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»
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
The article presents a comprehensive analysis of load applicator designs used in the compaction technologies of stiff and lightweight concrete mixtures. The role of loading is revealed as one of the key factors influencing the effectiveness of forming products made from concrete with a low water-to-cement ratio. The main operating principles of load applicators are described, which apply additional force to the concrete mixture in combination with vibrational loading. A classification of load applicators is provided based on design features and energy source: inertial, non-inertial, pneumatic, and vibratory load applicators. Special attention is given to combined devices that integrate vibrational and impulse action on concrete. The study summarizes research findings that confirm the advantages of combined compaction, particularly when using pneumatic load applicators with adjustable pressure. It has been established that the use of active load applicators allows for a reduction in cement consumption by up to 30%, a decrease in product forming time by up to 50%, improved compaction uniformity along the height, and enhanced surface quality. An original design of an active load applicator with a vibration exciter and impact elements is proposed, providing impulse compaction with adjustable pressure and frequency. The main unresolved aspects of the problem are identified — the lack of unified methodologies for calculating loading parameters, insufficient adaptability of designs to changes in product geometry and concrete mixture properties. The feasibility of developing intelligent controlled load applicators capable of adapting to forming conditions is substantiated to improve the efficiency of reinforced concrete product manufacturing.
Copyright (c) 2023 Mykola Nesterenko, Olexandr Panfilov, Maxim Pyrlyk https://creativecommons.org/licenses/by-nc-nd/4.0
Studies of multilayer bent reinforced concrete structures of rectangular cross section review
Reducing the use of cement and reducing the weight of concrete in bending reinforced concrete elements is an important task in modern construction. To solve this problem, various methods are being implemented, including the use of both removable and non-removable void formers, and the combination of several materials (e.g., heavy in the compressed zone and light in the tensile zone of concrete) for their mutually beneficial joint operation. The paper provides an overview of several experimental and theoretical studies in these areas, which substantiate the possibility and feasibility of reducing the strength of concrete in the tensile zone of bending reinforced concrete structures, and as a result, reducing the consumption of cement for the preparation of concrete mix for structures, without prestressing the latter. The use of two- and multi-layer elements reduces the dead weight of structures, improves sound and thermal insulation properties, which leads to savings in materials, labor and financial resources. The right choice of material for each layer allows for the creation of structures with high performance characteristics.
Copyright (c) 2023 Романенко Д.Б. https://creativecommons.org/licenses/by-nc-nd/4.0
Sorting lines as an element of household waste management at the regional level
The article identifies the problems of household waste recycling, summarizes the data on the planned waste management infrastructure facilities, and substantiates the feasibility of building waste treatment facilities in Poltava region. The absence of a recycling system (including a separate collection system) for household waste results in Ukraine losing millions of tons of resource materials contained in waste that could potentially be put back into economic circulation. It has been established that sorting mixed household waste will enable its further reuse and recovery and reduce the load on landfills. It is determined that the stage of sorting (separation) of household waste is an integral part of integrated waste management solutions and, accordingly, is a mandatory stage before further application of waste treatment technologies
Copyright (c) 2024 Yurii Holik, Oksana Illiash, Tetiana Serha, Iuliia Chepurko http://creativecommons.org/licenses/by-nc-sa/4.0
Elucidation of the technological conditions for the formation of alkali silicates heat-insulating products based on ash-removal of thermal power plants and liquid glass
The carried out complex study gives a reliable idea of the trends in the joint behavior of structural components in water-salt systems of nitrate precursors of neodymium, cesium, strontium in the preparatory stages of technological regulations for both concentration and immobilization of liquid radioactive waste of the nuclear energy industrial complex 137Cs, 90Sr and thermal activation. The stages of such transformations have been revealed; the patterns of complex and phase formation in systems and the factors influencing them have been clarified. It has been studied a number of physicochemical properties of the resulting intermediate phases (coordination neodymium nitrates: their composition, types of compounds, atomic crystal structure, shapes of Ln coordination polyhedra, types of ligand coordination, features and patterns of behavior in heat treatment processes. It has been established that, under the conditions of the existence of solutions, the system CsNO3 – Nd(NO3)3 – H2O is characterized by the formation of 2 anionic complex compounds Ln3+, the system Sr(NO3)2 – Nd(NO3)3 – H2O – is of the eutonic type. The ongoing competing reactions are a powerful technological factor that has a significant impact on changes in the activity of structural forms of Ln3+. Systematized information enables to elucidate the mechanisms and kinetics of transformations of structural components in similar objects. Also, it enables to transfer the resulting system of knowledge to the promising technological solutions for the solidification of liquid radioactive wastes
Copyright (c) 2024 Оleksandr Dryuchko, Natalia Bunyakina, Оleksandr Shefer, Ruslan Zakharchenko, Dmytro Kyslytsia, Marina Moskalenko https://creativecommons.org/licenses/by-nc-nd/4.0
Experimental and theoretical studies of reinforced concrete structures using fine aggregates from iron ore beneficiation waste
Beneficiation waste from mining and processing plants possesses the characteristics of strong and inexpensive aggregates suitable for structural reinforced concrete. This enables the practical use of such waste in the production of precast reinforced concrete. Practice has demonstrated the feasibility of using iron ore beneficiation waste as fine aggregate in concrete. The authors conducted studies on the behavior of concrete structures incorporating fine aggregates derived from iron ore beneficiation waste. This article presents the results of research on concrete, elements, and structures with fine aggregates from iron ore beneficiation waste under low-cycle loading.
Copyright (c) 2024 Oleksandr Valovoi, Dmytro Brovko, Maksym Valovoi, Dmytro Popruha, Alexander Eremenko https://creativecommons.org/licenses/by-nc-nd/4.0
The raw material mixture from the silicon-like techno genic component the ash-removal of thermal power plants and the preparation methods of waterproof porous heat-insulated materials wide usage for raw mass hot foaming powdered two-stage technology are developed. The development uses the polyfunctional properties of liquid glass as a) the binder component; c) breeder; c) the speed regulator of the clamping mass hardening. Its optimized version begins to solidify at its usual temperature from the moment its "reproduction" is soluble glass and forms a paste-shaped cake with a set of properties necessary for the next fragmentation. The proposed formulation allows compositions processing in various ways, with the formation of granular heat-insulating fillers, materials for thermal insulation in complex structures, slab and shell-like types of thermal insulation materials. The task is set, depending on the goals and features of the tasks being solved; it is possible to conduct several different methods at the final stages of their obtaining. Two stages of the recycling process determine the character and behavior of the rare-glass composite systems constituent components during heat treatment, their strong adhesion to most structural materials and the need to solve billets easy removal problem from the molding unit. Study results can be used in the field of building materials production, in particular porous artificial products, in obtaining granular insulating material and light aggregate for concrete industrial and civil construction, in thermal engineering as thermal insulation, etc.
alkaline-silicate heat-insulation composite materials
Copyright (c) 2024 Оleksandr Dryuchko, Natalia Bunyakina, Vasyl Halai, Bohdan Boriak, Andrii Tretiak, Dmytro Kyslytsia https://creativecommons.org/licenses/by-nc-nd/4.0
Computer modelling of the flow structure in a combined mixer for aqueous suspensions with solid and gas phases
Computer modeling of multiphase flows in mixers for aqueous suspensions with solid and gas phases opens up new opportunities for optimizing mixing processes in industry. The creation of CFD-DEM models allows taking into account the interaction of liquid, solid and gas phases, fixing the features of circulation, mass transfer and rheological behavior of the medium. The article considers the features of the formation of the flow structure in a combined-type mixing chamber, analyzes the nature of changes in turbulent and convective processes in the presence of a gas phase and solid inclusions, and also substantiates approaches to building effective mixing modes.
Copyright (c) 2024 Ruslan Toister, Anton Khrapach https://creativecommons.org/licenses/by-nc-nd/4.0
Calculation of structural parameters of a vibratory machine
The article is dedicated to the development of a vibratory machine for compacting concrete mixtures, ensuring the adaptation of vibration modes to the mixture's condition to enhance energy efficiency and concrete quality. The study was conducted through literature analysis, vibration parameter modeling, and calculation of structural characteristics. It was established that modern methods, such as DEM and CFD, highlight the need for flexible vibration control to prevent microstructure defects. A machine design based on elastic pneumatic shells operating in resonant mode is proposed. Key formulas for calculating the vibratory platform are provided. The design achieves a 15% reduction in energy consumption compared to traditional machines, stable compaction, and adaptability to various mixture types. The results confirm the effectiveness of the proposed solution for forming a dense concrete microstructure. Further research involves experimental validation and parameter optimization.
Copyright (c) 2024 Volodymyr Gerasymenko, Olena Protsenko, Volodymyr Lus, Iryna Bielykh https://creativecommons.org/licenses/by-nc-nd/4.0
Investigation of the dependence of the amplitude of vertical vibration displacements of the working element of a vibrating platform on its inertial and stiffness parameters using a three-factor experiment
During preliminary experimental studies, it was established that the amplitude of vibration displacements of the moving frame points of the vibration platform is most significantly influenced by such characteristics as the stiffness of vibration-isolating supports, the distance from the centre of oscillation, and the mass of the moving part. These factors were selected as independent factors in the research using a three-factor experiment. As a result of mathematical and statistical processing of the experimental data, a second-order multiple regression equation was obtained. The calculated values of the variance at the zero point, the variance of adequacy, and Fisher's criterion confirm the possibility of using the obtained equation to describe the studied process. Based on the research results, three three-dimensional response surfaces were constructed, describing the dependence of the amplitude of vibration displacements of selected points on the surface of the working body of the vibration platform on two variable input factors at a fixed value of the third factor at the base level. The results obtained allow for optimal regulation of vibration-isolating supports with variable stiffness, which, in turn, allows for improving the quality of concrete product compaction.
Copyright (c) 2024 Oleksandr Orysenko, Oleksandr Sheka https://creativecommons.org/licenses/by-nc-nd/4.0
Investigation of the thermal and moisture regime of cold attics using an instrumental method
The article presents the results of an experimental study of the thermal and humidity regime of a cold attic using modern measuring instruments. The relevance of studying the microclimatic parameters of the attic space is substantiated in view of their critical role in ensuring the durability and safe operation of buildings. The dynamics of temperature and humidity changes in a cold attic in different periods of time is analyzed. Based on the results of the study, practical recommendations for optimizing the microclimate in the attic space aimed at preventing the formation of condensation, mold, and structural deformations are formulated.
Copyright (c) 2024 Olena Filonenko, Maksym Filipets, Denys Berun https://creativecommons.org/licenses/by-nc-nd/4.0
Precast flat plate frame of buildings for renewal of the housing stock of Ukraine
The suggested precast flat slab system is composed of columns and flat plates that connect to the columns without the use of consoles or capitals. This structural system is intentionally designed in such a way that lines of arrangement of plastic hinges between precast plates are artificially created. Consequently, an analysis of precast flat plate floor systems is proposed based on the yield line method. The utilization of the yield line method facilitates the development of straightforward engineering design schemes, potential fracture scenarios, and the determination of the load at which destructive failure occurs for all types of precast flat plates. By employing the yield line method within the ultimate equilibrium state, utilizing a nonlinear deformation model with an extreme criterion, design equations to address the bearing capacity of flat plate of the frame structural system are derived. These formulas are well-suited for practical engineering use and account for the plate's installation conditions as part of a precast flat floor.
Copyright (c) 2024 Andriy Pavlikov, Olha Harkava https://creativecommons.org/licenses/by-nc-nd/4.0
Review of multilayer reinforced concrete beams with rectangular cross section experimental-theoretical studies
One of the options for reducing cement consumption for the preparation of concrete for bent reinforced concrete structures is the use of two-layer beams with higher strength concrete in the compressed zone and lower strength concrete in the tensile zone, which saves cement without losing structural strength. Experimental tests and theoretical calculations of concrete deformations in the compressed zone of five series of concrete beams with cross-sectional dimensions of b×h = 100×160 mm and a total length of 1500 mm were compared; compressed zone concrete of class C20/25; tensile zone concrete of class C12/15; reinforcement in the tensile zone - 2Ø12 mm of class A400C. The beams differed in the thickness of the concrete layers in the compressed and tensile zones. As a result of the comparison, it was found that the average value of the ratio of theoretical to experimental results was 15.1%; the mathematical expectation of this ratio was 0.856; the coefficient of variation of the ratio was 9.3%, which indicates a fairly high correlation of results.
Copyright (c) 2024 Dmitrij Romanenko, Oleksandr Krupchenko, Pavlo Yurko https://creativecommons.org/licenses/by-nc-nd/4.0
Technological equipment package for preparing polystyrene concrete mixture
The study of the production process for polystyrene concrete mixture products is driven by the need to ensure high material quality while meeting modern construction standards. To achieve this goal, an analytical method was used for reviewing literature sources, along with a design-calculation approach in the development of a new type of equipment. The main findings highlight the shortcomings of conventional concrete mixers, including extended mixing time, mixture non-uniformity, and material sticking to working surfaces. A novel design of a gravity-compelled cascade-type concrete mixer is proposed, featuring a horizontal ribbon-paddle shaft and a rotating drum. A key innovation is the ability to adjust the rotation modes depending on the mixture composition and the presence of sand. A compact equipment package was developed, comprising a mixer, fiber cutter, belt and screw feeders, all mounted on a single frame. The use of a belt feeder with synchronized component feeding and an automated fiber cutter ensures even distribution of reinforcing elements within the mixture. A methodology for determining the productivity of the unit has been developed, considering the mixer filling volume, the geometric parameters of working elements, and mixing process characteristics. Formulas were derived for selecting key parameters of the cutter and roller feed for the fiber bundle.The proposed equipment contributes to improved quality of polystyrene concrete, reduced energy consumption, and shorter production time. Future research will focus on optimizing operating modes of the equipment for different types of polystyrene concrete mixtures using fiber reinforcement.
Copyright (c) 2024 Anna Anishchenko,Vladimir Blazko, Alevtina Aleinikova, Yulia Salenko https://creativecommons.org/licenses/by-nc-nd/4.0
Methods of accelerating the hardening of Portland cement without heat-moisture treatment, in the presence of complex chemical additives - hardening accelerators and finely dispersed crystallization centers, were considered. The study was divided into several stages, where the effect of each accelerator additive on the cement hardening process was investigated. Based on the results, both single and complex chemical additives were selected to accelerate the hardening of cement. The effect of finely dispersed crystallization centers on the cement hardening process was also investigated. Metakaolinite (palygorskite) was used as a dispersed additive, which was synthesized by the authors using kaolin clay and insoluble magnesium compounds and sulfate aqua complexes, iron-sodium alum. The effect of complex additives in various combinations on the properties of cement dough and hardened cement is presented. The optimal composition of additives is proposed, the use of which in combination with technological methods for manufacturing concrete products can provide an energy-saving effect in the production of building structures.
Copyright (c) 2024 Rasul Akhmednabiev, Oksana Demchenko, Olha Hukasian http://creativecommons.org/licenses/by-nc-sa/4.0
Diagnostics of load-bearing building structures of construction industry companies that operate under the influence of process liquids
Diagnosing load-bearing structures in construction industry enterprises exposed to technological fluids presents a unique set of challenges. These fluids, ranging from corrosive chemicals to abrasive slurries, can significantly accelerate the deterioration of concrete, steel, and other building materials. Effective diagnostics require a multi-faceted approach that considers the specific fluids involved, their concentration, temperature, and exposure duration. Visual inspections, supplemented by non-destructive testing (NDT) methods like ultrasonic testing, ground-penetrating radar, and impact-echo, are crucial for identifying hidden damage such as corrosion, cracking, and delamination. Furthermore, material sampling and laboratory analysis provide a definitive assessment of the extent of chemical attack and its impact on the structural integrity. Ultimately, a comprehensive diagnostic program enables informed decisions regarding repair, rehabilitation, or even replacement of affected structures, ensuring the safety and operational continuity of the enterprise.
Copyright (c) 2024 Oleksandr Semko, Yurii Avramenko, Alina Zyhun, Igor Petrikei, Artem Pleshynets http://creativecommons.org/licenses/by-nc-sa/4.0
Features of designing evacuation exits in the reconstruction of civil protection shelters for public buildings
In the context of the war in Ukraine, the issue of public safety has become acute. Civil protection measures include designing shelters or reconstructing existing basements. A component of the basement reconstruction is the redevelopment of evacuation exits from the shelters. The relevant current regulatory framework is analyzed. The object of the study is the building of an educational institution in the city of Poltava, built in the 19th century. A project for reconstructing the basement into a dual-purpose room with a separate emergency exit outside the building collapse zone has been developed.
Copyright (c) 2024 Olena Filonenko, Bohdan Tokar, Aleksej Aniskin http://creativecommons.org/licenses/by-nc-sa/4.0
Analysis of spatial planning solutions for civil protection structures according to regulatory requirements
The article presents an analysis of the normative-legal documentation regulating the construction and reconstruction of civil protection shelters in countries such as Israel and Ukraine. A comparative analysis method was employed to identify the differences in shelter requirements between the two countries. Specific technical requirements that significantly impact the design and construction process were highlighted. The study compared the approach to determining the required area of shelters in both countries for various facilities. An overview and description of the requirements for ventilation systems, water supply, drainage, and electrical connections were provided. Additionally, the general approach to selecting finishing materials and types of coverings for internal and external structural elements was described. Significant discrepancies in the requirements and approaches to the construction or reconstruction of shelters in these countries were identified. The findings can be used to enhance the efficiency of shelter design and construction in Ukraine, which is particularly relevant in the current context of increased risks to the civilian population.
Copyright (c) 2024 Olena Filonenko, Ihor Yurchenko, Тetiana Lvovska, Nataliia Mahas http://creativecommons.org/licenses/by-nc-sa/4.0
Analysis of trends in the development of load codes for building structures
The content of the article is a consistent review of approaches to considering loads on building structures and their reflection in regulatory documents of different years. Attention is focused on the continuity of the method of limit states and the method of permissible stresses in the part of the description of loads. With regard to climatic loads (snow, wind), attention is paid to changes in territorial zoning and calculation coefficients, the assignment of normative and calculation values and the involvement of experimental statistical data. Attention is also paid to the connection between the development of codes of crane loads and the results of experimental studies of these loads.
Copyright (c) 2024 Sergii Pichugin https://creativecommons.org/licenses/by-nc-nd/4.0
Strengthening of the cross-section of steel i-beams in the tension zone: a review of scientific research
The article reviews scientific research on methods and means of strengthening steel beam structural elements by increasing (building up) cross-sections using additional elements made of steel rolled profiles, plates, reinforcing bars and plates made of polymeric materials. The main conclusions and directions of further scientific research on effective methods and means of strengthening steel beam structural elements by increasing (building up) their cross-sections, which have the potential for widespread use in the repair and reconstruction of buildings and structures, are substantiated.
Copyright (c) 2024 Andriy Reka, Tatiana Galinska, Dmutro Ovsii, Mukhlis Hajiyev https://creativecommons.org/licenses/by-nc-nd/4.0
Technological features of foundation construction using vibro-reinforced soil-cement piles
The article examines the technological features of foundation construction using vibro-reinforced soil-cement piles. The technology is based on the bore-mixing method, which allows for pile formation without soil excavation, utilizing the existing soil as the main component of the soil-cement mixture. The use of vibro-reinforced soil-cement piles significantly increases the load-bearing capacity of foundations, reduces labor intensity in the construction process, and ensures the stable performance of the foundation in complex engineering and geological conditions. The article explores the specifics of the technological process of manufacturing vibro-reinforced soil-cement piles, particularly their formation, vibro-compaction, and the use of a high-frequency vibrator when embedding the reinforcement cage. It has been proven that the physical and mechanical properties of soil-cement piles, such as compressive strength, improve when deep vibrators are used in pile installation. A comparative analysis of vibro-reinforced and conventional soil-cement piles has demonstrated a significant increase in the load-bearing capacity of vibro-reinforced piles, which allows for a reduction in their number within foundation structures and leads to lower construction costs. Additionally, the article compares the soil cementation methods Jet Grouting, Pressure Grouting, and Deep Soil Mixing, which are used to improve soil bearing capacity and reduce deformations. Each of these technologies has its own characteristics that determine their effectiveness under different conditions. The advantages and disadvantages of each method are examined, including the ability to reach great depths, cost-effectiveness, and localized application.
Copyright (c) 2023 Oleksandr Novytskyi, Yevhenii Skrypka https://creativecommons.org/licenses/by-nc-nd/4.0