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Analytical Method for Compiling and Applying a Ballast Map for the Traction Unit PE2U
(НВП ПП «Технологічний Центр», м. Харків; Українська державна академія залізничного транспорту, м. Харків, 2019) Bannikov, Dmytro O.; Radkevich, Anatolii V.
ENG: Under practical operation, electric locomotive traction units of series PE2U quite often require, especially in recent decades, various kinds of repair, necessitating the restoration of fleet of these machines that are rather worn-out. That changes the most important indicator in the work of the machine ‒ the distribution of masses; the resulting imbalance of the machine can reach 30 %. Further operation of such a locomotive leads to a decrease in its traction by 40‒100 kN, shortens the service life of the undercarriage by 8‒10 years on average, as well as requires that the speed of the machine during operation should be reduced by 10‒15 km/h. Given the lack of an appropriate regulatory framework and of recommendations in the specialized literature, such balancing operations are actually performed iteratively, with an arbitrary arrangement of ballast elements, which often delays the duration of operations and leads to their poor quality. One of the possible solutions to resolve this issue is the development and implementation of a special theoretical method that would make it possible to analytically substantiate the proposed structural-technological solutions related to the arrangement of a ballast at the electric locomotive traction unit PE2U. In this case, the ballast is composed of individual small-size elements that are stacked in rows into existing structural cavities in a bearing frame. The result is a compiled so-called individual ballast map for each machine. The proposed approach includes two stages of calculations and makes it possible to not only obtain practically acceptable ballast location diagrams, but to also significantly reduce the number of weighings required for the machine. The approach has been tested on several machines at electric locomotive traction units of PE2U over 2010‒2012 and could be officially used in the specialized regulatory documentation. Its practical error does not exceed 3 % and is mainly predetermined by technological factors.
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.
Carbon Materials for Electrically Conductive Concrete
(EDP Sciences - Web of Conferences, France, 2024) Savytskyi, Mykola V.; Sukhyy, Kostyantyn M.; Savytskyi, Oleksandr M.; Babenko, Maryna; Shevchenko, Tetyana
ENG: In recent decades, the direction of building materials science related to the creation of Smart Concretes has been rapidly developing. Smart Concretes, in addition to the functions of a structural material, also perform other functions that are related to their new properties. Among the large number of Smart Concretes, it is necessary to highlight Electrically Conductive Smart Concrete. This type of concrete is obtained by adding conductive fillers to the concrete mixture. Among them, carbon materials are the most promising in terms of their properties. Despite the large number of conducted studies of conductive fillers and conductive concrete, there is still no generalization and systematization of them. In addition, there are no standards for testing the conductive properties of both fillers and concretes. Therefore, the authors aimed to systematize data on Electrically Conductive Smart Concrete, as well as electrically conductive carbon fillers. A method for testing the electrical conductivity of Carbon Nanomaterials (CNMs) as fillers for Electrically Conductive Concrete is proposed. Approbation of the proposed method was carried out by determining the electrotechnical indicators of carbon fillers, such as coke breeze and carbon black.
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.
Comprehensive Study of the Microclimate Parameters in the Residential Building
(Sciendo, Poland, 2021) Yurchenko, Yevhen; Kuznetsov, Valeriy; Radkevich, Anatolij V.; Koval, Olena; Skrzyniarz, Marek; Kruczek, Włodzimierz; Mike, Kamil; Mroczkowski, Łukasz
ENG: The relevance of the research lies in the development of the current question about the influence of microclimate quality on the efficiency of residential units. The aim of the study is to examine how the microclimate parameters affect the efficiency of residential buildings. Findings. The results obtained are essential for the design of energyefficient and comfortable residential buildings. The scientific novelty and practical importance of research resides in the thorough study of microclimate in low-rise residential buildings. Microclimate deviation charts for residential buildings have been produced.
Controlling the Dynamic Characteristics of Steel Bunker Containers for Bulk Materials
(IOP Conference Series: Earth and Environmental Science, 2024) Bannikov, Dmytro O.; Tiutkin, Oleksii L.; Hezentsvei, Yukhym; Muntian, Antonina O.
ENG: The article presents the main results of research devoted to the definition and analysis of the dynamic characteristics of steel small-sized bunker containers for storing bulk materials. All studies were carried out using the finite element method with the use computer complex SCAD. The object of research was a bunker of a bypass track for feeding bulk materials with a total volume of up to 70 m3. The study analysed the natural partial frequency spectrum and the partial oscillation modes of individual load-bearing elements of the bunker. Based on the results of the data analysis, a rather high quantitative density of the natural frequency spectrum was determined. At the same time, its lower limit is about 25-30 Hz for an empty bunker capacity and decreases to 3-5 Hz when the bunker is fully loaded, which is dangerous from the point of view of the possibility of resonance phenomena. In order to qualitatively and quantitatively control the dynamic characteristics, it was proposed to change the steel strength of the structure, which made it possible to change the natural frequencies by about 15% for every 100 MPa change in steel strength for the bunker containers of the considered type.
Costs of the Human Capital and Development of the Social Potential in Accounting System for Central and Eastern Europe
(Oxford University Press, 2020) Pshynko, Alexander N.; Golovkova, Lyudmila S.; Kolomiiets, Viktoriia M.; Dobryk, Liliia O.
EN: Nowadays, human capital and social potential become the most valuable resource for the harmonious development of the national economy. Expenditure on human capital and social development should occupy a significant part in the state budgets of countries. Therefore, accounting of such expenses is extremely important. The purpose of the study is to reveal the possibility of accounting for expenditures on the human capital and social potential development in the accounting system of the Central and Eastern Europe, provide recommendations for the current accounting system. The research revealed the plurality and ambiguity of the interpretation for the categories «human capital» and «social potential». The regulatory and legislative uncertainty complicates the accounting of the human capital costs and development of the social potential. These categories must be defined by law. As per normative and methodological basis for the accounting of the human capital, it would be better to apply the International Financial Reporting Standards. The absence or misrepresentation of information about available human capital are contrary to IFRS requirements and reduces or exaggerates the value of the organization. It is offered in IFRS, to provide a comprehensive accounting of the cost for the human capital and developing social capacity. The budget of the Central and Eastern European countries includes only the costs of social protection, health, education, recreation, culture, religion. After the budget analysis was conducted, the authors proposed to develop new objects of accounting (human capital, social potential), accounting standards for it. A part of the GDP expenses should be directed to the financing of the human capital expenditures and social potential development.
Design Features of Protective Anti-Drone Shields
(Odessa State Academy of Civil Engineering and Architecture, Odesa, 2025) Bannikov, Dmytro O.; Misiura, Yevhen A.
ENG: The paper examines the structural and engineering aspects of designing steel protective screens to counter unmanned aerial vehicles (UAVs) at energy infrastructure facilities. The relevance of the topic is due to the targeted UAV attacks on transformer substations, which have prompted the implementation of passive protection in the form of steel anti-drone screens. The study includes an analysis of recent research and publications on UAV threats to power grids and existing protection methods. It explores structural solutions for protective screens and presents the results of their practical implementation in Ukraine. The paper summarizes design requirements, including material selection, ensuring appropriate screen height and distance, modularity, and maintainability of the structure.
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.
Determining the Rational Compositions of Low-Strength Concretes
(НВП ПП «Технологічний Центр», Харків, 2019) Shishkin, Alexsander; Netesa, Nikolay I.; Netesa, Andrii M.
ENG: The paper reports regularities in the influence of the amount of waste from iron ore enrichment at a rational composition of grain components on strength of concretes with a minimal cement consumption. Low-strength concretes are used in the non-reinforced structures, so they are not subject to the requirement for the minimal cement consumption in order to ensure the protection of reinforcement against corrosion. A significant reduction in cement consumption by low-strength concretes while maintaining the required strength can be ensured by a rational grain composition of the components of a concrete mixture, which is characterized by the ratio between large, medium, and small components of 52:23:25. In such formulations, the required amount of fine-grained component is achieved by introducing the fine-grained components, made, for example, from the secondary products of industry, specifically the iron ore dressing waste. The result of the research conducted established that ensuring the rational grain composition of the concrete mixture components provides for the required low strength of concrete at a significantly less cement consumption than that for concretes whose composition is defined in line with other procedures. It was found that it is advisable to use the iron ore dressing waste as a fine-grained supplement, the introduction of which at rational amount ensures significant improvement in the efficiency of cement utilization in concretes of low strength. Application of concretes of the proposed formulations, which could be used for temporary structures ‒ a concrete cap for making floor slabs at formwork-free molding, could save a significant amount of cement, and dispose of the secondary products from industry. The research has also established that the use of plasticizers makes it possible to obtain concretes of the rational grain composition with the required workability.
Development of Dynamic Integral Evaluation Method of Technical State of One-Section Electric Locomotive Body
(НВП ПП «Технологічний Центр», м. Харків; Українська державна академія залізничного транспорту, м. Харків, 2020) Bannikov, Dmytro O.; Yakovliev, Serhii O.
ENG: At present, one of the main problems arising from the long-term operation of one-section electric locomotives is the need to maintain their good technical condition. In this case, the determining aspect is often rapid identification of existing defects and damage to the main bearing structural elements of machine bodies, as well as preventing their development into more serious structural deviations. The aim of the study is to develop a specialized method that allows identifying defects of the main bearing structural elements of the bodies of one-section electric locomotives at the early stages of emergence and development. This method of dynamic integral evaluation is based on the analysis of partial dynamic spectrum of the electric locomotive. Based on the magnitude of the spectrum deviation relative to the theoretical one obtained from finite element modeling, it is possible to determine the approximate nature and location of damage, especially latent. The frequency spectrum of the main bearing structural elements of the bodies of one-section electric locomotives obtained in the course of the studies is rather dense and lies in the frequency range up to 20 Hz. The presence of damage reduces its value, and for the most common types of defects, this reduction is 25–30 %. The effectiveness of the practical application of the dynamic integral evaluation method is illustrated by the example of the DS3-008 machine. The method revealed hidden damage to one of the elements of the bearing frame of the front surface of the cab, which was not revealed during the standard maintenance procedure of the machine. The use of the method of dynamic integral evaluation of the technical condition of electric locomotives is quite versatile and can also be recommended for other units of railway rolling stock. In practice, the introduction of this approach will effectively prevent the development of emergencies.
Development of Test Methods in the Process of Electrically Conductive Concrete Production
(IOP Publishing Ltd, 2024) Savytskyi, Mykola V.; Pang, Weixiang; Sun, Lijun; Savytskyi, Oleksandr M.; Bordun, Maryna; Li, Yang; Xia, Yanfang; Wang, Haojie
ENG: Prevention of climate change, implementation of sustainable development principles in building industry, creation of Green buildings, Three-zero buildings (zero energy, zero emissions, zero waste), energy independent buildings maybe on the base of Smart Concrete. Electrically Conductive Concrete as type of Smart Concrete have the possibilities to create multifunctional hybrid structures for various purposes. The production of electrically conductive concrete is usually based on the introduction of carbon materials and carbon nanomaterials (CNMs) as electrically conductive fillers into its concrete composition. The theory of conductive percolation is used for design of electrically conductive concrete. To select electrically conductive carbon filler, it is necessary to summarize their electrically conductive characteristics. Today, there is no standard for determining the electrical conductivity of carbon fillers, nor is there a method for designing the composition of electrically conductive concrete; the development of both is imperative. Features of the preparation of electrically conductive concrete with hydrophobic carbon nanoparticles prone to aggregation are indicated. To obtain high quality electrically conductive products an operating system for quality control at the stages of the technological process of manufacturing must be proposed. Homogenization of the electrically conductive filler is very important. It is necessary to propose a method for assessing the stability of an aqueous suspension of a hydrophobic carbon material used for homogeneous distribution of a filler. Due to the lack of a standard, a method for determining the electrical conductivity of concrete is also needed.
Dynamic Properties of Large-Sized Steel Bunkers for Bulk Materials
(IOP Publishing Ltd, 2025) Bannikov, Dmytro O.; Polozhechko, Olha
ENG: The article presents the results of a dynamic analysis of the structure of a large-sized steel bunker of the Kryvorizhstal plant (Ukraine). The overall dimensions of the bunker are 18 by 15 m in plan with a total height of about 9 m and a net volume of about 1000 m3. The studies were carried out using the finite element method based on the construction-oriented software product SCAD (Ukraine). Variants of the dynamic analysis of an empty structure, as well as structures with a level of loading with bulk material of 12.5%, 25%, 37.5%, 50%, 62.5%, 75%, 87.5% and 100% were considered. As a result, it was found that the frequency spectrum of the steel bunker is quite dense and quantitatively starts at a frequency of about 10 Hz. An increase in the level of bunker loading for every 25% of capacity leads to a decrease in the frequency spectrum by 20-30 % on average. This regularity makes it possible to develop and implement an automated system for controlling the frequency spectrum of unloading devices at the Kryvorizhstal plant.
Dynamic Properties of One-Storey Industrial Building
(Дніпровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпро, 2020) Rozumenko, D. V.; Bannikov, Dmytro O.
EN: Purpose. Recently, there has been a growing demand in Ukraine for the reuse of industrial buildings that have not been in exploitation for a certain period of time. At the same time, there are frequent cases when new technological equipment transfers significant dynamic loads to existing structures over a long period of time. Since the available data regarding the dynamic properties of industrial buildings are now practically absent, the main goal of the studies made by the authors is to evaluate and analyze own dynamic characteristics of a one-storey industrial building. Methodology. To achieve this goal, it was necessary first to choose the type of industrial building, which is common enough for the formulated conditions of the reuse possibility. A one-storey unheated industrial building with three purlins (purlins 15 + 15 + 6 m) with a steel supporting frame was taken as such a building. In the course of research, the cross sections of the main load-bearing elements were varied, as well as the schemes of their connection with each other. The calculations were carried out by the finite element method based on the Lira for Windows project complex. Findings. The obtained frequency spectra of the own dynamic characteristics for the main bearing structural elements of an industrial building of the type in question are in the range up to 30 Hz. Also, during the research, dependencies were obtained for changing this range for various cases of design decisions of the building. Originality. The research results presented in the publication make it possible to evaluate the range of the own dynamic characteristics of single-storey multipurlined unheated industrial buildings with the traditional structural solution of the steel frame. Practical value. The resulting range of the own dynamic characteristics of the industrial building of the type in question is quite dangerous for human health. The most unfavorable is the oscillation form of the columns, which actually involves the entire structural frame. Therefore, in the course of research, a special method was developed and tested to stabilize such vibrations «on the base» using flexible ropes.
Effect of the Iron-Containing Filler on the Strength of Concrete
(НВП ПП «Технологічний Центр», Харків, 2017) Shishkin, Alexsander; Netesa, Nikolay I.; Scherba, Vladimir
EN: The purpose of present research is to determine the impact of a mixture of river and technogenic sand containing iron compounds in the presence of plasticizers on the strength of fine-grained concretes. As a result of the performed research it was established that the technogenic sand, representing mineral complexes containing iron compounds, interacts with Portland cement minerals and the products of their hydration. The studies we conducted showed the possibility of targeted regulation of the processes of formation of structure of finegrained concretes by joint application of mineral complex with iron ions, river sand and surface-active substances that are substantially different in the structure of molecules. It was established that using a mixture of river and technogenic sand containing iron compounds in the form of a fine aggregate leads to a significant increase in concrete strength. There is a certain ratio between river sand and the technogenic sand containing iron compounds, which provides concrete with the largest strength. An optimal content of the technogenic sand in a fine aggregate depends on the type and amount of minerals within its structure, and the content of particles with different size. It is demonstrated that the effectiveness of using modern superplasticizers in fine-grained concretes increases considerably with the introduction of mineral complexes containing ions of iron to the compositions of concrete.
Effectiveness Evaluation of Steel Strength Improvement for Pyramidal-Prismatic Bunkers
(OÜ «Scientific Route», 2020) Hezentsvei, Yukhym; Bannikov, Dmytro O.
EN: In accordance with the recommendations of specialized professional literature, steel pyramidal-prismatic bunkers are projected for a service life of 20 years. However, in practice this term is often twice, or even three times lower. This is especially true for complicated operating conditions, in particular the effect of increased loads and low temperatures. Existing design techniques for such structures, both in European practice and the design practice of Ukraine and other CIS countries do not pay attention to these aspects. Therefore, in the practice of operation, the increased accident rate of steel bunker capacities has already become virtually a common occurrence. One of the possible ways to solve this problem is presented, which consists of using instead of traditional steels of ordinary strength with high plastic properties, steels of increased or high strength with reduced plastic properties. At the same time, clear theoretical recommendations are provided for choosing the right steel depending on the operating conditions, primarily when exposed to increased loads. The recommendations are presented in a form convenient for practical engineering applications. The proposed approach allows to reduce the material consumption of structures of this type on average according to theoretical estimates by 25-30% without reducing their bearing capacity. Their durability is also further enhanced by improving performance at low temperatures. Thus, the applied aspect of such a solution to this above problem is the possibility of increasing the overall reliability of steel bunker capacities, as well as reducing the cost of their periodic maintenance and repair work. A practical illustration of the presented approach is also given on the example of the design of bunkers of a bypass track for supplying charge materials for blast furnaces of one of the metallurgical plants of the northern location. As a result, this created the preconditions for monetary savings of about 0.5 million UAH in prices 2019 (about 20,000 USD)
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 %.
Experimental evaluation of Strength and Deformability of Steel Nails for Wooden Structures
(Український державний університет науки і технологій, Дніпро, 2026) Bannikov, Dmytro O.; Bakan, I. M.
ENG: Purpose. The main purpose of the paper is to discuss the experimental studies to determine in laboratory conditions the characteristics of nail steel of one of the most common companies on the modern construction market of Ukraine – ExpertFix (Denmark). Methodology. To achieve this goal the tests were carried out for tensile testing of nails of a classic round cross-section of 5 diameters in the range from 4 to 7 mm, manufactured according to the German standard. Findings. According to the results of the study, diagrams of the work of steel nails under load were constructed, which turned out to be very close to the classical diagram of the work of high-strength steel. The destruction of the samples occurred according to a visco-plastic scheme with the formation of a characteristic «neck» at the rupture site. The recorded strength level is from 450 to 700 MPa at a relative deformation of up to 13%. Originality. The obtained characteristics of nails correspond to high-strength steels of classes C390–C500 according to the standard of Ukraine, but do not correspond to steels of grades St1-St3, for which current theoretical approaches to the design of nodal connections have been developed. Therefore, the use of such nail products in practice requires adjustment and clarification of existing approaches and methods of their use in wooden structures, which in turn requires the intensification of scientific research in this direction. Practical value. The practical usage of the strength characteristics of steel nails obtained during experimental studies allows for the correct and reasonable design of nodal connections of wooden structures based on the current Ukrainian standard. It also provides a basis for developing more advanced calculation approaches for assessing their performance.
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.
Features of the Design of Steel Frame Structures in India for Seismic Areas
(Trans Tech Publications LTD, Switzerland, 2019) Вannikov, Dmytro O.; Radkevich, Anatoliy V.; Nikiforova, Nataliya A.
ENG: Abstract. This article is devoted to the analysis of one of the most common structural designs of the steel frame of small spans, currently used in India in construction and reconstruction for seismic areas. This scheme constructively involves the implementation of the main bearing elements - bolts and columns - in the form of a spatial truss box section. At the same time, rather simple rolling profiles from small-sized corners are used, as well as a round steel bar. The studies performed by the authors were carried out using the finite element method based on the national design computing complex SCAD for Windows. The loads, as well as the geometrical characteristics of the profiles, were taken according to the current building standards of India. Based on the results of the analysis, a number of recommendations were formulated to improve the efficiency of the considered design scheme for seismic effects of varying intensity.
Geotechnical Analysis of Optimal Parameters for Foundations Interacting with Loess Area
(EDP Sciences, 2020) Dubinchyk, Olha I.; Bannikov, Dmytro O.; Kildieiev, Vitalii R.; Kharchenko, V.
EN: The article highlights results of the geotechnical analysis of the stress and strain state for the base of a subsoil massif under its interaction with the strip foundations. The massif is represented by loess soils which while soaking give overtime subsidences that complicate the operation of a building or a structure. Through geotechnical iterative research, optimization of the parameters for strip foundations on four axes at a four-storeyed residential building is carried out. Checks are performed on two groups of limiting states for scenarios of soil occurrence in natural, moistened and compacted states. The optimum dimensions in the width of strip foundations are selected, they give approximately the same strain values of the base after the creation of the soil bedding with its layer-by-layer compaction. The relevance of this research is to develop optimal parameters in the design of strip foundations for shallow depth on subsidental loess soils.
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.
How Much Is Needed? Discussion on Benchmarks for Primary Energy Input and Global Warming Potential Caused by Building Construction
(MDPI, Basel, Switzerland, 2025) Rabenseifer, Roman; Kalivodová, Martina; Kononets, Yevhen; Mahas, Nataliia; Minarovičová, Katarína; Provazník, Robert; Bordun, Maryna; Shekhorkina, Svitlana; Savytskyi, Mykola V.; Savytskyi, Oleksandr M.; Semko, Volodymyr
ENG: The operational energy efficiency of new buildings in the EU should be at the level of ultra-low or near-zero energy buildings. It is therefore relatively difficult to achieve further energy savings. However, the pre-operational phase—raw material sourcing, manufacturing, transportation, and construction—offers significant energy savings and greenhouse gas reduction opportunities, referred to as embodied energy and equivalent CO2 emissions. Unlike operational energy, no standard or legislative criteria have yet been established for embodied energy. Setting maximum embodied energy values converted to the unit of heated building area, accounting for building shape factor, and differentiating between high-mass and lightweight constructions are proposed. This study illustrates assessing environmental indicators based on building shape, highlighting the necessity of relative assessments over absolute values to favour energy efficiency. It also emphasizes that precise criteria should derive from authentic data collected during the energy certification and building permitting processes. Integrating assessments of embodied energy and operational energy demand facilitates a comprehensive evaluation of buildings’ environmental performance.
Modelling of the Electric Locomotion DS3 Working
(Dnipro National University of Railway Transport named after Academician V. Lazaryan, 2019) Bannikov, Dmytro O.; Radkevich, Anatoliy V.; Muntian, Antonina O.
ENG: Abstract. The purpose of the work is to evaluate the spatial distribution of the rigidity of the carrier frame and the body of the Ukrainian electric locomotive DC3 as a single system during operation and repair. The research was carried out on the basis of the finite element method with the application of design and computing complex SCAD for Windows. The numerical model of the electric locomotive was built, tested and then used to identify the causes and providing guidance on solving some specific operational questions. They are included, for example, the possibility of eliminating the body skew when jacking up on jacks and jamming the door as a result. The researches showed that the structure of the electric locomotive DS3 in general has a rather high spatial rigidity, both in transverse and longitudinal directions, and on torsion. However, for some practical repair tasks there is not enough for that rigidity. It was recommended to increase the thickness of the shell of its body up to 4 mm or the roof up to 8 mm, which leads to an increasing in the total mass of the machine by about 2,5 and 3,5 tons, respectively.
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 Buffer Beam of PE2U Traction Unit Electric Locomotive
(IOP Publishing, 2020) Bannikov, Dmytro O.; Radkevich, Anatolii V.; Muntian, Antonina O.
ENG: The article presents the main results of a theoretical study on the analysis of the stress-strain state of the construction of the buffer bar of the electric locomotive for the control of the traction unit PE2U. The estimation of the possibility and effectiveness of attachment on the front wall of the buffer beam of a special securing bracket was considered as a separate task. In both cases, the finite element method based on the SCAD for Windows computing system was used. As a result, it was found that in general, the design of the buffer beam does not meet the requirements of the current standards. Up to 5 zones of high stress concentration are present in the structure, which, given the long service life of the machines (up to 40-50 years), are potential places for the development of fatigue damage. In order to balance the stress level, we recommended to strengthen the contact zone of the supports under the automatic coupling with the system of horizontal truss plates. The additional recommendation is to reinforce the lower sheet of the buffer beam structure up to and including its replacement by a sheet of greater thickness. Attachment to the front wall of the buffer beam of a special securing bracket for holding in emergency mode the coupling of the locomotive-car is possible provided that this zone is strengthened by the system of additional truss plates. The total increase in the mass of the buffer beam reaches 350 kg (25 % of the original weight of the buffer beam structure).
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.
Outlooks of Using DBN B.2.6-161:2017 «Wooden Structures» in Design Practice
(Дніпровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпро, 2019) Bannikov, Dmytro O.
EN: Purpose. From 01.02.2018, the new state standards DBN B.2.6-161:2017 were introduced into the wooden structures design practice. They replace the recently prepared codes DBN B.2.6-161:2010, which, in turn, were elaborated to replace the SNiP II-25-80. The author of this publication would like to draw the attention of develop-ers and potential users of the codes DBN B.2.6-161:2017 to the points that are not entirely clear, which at first read-ing caused him certain difficulties in terms of their practical use. Methodology. The practical experience accumu-lated by the author in the use of normative literature in educational practice, as well as the available experience dur-ing laboratory studies with students, made it possible to estimate the recently introduced codes DBN B.2.6-161:2017 from a practical point of view. Findings. In general, the new codes, recently introduced into design practice, are progressive both in their content and in terms of their use in construction practice. However, the existing problem areas in these standards, which are considered in this publication, in our opinion, can significantly limit the possibil-ity of their wide practical application. Originality. The analysis of recently introduced new standard was carried out by the author of the publication not only in terms of assessing quality requirements and recommendations, but also in terms of the quantitative aspect of the issue. Practical value. The author’s experience in calculating simple ele-ments and basic types of connections according to the new codes DBN B.2.6-161:2017 indicates that the bearing capacity determined for various cases is lower on average by 1.5 – 3 times than according to the previous codes SNiP II-25-80. From a practical point of view, this revealed discrepancy means that the already constructed struc-tures may require some reinforcement or reconstruction, and new designed structures should have large bearing sec-tions of the elements and, accordingly, large bearing capacity and weight.
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.
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.
Peculiarities of Organizational and Technological Approaches to the Post-War Restoration of Infrastructural Objects in Ukraine
(E3S Web of Conferences, 2024) Savytskyi, Mykola V.; Radkevych, Anatolyi V.; Savytskyi, Oleksandr M.; Babenko, Maryna; Shevchenko, Tetyana
ENG: As a result of russia's insidious war against Ukraine, thousands of infrastructure facilities and nergetical objects were destroyed or damaged. We are sure, Ukraine will win this war. Already today, the territories of the country freed from the occupiers with the destruction of residential and civilian buildings, infrastructure facilities need restoration. In Ukraine, the Government Plan for the Recovery of Ukraine has been developed. Ukraine's Recovery Plan is aimed at ccelerating sustainable economic growth. But this Program outlines general approaches and directions for he recovery and development of Ukraine. Therefore, it is necessary to develop detailed local rograms that contain organizational and technological approaches to the implementation of restoration works. The programs must to help local authorities, territorial communities in which housing and social infrastructure objects were damaged or destroyed as a result of russian armed aggression, to make decisions regarding the planning and implementation of restoration works and the development of territories. Purpose of the study: to develop detailed Local Program which specifies the National Programs of the Recovery Plan of Ukraine and contain organizational and technological approaches to the implementation of restoration works.
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.
Prospective Directions of the Development of Loose Medium Mechanics
(Національна академія наук Укрaїни, Київ, 2020) Bannikov, Dmytro O.; Tiutkin, Oleksii L.
ENG: At present, in the field of loose medium mechanics there is a rather serious key problem, the absence of a universal theoretical concept for considering the behavior of the loose medium under different practical conditions. Such situation significantly impedes the further development of this industry, since theoretical models of bulk material, which now have been counted about 30, practically conflict with each other. Problem Statement. In practice, such problem leads to numerous cases of failures of structures of various types, as a result of errors in determining the loads from the bulk material. Purpose. Identification and formulation of the main directions of the further development of loose medium mechanics as a separate section of soil mechanics in the composition of geotechnical mechanics. The development of these directions is a solution for overcoming the problem of creating a unified theoretical model of loose medium. Materials and Methods. The systematization and the synthesis of the accumulated information on loose medium mechanics and the development of a universal approach to describing its behavior is the main method to achieve the formulated purpose. Results. Researching in three directions is the main prerequisite for the formation of the concept of loose medium. These directions are the determination of the properties of loose materials; the determination of the pressure ratio; and the development of a model for packing grains of loose material. Conclusions. The discrete-continuum approach shall be basic concept for developing the unified theoretical model of loose medium. At the same time, all properties of loose medium are determined on the basis of its discrete nature; the equations of static equilibrium and the dynamic motion of the loose medium are formed considering it as a homogeneous continuum within a certain volume. Also, the static behavior of loose medium shall be analyzed as a partial case of its dynamic behavior rather than as an individual task with its own parameters.
Rational Altitude Structure for Placing the Wind Equipment in the Conditions of Ukraine
(Дніпропетровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпро, 2018) Savchenko, R. A.; Bannikov, Dmytro O.; Kyrpa, Ivan I.
EN: Purpose. For wind observations special wind equipment is used, which should be placed at a certain height above the ground for a relatively short period of time. Such equipment can be transferred from one region to another. Therefore, the main purpose of the studies outlined in the publication is the selection and justification of the construction of a mobile altitude structure for the placement of wind equipment in the natural and climatic conditions of Ukraine. Methodology. To achieve this purpose, first we chose the type of altitude structure from the existing ones. Next, we determined the nature of the effect of natural and climatic loads on these structures in accordance with the norms of Ukraine. After this, we performed a numerical analysis of the work of altitude structures by the finite element method on the basis of the Lira software. Also, an economic evaluation of the expediency of using altitude structures of a certain type was made, taking into account the lease of the land plot for their location. Findings. According to the results of the conducted studies, it should be noted that for the conditions of Ukraine a steel tower is the most rational mobile altitude structure for placing wind equipment for a relatively small interval of time. In comparison with a steel mast of a similar height, the total cost of its installation and operation is lower. The X-cross brace for steel towers from 50 to 60 m in height is more rational than the K-brace. Herewith, its usage decreases the construction cost almost by half. Taking into account the possibility of transportation, the separation of the steel tower into assembly units of 8-10 m in length is the most effective. Originality. The authors proposed the method for estimating the economic efficiency of choosing a mobile altitude structure depending on the natural and climatic conditions of the terrain. In accordance with this method, the most rational type of altitude structure is determined taking into account its mobility. Practical value. Application of the proposed approaches and the solutions allows reducing the time required for calculations in design practice and also more reasonably approaching the choice of design solutions for altitude structures.
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.
Rational Design of Short-Span Industrial Building Roof for Reconstruction Conditions
(Дніпровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпро, 2019) Kruhlikova, Nadija G.; Bannikov, Dmytro O.
EN: Purpose. Recently, the demand for reuse of industrial buildings that have not been in operation for some time has been increasing in Ukraine. Herewith, quite often the design of their roof requires the complete replacement and renovation by using modern roofing materials to meet the requirements of new government standards. Therefore, the choice and justification of the rational design of steel roof on the example of a short-span industrial building (18-24 m span), which is planned to be returned to exploitation after idle time, is the main goal of this publication. The object of the analysis is an unheated building equipped with bridge cranes of a small capacity (up to 10 tons). Methodology. To achieve this purpose, the comparison of structural variants of a roof steel collar tie was per-formed. Such variants include two types of collar tie cross-section – a lattice truss and a solid I-girder. The first type was analyzed for four possible types of section of elements – double angles, a roll-welded square profile, an electric-welded round tube and a rolled round tube. The second type was analyzed for two possible types of section – rolled I-section made of normal strength steel and fabricated sections of thin-gage high-strength steel. The design variants were compared on the basis of a numerical analysis of their work using the finite element method based on the soft-ware complex SCAD for Windows. Findings. According to the research results it should be stated that for the con-ditions of the city of Dnipro the most cost-effective variant of the steel collar tie cross section for the short-span in-dustrial building is the truss made of electric-welded round tubes. Also the construction of collar tie made of roll-welded square profiles or fabricated section of thin-gage high-strength steel is considered quite effective. Originality. The research presented in the publication allows estimating the possibility and economic efficiency of usage for various types of cross-sections for the collar tie of a steel non-insulated roof of the industrial building for the reconstruction conditions in the Dnipro-city. Practical value. A practical estimation of mass and cost parameters for steel collar ties of various types has been carried out, and the methodology for conducting such estimation has been substantiated.