Collection of Research Papers of the National Mining University最新文献

{"title":"Development of elements of computer programming in component cross technologies of manufacturing mechanical equipment in engineering","authors":"V. Derbaba, V. Grigorenko, V. Ruban","doi":"10.33271/crpnmu/72.212","DOIUrl":"https://doi.org/10.33271/crpnmu/72.212","url":null,"abstract":"Purpose. Development of elements of programming on equipment with numerical software control in end-to-end technologies of manufacturing mechanical equipment in mechanical engineering. Method. It represents the analysis of scientific and technical information on \"digitalization\" in the development and issues of development of end-to-end technologies for the manufacture of mechanical equipment in mechanical engineering and the synthesis of tasks and development. The results. It is shown that the generally accepted technology for the production of metal parts and, accordingly, units of aggregates and machines in mechanical engineering consists of the main sequential technological operations: cutting of rolled blanks; forging or stamping of finished parts or forgings and stampings for subsequent mechanical processing by cutting; casting of finished parts or cast blanks for processing; processing of forgings or stampings and castings by cutting; if necessary, heat treatment of parts; if necessary, covering of parts; - assembly of nodes and machines. The given examples for each component technology showed a wide range of numerical software control products.A model of components in the \"digitalization\" of mechanical equipment manufacturing technologies and a model of the main components of the end-to-end technology of manufacturing metal engineering parts and \"digitalization\" elements have been developed.The relevance of developments on smoothing the joints of lines describing the shapes of product details is substantiated. It is proposed to use the possibilities of Bezier lines more widely. Scientific novelty. The elements of scientific novelty are in the created model of \"digitization\" of the components of end-to-end technologies for the manufacture of mechanical equipment in mechanical engineering and in the formulation of the application of Bezier lines for smoothing the joints of tool movement lines in the development of technological processes. Practical significance. The results of the article can be used in the development of end-to-end technologies for manufacturing mechanical equipment in mechanical engineering.","PeriodicalId":10466,"journal":{"name":"Collection of Research Papers of the National Mining University","volume":"5 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82128765","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":"Mathematical model of waste accumulation in Ukraine","authors":"T. Rusakova","doi":"10.33271/crpnmu/72.270","DOIUrl":"https://doi.org/10.33271/crpnmu/72.270","url":null,"abstract":"Purpose. Analysis and generalization of waste sources as factors that form the total volume of accumulated waste in Ukraine, which negatively affects the environment. Construction of a mathematical model of waste accumulation in Ukraine based on the results of the calculation of statistical indicators. Conducting research on the influence of selected factors on each other in order to avoid the phenomenon of non-collinearity or multicollinearity in the calculations. The methods. The application of multiple correlation-regression analysis methods for modeling, which allow, on the basis of the analysis of the studied statistical indicators, to single out the most statistically significant factor values, to assess the relationship between them and the relationship of these factor values with the resulting characteristic, which provides prerequisites for building a mathematical regression model. Findings. On the basis of descriptive statistics, an analysis of each of the studied factor values, such as generated, utilized, burned, removed waste, is presented, and the trends of their changes during 2010-2020 of years are established. The results of the correlation-regression analysis of statistical data are presented: the density of correlation relationships between the selected factor variables and the resulting variable; coefficient of linear determination; a measure of the quality of the regression equation. Those factor variables with weak correlation or multicollinearity were removed. A mathematical model based on regression-diffusion analysis was obtained and its adequacy was checked, the average relative error of the calculated data was 6 %, the maximum relative error was 10 %. The linear mathematical model was improved due to the introduction of non-linear variables, the average relative error of the calculated data was 3 %, the maximum relative error was 8 % Theoriginality. Dependencies and regularities have been established for the volumes of generated, utilized, incinerated and removed waste. A multifactorial mathematical model has been developed that establishes a relationship between different types of waste and the total amount of accumulated waste, which tends to increase, and this, in turn, increases the negative impact on the environment. Practical implementation. Mathematical apparatus for forecasting the total amount of accumulated waste due to the combined effect of generated, utilized, burned, removed waste and their combination, which is important when estimating the size of areas for accumulating waste and creating perspective plans for their disposal.","PeriodicalId":10466,"journal":{"name":"Collection of Research Papers of the National Mining University","volume":"20 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87378373","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 strength of cast and packaged concrete protective walls","authors":"O. Krukovskyi, S. Kurnosov, S. Makeiev, M. Stadnichuk","doi":"10.33271/crpnmu/72.053","DOIUrl":"https://doi.org/10.33271/crpnmu/72.053","url":null,"abstract":"Purpose. The substantiation of the compliance of the selected cement-mineral mixture with the mining and geological conditions of the working location when calculating the parameters of cast or packaged walls, considering the intensity of concrete hardening over time, the compliance of the set strength of concrete with the expected load. Method. To substantiate the compliance of the physical and mechanical properties of the pressure mixture on the means of protection of the production from the side of the fake roof of the coal seam, the values of the limit strength of concrete for uniaxial compression, obtained according to standard tests in laboratory conditions, are used. At the same time, concrete samples are subjected to uniaxial compression, the surfaces of which must be smooth and parallel, which does not correspond to the mine conditions for the construction and operation of cast and packaged protective walls. Quick-hardening liquid mixtures are used in the construction technologies of cast and packaged security walls. For some time, necessary for the hardening of concrete, they are not able to perceive the pressure from the rocks forged by longwall. Therefore, the criterion for evaluating the stability of cast or packaged walls is the correspondence of the rate of growth of the strength limit of the wall to uniaxial compression with the load from the forged roof of the coal seam at the moment of timeτ. Results.The importance of the impact on the strength limit of the concrete wall of each of the factors that create the risk of its destruction has been established. At the same time, the ranges of change of these factors are considered. The largest influence (up to 33%) is exerted by the coal seam capacity factor km. The scientific novelty of the work consists in the integration of the influence coefficients of the factors that create the risk of destruction of the concrete protective wall: its structure; relief of forged and crushed rocks pressing on the wall; chemical aggressiveness of mine water, which is used to dissolve the mixture; the temperature of the mine environment and the power of the coal seam to obtain a formula for calculating the growth of wall strength over time. The practical significance of the work lies in the improvement of the method of calculating the strength of concrete protective walls over time by considering the factors that form the mine conditions of their construction and operation.","PeriodicalId":10466,"journal":{"name":"Collection of Research Papers of the National Mining University","volume":"4 3 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88060334","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":"Features of development of the collection stone' current market","authors":"S. Shevchenko, D. Yastrebov, M. Sak, A. Moskalenko","doi":"10.33271/crpnmu/72.115","DOIUrl":"https://doi.org/10.33271/crpnmu/72.115","url":null,"abstract":"Purpose. On the basis of open sources of information, perform an analysis of the factors that led to an increase in the demand for collectible mineral specimens, identify the current popular trends in this market, show the potential of Ukraine in this field. The methods. The work uses general scientific research methods - empirical and theoretical (analysis, generalization, comparison, explanation). Findings. The main factors that led to the current increase in demand for collectible stones are highlighted, including the development of information technologies, the Internet, and social networks. Popular trends are identified and their connection with investment activities is shown, in particular such areas as museum and exhibition activities, cryptocurrencies, NFT technologies. A preliminary analysis of the availability and distribution of specimens of collection stones of Ukraine in modern museum collections of the world was performed, examples of the use of collection samples from the deposits of Ukraine as raw materials by the world's leading carvers are given, such a phenomenon as the activity of hunters, including at well-known domestic geological sites, is highlighted. The originality. The market for collectible mineral specimens is shown to be a powerful segment of the global gems market with annual sales of over $1 billion. Its capitalization continues to increase thanks to the artistic reinterpretation of these unique works of nature, the collections of which are now considered as alternative investments with the value of individual specimens at the level of 500 million dollars. The discovery of new mineral deposits, the emergence of a new class of collectors, as well as the development of cryptocurrencies justify the further development of collectible specimens’ market. Practical implementation. Examples of the commercialization of collectible specimens with the application of NFT technologies to them or to their digital images are given, usingof images of the specimens in modern art is shown on specific works of domestic and foreign artists and graphic products. Modern approaches to the formation of museum collections in the world's leading museums, the principles of philanthropy and aspects of attracting patrons, as well as the experience of attracting a wide range of visitors, which should also be applied to domestic state and university museum collections, are shown.","PeriodicalId":10466,"journal":{"name":"Collection of Research Papers of the National Mining University","volume":"82 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89650624","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 management of the properties of materials for the subsequent optimization of life cycles of products","authors":"S. Kovalevskyy, O. Kovalevska, D. Sydiuk","doi":"10.33271/crpnmu/71.194","DOIUrl":"https://doi.org/10.33271/crpnmu/71.194","url":null,"abstract":"Objective. The aim of the study is to establish the possibility of recognizing the characteristics of the internal state and confirm the influence of atomic or molecular bonds on the change of certain indicators of physical and mechanical properties of non-magnetic metallic (aluminum, copper) and non-metallic (polymeric) materials. Methods. The research is carried out on the basis of magnetic resonance using neodymium magnets and electric current modulated by white noise signal, as well as with the help of two neodymium magnets. Results. When using neodymium magnets and electric current modulated by a white noise signal in the range of 15-20000 Hz to create the effect of magnetic resonance for non-magnetic metallic materials, an increase in strength is observed until peak values are reached with a gradual decrease to the average value. The interaction of magnetic fields of neodymium magnet and electric current occurs in the body of samples at subcrystalline and subatomic levels. Therefore, this effect is explained by the fact that as a result of vibrations in the material there is a compaction of dislocations. At the moment of change of rest friction to sliding friction, the dislocation accumulation barrier is destroyed, after which the process is repeated again. When two neodymium magnets are used to create the effect of magnetic resonance for textolite and Plexiglas, i.e. for a group of non-metallic materials, the theory of a simultaneous decrease in entropy in the form of an increase in orderliness, namely the orderliness of domains and compaction of dislocations, with an increase in strength is confirmed. The influence of magnetic resonance treatment on changes occurring at the atomic and molecular level in polymeric materials is confirmed. Scientific novelty. The established dependences indicate a connection between the strengthening of the material and the improvement of the quality of its structure: ordering of domains and compaction of dislocations created by magnetic resonance. Practical significance. The obtained data give grounds for the development of a complex method of influence on a number of parameters of physical and mechanical properties using magnetic resonance based on neodymium magnets for influence and the possibility of predicting the life cycle.","PeriodicalId":10466,"journal":{"name":"Collection of Research Papers of the National Mining University","volume":"15 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85020993","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":"Identification of the thermal process in an induction motor","authors":"V. Kuznetsov, M. Tryputen, A. Nikolenko, D. Tsyplenkov, V. Kuvaiev, O. Savvin","doi":"10.33271/crpnmu/71.116","DOIUrl":"https://doi.org/10.33271/crpnmu/71.116","url":null,"abstract":"Purpose: synthesis of a mathematical model of an asynchronous motor, taking into account the impact of changes in the quality of electricity on the processes of heating and heat exchange for an economically justified choice of means of protection. Methodology: Theoretical substantiation of the expediency of using a one-mass thermal model of an asynchronous motor, for the conditions of operation of the latter in conditions of low-quality electricity, in order to determine losses in it. Results: Experimental studies of the operation of an asynchronous motor at nominal load were carried out. The obtained results of the measurements made it possible to determine the parameters of the single-mass thermal model, the heat transfer coefficient of the engine, and the coefficient of its heat capacity.A single-mass thermal model of an induction motor is a mathematical model used to describe the thermal processes occurring in an induction motor. This model is based on the assumption that all motor elements can be combined into one mass that heats up during engine operation. The model assumes that the thermal capacity of the motor is a constant, and the heat flow that is released during the operation of the motor is proportional to the square of the current passing through the motor windings. In addition, the model assumes the presence of thermal conductivity between the mass of the motor and the external environment, which affects the rate of heat dissipation. Scientific novelty: A methodology for determining losses in an asynchronous motor using a synthesized mathematical model is proposed, taking into account the influence of changes in the quality of electricity on the processes of heating and heat exchange in it. Practical significance: The obtained results indicate the adequacy of the proposed thermal model of an asynchronous motor operating in a network with low-quality electricity. Taking into account the fact that for many types of engines in the reference literature,there are no necessary data on the coefficients of heat transfer and heat capacity, and only the thermal time constants for certain types of engines are given, the value of the specified parameters of the model can be obtained on the basis of the methodology presented in the work.A single-mass thermal model can be useful for analyzing the thermal processes occurring in an induction motor and for improving the efficiency of the motor. In particular, it can help determine the optimal operating temperature of the motor, as well as calculate the necessary cooling system to ensure stable operation of the motor under conditions of variable load and temperature conditions.","PeriodicalId":10466,"journal":{"name":"Collection of Research Papers of the National Mining University","volume":"34 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84006886","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":"Investigation of the influence on the cross-wall difference of tubes of the double-feed and return cold pillar rolling process at the present conditions","authors":"O. Нolovchenko, V. Hrigorenko","doi":"10.33271/crpnmu/71.186","DOIUrl":"https://doi.org/10.33271/crpnmu/71.186","url":null,"abstract":"Purpose. An experimental study on modern cold rolling mills with double feed and turning on the effect of the cold rolling process on the change in the cross-wall variation in a batch of pipes and on the change in the value of the cross-wall variation at the ends of the pipes from the blank pipe to the finished pipe. The methodology is an industrial experiment on modern industrial equipment using modern devices. The study of changes in the cross-sectional variation in a batch of pipes was carried out during pipe rolling on the HPT -40-8 mill with feeding and turning the pipe in both extreme positions of the cage when rolling pipes measuring 25.4x2.11 mm. The study of the change in the cross-wall variation along the ends of the tubes from the blank tubes to the finished tube during rolling with double feed and rotation was carried out on the KPW-25 mill with feed and rotation in both extreme positions of the cage along the route of 33.7x3.2 → 16x1.5 mm steel pipes 08Х18Н10Т. The methods. The study of the change in transverse thickness from the billet to the pipe in a batch of pipes showed that the maximum value of the transverse thickness among the sample of pipes is 5.64%, the minimum is 0.85%. The average value is 3.51%, the root mean square deviation of the values of diversity is 1.174%. It is not always possible to obtain these accuracy values even at the state of the HPT, and when conducting the HPT process, where the feed is performed before the forward stroke, and the pipe is turned before the reverse stroke, it is practically impossible to obtain such indicators. The study of the change in the cross-wall difference along the ends of the pipes from the billet pipes to the finished pipe during pipe rolling on the KPW-25 mill with feed and rotation of the billet in both extreme positions of the cage showed that although the minimum values of the relative difference slightly increased, but in general the wall difference along the ends of the pipes significantly decreased. This makes it possible to reduce the cut at the ends of the pipes and, accordingly, the consumption coefficient of the metal. The originality. Additional experimental dependences were obtained on the change of the cross-wall variation from the billet pipe to the finished pipe in a batch of pipes and the change of the variation along the ends of the pipes during rolling with the execution of feed and rotation before the forward and reverse motion of the cage. Practical implementation. The conducted studies allow us to use the obtained experimental dependencies in the design of routes, deformation modes and determination of roll calibration in the manufacture of pipes with increased requirements for the accuracy of pipes in cold rolling mills, which have the ability to feed and turn the pipe before the forward and reverse movement of the cage.","PeriodicalId":10466,"journal":{"name":"Collection of Research Papers of the National Mining University","volume":"7 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87034695","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":"Establish of the optimum parameters of the Pinyazevytsky granite deposit mining system","authors":"B. Sobko, V. Kriachek","doi":"10.33271/crpnmu/71.017","DOIUrl":"https://doi.org/10.33271/crpnmu/71.017","url":null,"abstract":"Purpose. To conduct an analysis of the mining and geological features of the occurrence, the current state of development and the establishment of optimum parameters of the Pinyazevytsky granite deposit mining system elements. Methodology. Analytical, statistical, grapho-analytical, experimental research in the conditions of operating quarries, technical and economic analysis and forecasting were used during the research. Findings. The conducted research made it possible to analyze the mining and geological features of the occurrence and the current state of development, the analysis of the Pynyazevytskyi granite deposit mining system was carried out and their optimal parameters were substantiated.The average thickness of the mineral is 100.3 m. On the basis of the mining and geometric analysis of the quarry field, the average exploitation ratio of the overburden on the deposit was 0.07 m3/m3. Based on the calculations, the following parameters of the field development system elements are determined in the work: the minimum width of the working platform during the development of rock and dead-end dump truck turning is 27 m, and when the dump truck turns in a circle – 34 m; the width of the working area when working with rock and using the EKG-5A excavator is 51 m. The calculated maximum permissible height and slope angles of the ledges are: height of the ledge 15 m; the slope angle of the working ledge is 80°; the angle of stable slope is 75°. The width of the working area during the development of loose excavated rocks is calculated using the Volvo EC-240 excavator and is 39 m with ledges 5 m high. Originality. Conducted an analysis of the current state and features of the Pynyazevitskyi granite deposit development, substantiating the optimum parameters of the mining system elements for the open-pit mining of industrial mineral deposits. Practical value. The results of the research made it possible to establish the characteristic features of the mining enterprise, which significantly affect the mining of mineral deposit and the establishment of optimum parameters of the mining system elements for the mining of industrial raw materials for the production of aggregates.","PeriodicalId":10466,"journal":{"name":"Collection of Research Papers of the National Mining University","volume":"3 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90418092","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":"Petrography composion and ore-bearing of ultrabasits from the South-Bilozersky massif of the Middle-Dniprean mega-block of the Ukrainian shield","authors":"M. Ruzina, O. Tereshkova, Y. Dementieva, I. Zhyltsova, M. Maľová","doi":"10.33271/crpnmu/71.160","DOIUrl":"https://doi.org/10.33271/crpnmu/71.160","url":null,"abstract":"Purpose. To determine the matter composition, formational types and degree of hydrothermal-metasomatic alterations of the ultramafic rocks from the South-Bilozersky massif and substantiate the prospects for the ore potential of geological formations. Methods. To accomplish the tasks set, traditional methods of studying the matter composition of rocks and ores, such as petrographic, mineragraphic, were used, the results of chemical, X-ray diffraction, semi-quantitative spectral and thermal analyzes were interpreted. To determine the prospects of ore-bearing, ore-formation analysis and a comparative geological method were used.The use of a complex of modern methods and the interpretation of the research results made it possible to substantiate the ore-formational types of associated raw materials. Findings. The features of the matter composition, internal structure and ore content of the s South-Bilozersky serpentinite massif are characterized and the genetic relationship with the known differentiated basic-hyperbasite massifs of the Bushveld, Stillwater, Duluth, Big Zimbabwe dyke types is substantiated. The presence of cumulative dunites and peridotites within the South-Bilozersky massif suggests their intrusive origin from a deeper source with chamber differentiation. The prospects for the discovery within the South-Bilozersky massif of a medium-sized deposit of talc-magnesite, easily accessible for development in the conditions of the infrastructure of the iron ore plant, are substantiated. The affiliation of talc-magnesite ore occurrences to the hydrothermal-metasomatic formation of listvenites, which were formed during the active introduction of silica and carbon dioxide into the high-magnesian environment of deformed serpentinites, is substantiated. The originality. For the first time, the dislocation-metamorphic genesis of hydrothermal ore-bearing formations within the South-Bilozersky ultramafic massif was substantiated and the influence of the degree of hydrothermal alterations on the quality and degree of preservation of ore formations was shown. Practical implementation. The prospects for ore occurrences of minerals accompanying iron deposits in the Belozerskaya greenstone structure are substantiated, which will make it possible to implement an integrated approach to the development of the bowels of the traditionally iron ore region.","PeriodicalId":10466,"journal":{"name":"Collection of Research Papers of the National Mining University","volume":"96 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89155168","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":"Justification of the application of low-viscus polyurethane in conditions of poorly water-saturated soils","authors":"M. Musykhin, G. Tuganov","doi":"10.33271/crpnmu/71.071","DOIUrl":"https://doi.org/10.33271/crpnmu/71.071","url":null,"abstract":"Purpose. Analytical justification of the method of strengthening the stability of the water-saturated alluvial soil massif around the subway tunnel by the method of jet cementation using low-viscosity polyurethane. Consider the advantages of this material and present the strength characteristics. The methods. Analytical justification of the method of strengthening the stability of the water-saturated alluvial soil massif around the subway tunnel by the method of jet cementation using low-viscosity polyurethane. Consider the advantages of this material and present the strength characteristics. Findings. The use of a mixture of concrete and low-viscosity polyurethane during jet cementing allows to increase the strength characteristics of piles, thanks to the advantages of polyurethane. The material has a high density, ozone resistance, stability at high and low temperatures, the possibility of use under significant mechanical loads, with a high density, it does not have a large mass, it is elastic. When filling wells with a mixture of cement and polyurethane solution in interaction with water-saturated soil, the physical and mechanical characteristics of the soil and the load on the structure of the metro tunnel change. Based on the analysis of the data on the consolidation of the soil massif, it can be highlighted that to increase the stability of the water-saturated soil massif, it is advisable to use the jet cementation method with the addition of low-viscosity polyurethane. The originality. The use of low-viscosity polyurethane as a cementing material by jet cementation is highly effective in cementing weak water-saturated soils. The use of polyurethane will make it possible to shorten the period of work, reduce the amount of material, and increase operational characteristics. Practical implementation. The silicification method is common and convenient for strengthening underground soil in the case of dense urban development, but the use of piles as a result of mixing soil with polyurethane will not only reduce the duration of work, but also reduce the cost and increase the speed of pile hardening, increase the range of coverage of the water-saturated massif near the tunnel, will reduce the possibility of the formation of an anti-filtration cushion, which is safer for urban development","PeriodicalId":10466,"journal":{"name":"Collection of Research Papers of the National Mining University","volume":"22 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80767336","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}