Browsing by Author "Radkevych, Anatolii V."

Now showing 1 - 28 of 28

Abstracts of the international scientific and practical conference “IInnovations in construction and smart building technologies for comfortable, energy efficient and sustainable lifestyle”. (20–21 February 2024, Dnipro, Ukraine ).
(Prydniprovska State Academy of Civil Enginering and Architecture, 2024) Savytskyi, Mykola; Sukhyi, Kostiantyn; Danishevskyy, Vladislav; Radkevych, Anatolii V.; Nazarenko, Ivan; Proidak, Yurii S.
ENG: Conference abstracts provide the findings of research and practical application in the field of innovations in construction and smart building technologies for comfortable, energy efficient and sustainable lifestyle by scholars, representatives of education, business, government to be used for reconstruction of Ukraine (in terms of the project ‘A novel decentralized edge-enabled prescriptive and proactive framework for increased energy efficiency and well-being in residential buildings’, sponsored by HORIZON 2020 EU programme (grant no. 958284 − PRECEPT).
Analysis of Modes and Frequencies of Natural Vibrations and Dynamic Stresses of Bridge Abutment Foundation and Soil Base
(Український державний університет науки і технологій, Дніпро, 2025) Radkevych, Anatolii V.; Dubinchyk, Olha I.; Hu, Zuolin; Kozak, Bohdan Yu.
ENG: Purpose. The purpose of the research work is to determine, during the modal analysis, the modes and frequencies of natural vibrations of the railway bridge abutment together with the pile cap and pile foundation. A separate task of the research is to clarify the dynamic influence of the abutment structure on the possibility of vibrational displacements of the soil base. Methodology. To calculate the pile foundation of the abutment, which interacts with the surrounding massif, it was decided to use the finite element method (FEM) based on Structure CAD for Windows, version 7.31 R.4 (SCAD). To reproduce the features of the pile foundation of the abutment, a flat (quasi-spatial) model was used in the research. All dimensions of the pile cap and piles are adopted according to the design documentation for the construction of an actual overpass. Findings. An analysis of the stress-strain state results of the overpass abutment foundations, taking into account the train load, was performed, which made it possible to obtain a conclusion about the high bearing capacity of all parts of the “pile – pile cap” system for all considered types of load combinations with a safety margin of 8 and 7 times, respectively, which indicates normal operation in the future provided an unchanged state of engineering and geological conditions and loads. The pile material, class C30/35 concrete, fully withstands all types of loads represented by load combinations, taking into account the dynamic coefficient. The modal analysis of the overpass abutment foundations shows that the obtained frequencies and modes for the foundation are equal to 2.5 Hz (fundamental tone) … 6.6 Hz, and from comparing these frequencies with the liquefaction frequencies of wet sands (30 … 50 Hz) it is clear that the support's own vibrations cannot cause vibration-induced liquefaction. Originality. The originality of the conducted research lies in obtaining the parameters of dynamic displacements and natural vibration frequencies during the modal analysis of a railway bridge abutment Practical value. The practical value lies in substantiating the strength of the abutment structure under varying load combinations, as well as in determining that the dynamic impact of the rolling stock does not affect the vibrational displacements of the foundation soils.
Application Prospects of Threaded Joint of Armature
(Дніпропетровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпропетровськ, 2014) Radkevych, Anatolii V.; Netesa, Andrii M.
ENG: Purpose. One of the main technological operations of buildings construction on the basis of monolithic frame systems is the production of mesh reinforcement. The current interest is the new ways specification of advanced bonding armature techniques without reliability weakness and design of the building in whole, as well as the finding of use prospects of screw-threaded joint of armature as the most technological and economic method of re-bars joints. Methodology. Advantages and disadvantages analysis of existing rebar compound technologies was implemented by couplings of different types and constructions. The most promising vertical constructions for the vertical bars joints in frameworks were determined. Findings. Researches of existing technologies of rebar joints by the couplings of different construction were carried out. The installation method of mesh reinforcement of vertical structural elements with the use of the special catching devices was developed. It allows considerably accelerating installation of mesh reinforcement. Originality. Regularity of labor intensiveness change of mesh reinforcement installation of columns at armature joint in vertical position by threaded couplings with the help of catching devices using special construction was determined. This allows substantially reducing the labor expenditures during installation of these elements. Dependency of labor intensiveness and cost of lap welding armature joints, by tub-seam welding and by thread coupling depending on its diameter was designated. Regularity of labor intensiveness changes of installation at armature joints by different methods taking into account preparatory works was defined. Practical value. The analysis of mechanical armature joints techniques was conducted. It will allow selecting methods of armature joints to increase the speed of construction works more economical and effective.
Aspects Definition of Reliability Evaluation Facade Systems From the View Point of Eurocode
(Дніпропетровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпропетровськ, 2015) Radkevych, Anatolii V.; Netesa, Kostiantyn M.
ENG: Purpose. This paper is devoted to the definition of the most rational technique of reliability evaluation of facade systems of multistoried residential buildings with using the experience of buildings construction and operation abroad. The subject is also focused on defining the parameters of materials and facade systems, the improvement of which can increase the reliability and durability of facade systems of multistoried residential buildings, as well as cut the cost of their operation. Methodology. A comparative analysis of the operating experience of various types of facade systems in Ukraine and abroad based on the data of different authors was conducted. The analysis of the impact of external factors on facade systems with the subsequent comparison of methods for assessing the reliability of facades according to the criteria stated in the Eurocode was carried out as well as the selection of parameters that determine the reliability and durability of facade systems. Findings. Authors have performed researches of valuation methods of organizational and technological reliability and durability of modern facade systems. It was identified the cause of the failure of facade systems. It is offered the ways of materials improvement of facade systems, and constructional and organization-technological decisions on the structure of facade systems. Methods of increase of reliability and durability of front systems were defined. Originality. The most rational technique of reliability evaluation of facade systems considering requirements of Eurocode in questions structural design was defined. Practical value. Improvement of evaluating methods for organizational-technological reliability of facade systems of multistoried residential buildings will predict more accurately the lifetime of enclosures. Using the methods described in the Eurocodes, to determine the reliability and durability of the facade systems will provide the general criteria for the building structures design in Ukraine and Europe, as well as facilitate the exchange of experience in the construction and operation of buildings between the countries of Europe. An analysis of the causes of failures of facades enables to determine the directions of improving the properties of the materials used for the manufacture of facade elements structures as well as engineering and technological solutions of applied facade systems.
Assessment of the Impact of Operating Conditions on the Reliability of Bar-Type Steel Structures
(Український державний університет науки і технологій, Дніпро, 2025) Ivanova, Hanna; Radkevych, Anatolii V.; Olishevska, Sofiia; Tianwei, Ma
ENG: Purpose. The study aims to develop a comprehensive approach to calculating the residual service life of spatial multi-element steel bar structures, taking into account both predictable and random factors that affect the structures or their individual elements throughout their service life. Methodology. The key causes of corrosion damage are examined, and models of corrosion wear are analyzed, including those that consider the effects of mechanical stresses and aggressive environments. The use of different types of survivability indicators – both deterministic and stochastic – allows for a more accurate assessment of structural reliability under real operating conditions. It is noted that current construction standards insufficiently account for the time-dependent development of defects, which complicates the assessment of the residual service life of structures. The need for a comprehensive approach to forecasting the reliability and durability of steel structures in actual service conditions is emphasized. Findings. It is demonstrated that traditional calculation methods do not adequately assess the durability and survivability of structures with evolving defects. An approach to evaluating the survivability of steel structures is proposed, based on the use of both deterministic and stochastic indicators. This allows for consideration of both systematic and random changes in the behavior of the structural system. The advantage of mathematical modeling over physical modeling is substantiated, particularly in its ability to account for multiple scenarios of corrosion development and the complex interaction of corrosion with mechanical influences. Parameters characterizing the condition of a structure under corrosion wear have been identified. Originality. A comprehensive approach to assessing the reliability and survivability of bar-type steel structures under corrosion wear has been developed, based on a combination of deterministic and stochastic indicators. Mathematical models of corrosion damage are considered, taking into account the influence of both stress–strain state and aggressive environments. Practical value. The obtained results can be used in the design, diagnostics, and forecasting of the technical condition of bar-type steel structures operating in aggressive environments and exposed to various types of loads.
Choice of STFT and WT Parameters for Monitoring of EMI in Track Circuits
(Institute of Electrical and Electronics Engineers, 2023) Havryliuk, Volodymyr I.; Nibaruta, Regis; Radkevych, Anatolii V.
ENG: The article considers the problem of the correct choice of the parameters of the short-time Fourier transform and the continuous wavelet transform to ensure monitoring of electromagnetic interference in rails in order to ensure the electromagnetic compatibility of traction current with track circuits. The problem of correct choice of parameters for the time-frequency analysis of currents in track circuits lies in the strict requirements of the standards for the accuracy of measuring the magnitude, frequency, and duration of disturbances, as well as in the specifics of the measured current parameters and in restrictions inherent in the short-time Fourier transform and continuous wavelet transforms on the accuracy of measuring harmonic parameters. The specificity of currents in rails is associated with a large dynamic range of harmonics, a wide frequency range and the proximity of harmonics in the spectrum to each other, which makes it difficult to distinguish weak harmonics against the background of more powerful ones, as well as in the non-periodic and random nature of current. The paper considers the technology of the correct choice of parameters of the short-time Fourier transform and the continuous wavelet transforms. The results of the work were approved during testing of new types of trains.
Comparative Analysis of the Parameters of the Strength of the Subgrade at the Transition to the Higher Axial Loading up to 25 t
(IOP Publishing, Kharkiv, 2019) Radkevych, Anatolii V.; Petrenko, Volodymyr D.; Tiutkin, Oleksii L.; Andrieiev, Volodymyr S.; Mukhina, Nataliya
ENG: Abstract. A review of the scientific and technical literature on the re-alignment of the route during the transition to high axial load from the accepted today (23.5 t / axis) to the perspective (25 t / axis) shows that in the stage of preliminary researches imitation modeling of the earth web by the finite element method (ITU) as the most convenient, accurate and illustrative of the known numerical methods. In order to provide recommendations on the strength of the subgrade when moving to a higher axial load up to 25 t / axis, an analysis was conducted, the essence of which was to compare the stress-strain state of the subgrade at two loads per axis: 23.5 t / axis (existing ) and 25 (perspective). All the geometric and deformation characteristics of the formation are taken from data on a two-track section with a height of embankment of 3. The deformation characteristics are chosen so that the working material of the formation is in accordance with the average indices of deformation capacity of the railways used. The ITU train load calculus makes it possible to obtain all the factors of VAT in it, which is the main purpose of the study of the strength of the earth cloth, and allows to forecast their development in the future.
The Comparative Analysis of the Stress-Strain State of the Support of the Escalator Tunnel Constructed in Weak Soils by the NATM
(IOP Publishing Ltd, 2022) Radkevych, Anatolii V.; Tiutkin, Oleksii L.; Kuprii, Volodymyr; Bielikova, Sofiia
ENG: The construction of underground objects of the subway is always associated with building of structures connecting the surface. For subways, such structures are escalator tunnels. During the construction of the Dnipro Metro, these underground structures are built using a new technology that forms a multilayered support. This technology is the New Austrian tunneling method. A special feature of its application under the conditions of the Dnipro city is the existence of weak rocks in the upper part of the escalator tunnel. To ensure their stability, various special operational techniques are used that impact the rock massif. The basic techniques include artificial freezing, which was the dominant strengthening technology, and chemical strengthening (cementation), which is more consistent with the New Austrian tunneling method. To elucidate the effectiveness of the two strengthening techniques, a finiteelement model of the Dnipro Metro escalator tunnel has been built. The numerical calculation of two variants for the strengthening of weak soils yielded results for a comparative analysis of the stress-strain state. The result of the comparative analysis is the conclusion of greater cementation efficiency when strengthening weak soils of the massif in which the escalator tunnel is constructed using New Austrian tunneling method.
Determination and Ranging of Organizational and Technological Factors that Define the Rational Decisions of Re-Bars Connection
(Dnipropetrovsk National University of Railway Transport named after Academician V. Lazaryan, Dnipro, 2017) Radkevych, Anatolii V.; Netesa, Andrii M.
ENG: Purpose. The paper proposes: 1) determination and formulation of factors that influence the choice of rational method for joining re-bars of vertical support members of reinforced concrete frame; 2) determination of factor parameters; 3) ranging of factors by the expert evaluation (Delphi) method. Methodology. In order to achieve research objectives, it is necessary to carry out analysis of existent rebar connection methods, determination of factors and parameter variation limits for each of the methods. Performing factor ranking by the expert evaluation method. Findings. The results of the questioning materials of 14 experts in the area of monolithic construction allowed setting the following: when choosing the rational re-bars connections, the most significant values are the factors that define the time parameters: possibility of carcassing, time of joining the re-bars, length of rebar cage, prior operation run time, operation time of main lifting equipment. Herewith the factors that define the rebar cage parameters have a direct relation to the work performance time, as they determine the amount of bar connections in the course of building erection over wide range. Economic factors – rebar connection cost and quality control cost – have the less value. It is obvious that in the conditions of considerable construction expenses it is advantageous for an investor to increase the rebar joining cost for the work growth rate. Structural and technological factors have the least value: origin of eccentric load transmission between re-bars, possibility of use of the thermally workhardened re-bars of А500 and higher grades, work category for implementation of works, necessity to use the scaffold and appurtenances for re-enforcement of constructions. The reason is analogical: a contractor is ready to go to complication of technology with the purpose of reduction of the facility erection terms. As the calculated Pearson’s matching criterion χ 2 = 47.24 is higher than the tabular one (22.36203), then the obtained concordance coefficient W=0.26 is not casual value, and that is why the obtained results make sense and can be used in further researches. Originality. The author obtained factors that influence the choice of the rational method for re-bars connection the most. Practical value. Ranging of factors will allow objective approaching to the problem of choice of re-bars connection method, optimizing the labour and material costs, and also reducing the construction time.
Digital technologies as modern infrastructure for information support of education and scientific communication: the experience of USUST
(Український державний університет науки і технологій, Дніпро, 2025) Radkevych, Anatolii V.; Kolesnykova, Tetiana O.; Soroka, Maksym L.; Rybalka, Roman V.
ENG: This paper examines the experience of the Ukrainian State University of Science and Technologies in employing digital technologies as a contemporary infrastructure for supporting educational and scholarly communication. It presents a concise overview of the Erasmus+ project “Open science supporting vulnerable communities: empowering university libraries in crisis response” (CAELUM), in which the authors are participants and which materials underpin this study. Within the framework of the CAELUM project, the authors investigated the experiences and expectations of users interacting with the scientific libraries of Ukrainian universities during crises. Anonymised data were collected from 72 respondents aged 18 and above, representing diverse roles within the academic community, through online interviews and questionnaires. Responses to five closed-ended questions were analysed using cluster analysis, resulting in the identification of four distinct respondent clusters. Subsequently, a semantic analysis was conducted on responses to four open-ended questions. The findings enabled the identification of four target user groups of university library services in the context of crisis response. This provides a basis for university libraries to organise their activities more effectively by accounting for the needs and interests of these groups.
Efficiency Estimation of the Shaped Hot Rolled Steel Product Mix of India and Ukraine
(Національний університет будівництва і архітектури, Київ, 2019) Gaidaichuk, Victor V; Bannikov, Dmytro O.; Radkevych, Anatolii V.; Muntian, Antonina O.
ENG: The publication presents main results of the performed quantitative and qualitative analysis of modern shaped rolled metal products of India, which is used for structural steel members. Its efficiency was compared to the current domestic product range of Ukraine on the example of angle bars, channel sections and flanged beams. Special attention is paid to the system of designations and marking of product mix items. The publication presents the main results of the quantitative and qualitative analysis of the modern hot rolled steel assortment of India, which is used for steel building structures. The shaped hot rolled steel products are considered, represented in the standards of both countries by four types of profiles – equal leg angles, unequal leg angles, channel and beams. Special attention is paid to the system of designations and labeling of products of the assortment. In general, it should be noted that the overall organization and principle of construction of the analyzed assortments of India and Ukraine are quite similar. The main fundamental difference is the availability in the standard of India of a wider range of profile varieties within one step, which makes it possible to more efficiently choose the required section in the design. However, the step itself is widely than in domestic standards, which negates such dignity. Angels profiles in the Indian assortment have a wider range of thicknesses and are represented by a large number of sizes, especially for unequal leg angles, which is connected with a significant distribution of such profiles in the supporting elements of steel structures. Channel profiles in general have approximately the same degree of efficiency and the number of standard sizes in the assortments of both countries. In the standard of India, profiles with flange slopped shelves are displayed in more way and, in the domestic standard, with parallel shelves. Beam profiles have the largest number of sizes in both assortments, but unlike the domestic standard in India's standard, they are presented only in cross-sections with flange slopped shelves. In this case, the profiles aimed at bending, according to the domestic assortment have specific characteristics averaged on 15 – 40 % higher with a less on 30 – 40 % by weight. For profiles of heavy series, oriented also on the perception of longitudinal forces, sections in the Indian assortment have higher specific characteristics and less weight on average by 20 – 30 %.
Features of Modern Design of Steel Crane Beams for Industrial Buildings
(Український державний університет науки і технологій, Дніпро, 2025) Radkevych, Anatolii V.; Bannikov, Dmytro O.; Chen, Shangping P.; Fu, Xiaofeng F.
ENG: Purpose. The main purpose of the publication is to comprehensively compare the methods and approaches to the design of steel crane beams according to the current standards of China and Ukraine. The relevance of the work is due to the constant increase in the volume and types of cooperation between these two countries over the past decades. The subject matter is also related to the increasing use of high-strength steels in construction practice, which also have a number of additional improved performance characteristics. Methodology. To achieve this goal, we considered the design of a 6 m span steel simply supported crane beam at one of the modern energy enterprises in Ukraine. The load was assumed to come from an electric overhead crane with a lifting capacity of 25 tones. The selected cross-section was checked in accordance with the design requirements of the current standards of China and Ukraine, which together include about 20 items. Separate consideration was given to the design requirements for the arrangement of reinforcing stiffeners and ensuring local stability of the section elements. Findings. The comparative analysis of the existing approaches according to the standards of China and Ukraine has made it possible to establish that, in general, the Chinese standard imposes more stringent requirements both for the material to be used for the crane beam production and for design and construction solutions. At the same time, in terms of ensuring general and local stability, the Chinese standard uses a fundamentally different conceptual approach than the Ukrainian standard. However, the final solution has approximately the same level of bearing capacity. Originality. The comparative analysis of the requirements of the current Chinese and Ukrainian standards for the design of steel crane beams has made it possible to identify the strengths and weaknesses of each standard, as well as to outline the main fundamental differences between them. Practical value. The paper develops and proposes for practical implementation a design variant of a steel simply supported crane beam, which in terms of its bearing capacity meets the requirements of the current standards of China and Ukraine in the field of metal construction.
Green Technologies in the Design of Single-Storey Frameworks
(Dnipro University of Technology, Dnipro, 2025) Radkevych, Anatolii V.; Bannikov, Dmytro O.; Wu, H.; Lv, R.; Klochko, Leonid I.
ENG: Purpose. Analysis of the effectiveness of long-span structural systems based on glued laminated timber for a single-storey frame of a public building. Methodology. The study used a set of research methods, including scientific analysis and synthesis of available technical information on the use of modern wood products for the design of load-bearing frames of buildings with large spans. Computer modelling methods based on the numerical method of structural mechanics – the finite element method – were also used. The analysis of the structural options was performed using the finite element method using the SCAD (Ukraine) design and computing complex. A separate area of work involved design development, which included methods of engineering assessment of the accuracy and reliability of the results obtained, as well as the execution of design documentation. Findings. For the considered structural variants of the equipment compartment frame covering, stress-strain state patterns, as well as natural frequency spectra and vibration modes, were obtained. The structural variant of the frame recommended for practical implementation is based on the set of technical and economic indicators involves the use of an arched covering system. It is also shown that the use of biocomposite glued beams opens up reserves for reducing the material consumption of the structure by preliminary estimates up to 25 %. Originality. The conducted research studies allowed estimating in complex the static and dynamic load-bearing capacity of a large-span frame using glued laminated timber. The high efficiency of the combined frame system, especially in the case of biocomposite timber, has been proven. The obtained frequency spectrum is discrete and lies in the lower frequency range of 1.5‒5.0 Hz. Practical value. The use of glued and biocomposite timber beams for load-bearing elements of single-storey frames opens up a direction of green technologies for specialized buildings, such as a Fire Station. In combination with modern finishing materials such as fire-resistant wood wool, this allows increasing the operational qualities of wooden structures.
Modern Designs of Arch Load-Bearing Systems of Public Buildings
(Український державний університет науки і технологій, Дніпро, 2025) Radkevych, Anatolii V.; Bannikov, Dmytro O.; Ma, Jianchun C.,; Liu, S. W.
ENG: Purpose. The main purpose of the publication is a comparative analysis of the structural variants of the load-bearing arch system for public buildings with insulated covering. The relevance of the work is associated with the modern trend of creating public buildings of various types without internal intermediate supports. The subject of the work is also due to the desire to apply for this purpose known arch systems, which allow to significantly improve the architectural and aesthetic indicators of the building. Methodology. To achieve this goal, a project of a grocery and non-food store located in the Lviv region of Ukraine was considered. A circular steel arches with a span of 17.5 m and a sweep angle of 90 º is the basis of its supporting frame. During the analysis, a comparison of different types of arch cross-sections was performed – welded and rolled I-beam, welded rectangular pipe and seamless round pipe. The finite element method based on the SCAD design and computing complex (Ukraine) was used for the re-search. Findings. The comparative analysis made it possible to determine the geometry of the most rational constructive solution for the given conditions in the form of an I-beam welded cross-section. All other types of cross-sections considered have a lower level of efficiency and manufacturability of manufacture. Additionally, the main «weak» points of such a cross-section were identified and recommendations were given for their elimination. Originality. It consists in the fact that the comparative analysis made it possible to assess the possibility of using an arched load-bearing system as a load-bearing element of an unsupported frame of a public commercial building with an insulated roof structure. Practical value. It consists in the fact that a structural solution of a small-span steel arch in the form of a welded I-beam has been developed and proposed for practical implementation, which turns out to be approximately 1.5 times less material-intensive than possible analogues. The nature of the distribution of the materi-al efficiency coefficient for given construction conditions has also been obtained.
Modernization of the Power Supply System Applying Solar Cells and Batteries
(MATEC Web of Conferences, 2024) Serdiuk, Tetiana M.; Serchenko, Maksym; Radkevych, Anatolii V.; Serdiuk, Svitlana; Skalko, Viktor
ENG: In this paper, an assessment was made of the installation of solar panels as a backup power source for the Post of electric centralization. The advantages of using this system and an example of calculations for the Post of electric centralization were given. The norms of electricity consumption were analyzed.
Nonuniform Stress State of a Hoisting Shaft Lining as a Result of Disturbance of the Ground Freezing Technology
(EDP Sciences, 2019) Tiutkin, Oleksii L.; Miroshnyk, Vitalii; Radkevych, Anatolii V.; Alkhdour, Ahmad M.
ENG: Abstract. The paper deal with the defining stress state of a hoisting shaft lining, lying in the sandy loam, when performing and disturbing the ground freezing technology. The relevance of the performed research lies in the fact that at nonuniform freezing or defrosting, nonuniform stress state is formed, which causes a significant over-stresses of the lining. To research the nonuniform stress state, a spatial finite element model of a hoisting shaft was developed, in which the case of nonuniform ground freezing was simulated. The calculation by the finite-element technique was carried out on the basis of the computational professional complex Structure CAD for Windows. In the course of the analysis, the values of stress state for linings made of reinforced-concrete blocks, B30 concrete, gray and modified castiron tubbings. A comparison of the components of stress state for sandy loam at a temperature of -2 °C (freezing), nonuniform freezing and at a temperature of + 8 °C (defrosting) was carried out. It was found that for the proposed geotechnical conditions in the form of soft, water-saturated sandy loam, it is recommended to use a lining made of gray and modified castiron tubbings.
Overview of Technologies For Constructing the Facilities at the Dnister Pumped Storage Power Station
(Dnipro Polytechnic (National Mining University), Dnipro, 2019) Radkevych, Anatolii V.; Petrenko, Volodymyr D.; Tiutkin, Oleksii L.; Horbatiuk, Yurii M.; Parinov, V.
ENG: Purpose. Perform an overview of the construction technologies and substantiate the effectiveness of the Ukrainian experience in building a pumped storage power station (PSPS) on the Dniester River in difficult engineering-geological conditions with the construction of large underground structures, including mine shafts and hydraulic engineering tunnels. Methods. In the work, the main technological methods have been studied and analysed of hydraulic engineering construction of complex large underground structures in the rocks with medium hardness according to M.M. Protodiakonov scale using a special method of a well lowering and a combined method of drilling and blasting operations during mine workings drivage, which is based on the slow and short-delay blasting. The anchors calculation, when driving the water sup-ply conduits, has been made from the condition of suspending the block of disturbed rock, the thickness of which was taken equal to the roof arch height according to M.M. Protodiakonov. The parameters of the sprayed plaster base concrete have also been calculated according to V.M. Mostkov theory. Findings. The analysis of the current state of research, theoretical positions and world practice of construction of PSPS has been made, which testifies the high potential of this type of energy facilities. The efficiency of the underground hydraulic engineering construction of the Dniester Station has been substantiated. The results are presented of a complex application of mining and construction methods, as well as processing equipment for the construction of horizontal and tailrace conduits, drainage adits and vertical mines for hydraulic units in difficult engineering and geological conditions. As a result of performed analytical studies, the combined method of constructing the anchor support of sprayed plaster base concrete, when driving the water supply conduits, which is the most rational for engineering and geological conditions of increased complexity, has been substantiated. Originality. The efficiency of the lowering well method in a thixotropic jacket when constructing in the soft soils has been deter-mined under the conditions of building a PSPS on the Dniester River. The step-by-step combined method of constructing the anchor support of sprayed plaster base concrete, when driving the water supply conduits has been substantiated. Practical implications. The most rational ways of conducting a range of mining-construction works have been substantiated and implemented, allowing to construct a complex pumped storage facility with a capacity of over 2.0 million kilowatts, ensuring a significant increase in the power supply capacity of the West Ukraine region.
Parametric Analysis of a Strain State of a Soil Base Strengthened with Vertical Elements
(Dnipro University of Technology, 2024) Tiutkin, Oleksii L.; Radkevych, Anatolii V.; Dubinchyk, Olha I.; Kharchenko,Vitalii
ENG: Purpose is to identify vertical displacements of the “soil base strengthened with piles or micropiles based upon drilling-mixing technology” system relying upon parametric analysis of strain state of the mentioned system, and arrangement of the strengthening elements. Methods. Mathematical modeling took place for twelve finite-element models using the computing complex SCAD intended to analyze strength of structures by means of finite-element method. Numerical analysis was carried out with variation of elastic-strain modulus of vertical reinforcing elements and change in distance between them (3d and 6d of micropiles). Findings. Results of parametric analysis have been obtained for a model without a micropile (non reinforced soil base); a model with a single micropile; a model with two micropiles where distance between them is 1.5 m, i.e. 3d of micropiles; and a model with two micropiles where distance between them is 3.0 m, i.e. 6d of micropiles. The performed comparative analysis has made it possible to obtain the results proving the hypothesis by the authors as for the specific nature of vertical displacement formation of the “soil base strengthened with piles or micropiles based upon drill-mixing technology” system. Originality. It has been identified for the first time that basing upon the standardized document for the auger or displacement piles, it is impossible to decrease efficiently vertical displacements while approaching micropiles since distance between the micropiles is 3d for elements, developed on the basis of the drilling-mixing, is minimal. Practical implications. The obtained results of a strain state may become the keystone for the development of the generalized strain theory of the composite “soil base strengthened with piles or micropiles based upon drilling-mixing technology” system as a medium differing in minor changes of strain characteristics.
The Parametric Analysis of the Supported Circular Working Interacting with the Layered Massif
(IOP Publishing Ltd, 2022) Alkhdour, Ahmad M.; Radkevych, Anatolii V.; Tiutkin, Oleksii L.; Bondarenko, Nataliia
ENG: The underground construction is based on effective and rapid building of running tunnels that connect stations. The most effective technique of building is shield-driven tunneling. It is based on the application of a tunneling shield, it means, a special aggregate that excavates the ground and builds support. Even with the fact that it holds a surrounding massif, in the weak and layered rocks it is possible the formation of subsidence trough, namely, significant deformations of the daylight area. The solution of this geomechanical problem is possible on the basis of the parametric analysis of the supported circular working interacting with a layered massif. The results of the parametric analysis allow to predict deformation in the "tunneling shield – support of tunnel – surrounding massif" system. For the parametric analysis, the authors use a numerical method of finite elements based on the complex Structure Computer-Aided Design. The calculations of six supported workings with a variation of the properties of a layered massif are carried out. The results of the stress-strain state allow introducing the matrix of parameters into the prediction calculations, enabling quickly and effectively analyze the possible change in the material of support and provide recommendations for the technology of shield-driven tunneling.
Prediction of the Stress-Strain State of Circular Workings in a Layered Massif by Scaling
(EDP Sciences, 2020) Alkhdour, Ahmad M.; Radkevych, Anatolii V.; Tiutkin, Oleksii L.; Bondarenko, Nataliia
ENG: The scientific and technical task for determining the stress-strain state of mine workings is complicated by the presence of a layered massif. This task assumes particular importance in the case of circular tunneling. During its operation, it is important to predict the change of the stress-strain state for the massif or to carry out the prompt determination in the change of stresses and displacements for the unsupported working. The solution of this geomechanical task allows performing geometrical matching of the working, ensuring its strength and stability in the layered massif. A numerical finite element method based on StructureCAD (SCAD) software package was used to solve it. Four geomechanical systems were calculated: "unsupported working – layered massif". Owing to the obtained results, graphs of stresses and displacements were constructed, which allow to determine these parameters for workings with different geometric parameters and χ-parameter characterizing the ratio of the elasticity modulus of the matrix and the layer. Obtained regularities of change of stresses and displacements for the unsupported working when zooming made it possible to introduce scaling-parameters, which are a dimensionless ratio of the radii for a real system and a system with a unit diameter.
Problems of Development of an Underground Transport Infrastructure of Cities
(The Silesian University of Technology, Faculty of Transport. Katowice, Poland, 2020) Pshynko, Oleksandr M.; Radkevych, Anatolii V.; Netesa, Nikolay I.; Netesa, Andrii M.
ENG: Summary. The goal of this article is to determine rational constructional and technological options for the development of underground space, in particular, the arrangement of underground parking lots under the specific hydrogeological conditions of Dnipro city. In this article, the best practices in the construction of similar facilities in the world are discussed. Arrangements for individual structural elements and structures as a whole were considered. The main resources for their implementation are determined, the most important performance indicators are calculated, their comparison is carried out and proposals for the use of individual technological concepts are developed. The experience of underground space development in Dnipro city is studied and the problems of construction of underground structures under specific difficult hydrogeological conditions are identified. The proposed technological concepts make it possible to implement such design solutions under difficult hydrogeological conditions with dense development and preservation of historical buildings in the city.
Rational Compounds of Low-Strength Concrete with Improved Coefficient of Efficiency of Cement Use
(Trans Tech Publications LTD, Switzerland, 2019) Netesa, Andrii M.; Netesa, Nikolay I.; Radkevych, Anatolii V.; Yakovliev, Serhii O.
ENG: Abstract. The purpose of the research findings, given in article, is aimed to determine the rational compounds of concrete with an average cubic compressive strength less than 20 MPa with minimum required expenditures of cement. To reach the goal, mathematical planning of the experiment was used with variability of cement consumption from 90 to 190 kg / m3 in the compositions of the concrete mixture, and for the fine-grained filler from tails of processed ores, the consumption was like at 100 to 400 kg / m3. The result of processing experiments has shown us the dependences of the change in strength and coefficient of efficiency of the use of cement of the factors involved. Optimized values increase most intensively with minimum cement consumption and a change in the consumption of fine filler within the limits of the study. The highest coefficient of efficiency of use of cement is expressed by the ratio of the achieved strength per unit mass of used cement in the concrete mix and it was obtained at a cement consumption of 90 kg / m3 and a filler of 400 kg / m3. Using the obtained dependences of optimized values on the factors under study, the composition of concrete may be predicted with a strength up to 20 MPa with the required amount of filler.
Regularities of Stress State of Unsupported Working Occurring in a Layered Massif
(EDP Sciences, 2019) Tiutkin, Oleksii L.; Petrosian, Nataliia K.; Radkevych, Anatolii V.; Alkhdour, Ahmad M.
ENG: Abstract. The paper defines the regularities of stress state of unsupported working occurring in a layered massif. The relevance of the performed research is substantiated by the importance of determining the stresses of the contour of unsupported working when the elastic modulus of the matrix and the layer is varied. Since the application of analytic methods for this case is complex, we used a numerical finite element method, implemented in the SCAD. We developed a finite-element model of the above working, where the elastic moduli of the matrix and the layer varied greatly, while its position was unchanged (the layer laying in the middle of the working). The results of the numerical analysis allowed us to build the regularities of three stress components. In order to normalize cases of elastic modulus variation, a dimensionless χ-parameter is introduced which characterizes the relation between the elastic modulus of the matrix and the layer. The obtained regularities of the stress state of the χ-parameter have a functional character and allow to determine the stresses on the contour of the unsupported working, depending on the relation between the elastic moduli of the matrix and the layer for all possible spectrum of these parameters.
Regularities of the Stress State of the Rock Massif Around the Single-Vault Station under Construction by NATM
(IOP Publishing Ltd, 2022) Radkevych, Anatolii V.; Tiutkin, Oleksii L.; Kuprii, Volodymyr; Tkach, Taisiia
ENG: Subway stations are underground facilities of high responsibility. The use of new construction technologies requires their scientific justification. The single-vault station "Teatralna" of the Dnipro Metro is designed as one that is under construction by the New Austrian tunneling method. Since this type of station is a working of a large cross-section, it is necessary to determine the stress state of the rock massif, which affects the temporary fastening. The finite-element model is developed, which shows the stages of cross-section opening. The developed model reproduces the layout of the subway station in the rock massif and the characteristics of the temporary fastening. The numerical analysis for six stages of station construction is carried out. The distributive features of horizontal stresses and the asymmetry of the stress state of the rock massif are clarified. For the first time, the regularities of the rock massif around the single-vault station under construction by the New Austrian tunneling method are obtained. It is established that the maximum of horizontal stresses appears at the stage of opening the lower left part of the cross-section.
The Revised Method for Calculating of the Optimal Train Control Mode
(Warsaw University of Technology, Poland, 2019) Zhelieznov, Konstantyn I.; Akulov, Artem S.; Zabolotniy, Oleksandr M.; Ursulyak, Lyudmila V.; Chabanuk, Evgenij V.; Shvets, Angela O.; Kuznetsov, Valeriy; Radkevych, Anatolii V.
ENG: Development of a method for calculating the optimal mode of conducting a train in terms of energy saving meet the safety requirements and schedules. The method of calculation must solve the assigned tasks without significant time spent on the calculation. To implement this method of calculation was used a simplified model of the train as a controlled system. The existing mathematical and algorithmic methods for solving isoperimetric problems of finding the optimal solution in the presence of restrictions on resources were the information base for methodology development. Scientific works of domestic and foreign scientists, professional periodicals, materials of scientific and practical conferences, methodical and normative materials, currently in force on Ukrainian Railways. The results of these studies were used to create simulators on the basis of computer technology for the training of locomotive drivers. The scientific novelty of the proposed calculation method consists in applying the simplified calculations of the status of the train as a controlled system, without the use of differential equations of motion that allows to significantly increase the speed of the calculations. This, in turn, will solve the problems of finding optimal control in real time, taking into account changing conditions during the movement of the train. The practical significance of the obtained results is the use of such a calculation method that does not require significant time for its implementation and can be used as a subsystem of the on-board train control system capable of per-forming calculations taking into account changes in the current train situation.
Simple Methods of Increasing the Energy Efficiency of Windows in the Reconstruction of Old Buildings
(SHEE “Prydniprovska State Academy of Civil Engineering and Architecture”, Dnipro; Slovak University of Technology, Bratislava, Slovakia, 2018) Nikiforova, Tetiana; Sopilniak, Artem; Radkevych, Anatolii V.; Shevchenko, Tetiana
ENG: The installation of an additional window frame for enclosing translucent structures increases heat transfer resistance, reduces heat loss, prevents the formation of condensation on the window and the formation of fungus on the surface of slopes.
Step-by-Step Analysis of the Condition of the Side Tunnel for a Pylon-Type Metro Station under Construction NATM
(IOP Publishing Ltd, 2026) Radkevych, Anatolii V.; Kuprii, Volodymyr; Dubinchyk, Olha I.; Mazorchuk, Volodymyr F.
ENG: This scientific research provides a step-by-step analysis of the condition of the side tunnel for a pylon-type metro station with combined lining. An analysis of the algorithm for applying the New Austrian Tunneling Method to the construction of underground structures in hard rocks (as in the Dnipro Metro) has been conducted. It is justified that the analysis of the stress-strain state in the combined lining for the side tunnel of a station should be carried out in accordance with the stages of opening the working and installing the combined lining. A finite element model has been developed to represent the stages of side tunnel construction. This model also reflects the station structure’s conditions, its dimensions, and the interaction between the combined lining and the surrounding rock massif. The dependences of horizontal stresses in the rock massif and the bending moment in the combined lining on the stage of construction of the side tunnel have been obtained. The conclusion from the step-by-step analysis in the construction of the side tunnel for a pylon-type metro station, built using the New Austrian Tunneling Method, is that maximum stresses and force factors occur during construction rather than during the operational phase.
Sustainable Housing and Human Settlement
(SHEE “Prydniprovska State Academy of Civil Engineering and Architecture”, Dnipro; Slovak University of Technology, Bratislava, Slovakia, 2018) Nikolaienko, Stanislav; Kulikov, Petro; Pshinko, Oleksandr M.; Savytskyi, Mykola V.; Radkevych, Anatolii V.
ENG: This monograph presents the approaches and tools for green building, research results of assessment the potential of Europe for preservation and renovation of natural recourses to create the sustainable environment for life and industrial activity. New architectural, structmal and technological systems for construction low-rise buildings with using diffrerent materials have been considered and proposed. In the book, the technologies of energy efficient building design and construction are described. lt can be used as Urban Agenda for Regions' Sustainable Development. For researchers, university students, municipal administration, managers of business structures. This monograph was prepared with support of the Ministry of Education and Science of Ukraine in the framework of project "Scientific bases for creation of construction and agrarian clusters with a closed cycle of material and energy flows" (from 01 .01 .2017 until 31.12.2018, No. of state registration 0117U000367).