different technological methods made it possible to assess the technology of winning operations from the point of view of ensuring safe working conditions. The block diagram was built, on the basis of which an algorithm of performing operational control of technological processes in development headings and stope faces was developed, including operations in prone-to-outburst seams. The basic requirements for the correction of existing software for the classification and recognition of technological processes by their acoustic aftereffect (trace) in the records of the predicting systems carried out during mining operations in the mine were formulated. These recommendations for the control of technological processes were proposed the Pokrovskoe Mine for implementation. The proposed recommendations improve accuracy of the forecasting of gas-dynamic hazards during mining operations, make it possible to control technological processes as well as simplify the investigation procedure for establish the causes of a critical situation in the case of an accident. The implementation of the recommendations will also make it possible to assess a gas-dynamic hazard during stoppages for repair and other auxiliary work, to predict geological disturbances ahead of the moving face, to determine the size of the unloading zone of the bottom area of the coal seam, and to assess the effectiveness of measures to prevent gas-dynamic phenomena. Keywords: acoustic aftereffect, technological processes, gas-dynamic phenomenon, safety of mining operations.","PeriodicalId":222378,"journal":{"name":"Geo-Technical Mechanics","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114871541","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Rubber vibroinsulators of cylindrical form, applicability limits and the expansion of their use area","authors":"M. Lysytsia, T. O. Tverdohklib, O. Zabolotna, N. Lysytsia, A. Novikova","doi":"10.15407/geotm2019.144.117","DOIUrl":"https://doi.org/10.15407/geotm2019.144.117","url":null,"abstract":"","PeriodicalId":222378,"journal":{"name":"Geo-Technical Mechanics","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117132469","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental research of efficiency of the crusher with wave profile of rolls during destruction of lamellar pieces","authors":"","doi":"10.15407/geotm2022.160.071","DOIUrl":"https://doi.org/10.15407/geotm2022.160.071","url":null,"abstract":"","PeriodicalId":222378,"journal":{"name":"Geo-Technical Mechanics","volume":"230 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115016509","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Stress distribution in a rubber-metal block under compression by static load","authors":"","doi":"10.15407/geotm2021.157.080","DOIUrl":"https://doi.org/10.15407/geotm2021.157.080","url":null,"abstract":"Abstract. The problem of determining the stress-strain state of a prismatic rubber-metal block when it is compressed by a static load is considered. A mathematical model is proposed, which assumes that when a block is compressed by a vertical load, its horizontal sections remain horizontal, the metal components of the block are rigid, non-deformable, points located on a vertical line during loading remain on a parabola, and rubber is considered incompressible. Accepted assumptions provided an opportunity to obtain expressions for movements along the axes of symmetry, which provide the expected parabolicity during compression of the rubber-metal block and satisfy the condition of incompressibility. The formulas for normal and tangential stresses arising during block compression are derived, which satisfy the differential equation of equilibrium of the elementary volume, Hooke’s law, and take into account the boundary conditions on the sides of the rubber body. Given the geometric parameters of the block and the mechanical characteristics of the rubber, it was possible to calculate its drawdown depending on the degree of static load, as well as to analyze the distribution of normal and tangential stresses that occur in the block. The developed mathematical model of the compression process allowed, as an example, to analyze the stress-strain state of a rubber-metal block of the BRM‑102 type, for the manufacture of which rubber of the brand 51‑1562 was used. As a result of solving the problem, distribution diagrams of normal, tangent, and total stresses arising in dangerous sections (on the upper or lower sides of the rubber body) under loading are constructed. It was found that the maximum normal stresses and maximum total arise on the vertical axis of symmetry of the block; maximum tangential stresses are realized at corner points. The ability to receive this type of illustration allows you to visually determine which is more rational to use: one block with a horizontal section of 200(100 mm or two blocks with a size of 100(100 mm. The proposed mathematical model allows us to study the stress-strain state of a rubber-metal block under compression, and can also be used in the design of a block with predetermined characteristics. Keywords: rubber-metal block, stress-strain state, displacements, stresses, relative deformation, mathematical model.","PeriodicalId":222378,"journal":{"name":"Geo-Technical Mechanics","volume":"97 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123701359","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Calculation of the changing cofficient of the folmerov diffusion of methane desorped from coal in the face area of the coal layer at great depths","authors":"S. Minieiev, A. Prusova, O. Yanzhula, Roman Sachko, O. Minieiev","doi":"10.15407/geotm2021.156.036","DOIUrl":"https://doi.org/10.15407/geotm2021.156.036","url":null,"abstract":"An algorithm for calculating the Volmer diffusion coefficient of methane adsorbed in coal in the bottomhole zone of the formation to the maximum reference pressure is developed with taking into account the change in the Folmer porosity and the size of the space of this zone. The algorithm is based on the using of the exponential law of compression, which describes the structural changes in the reference pressure of the coal seam. This allowed us to determine the diameter of the Folmer pores in the study area depending on its stress state. Based on these data and the calculation of the exponential nature of the change in porosity, the regularity of the Folmer diffusion in the bottomhole region at its fixed length and initial porosity of coal is established. By using a method of step-by-step approximating the solution of this problem for different parameters, the research results are generalized to the existing ranges of change in the Folmer porosity of coal and the size of the bottomhole region of reference pressure in mining conditions at great depths. The functional approximation dependence is established, which allows to perform calculations of the Volmer diffusion coefficient of methane desorbed from the coal layer, with simultaneous change of two parameters - initial porosity of coal and distance between the bottom to the maximum reference pressure zone. Calculations showed that when reference pressure approached its maximum at a distance of up to 10 m from the face the coefficient of Folmer diffusion of methane in coal decreased slightly. In this case, there is a strong dependence of the Volmer diffusion coefficient on the diameter of the Folmer pores in the virgin coal layer. For example, when this diameter increases twofold - from 8 А to 16 А at the distance of 20 m from the face to a maximum reference pressure, the coefficient of Folmer diffusion increases by 1.5 times. That is, Folmer's diffusion is the most intensive in the disturbed zones of the coal layer. This can be the area of maximum reference pressure, if there is a zone of disintegration, or in that part of the face zone, which is characterized by the developed system of fractures. Key words: adsorbed methane, coal layer, face zone, Folmer pores, Folmer diffusion coefficient.","PeriodicalId":222378,"journal":{"name":"Geo-Technical Mechanics","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129771574","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Research and development of structures for stretching ribs and profile conductors in pile","authors":"A. A. Rubel, SP «OK«Ukruglerustrukturizatsiya»","doi":"10.15407/geotm2019.149.016","DOIUrl":"https://doi.org/10.15407/geotm2019.149.016","url":null,"abstract":"","PeriodicalId":222378,"journal":{"name":"Geo-Technical Mechanics","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130195899","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}