Academic journal Industrial Machine Building Civil Engineering
Presenting the researches results in the area of building works mechanization, design and exploitation of building structures and their improvement, examining the current problems of soil mechanics, geotechnics and foundation engineering.
National University «Yuri Kondratyuk Poltava Polytechnic»
Rational design and construction solutions for the use of the foundations of demolished buildings for further reconstruction
The issues of post-war reconstruction of territories and settlements that suffered extensive damage as a result of hostilities are considered. Rational design and construction solutions are proposed that allow maximum use of the foundations of destroyed buildings for further reconstruction. It is determined that the planning solutions for the quarter development of industrial cities are imperfect and require updating in accordance with modern principles. A solution that significantly reduces the amount of work involved in dismantling the underground structures of buildings is to use them for the construction of new reconstruction objects. A combined solution is proposed for the joint use of the foundation array of a destroyed building and a monolithic grillage on bored piles. The use of diamond drilling technologies allows for the effective installation of piles in complex, swampy areas. It is proposed to construct the structure in the form of a system of soil foundation, artificial foundation, connected by a system of piles and foundation frames.
Copyright (c) 2025 Dmytro Shvydkyi, Kostiantyn Sokolenko, Valeriy Sokolenko, Vitaliy Shvets https://creativecommons.org/licenses/by-nc-sa/4.0
Strength and force distribution of lap-welded composite longitudinal reinforcing bars formed during strengthening of reinforced concrete beam elements by increasing the cross-section in the tension zone
The article experimentally investigated the strength and stress-strain state of eccentrically stretched specimens from welded overlapped longitudinal reinforcing bars, which have cross-sections varying in length and are interconnected by electric arc welding. The strength of reinforcing bars of a composite cross-section was compared with the strength of individual centrally stretched reinforcing bars. As a result of the experiment, the influence of the main factors on the strength of the bars was investigated: electric arc welding; stress concentration; eccentricity of the application of longitudinal tensile force, as well as the distribution of forces in the sections of each element along the length of the composite reinforcing bar-sample
Copyright (c) 2025 Anna Azizova, Dmytro Ovsii, Oleksandr Semko, Mykola Ovsii https://creativecommons.org/licenses/by-nc-sa/4.0
Specific aspects of vertical roller mills design selection
The article analyzes specific design selection aspects of vertical roller mills, essential for grinding materials like granulated slag in the cement and mining industries. The research focuses on improving mill’s working elements to enhance efficiency, reduce energy consumption, and increase wear resistance under harsh operating conditions. Modern innovative designs, including multi-roller and modular concepts with active redundancy, are reviewed for improved reliability. The comminution principle relies on energy-efficient compression and shear within the material bed. A comparative analysis of various mills configurations, differing in roller and table geometry, is presented, demonstrating how design adaptations such as specialized rollers for high-moisture slag optimize performance, wear rate, and energy efficiency.
Copyright (c) 2025 Mykola Klymenko, Vasyl Marach https://creativecommons.org/licenses/by-nc-sa/4.0
Development of the statistical approach to the calculation of building structures
The current method of calculating building structures by limit states (previously by allowable stresses) is essentially semi-probabilistic. Meanwhile, in parallel with this dual method, for many years, fully probabilistic (statistical) approaches to the calculations have been developed. The aim of the article is to consistently review the approaches developed over the course of ninety years to the implementation of general probabilistic methods for calculating building structures, starting from the 1930s to the present. It is emphasized that domestic specialists are actively developing probabilistic methods, the results of which are implemented in regulatory documents. The prospects of the results of this scientific direction in creating a new generation of building design standards are noted.
Copyright (c) 2025 Sergii Pichugin https://creativecommons.org/licenses/by-nc-nd/4.0
Transforming Occupational Safety and Civil Defense: Wartime Challenges and Solutions
This article is dedicated to the urgent need for a fundamental reform of traditional occupational safety and civil defense systems under the conditions of a full-scale war. It examines new, previously unseen risks to the life and health of employees caused by military actions. These threats extend far beyond conventional occupational hazards, including direct missile strikes, the destruction of buildings, cyberattacks, and a severe impact on the mental health of personnel. It is proven that old approaches to occupational safety, which focused on preventing accidents in peacetime, are completely unable to cope with the dynamic, unpredictable, and aggressive nature of military threats. The paper substantiates the urgent need to integrate civil defense measures into the occupational safety management system, transforming two separate systems into a single, holistic, human-centric safety model at the level of each enterprise. Special attention is given to how digital technologies, particularly artificial intelligence (AI), can assist in this process. It demonstrates how AI can predict threats based on the analysis of large volumes of data, automate alert systems, optimize evacuation routes in real time, automatically assess damage, support decision-making in crisis situations, and provide psychological support to personnel. A conceptual model of such an integrated occupational safety and civil defense system, enhanced by AI tools, is proposed. This allows for a shift from a simple reaction to events towards proactive, preventive safety management. Finally, practical and scalable recommendations are formulated for enterprise managers to help them incrementally implement technological innovations into safety processes to increase the resilience and protection of personnel in wartime conditions, even with limited resources.
Copyright (c) 2025 Volodymyr Pogrebnyak, Oleksandr Kondrat, Iryna Perkun, Andrii Pogrebnyak https://creativecommons.org/licenses/by-nc-sa/4.0
Experimental studies of the strength of masonry under axial and local compression
Masonry is one of the traditional building materials that remains highly relevant in modern civil and industrial construction. Determining its strength characteristics, especially under compressive loads, remains an important scientific and technical task, since such forces prevail in load-bearing walls, columns, and other structural elements of masonry. The compressive strength of masonry is affected by numerous factors, including the strength and geometric properties of the units, their shape accuracy, the presence of voids, the mortar strength, the deformation characteristics of hardened mortar, the workability of the mortar mix, the bond strength between mortar and masonry units, the degree of joint filling, the bonding pattern, and the overall quality of workmanship. When determining the strength of masonry under local compression, the nature of the sample's destruction is taken into account, on the basis of which a corresponding kinematic scheme is developed that determines the main parameters that affect the strength of the masonry. One of the key issues is the lack of a unified approach to determining the geometric parameters of the samples used for testing. The objective of this study is: 1. to develop scientifically based recommendations for the optimal shape and size of standard samples that allow the most reliable assessment of the axial compressive strength of masonry based on test results; 2. to consider the case of local compression of walls by stamps located near the end face with a width less than the wall thickness.
Copyright (c) 2025 Maryna Pents, Oksana Dovzhenko https://creativecommons.org/licenses/by-nc-sa/4.0
Structural Features and Survey Results of the 18th-Century Illinska Church in Korop
The article presents the results of a comprehensive study of the 18th-century Illinska Church located in the urban-type settlement of Korop, Chernihiv region, which is a valuable monument of Ukrainian Baroque architecture. The aim of the study was to identify the structural characteristics of the building and to determine the technical condition of its main elements. The research utilized archival materials that made it possible to reconstruct the history of construction and subsequent renovations, as well as data from on-site surveys conducted by the author during field expeditions.The main attention was focused on the analysis of the masonry walls, the wooden floor structure, and the metal tie rods that ensure the spatial rigidity of the building. It was established that the masonry consists of brick laid on a lime mortar and contains areas of material loss and wall cracking. The walls in the northern part of the church are 2 m thick, while those in the southern part are 1 m thick. The wooden structural elements of the floor are almost completely destroyed, with remaining fragments in an emergency condition. The metal tie rods embedded in the masonry are partly cut and are made of square steel bars with a cross-section of 4×4.5 cm, as well as steel strips measuring 7–8×1.0–1.5 cm. The study was carried out with the support of the Department of Urban Planning and Architecture of the Chernihiv Regional State Administration. The obtained results have practical significance for the further development of conservation and restoration guidelines for the church and are of scholarly interest in the context of studying traditional structural systems and their adaptation to modern operating conditions.
Copyright (c) 2025 Mykola Korzachenko https://creativecommons.org/licenses/by-nc-sa/4.0
Defensive Urbanism in Modern Conflicts: The Case of Ukraine
This paper examines the influence of dense urban development on modern military conflicts, with a focus on Ukraine. The research highlights how urban form dictates the dynamics of combat operations, restricts troop mobility, and shapes tactical decisions. Historical models of fortified cities are considered, as well as contemporary examples, including Israel’s urban planning paradigm. The paper argues that Ukraine must adapt its state-building standards to incorporate defensive urbanism and resilient infrastructure. Recommendations for integrating urban planning with defense strategies are provided.
Copyright (c) 2025 Bohdana Rudakova, Ruslana Tryhub https://creativecommons.org/licenses/by-nc-sa/4.0
Results of the Inspection and Technical Condition Assessment of the Multi-level Load-Bearing Roof Structures of a Supermarket before the Installation of a RoofTop Solar Power Plant
A comprehensive detailed inspection and technical condition assessment of the multi-level load-bearing roof structures of a supermarket was conducted to determine the feasibility of installing photovoltaic elements on the building's roof. The work included analysis of technical documentation, visual and instrumental inspection of the building structures, and verification calculations. During the visual inspection, the structural features of the building and the technical condition categories of the building structures based on characteristic signs were established. During the instrumental inspection, non-destructive testing methods were used to determine the concrete strength and reinforcement parameters for reinforced concrete structures, and the steel strength and element thicknesses for the roof beam elements. Verification calculations established the load-bearing capacity of the reinforced concrete slab and metal roof beams. In the event of installing a rooftop solar power plant, a limitation on the building's service life was recommended. The research carried out underscores the necessity of conducting building and structure inspections when installing rooftop solar power plants.
Copyright (c) 2025 Ivan Matiushenko, Ruslan Kozak, Serhiy Gayda, Roman Shchupakivskyy, Zoya Kopynets https://creativecommons.org/licenses/by-nc-sa/4.0
Results of the Study of Mining and Processing Plant Waste for the Construction of Motor Roads and Railway Tracks
The pavement of technological motor roads consists of rock formations extracted from the quarry. With the current increase in the tonnage of quarry transport, the road pavement structure is also changing. On the other hand, the construction of the railway subgrade on dumps and stripping horizons of the quarry leads to increased operating costs for track repair and maintenance works. The relevant task is to investigate the physical and mechanical properties of rock materials from PJSC “Inhulets Mining and Processing Plant” (InGZK), to develop optimization measures and recommendations for the efficient use of these rocks for technological road pavements and the construction of railway embankments within the quarry and waste dumps of PJSC “InGZK”. The aim of this paper is to study the physical and mechanical properties of the rock formations of PJSC “InGZK” and to determine the grain-size composition of crushed stone produced from dense hard rocks. To determine the physical and mechanical properties of the rock materials of PJSC “InGZK,” the following were sampled: iron ore rock (migmatite) and associated dense rock types such as amphibolites, schists, granites, substandard quartzites, oxidized quartzites, oxidized jaspilites, and arkosic metasandstones. Experimental studies provided the physical and mechanical parameters and data on the grain-size composition of crushed stone from these rocks. Examination of the structure of amphibolites and schists from PJSC “InGZK” showed that these rocks have a dense texture, which provides high strength (1000 and 1200), and their mineral inclusions do not require additional beneficiation. The grains of crushed stone obtained from amphibolites and schists of PJSC “InGZK” have a cubical shape and high void content. This opens up the possibility of their use in the construction of roads and railway tracks, as well as in concrete and reinforced-concrete structures.
Copyright (c) 2025 Oleksandr Valovoi, Dmytro Brovko, Vitalii Afanasiev, Maksym Valovoi, Dmytro Popruha https://creativecommons.org/licenses/by-nc-sa/4.0
Cement-ash compositions with ash - fluidized bead removal
The results of studies of ash-fluidized bed removal by X-ray structural analysis, differential thermal analysis and IR spectrometry are presented. Ashes and ash-slags of the fluidized bed have slightly different properties due to the fact that in fluidized bed boilers the fuel is burned for several seconds longer than in traditional boilers. During this time, the dispersed part of the mineral component of the fuel has time to melt and transform into a glass phase, as a result of which their internal energy increases and they become capable of chemical reactions. The results of the research allowed us to establish that the fly ash of anthracene coal from domestic deposits when burned in a fluidized bed can be classified as medium-calcium and sulfate, which may hide the manifestation of hydration properties. The results of the IR spectrometry study confirmed the presence of calcium sulfate compounds of the gypsum and anhydride type in the fly ash composition. Sulfate minerals in the presence of aluminates and moisture can contribute to the formation of the ettringite mineral during the hardening of cement-ash compositions, which can contribute to the emergence of expansion stresses in cement stone. However, the study of cement-ash stone by X-ray structural analysis methods at the age of six months does not confirm the formation of ettringite. Testing of cement-ash compositions showed that the strength of the compositions at the vintage age is somewhat lower than that of cement stone. However, with a further increase in the hardening period, the rate of strength gain of the compositions is somewhat greater than that of cement stone.
Copyright (c) 2025 Rasul Akhmednabiev, Andrii Yalovehin https://creativecommons.org/licenses/by-nc-sa/4.0
Calculation of steel-reinforced concrete structures made of cold-formed steel profiles under biaxial loading
The aim of the work is to establish theoretical dependences for determining stresses at the extreme points of the cross-section of steel-reinforced concrete rod structures made of cold-formed steel profiles under biaxial bending loading. The steel part of the cross-section of the rod under consideration is a U-shaped profile, which is filled with concrete. At the first stage of manufacturing a prestressed rod, an initial bending of the steel part of the beams opposite to the operational one is created using mechanical jacks. During concreting of the U-shaped cavity and for the period of setting of the concrete to the design strength, the jacks under the steel beams remain. At the live load (third stage), the combined steel-concrete cross-section works together. In the concrete part, deformations develop from the undeformed (zero) state, while in the steel part, deformations of the normal cross-section are superimposed on the already existing deformations opposite to the operational ones obtained at the first stage of the combined structure during its manufacture.
Copyright (c) 2025 Oleksandr Drobotia, Hennadii Vakhnenko https://creativecommons.org/licenses/by-nc-sa/4.0
Restoration measures for foundations of metal silos on degraded loess soils
This paper examines the restoration of the serviceability of foundations of steel silos located on wetted and degraded loess soils. Based on the survey results and the analysis of the recorded deformations, a sequence of engineering measures is presented, including local repair of the ring foundation, restoration of the underground gallery, strengthening of the anchor connections and replacement of the pavement. It is shown that the applied set of repair measures ensures the stabilisation of the foundation structures and allows continued operation of the silos without a complete shutdown. The effectiveness of the implemented measures is confirmed by the results of geotechnical and geodetic monitoring conducted after the completion of the repair works.
Copyright (c) 2025 Oleksii Kichasov https://creativecommons.org/licenses/by-nc-sa/4.0
Flexural Behaviour of 3DCP Beams with Expanded Metal Sheet Reinforcement: Experimental Investigation and Numerical Verification
An experimental and numerical study of the flexural behavior of 3D-printed concrete (3DCP) beams reinforced with expanded metal sheet are presented in this paper. Four-point bending tests on beams of 3DCP were carried out in accordance with DSTU B V.2.7-214:2009, recording load–deflection curves and strains. The 3DCP showed an equivalent axial tensile strength 30–45 % lower than that of class C16/20 concrete. Correctly oriented sheet reinforcement increased failure load and flexural toughness by about 30–40 %, while a 3D FE model in LIRA-FEM reproduced ultimate loads within 5–10 % but underestimated stiffness.
Copyright (c) 2025 Petro Reznik , Dmytro Petrenko, Anton Volodymyrov, Dzhamaldii Alataiev https://creativecommons.org/licenses/by-nc-sa/4.0
Conditioning of boron-containing LRW with composite binders
Modern management of liquid radioactive waste (LRW) requires mandatory conditioning, which they practically carried out by cementing, most often with Portland cement. As an alternative to cementing, alkaline binders are used, which are chemically more stable, increase strength over time, and do not pollute the atmosphere with CO2. Most often, the basis of such binders is granulated blast furnace slag in combination with alkaline substances. As a development of LRW management, the direction of conditioning with composite binders we formed, which combines Portland cement and blast furnace slag in composition. Composite binders can take into account the positive properties inherent in the constituent components, while the properties will depend both on the physicochemical parameters and on the conditions under which the LRW is conditioned. The work shows that boron-containing LRWs with a pH > 12 and a total salt content of 60.2% can be conditioned with composite binders, with a ratio of granulated blast-furnace ground slag (particle size < 80 μm): PC-500 cement as 1:1 with a compressive strength > 3 MPa at a temperature of 55 - 60C. The amount of LRW (imitate) in the compound can be 35 - 40%. Alkaline substances included in the LRW composition they used as a binder hardening activator, without the addition of additional alkalis and liquid glass. Depending on the types of components involved: Portland cement, blast-furnace slag or composite binder, samples of compounds with a compressive strength of mainly > 10.3 MPa we obtained.
Copyright (c) 2025 Alla Rozko, Yuriy Fedorenko, Sergii Guzii https://creativecommons.org/licenses/by-nc-sa/4.0
Machine Diagnostics in Mechatronic Systems: Analysis Methods and Intelligent Technologies
The article examines modern approaches to machine diagnostics within mechatronic systems using signal processing methods and intelligent machine learning technologies. The structure of mechatronic complexes is analyzed, and their specific features that influence the development of diagnostic models are identified, including the high level of interdependence between mechanical, electronic, and software components. The feasibility of applying hybrid diagnostic systems is substantiated, where convolutional neural networks (CNN) are employed for automatic extraction of informative features from vibration and sensor data, while recurrent networks such as LSTM provide analysis of the temporal dynamics of processes and prediction of degradation states. A generalized theoretical diagnostic model is proposed, combining spectral methods of preliminary signal processing, multisensor data integration, and modules for technical condition prediction. The obtained results demonstrate the high effectiveness of intelligent algorithms in detecting early signs of faults, even under noise disturbances and varying operating modes. The proposed approach can be applied in maintenance systems at industrial enterprises to enhance the reliability and extend the service life of mechatronic systems.
Copyright (c) 2025 Serhii Oryschenko, Viktor Oryscshenko https://creativecommons.org/licenses/by-nc-sa/4.0
Green Construction: Innovations, Energy Efficiency, and Prospects for Ukraine
This article explores the concept of green construction as a pioneering approach in contemporary construction, aiming to minimize environmental impact and enhance energy efficiency. Modern approaches to resource use, the implementation of energy-saving technologies, and ecological materials are analyzed. International experience and certification systems, such as LEED, BREEAM, DGNB, and WELL, are reviewed with emphasis on practical application. Special attention is paid to the prospects for green technologies in Ukraine during post-war reconstruction, the formation of sustainable urban ecosystems, and integration into the European space [2–8].
Copyright (c) 2025 Iryna Rutkovska, Roman Salabai, Iryna Salabai https://creativecommons.org/licenses/by-nc-sa/4.0
Strain Energy Density-Based Topology Optimization Using SIMP and Local Failure Criteria for 3D-Printed Concrete Structures
This paper presents a strain energy density–based topology optimization method tailored for brittle materials such as 3D-printed concrete. Extending the SIMP framework, the approach incorporates a local failure criterion derived from a Lode–Nadai ultimate strain energy model, allowing each element to adapt to tension-, compression-, or shear-dominated stress states. A memory-locking mechanism preserves elements that exceed their local energy limits, preventing unstable material removal and improving structural robustness. The method is implemented in the FEniCS finite element environment, enabling full customization of material behavior and numerical routines. Benchmark simulations of a slab, cantilever beam, and foundation block demonstrate that the proposed strategy generates manufacturable, failure-resistant layouts and produces more physically consistent topologies than traditional compliance-based designs, particularly for materials with limited tensile capacity.
Copyright (c) 2025 Oleg Kalmykov, Ivan Demianenko, Sergei Potapov, Dzhmaldii Alataev https://creativecommons.org/licenses/by-nc-sa/4.0
Study of factors affecting the energy consumption of the mixing plant for the preparation of aerated concrete
The current stage of development of the construction industry is characterized by increased requirements for the energy efficiency of technological processes and the quality of building materials. The preparation of aerated concrete is a complex technological process and its efficiency is largely determined by the mixer’s operating parameters. One of the key indicators that affects both the quality of the finished mixture and the cost-effectiveness of the process is the energy consumption of the mixing plant. The article presents the results of a study of the influence of the main technological and design parameters on the energy consumption of the mixing plant for preparing aerated concrete. The purpose of these measurements was to determine the patterns of changes in the mixer's electricity consumption depending on the frequency of rotation of the working body, the duration of mixing and the mobility of the concrete mixture. To achieve this goal, mathematical planning methods were used, namely a three-factor experiment of the second order, thanks to which a mathematical model of the electricity consumption of the plant for preparing aerated concrete was obtained in the form of a regression equation. The developed model allows us to estimate the magnitude of the individual impact of each factor on energy consumption and determine their optimal range. Based on the data, graphical dependencies were constructed that reflect the change in the energy consumption of the plant. The results of the study show that the decisive influence on the energy efficiency of the process is the frequency of rotation of the working body and the fluidity of the mixture, while the rational duration of mixing is about 40 seconds. The study creates the prerequisites for optimizing the energy consumption of mixing equipment and improving the quality of the preparation of aerated concrete in mobile forced-action plants.
Copyright (c) 2025 Oleksii Vasiliev, Volodymyr Kulai https://creativecommons.org/licenses/by-nc-sa/4.0
Analysis of the Possibility of Adapting Basement Premises in Multi-Story Buildings as Civil Protection Shelters
The article examines the possibility of adapting basement premises in multi-story buildings in light of state building code requirements. Based on drawings, the author conducted an analysis of key structural parameters such as entrance width, ceiling height, area, and their compliance with regulatory requirements. The study aims to evaluate the effectiveness of using basement premises as shelters in the context of modern civil protection challenges. The analysis results can be used to improve regulatory documentation and adapt existing basement premises for civil protection needs.
Copyright (c) 2025 Ihor Yurchenko https://creativecommons.org/licenses/by-nc-sa/4.0
Determination of the Main Performance Indicators of a Forced-Action Concrete Mixer Using Similarity Criteria
The study focuses on the improvement of a forced-action concrete mixer designed for the preparation of low-workability concrete mixtures. The methodology is based on the application of dimensionless similarity criteria and mathematical modeling. Analytical dependencies for calculating the output rate and drive power were derived based on the geometric and kinematic parameters of the mixer, considering the dynamics of multi-loop mixing. The obtained results enable model scaling without the need for full-scale testing. Further research is planned to optimize operational modes for continuous mixing machines
Copyright (c) 2024 Vladimir Blazko, Anna Anishchenko, Stanislav Kostenko, Volodymyr Gerasymenko https://creativecommons.org/licenses/by-nc-nd/4.0
Development of an energy-saving design for the feeding system of a concrete mixing plant
The study focuses on the development of an energy-saving design for concrete mixer mix components supply system to enhance efficiency and reduce environmental impact. The proposed changes to the schematic diagram include the implementation of separate hoppers with individual conveyors to optimize energy consumption and increase productivity. These modifications aim to improve energy efficiency, reduce material change time, and prevent congestion in the supply system, ultimately leading to enhanced productivity and streamlined production processes. This study highlights the importance of innovative design solutions in the feeding supply system of industrial plants to drive sustainability and efficiency improvements.
concrete mixer mix components supply system
Copyright (c) 2023 Bogdan Korobko, Oleksandr Levchenko, Rostyslav Rudyk http://creativecommons.org/licenses/by-nc-sa/4.0
Approbation of the express penetration method for assessing the strength of sedimentary cohesive rocks
The advantages of express methods of penetration and probing for evaluating the mechanical parameters of cohesive sedimentary rocks over traditional methods of testing them in single-plane displacement devices, odometers, and stabilometers are analyzed, such as: complete independence from the applied force and cone immersion depth; simplicity and reliability of the equipment; high reliability of results, etc. The methodology and results of 185 sets of penetration-shear tests of various clay rocks, from sandy loams to clays, are presented. Their results were used to determine the strength indicators of cohesive rocks (angle of internal friction and specific adhesion). Through statistical processing of experimental data, it was confirmed that for the water-saturated state of clay rocks there is an almost functional relationship between the penetration index and the porosity coefficient.
Copyright (c) 2023 Yuriy Vynnykov, Andrii Bondar, Anna Liashenko, Valeriy Novokhatniy, Мaryna Rybalko https://creativecommons.org/licenses/by-nc-nd/4.0
Consideration of the structures working conditions in the method of limit states
In the method of limit states, the coefficient of working conditions must take into account all the features of the work and operation of structures. In the code editions, the scale of these coefficients was regularly reviewed and supplemented. Probabilistic aspects of substantiating the coefficients of the working conditions were developed by researchers of the building structure’s reliability. The interpretation of the constructive correction as an experimental analog of the coefficient of working conditions was achieved by full-scale tests of industrial buildings structures. The analysis of the reliability of compressed-bent elements and statically uncertain systems determined the additional coefficients of the working conditions. The article contains a systematic analytical review of normative documents and scientific publications with an analysis of the evolution of steel structure design codes in terms of changes in the coefficient of working conditions and the involvement of research, experimental and statistical data.
Copyright (c) 2023 Sergii Pichugin https://creativecommons.org/licenses/by-nc-nd/4.0
The limit state of steel beams research of damaged building elements
The article is devoted to the study of the limit state of steel І-beams under buckling with operational geometric imperfections revealed during inspections of damaged elements of reconstructed buildings. The influence of damage in the form of initial curvature in the horizontal plane on the stability and bearing capacity of structures is analyzed. The possibility of using bearing capacity resources, namely lateral bracing restraint with the help of structures attached to a steel beam, is considered. The proposed approaches are aimed at optimizing the use of materials and increasing savings by detailing the verification calculations of damaged steel beams.
Copyright (c) 2023 Serhii Hudz, Vitaliia Harkusha, Yuriy Sergienko, Tetiana Hodun https://creativecommons.org/licenses/by-nc-nd/4.0
The mobile communication antenna structures classification
The article analyses the problem of mobile communication antenna structures classification, considers their main design features, advantages and disadvantages. Generalized classification of mobile communication antenna structures operated in Ukraine is proposed. The regular recurrence of accidents and destruction of antenna structures indicate that the existing methods of calculation and design of such structures do not always take into account all their structural features. Technical and constructive solutions, peculiarities of operation of structures under load, aspects of application and their requirements for safe operation are considered, strengths and weaknesses of each type of antenna structures are given. One of the most effective and widely used antenna structures are lattice towers and masts. The main advantage of lattice towers is a small building area, however, from the point of view of consumption, steel masts are more cost-effective with the same height of the structure and payload. However, the cost of building an antenna structure is not always the main criterion for choosing its design scheme. First of all, radio-technical, technological and architectural requirements are of great importance. In the absence of restrictions on geometric parameters, preference is given to towers with a minimum number of faces, for example, when going from a 3-faceted to a 4-faceted tower, its weight increases by 10%. For technical and economic efficiency, not only rational types of cross-sections of elements are selected, but also various combined structural systems are developed. A good example is introduction into mass construction of combined supports on the basis of a conical concrete monopole CK-26, on top of which a steel lattice extension is installed. The structural disadvantage of the combined supports based on the conical concrete monopole CK-26 is their limited bearing capacity at the +2,000...+3,000 m mark, which in a number of cases led to accidental destruction in this particular area.
Copyright (c) 2023 Anton Hasenko, Yurii Padun, Mykola Bibik https://creativecommons.org/licenses/by-nc-nd/4.0
Analysis of equipment for thermoplastic molding artificial products of spatial form
The study explores the innovative use of recycled plastic in brick production in the construction industry in Ukraine. It examines the production process, including the collection and processing of plastic waste, and the formation of bricks using methods such as plastic molding and semi-dry pressing. The research emphasizes the importance of pressure distribution in screw presses for the compaction of clay in construction ceramics production and highlights the significance of vacuuming the molding mass for improving the quality of molded products. Plastic-brick products are found to offer advantages such as altered strength, improved insulation properties, and lighter weight. Comparing technological schemes, the semi-dry method of brick production is noted to have higher metal capacity and lower labor intensity compared to the plastic method. The study aims to enhance the efficiency and results of thermoplastic molding in the construction industry, contributing to sustainable construction practices and reducing environmental impact.
Copyright (c) 2023 Ivan Suchkov, Rostyslav Rudyk https://creativecommons.org/licenses/by-nc-nd/4.0
Сalculation of optimal parameters for a vibratory finishing machine for decorative elements with an active working tool
The calculation of optimal parameters for a new design vibration installation with an active working body is proposed using numerical methods. By modeling the system as a mass-spring-damper system and applying harmonic Fourier analysis of the vibrations, a mathematical model of the dynamic interaction between the working body and the part was obtained, taking into account additional friction forces, the angle of inclination, and elastic and damping forces. The key determined parameters—phase shift between the vibrations of the working body, the part, and the abrasive. An example of calculating optimal parameters using the gradient descent method is provided. Based on the calculation results, comparative time graphs of the phase shift of vibrations of the part and the working body, as well as amplitude, were constructed.
mathematical model of dynamic interaction between the working tool and workpiece in a vibratory machine
phase shift of vibrations of the working tool and workpiece
Copyright (c) 2023 Dmytro Bugrov, Tetiana Buhrova https://creativecommons.org/licenses/by-nc-nd/4.0
Justification for the Choice of a Modeling Scheme for the Hydrocarbon Preparation Process for Transportation Using Supersonic Separation
A study was conducted to select a modeling scheme for the process of preparing hydrocarbons for transportation by supersonic separation. Modeling was performed in the HYSYS environment, which allowed obtaining optimal parameters for effective removal of moisture and heavy hydrocarbons. The influence of pressure and temperature changes on the efficiency of heavy hydrocarbon extraction was analyzed. The most effective modeling scheme was selected, which provides high prediction accuracy. The results obtained can be used for further optimization of gas purification technological processes and their adaptation to industrial applications.
Copyright (c) 2023 Tetiana Nesterenko , Mykola Nesterenko, Oleksandr Shevchenko, Oleksii Omelchenko https://creativecommons.org/licenses/by-nc-nd/4.0
Improvement of the industrial extraction method of methane homologues
Absorption processes are one of the main ones in the preparation of hydrocarbon gases. However, in connection with a decrease in the pressure of the input gas, a number of facilities for the preparation of industrial products cannot provide the necessary technological regime and therefore require reconstruction. A typical example is the installation of low-temperature absorption at the main facilities «Solokha» of the gas industry management «Poltavagasvydobuvannya» where there is a decrease in the efficiency of the separation process of natural and oil gases. According to the results of analytical studies, to eliminate the indicated shortcoming, a variant of the reconstruction of the ULTA MF «Solokha» is proposed, which involves the use of a scheme with preliminary saturation of the regenerated absorbent. This will increase the extraction rate of components by 21.96%.
Copyright (c) 2023 Mykhailo Pedchenko, Larysa Pedchenko, Nazar Pedchenko, Vasyl Savyk https://creativecommons.org/licenses/by-nc-nd/4.0