Modern technologies and methods of calculations in construction

Modeling the behavior of steel fiber reinforced concrete structures using the finite element method

2025-07-14T08:57:34+00:00

Abstract. The article examines the specific features of numerical modeling of steel fiber reinforced concrete (SFRC) structural elements using the finite element method (FEM). The relevance of the research is driven by the need for computer modeling and prediction of the stress-strain state of composite material structures, which is essential for the design of buildings and structures. The study analyzes approaches to incorporating steel fibers in numerical modeling, in particular, the discrete approach, where fibers are modeled as individual elements, and the homogenized approach, which is based on the averaging of the mechanical properties of the material in accordance with its composition. Examples of the implementation of these approaches in the software environments ABAQUS, ANSYS, and LIRA-FEM are provided. The accurate specification of input parameters and loading conditions has a significant impact on the reliability of the numerical simulation results.

Special attention is paid to modeling the nonlinear behavior of the material, including limit deformations, crack initiation and propagation, as well as the prediction of damage localization zones. The results of numerical modeling are analyzed and shown to be consistent with experimental (laboratory-scale) test data, particularly in terms of failure patterns, residual strength, and the energy absorption capacity of SFRC structures.

It has been determined that SFRC is characterized by increased crack resistance, alters the failure mechanism from brittle to ductile, and ensures the retention of load-bearing capacity after cracking. The finite element method is shown to be an effective tool for the quantitative assessment of the mechanical characteristics of SFRC elements, especially under combined loading conditions. The study concludes that FEM-based modeling is appropriate for use in engineering practice to justify structural solutions involving dispersed reinforcement in concrete structures.

Research of the optimal concentration of polypropylene fibers in coarse-grained crushed stone-sand mixtures reinforced with cement

2025-07-14T08:57:19+00:00

Recently crushed stone-sand mixtures are one of the most widely used road construction materials for the arrangement of base layers of road pavements in Ukraine. More and more often both mineral and combined binders are used to strengthen roads during construction, repairs and reconstruction. One of the ways to improve the properties of building materials is to reinforce them with various fibers. Analysis of literature sources has shown that the addition of fibers into the composition of cement-reinforced soils and cement concretes significantly improves the physical and mechanical properties and durability of these road-building materials.

The article presents the results of an experimental study on the establishment of the optimal content of polypropylene fibers on the physical and mechanical properties of coarse-grained crushed stone-sand mixtures reinforced with mineral binder (cement). The studies were carried out on a coarse-grained crushed stone-sand mixture reinforced with cement in an amount of 2%.

The results of the study showed that for these mixtures, according to the studied indicators, namely compressive strength and indirect tensile strength, the optimal content of polypropylene fiber with a length of 18 mm is 0.03% of the mass of the mineral part of the mixture. At these concentrations, the compressive strength limit increases by 3.4%, and the indirect tensile strength increases by 35%. It was found that a further increase in the concentration of polypropylene fibers from the optimal one leads to a negative impact on the indicators studied and levels their work in the material, as the mixture is oversaturated with fibers and a large number of them are knocked into bundles, which are unevenly distributed in the mixture and ultimately worsen the physical and mechanical indicators.

Training of building energy auditors by the new professional standard: status, challenges and prospects

2025-07-19T22:02:03+00:00

The article examines the current state and trends in the development of professional training for energy auditors in Ukraine, taking into account the latest challenges in the field of energy efficiency, decarbonization, and post-war reconstruction. Particular attention is paid to the analysis of the professional standard "Energy Auditor of Buildings", which has become a basic reference point for the formation of training programs that meet the requirements of European and national policies in the field of energy efficiency. The latest publications on the topic of training for energy auditors are reviewed, which emphasize the need for an interdisciplinary approach, harmonization of educational standards with European practice, and the introduction of innovative forms of training. The central theme of the study is a thorough analysis of the activities of the TEAD (Trainings for Energy Auditors & Technical Designers) program, which is implemented with the support of the European Union and aims to form a network of qualified specialists in the field of energy auditing. The paper details the key components of the TEAD program in 2023–2025: development of training courses by the professional standard, training of trainers based on leading Ukrainian higher education institutions, conducting certified training for energy auditors of buildings and processes, and implementing the principles of gender equality in the educational process. The TEAD project is considered one of the most effective examples of international partnership in strengthening human capital, for the implementation of sustainable development goals in Ukraine in cooperation with leading European and Ukrainian experts, which confirms its relevance and compliance with modern requirements. The article may be useful for educators, researchers, energy efficiency specialists, as well as for representatives of state bodies responsible for the implementation of energy modernization policies

Analytical and theoretical principles of optimizing organizational construction processes

2025-07-19T20:07:08+00:00

In the current conditions of the construction industry, there is an increasing need for a comprehensive transformation of organizational processes, which is due to the increasing complexity of infrastructure projects, uneven distribution of resources, market dynamics, and increased requirements for the quality and timing of work. The results of the analysis of the development of the construction market of Ukraine for 2017–2022 showed the presence of several structural imbalances, in particular between the planned volumes of construction and installation works and actual implementation, and also revealed regional asymmetry of demand, which is due to socio-economic factors.

In conditions of such instability, effective management of construction activities requires the use of mathematical methods that can take into account the multifactorial nature of processes. One of the promising areas for improving planning and coordination in construction is the use of mathematical modeling, in particular, the algorithmic-criteria approach to parametric optimization. This approach allows for a formal analysis of the dependencies between the main indicators of project implementation: time characteristics, logistics of material supply, fixed-interval inventories, cost of work, transportation costs, and volumes of construction and installation works. At the same time, mathematical modeling contributes not only to increasing the accuracy of calculations but also makes it possible to determine optimal solutions in conditions of limited resources and a changing external environment. Thanks to a systematic approach to analysis and planning, it becomes possible to more effectively manage the interaction between contracting structures, predict the results of project implementation, and reduce the risks of their failure.

Thus, the study's relevance lies in the need to develop effective mathematical tools for optimizing organizational and technological processes in construction, based on a combination of methods of applied mathematics, systems analysis, and a criteria-based approach to construction production management.

Ways of post-war reconstruction of transport infrastructure

2025-07-19T22:01:14+00:00

The concept of sustainable mobility began to spread in the late 90s of the last century, simultaneously with the concept of sustainable development, and as one of its components. For the first time, the term "sustainable mobility" began to be used in the 2000s. Transport infrastructure is the main connecting link of all districts of the city, provides communication between regions, and should become one of the main drivers in the post-war reconstruction of Ukraine. One of the most important trends in urban development is the transition to the formation of a sustainable transport infrastructure, the main tasks of which are: reducing the demand for private transport and encouraging the use of more energy-efficient and environmentally friendly public transport modes (trolleybus, tram).

Even before the beginning of 2022, the KP "Severodonetsk Trolleybus Management" began to implement the concept of an environmentally friendly transport carrier. Road bridges have always played a strategic role, but during the hostilities, their importance in transport communication became critical, as they were partially or destroyed. The destruction of transport infrastructure, especially road bridges, which are the main means of communication for residents of the city of Siversko-Donetsk, as its residents have rail connections from Lysychansk and Rubizhne, where there are railway stations. Since 2014, hostilities have been taking place in the territory of the Luhansk region. The cities of Siversko-Donetsk, Rubizhne, and Lysychansk form the Lysychansk-Siversko-Donetsk agglomeration, the connection within which is carried out by two road bridges across the Siversko-Donetsk and Borova rivers. In 2014, they became unusable. Projects to rebuild automobile bridges across the Siverskyi Donets and Borova rivers and to lay contactless trolleybus routes are a very important factor in the restoration of the region's cities and the formation of a sustainable transport infrastructure of this agglomeration.

Problems of operational reliability of monolithic buildings and structures in case of non-compliance with the requirements of sequential concreting

2025-07-19T22:00:10+00:00

Operational and structural reliability is the most important criterion for the life cycle of monolithic buildings and structures.

One of the most important processes in the construction of a building is the sequential concreting of structures. In fact, the construction of a building is carried out gradually; therefore, at the joints of structures, there are zones where, during the technological process, breaks in concreting are performed, which leads to the appearance of a thin layer of cement film, which does not meet the technical characteristics of concrete and must be removed before laying the concrete mixture of the next layer. Unfortunately, as practice shows, builders do not always comply with these requirements, which can lead to accidents.

The article presents real cases of such situations in construction.

At one of the construction sites, an inspection was conducted of the structures prepared for closing the formwork and subsequent concreting. It was noted that the previous cement surface of the floor slab was not cleaned properly, and grease, which is used to lubricate the formwork, had leaked onto the surface of the slab. In another case, the technical engineer recorded a situation where the previous cement surface was not cleaned off the objects, and construction dirt and spots remained. For another example, the concreting of columns at one of the sites was suspended, and the formwork was opened. Many welding residues were found on the concrete surface in the column area and other defects. In all other cases, after placing the concrete mix in the structure and its hardening, we cannot speak about the integrity of the concrete. Therefore, design and calculation models do not work.

What are the consequences of such deviations from the design? As practice has shown, over time, this can lead to an accident or become part of the reason why an accident occurred. As an example, we can consider the situation that happened in the year 2023 at one of the boiler houses in the city of Odessa. After examining the destroyed parts and the corresponding reports, it was noted that the destruction occurred clearly along the concreting seams. The destroyed part of the chimney was divided into blocks, each of which is limited by these seams. As the examination showed, the accident occurred for several reasons, but one of them was the lack of a competent organization of the concreting seam.

Therefore, when carrying out concrete work, it is important to ensure that there are no interruptions during concrete pouring and to ensure that the control over the breakdown of the work is carefully explained to engineers and workers, as well as the importance of surface preparation during concrete pouring.

Modeling and calculation of a three-layer composite shell of the “cone-cylinder-cone” type

2025-07-19T21:58:31+00:00

The article presents the results of calculating a multilayer structure of the “cone-cylinder-cone” type under the action of force and temperature loads. Multilayer structures and systems made of them are widely used in various industries where a combination of several properties is required - for example, strength, thermal insulation, sound insulation, resistance to moisture, fire, etc. The main areas of their use are construction, industry, automotive and aviation, military, and space technology. The calculation of multilayer structures has several features that distinguish it from single-layer systems, since it is necessary to take into account the interaction of layers, their physical and mechanical properties, and fundamental purpose. Such a calculation requires taking into account anisotropy, interlayer interaction, thermal, and mechanical loads. For this purpose, complex models are created that make it possible to more accurately predict the behavior and durability of the structure. There are several theoretical approaches to the calculation of multilayer structures, and the choice of theory depends on the type of structure, its thickness, type of load, as well as the required accuracy.

The research is based on a variant of the finite-shear theory of calculation of multilayer plates and shells, taking into account temperature in hypotheses for transverse tangential stresses. At the first stage of the research, the problem of stationary thermal conductivity of a multilayer shell was solved, in which the hypothesis of temperature distribution over the thickness of the multilayer package was applied. Based on the obtained characteristics of the temperature field, the problem of thermoelastic equilibrium of a composite shell was solved. The obtained boundary value problems of thermal conductivity and thermoelastic equilibrium were implemented by the method of discrete orthogonalization.

As follows from the constructed graphs, the deflections and stresses that arise under the action of a temperature field are 4-20 times higher than the similar values obtained under force loading. This indicates that the temperature effect is the determining factor of the stress-strain state of a composite shell.

Numerical modeling of load-bearing corrugated board using. An equivalent orthotropic plate

2025-07-19T21:55:13+00:00

Due to their high efficiency in terms of weight-stiffness and weight-strength, profiled steel sheets are widely used in modern construction as load-bearing elements for roofs, floors, and sandwich panels. The peculiarities of their design determine their pronounced orthotropic behavior, which requires special approaches to numerical modeling. While traditional three-dimensional finite element models provide high accuracy, they are excessively resource-intensive for practical design in the LIRA-CAD and SCAD Office software environments. This creates an urgent need for simplified, but at the same time sufficiently accurate, equivalent models. In this paper, we propose a numerical and analytical methodology for replacing corrugated sheeting with an equivalent orthotropic plate that reproduces the main characteristics of the sheet's bending stiffness in the main directions. Virtual experiments in the LIRA-SAPR environment allowed us to obtain the maximum deflections of the corrugated board under load along and across the stiffeners, which served as the basis for calculating the equivalent elastic moduli, Poisson's ratio, and shear modulus. The verification of the results confirms the ability of the orthotropic model to adequately reproduce not only the deformation behavior, but also allows for the assessment of the strength of the profiled plate under a typical load. The developed approach allows engineers to use simpler plate models in design calculations without losing accuracy, which is especially valuable in problems with a large number of elements. The usefulness of the proposed model will be especially noticeable when modeling large areas of roof coverings and in optimization design, where speed and computing resources are critical. The developed model allows us to effectively assess the permissible loads on corrugated board according to the criteria of maximum deflection and strength, taking into account the options for support and the length of the spans.

Оцінка властивостей крупних заповнювачів із дроблених гірських порід західного регіону України для виготовлення бетонних сумішей

2025-07-20T15:14:21+00:00

The article investigates the physical and mechanical properties of coarse aggregates obtained by crushing sedimentary and igneous rocks, which are widely used in the construction industry in the western region of Ukraine. Key parameters such as density, porosity, compressive and split strength, grain size distribution, clay and dusty particles, and grain shape, which have a critical impact on the quality of concrete mixtures, were evaluated. The study examined five types of aggregates of different mineralogical origin, including granite, gravel, sandstone, and andesite materials. It turned out that their physical and mechanical properties depend not only on the mineralogical composition, but also on the conditions of formation, mining methods, and technological processing. A comparative analysis showed that granite crushed stone generally demonstrates better physical and mechanical characteristics, including high strength, low content of harmful impurities, and optimal grain size distribution, which ensures an even distribution of stresses in concrete and contributes to the durability of structures. At the same time, other types of aggregates can be competitive due to their economic feasibility and availability, making them an effective alternative for different classes of concrete depending on project requirements. The study also takes into account the environmental aspects of using local raw materials, which helps to reduce the carbon footprint of construction by reducing logistics costs and rationalizing the use of natural resources. In addition, the possibilities of increasing the efficiency of aggregates by modifying them, in particular the use of surface treatments to improve adhesion to cement stone, are considered. The results presented are of practical importance for optimizing the composition of concrete mixtures, developing regulatory requirements for the quality of aggregates, and improving the manufacturability of concrete structures. The findings can be used by design organizations, concrete product manufacturers, and construction companies to improve production efficiency, ensure the durability of construction projects, and reduce the environmental impact of the construction industry.

Дослідження роботи фібробетону при використанні різних армуючих волокон

2025-07-20T15:22:32+00:00

This article presents the results of an experimental study on the mechanical behavior of fiber-reinforced concrete using various types of dispersed reinforcement, including steel, polypropylene fibers. The primary objective of the study is to evaluate the effect of fiber type and content on compressive strength, flexural tensile strength, and crack resistance under service load conditions. The main advantages of fiber-reinforced concrete structures include the reduction of labor costs associated with traditional reinforcement works and the integration of technological operations — the processes of mixing, reinforcing, placing, and compacting occur simultaneously.

The experimental program was based on the principles of mathematical planning, which allowed for a reduction in the volume of tests while ensuring the reliability of the results. It was found that the introduction of fibers significantly increases the ductility and durability of concrete, especially under flexural and cyclic loading.

The study demonstrated that combined reinforcement (with steel and synthetic fibers) creates a synergistic effect, improving the crack-bridging capacity of the concrete and increasing its fracture resistance. The use of polypropylene fibers contributes to a reduction in water permeability and enhances the concrete's performance in aggressive environments. The findings confirm the feasibility of using fiber-reinforced concrete as an effective material for rigid pavement structures and other construction elements subjected to intensive loading and adverse environmental conditions.

An increase in fiber content leads to an increase in flexural strength at all stages of hardening and demonstrates a non-linear (extremal) character. This indicates the existence of optimal dosages for steel fiber (80–100 kg) and polypropylene fiber (2–3 kg). The combined use of steel and polypropylene fibers allows for an increase in the efficiency coefficient of dispersed reinforcement, defined as the ratio of flexural tensile strength to compressive strength.

Аналіз нормативних вимог щодо проєктування перетинів з урахуванням безпекових умов у міському середовищі

2025-07-20T16:56:14+00:00

This article presents the findings of a study examining the inconsistencies in the design parameters and elements of intersections within urban areas in Ukraine, particularly during the planning or reconstruction stages. These parameters are regulated by a range of legislative acts and construction standards. The research highlights the problematic misalignment between regulatory literature and state laws, rules, and strategic frameworks, which inherently leads to errors in the development of street and road infrastructure across urban settlements of various sizes (metropolitan, large, medium, and small cities, as well as townships). The study draws on the work of leading Ukrainian researchers who consistently address urban development issues and traffic accident risks in urban road networks. Key directions have been identified to ensure mandatory safety conditions during the design and reconstruction of intersections used by private vehicles, public transport (including taxis), and specialized vehicles. Special attention is given to the "visibility triangle" parameter, a critical element in the preparation of design documentation, including during the reconstruction of intersections. The study outlines the components and regulatory sources that define this parameter, providing a comprehensive analysis and systematization of relevant requirements. Furthermore, it highlights a major discrepancy regarding speed regulations on urban road networks, which contributes to potential traffic accidents at intersections in cities and towns. The article substantiates the consequences of failing to harmonize construction norms with national legislative and regulatory frameworks

Наукові підходи до оцінки енергоефективності будівель

2025-07-20T17:10:16+00:00

The research explores modern scientific methods for building energy efficiency assessment within present-day global sustainability frameworks. The growing need to decrease energy usage while improving indoor environmental quality makes advanced energy-saving technologies essential for adoption. The research examines new approaches to energy modeling and analysis by emphasizing mathematical modeling as an effective prediction tool for building energy performance. The method enables researchers to build precise physical models of thermal and energy processes, which allows them to include building-specific architectural features and climatic conditions, and operational parameters in complete energy assessments.

The main focus should be placed on artificial intelligence, together with its machine learning algorithms that operate within deep learning technologies and artificial neural networks. The system enables automatic processing of sensor and monitoring data, and remote sensing system data in large quantities. The new approach has resulted in better prediction accuracy and model adaptability to actual conditions. The research investigates contemporary methods for assessing energy efficiency through actual versus predicted consumption comparisons. The research investigates remote sensing of Earth's capabilities to detect heat losses and building defects and evaluate energy states through satellite or aerial photograph data analysis.

The research focuses on how Building Information Modeling technologies (BIM) combine with Life Cycle Assessment (LCA) methods to evaluate energy efficiency across all phases of building development, including conceptual stages, design, construction, operational use, and maintenance.

The research discusses potential advancements of these approaches in the digital transformation of the construction industry. The introduction of "smart" building management systems (Smart Building Systems) along with Internet of Things (IoT) integration and compliance with modern European and international standards for energy efficiency

Influence of production specifications on the mechanical properties of 3D printed polymer elements

2025-07-20T17:20:21+00:00

This article presents the results of a study of the polymer filament manufacturer's influence on the mechanical characteristics of samples manufactured by the FDM (Fused Deposition Modeling) 3D printing method. The work aimed to determine the dependence of the strength properties of printed parts on the quality of raw materials from different filament manufacturers when using the same printing parameters. The experiment used four groups of samples of the same type and size, printed from filament from various manufacturers, on the same 3D printing installation with fixed technological parameters.

Mechanical tensile tests with longitudinal force were carried out on the universal testing machine MI-40KU with recording of the stress-strain state of the sample. To quantify the mechanical strength, the tensile elasticity and yield strength, Young's modulus, and elastic and plastic deformation in the yield zone were determined. The results obtained showed a significant variation in mechanical properties depending on the filament supplier, which is due to differences in polymer composition, degree of drying, impurities, and filament manufacturing technology.

The study demonstrates the critical importance of choosing high-quality material when designing and manufacturing critical parts using FDM printing. The data obtained can be used by 3D printing users, for whom it is important to choose not only the right type of filament, but also a manufacturer whose product will satisfy their needs in the manufacture of critical parts. The results demonstrate the importance of preliminary testing of materials before they are used in critical products. In addition, the load and strain graphs confirmed the analytical observations and provided a deeper understanding of the behavior of each type of sample under force loading.

The influence of ground blast furnace slag and plasticizing additive on the strength properties of road concrete

2025-07-21T19:01:22+00:00

The article presents results of the latest generation of different dosages of polyacrylate superplasticizer Dynamon SP 1 in a wide concentration range influences the strength properties of road concrete based on Portland cement with partial replacement with ground blast furnace slag. To compare the strength properties, concrete based on Portland cement without replacement with ground blast furnace slag and with the addition of polyacrylate superplasticizer Dynamon SP 1 in the same range was also studied. Experimental studies of the change in compressive and flexural tensile strengths of a Portland cement-based mortar with its partial replacement with ground blast furnace slag in the range from 0% to 20% were conducted. It was concluded that the Portland cement replacement in an amount of 10-14 % with ground blast furnace slag is quite acceptable, which is due to a moderate decrease in strength indicators. The concentration of the acrylic superplasticizer Dynamon SP 1 was determined, which corresponds to the maximum compressive and flexural tensile strengths of сementconcrete based on Portland cement without partial replacement with ground blast furnace slag. This concentration is 1 % for compressive strength and 1,25 % for flexural tensile strengths. The concentrations of the superplasticizer Dynamon SP 1 were also determined, which provide the maximum compressive and flexural tensile strengths of concrete based on Portland cement with partial replacement with ground blast furnace slag. It turned out that the maximum value itself with the use of Portland cement with partial replacement with ground blast furnace slag is somewhat smaller, compared to the maximums when using Portland cement without partial replacement with ground blast furnace slag: for compressive strength by 3-10% and flexural tensile strengths by 6-9%, depending on the amount of binder. It was also found that the superplasticizer concentration corresponding to the maximum flexural tensile strength of concrete based on Portland cement with partial replacement, compared to concrete based on Portland cement without partial replacement, is somewhat different. The value of this concentration is 1,1 %

Numerical FEM modeling of deformation solid and glulam reinforced timber beams

2025-07-21T19:17:50+00:00

The article presents the results of numerical modeling of the deformation of wooden beams made of laminated and solid timber, performed using the LIRA-SAPR 2024 R2.3 software suite, which utilizes the finite element method (FEM). The possibility of using this software for the design of reinforced timber structures, an issue relevant to the reconstruction and reinforcement of building elements, is explored. The modeling process enables a detailed analysis of the stress-strain state of structures, predicting their behavior under load, and comparing the results with experimental studies and traditional deformation methods. The modeling was carried out taking into account the orthotropy of timber, for which three-dimensional finite elements were used to describe the material's mechanical properties. Specifically, the elastic moduli along and across the grain of the wood, as well as Poisson's ratios, were incorporated, determined experimentally. Reinforced elements were modeled using analogous elements representing carbon strips and steel reinforcement. The obtained numerical results were compared with experimental data and results derived using the deformation method. Statistical analysis showed that the numerical modeling in the LIRA-SAPR software suite has an average deviation from the experimental data of 21% for laminated timber beams and 6.5% for the deformation method. For reinforced beams, the deviation was 29% for FEM and 7.3% for the deformation method. The results of the numerical modeling showed that the LIRA-SAPR software suite allows for the accurate determination of stresses and deformations in wooden structures; however, the deformation method demonstrated higher accuracy for reinforced elements. Statistical analysis confirmed that both approaches are effective for design, particularly for reinforced timber structures, while the deformation method proves to be more accurate under increased load conditions. It was concluded that for the design of reinforced timber structures, both approaches can be used depending on the required accuracy and modeling speed

Research on the change of mechanical characteristics under the influence of ultraviolet in rigid polyurethane foams

2025-07-21T19:36:38+00:00

The paper investigated the influence of ultraviolet (sunlight) as a degrading factor on the change in the mechanical characteristics of rigid polyurethane foams (PPU). Experimental studies were performed for groups of samples obtained in laboratory conditions. Mechanical characteristics were determined based on the results of tests of experimental samples under the action of a compressive load simulating static deformation. Polyurethane foam was obtained by pouring a two-component polyol-polyisocyanate mixture with weight fractions of components 1:2. The appearance of PPU compositions is described.

Mechanical characteristics were determined based on the results of tests of experimental samples under the action of a compressive load simulating static deformation. According to the load diagrams under static compression, Young's modulus, proportional limit, plastic limit, and relative residual deformation were determined 5 min after unloading the sample. The studies were conducted for two series of samples, one of which was freshly manufactured and without exposure to ultraviolet light, and the second series of samples was exposed to ultraviolet light for three months. The results of the studies of two series of samples were compared, and changes in the mechanical characteristics of rigid polyurethane foams caused by the influence of UV radiation were established.

The state of the surface of the cross-section of the UV-irradiated sample was assessed and it was found that the inner part of the UV-irradiated samples, unlike the outer surface, did not undergo yellowing of the material, which may indicate the preservation of the chemical structure of the polyurethane foam and its components in the inner layers of the material. The thickness of the degraded surface layer of the foam due to the influence of ultraviolet light for 3 months was determined.

It was established that the effect of UV radiation (exposure duration 3 months) causes a slight but not critical change in the mechanical characteristics of rigid polyurethane foams. However, it is recommended to protect PPU elements from prolonged exposure to ultraviolet light to prevent their degradation, preserve functional properties, and prevent premature aging.

Numerical analysis of the strength and stiffness of a hollow-core slab made of high-strength rapid-hardening concrete

2025-07-23T20:03:15+00:00

High-strength, rapidly hardening concrete combines high early strength with increased structural density, making it a promising material for the efficient production of precast concrete structures. The article presents the results of numerical modeling of the stress-strain state of a reinforced concrete hollow-core slab using a volumetric finite element model implemented in the LIRA-SAPR software package. Unlike traditional approaches based on plate finite elements, this work develops a comprehensive volumetric model that accounts for the actual geometry of the voids, enabling a more accurate description of the local stress distribution within the concrete body of the structure. Given the complex topology of the slab, the finite element mesh was formed using a combined approach. During model triangulation, both six-node and eight-node volumetric finite elements were employed simultaneously to balance descriptive accuracy and computational efficiency. Physically nonlinear universal spatial finite elements were applied, with the deformation properties of concrete described by an exponential deformation law. The prestressed reinforcement was modeled using universal spatial rod finite elements, and its mechanical properties were defined by the Prandtl diagram. The calculations determined the distribution patterns of internal forces, deflections, and stresses, particularly in the region of maximum bending moment and in the anchorage zones of the reinforcement. An approximate value of the ultimate useful load was established at which the structure reaches the limit state in terms of stiffness while satisfying the strength condition. The strength assessment was performed using the Coulomb-Mohr criterion, which accounted for the complex stress state, including principal stresses, and reflected the characteristic disparity in concrete’s tensile and compressive strength limits.

Thermal insulation of buildings with complicated facades

2025-07-23T20:03:12+00:00

Energy efficiency measures will significantly reduce the burden on the country's energy system, especially during the heating season, as they will significantly reduce losses through the building envelope and communications. Rising tariffs are a powerful incentive for the comprehensive thermal modernization of buildings.

Energy efficiency measures not only save money but also contribute to the comfort of thermally modernized buildings. Insulation of building envelopes plays a leading role in this. First of all, these are exterior walls, roofs, and floors. When planning insulation measures, it is important to comply with current norms and standards. According to statistics, a significant number of modernized buildings use a “prefabricated system design with lightweight thin-layer plasters”.

For this technology, surface evenness is important, which is not always present. Existing buildings were erected in different periods, and different technological methods and design solutions were used to give them architectural expressiveness. Insulation of such facades causes certain difficulties, and sometimes a significant increase in price due to an increase in the amount of materials or labor intensity of work when preparing the surface of structures for insulation.

There are three types of irregularities in brick facades in buildings of different “age groups”:

- Curly brickwork with slight protrusions (up to 10 cm) beyond the main surface of the facade. It is most often found in Soviet-era buildings in the form of simple geometric shapes.

- Figured brickwork is usually found in historic buildings of the last century and the century before last. A significant part of these buildings may have the status of an architectural monument. Renovation of such buildings is always individual and is beyond the scope of this study.

- buildings (mainly public buildings) with pilasters and buttresses (pseudo-buttresses) on the facades. The third type will be the object of our research.

Design features of the mastic asphalt composition

2025-07-23T20:03:11+00:00

Mastic asphalt concrete is a type of hot asphalt concrete that differs significantly from hot asphalt concrete in terms of particle size distribution, nomenclature of indicators used to assess quality, and technology for manufacturing, transporting, and paving. These features of mastic asphalt concrete must be taken into account when designing its composition. One of the operations performed during the design of a mastic asphalt concrete composition is the manufacture of samples, with the subsequent establishment of physical and mechanical quality indicators and comparison of the results with regulatory requirements. Unlike traditional hot asphalt concrete, the design of which (in particular, the determination of the amount of bitumen) is based on strength indicators (compressive strength at 50 °C and 20 °C), the optimal bitumen content in the composition of mastic asphalt concrete according to the requirements of the national standard DSTU 9290-6 is determined by the residual porosity and operational plasticity (stamp indentation). In the presented work, the optimal content of bitumen of the BND 35/50 brand in the composition of a mastic asphalt mix of the LABS-10 type was selected. According to the data obtained, it was found that the optimal amount of bitumen is 11 %, and the temperature of preparation of the mixture is 180 - 200 ºС. In the case of taking into account the serviceability of mastic asphalt concrete, determined by the stamp indentation index, the optimal amount of bitumen is reduced to 9 %, and the mixture preparation temperature is increased to 220 - 240 °C. Based on the results of the assessment of technological plasticity determined by the Luer method, at a temperature of 200 - 230 °C, the mastic-in-place mixture used in the work will be too stiff, which will make it impossible for it to spread during the process of laying on the road surface. Taking into account the three main quality indicators of mastic asphalt concrete, such as residual porosity, operational and technological plasticity, it is advisable to use a mastic asphalt concrete mixture with 10 % BND 35/50 bitumen produced in the temperature range from 235 to 270 °C. When designing the composition of mastic asphalt mixtures, it is necessary to take into account the value of technological plasticity, since this approach allows ensuring the manufacturability of pavement construction and compliance of physical and mechanical parameters with the standardized values.

Parametricism as a Style in Architecture and Design: Concept, Methodology, Computer Tools, and Development Prospects

2025-07-23T20:03:10+00:00

This paper explores the interrelation of the triad of fundamental methodological principles of parametricism as a contemporary style in design and outlines several new prospects for the development of the parametric style.

The concept of parametric style is defined as an architectural and design system in which all elements and complexes are flexible and subordinate to parametric logic. The primary tool for achieving such logical flexibility is the algorithmization of functional relationships between multiple parameters of all components within the design process.

The methodology of parametricism is based on the principle of constructing natural systems, where forms emerge as a result of the interaction of factors that organize complex and seemingly disparate elements into a coherent structure.

An analysis of the most popular computer programs for parametric 3D modeling has been conducted. Based on the results, a classification of these programs has been developed according to their effectiveness as tools for shaping parametric style in various fields of design.

The promising directions for the further development of parametric style include: the use of AI-based generative design; bionic and adaptive design; the integration of parametric design into dynamic virtual environments (AR/VR); robotic and digital manufacturing; and the active implementation of climate-oriented design. The advancement of these areas will open new opportunities for the parametric style by enabling the transfer of designed objects into virtual environments and by simulating the impact of design parameters on the qualitative characteristics of design solutions.

Special attention is given to Discrete Voxel Parametric Design as a novel approach to parametric modeling. Its core idea lies in the fact that complex forms are represented not through traditional parametric curves or surfaces, but through discrete elements – voxels. Each voxel can carry its own set of parameters, enabling more detailed and flexible modeling of complex and adaptive structures across various fields of design and project development.

Sandwich panels with basalt, mineral wool, and expanded polystyrene insulation: a comparative analysis of properties based on experimental research

2025-07-24T12:05:43+00:00

The article explores the structural and technological features of using wall sandwich panels with basalt insulation, taking into account modern requirements for energy efficiency, fire safety, and mechanical strength. A comparative analysis of the key physical and mechanical characteristics of the three main types of insulation materials most commonly used in sandwich panels is conducted: basalt fiber, mineral wool, and expanded polystyrene (EPS). The study summarizes and systematizes the results of leading experimental research on the thermophysical, strength, fire-resistant, and technological properties of sandwich panels. Particular attention is paid to the behavior of materials under elevated temperatures, which is critically important for preventing fire spread. According to the obtained data, basalt insulation materials demonstrate the highest fire resistance, stable thermophysical properties at temperatures up to 300 °C, as well as high compressive and flexural strength. It was found that mineral wool provides good thermal insulation, although it has lower strength and temperature stability. Expanded polystyrene, while showing satisfactory thermal conductivity at low temperatures, significantly loses its properties when heated above 60 °C. Overall, these studies allow for a well-grounded assessment of the structural limitations and advantages of each type of insulation in terms of durability, safety, and energy efficiency. The results may be useful for improving sandwich panel designs, selecting suitable insulation materials according to operating conditions, and enhancing the overall performance and safety of buildings.

Effective schedule planning for bus routes with intersections

2025-07-24T12:05:41+00:00

This paper examines the optimization of public transport schedules to reduce passenger waiting times and improve overall efficiency. Efficient scheduling is crucial in urban transportation, where delays and long headways lead to overcrowding and passenger dissatisfaction. Addressing these challenges requires advanced mathematical modeling and algorithmic approaches. During the research, various optimization techniques were explored, with particular emphasis on the greedy algorithm, initially considered due to its intriguing name. Despite its simplicity, this algorithm showed significant potential for solving scheduling problems by making locally optimal choices at each step. The implementation of this approach was analyzed and compared to traditional scheduling methods.

A key contribution of this study is the development of an optimization framework integrating the greedy algorithm into public transport scheduling. The proposed method enables efficient adjustment of bus arrival times and minimizes headways between consecutive vehicles. The implementation code plays a crucial role in supporting this framework, allowing real-time adjustments and optimized schedules. To validate the proposed approach, experimental testing was conducted on bus routes in Lutsk. Results showed a 30% reduction in average travel time compared to conventional scheduling. Optimized schedules also improved passenger distribution, reduced congestion, and enhanced service reliability. This research provides valuable insights for urban transport planning, highlighting the potential of algorithmic optimization. Future work may integrate dynamic demand fluctuations and multimodal transport networks to refine scheduling strategies.

In the Introduction section, we review the literature and state the aim and objectives; Materials and Methods describes the uncertainty assessment and numerical implementation; Results and Discussion presents the simulation statistics and a real-data example; the Conclusions highlight the universality and practical value of the proposed algorithm.

Bayesian approach to circle diameter estimation from chord lengths

2025-07-24T12:05:39+00:00

. This study presents a method for estimating circle diameters based on chord length measurements, which proves particularly valuable for analyzing 2D cross-sections of three-dimensional structures where direct diameter measurement is impossible. The method employs a Bayesian approach that incorporates both the geometric properties of circle chords and prior assumptions about diameter distributions. The author developed a Python algorithm that requires only input data in the form of measured chord lengths and automatically computes the most probable diameter value, its confidence boundaries, and measurement accuracy estimates. Key advantages of the proposed solution include a user-friendly implementation with no need for complex computations, independence from specialized software, open-source availability (via a public repository), and reliable performance even with limited measurement data. Potential applications span multiple disciplines, including materials science (microstructure analysis), nanotechnology (nanoparticle characterization), and stereology (3D parameter reconstruction from 2D sections). The method’s principal innovation lies in its optimal combination of theoretical rigor and practical accessibility, making it an effective research tool. By enabling accurate diameter estimation from chord measurements, it overcomes a fundamental challenge in stereometric analysis of circular objects. The algorithm’s robustness with small datasets and its open availability position it as a valuable resource for researchers across relevant fields.

Research on the impact of consumer properties of horizontal markings on road safety

2025-07-24T12:05:38+00:00

The article provides information on the state of road safety in Ukraine. Road traffic, in which a person, a car and a road directly participate, takes place in a formed environment. Road safety is one of the most pressing problems of our time. To prevent a significant part of road accidents, it is necessary to install high-quality and timely road markings. Road markings are an effective means of organizing vehicle traffic, which contributes to improving road safety, reducing the number of road accidents, increasing the speed of cars and the carrying capacity of the road. Road markings play a key role in shaping the behavior of drivers on the roads. Clear and visible lines help drivers to better navigate, understand the boundaries of their lanes and follow the rules of the road. The article formulates the functional goals of road markings and presents a model of the impact of road markings on the driver of a vehicle, as well as formulates and presents a diagram of the consumer properties of horizontal road markings. Consumer characteristics of horizontal road markings are a set of target, criterion and evaluation and measurement indicators formed taking into account its functional goals, taking into account the interests of its users, at all stages of its life. The main functional goals of road markings are ensuring active safety, informing road users, aesthetics, environmental friendliness, economy, functional durability, manufacturability of construction and demarcation.

To ensure safe traffic conditions, it is necessary to carry out systematic quality control of road markings and materials used in order to timely detect non-compliance of the established parameters with regulatory requirements.

Features of the methodology for integration engineering networks with a heat pump in building in the valley of Sapalayivka River in Lutsk

2025-07-25T19:49:28+00:00

Analysis of literary sources revealed stable trends: the technical and technological development of engineering networks in the direction of utilizing smart and intelligent technologies; and increasing requirements for energy efficiency and environmental friendliness of engineering networks and construction objects that integrate these networks. Examples of hydromorphological transformation of urban rivers were analyzed. A conclusion was made about the importance of preserving the Sapalaivka ecosystem for Lutsk.

The features of the existing urban landscape of Lutsk around the Sapalaivka River were analyzed. The condition of the City Park recreation area in the valley of this river was analyzed in more detail. New changes in the urban landscape of the southern slope were noted: it was reinforced with a reinforced concrete wall with buttresses. The construction of a public building with the integration of engineering networks with a heat pump is planned near the slope.

An improved research methodology was developed, which provides for a comprehensive analysis of the characteristics of the research object. Urban planning, environmental, socio-economic, architectural, and construction aspects are analyzed. This scientific approach allows achieving the most balanced technical solutions in the design process. Their implementation will contribute to achieving better results in the integration of engineering networks into construction objects. The design results were obtained in the Uponor software environment. To conduct the analysis within the framework of the developed methodology, it is proposed to involve well-known methodological approaches. Depending on the needs of the analysis, they can be of varying mathematical complexity: from the principles of SWOT analysis to methods of analysis and/or optimization with obtaining objective functions. Optimization is recommended to be carried out in one stage (determine the objective function depending on the factors that are indicators of aspects) or in two stages (when the indicators of aspects are also determined as an objective function from the factors in each aspect). The developed methodology is recommended to be used as a methodological approach to solving complex design solutions for the integration of engineering networks into construction objects. It improves the consistency of such solutions with urban planning and environmental requirements for the urban landscape.

Integration of glass into architecture and urban development

2025-07-25T19:49:25+00:00

The article examines the main directions of glass integration into modern architecture and its impact on the development of urban space of cities. Glass, as a universal and at the same time complex architectural material, plays an important role in the formation of new aesthetics, functionality and environmental friendliness of buildings, especially in conditions of increasing density of the urban environment. Its use allows for transparency, lightness of structures, improved natural lighting, and visual expansion of space, which meets the challenges of modern urban planning.

Attention is focused on architectural trends of the 21st century, in particular, on the spread of glass facades, roofs, partitions, and other structural elements in residential, public, administrative, and infrastructure buildings. Examples from leading world megacities, such as London, New York, as well as Ukrainian cities – Kyiv, Lviv, Kharkiv – where architecture with a significant proportion of glass elements contributes to the renewal of the urban environment, the creation of an open, bright, interactive space are analyzed.

Particular attention is paid to issues of energy efficiency and sustainable development. It is noted that the use of the latest technologies in glass production (energy-saving, selective, multifunctional glass, triplex, double-glazed windows with inert gas) helps reduce the energy consumption of buildings, increases their thermal insulation, reduces the carbon footprint and complies with the principles of green architecture. Glass structures also open up wide opportunities for the integration of renewable energy sources – photovoltaic panels, active facades and solar batteries.

Development of a new technology for determining the tire–pavement friction parameters

2025-07-25T19:49:23+00:00

The frictional properties of road surfaces are among the most critical transport-operational characteristics, directly affecting road traffic safety. They determine the ability of vehicle tires to maintain contact with the pavement during movement, especially when accelerating, braking, or changing direction. Insufficient grip can lead to skidding, increased braking distance, and loss of vehicle control, all of which significantly raise the risk of traffic accidents. Currently, there are several methods for evaluating pavement friction, but most of them are labor-intensive, resource-demanding, and do not provide complete coverage of the road surface. Furthermore, many traditional methods rely on spot measurements, which can result in missing potentially hazardous sections.

This article proposes a new approach to assessing the frictional properties of road surfaces based on the use of advanced equipment for non-contact measurement of surface microtexture. Using profilometric data, the system analyzes pavement texture and identifies critical areas with either increased or decreased roughness.

On these selected sections, the coefficient of friction is additionally determined, which allows for a significant reduction in the total number of direct measurements without compromising the accuracy or spatial resolution of the results. The proposed technology improves the efficiency of pavement condition monitoring, optimizes diagnostic costs, and enables timely decision-making regarding road maintenance and repair.

Ultimately, this contributes to enhanced traffic safety and prolongs the service life of the pavement, supporting modern road infrastructure management strategies.

Full-Scale Experiment and Numerical Modeling of Beam Bending with Constructional Camber

2025-07-25T19:49:21+00:00

An experimental study was conducted to evaluate the effectiveness of beams with constructional camber. A custom test rig was developed and assembled to carry out full-scale investigations of beam deflection. Beam specimens were fabricated using FDM 3D printing technology from coPET material. Three types of experimental beam specimens were produced: with a straight axis (model beam), and with 100% and 200% camber. The experimental setup simulated the behavior of a two-span beam with fixed ends subjected to a central point load. The deflection under load was measured. Load tests were performed on the experimental beams with an applied force ranging from F = 0 to 200 N in increments of ΔF = 10 N. Diagrams were constructed to show the relationship between the deflection of the model and cambered beams under various loading conditions. A zero-deflection beam effect was observed. To verify the experimental findings, the behavior of the tested beams was also analyzed analytically and numerically. Analytical modeling enabled the adjustment of the elastic modulus to account for the material structure produced by 3D printing. The results obtained from numerical simulations in the LIRA software package showed good agreement with both the experimental and analytical results. Visualization was performed using FUSION software, where colored diagrams illustrated the deflection distribution along the beam length and demonstrated the efficiency of cambered beams in reducing deflections with increasing constructional camber. The research contributes to the study of constructional camber effects. The objective of the study is to develop practical technologies for applying constructional camber in real-world construction. The feasibility of using 3D printing technology for full-scale modeling of structural elements in buildings was demonstrated. A correlation was noted between the mechanical properties of 3D printed structures and the printing mode and filament parameters.

Urban planning tasks and principles of transformation of the planning and transport framework of urbanized territories of eastern Ukraine

2025-07-27T13:57:58+00:00

The article analyzes the principles and tasks related to the transformation of the planning and transport framework of urbanized areas of eastern Ukraine in the context of post-war recovery. The structural consequences of the hostilities are deindustrialization and degradation of settlements, which arose due to a significant outflow of population, destruction of infrastructure and exhaustion of the resource base. The impact of the war on changes in the planning and transport framework of urbanized areas of Luhansk region is investigated. The key factors that will influence the development of the region, including economic, socio-political, demographic and environmental factors, are identified.

An analysis of the transport framework of the Luhansk and Donetsk regions, whose role is crucial for the recovery of the region, is carried out. It is established that current conditions require modernization of existing transport networks, elimination of bottlenecks and adaptation of the system to new realities. The necessity of forming promising transport corridors and implementing strategies based on comprehensive plans for the spatial development of communities is substantiated. The determining factors remain the terrain and the conditions for the formation of a border region with limited transport links to the east.

Prioritization of measures to create sustainable urban development is based on a combination of safety, environmental friendliness, transport accessibility and convenience for the population of communities. Particular emphasis is placed on the reuse of construction waste in the process of road construction and engineering arrangement, which will contribute to the restoration of infrastructure and the creation of development clusters. The conclusions emphasize the need for a systematic approach to the region's recovery, starting with the modernization of the planning and transport framework and the implementation of long-term development strategies. The region's significant potential lies in its planning and transportation framework, developed transport infrastructure, and the availability of convenient industrial sites. A rational strategy for the region's recovery should begin with regional comprehensive spatial development plans. Particular attention should be paid to the modernization of the transport network, taking into account the actual and prospective population of cities, the strategy for the restoration of city-forming enterprises, and regional development schemes.

Research of the road and transport network of the city of Lutsk

2025-07-27T13:57:56+00:00

. This article presents a comprehensive SWOT analysis of Lutsk's road and transport network, aiming to assess its current state, strengths, weaknesses, opportunities, and threats. By evaluating key infrastructure elements, traffic patterns, and policy frameworks, the study provides valuable insights into the development potential and challenges of the city’s transportation system.

The analysis identifies several strengths, including Lutsk’s compact urban layout, a well-connected road system, and recent infrastructure modernization efforts. These aspects contribute to relatively efficient intra-city mobility and accessibility. However, weaknesses such as aging road surfaces, traffic congestion in peak hours, insufficient parking spaces, and a lack of advanced traffic management technologies hinder optimal transport flow.

In terms of opportunities, the article highlights potential investment in smart traffic solutions, expansion of cycling infrastructure, and the development of eco-friendly public transport alternatives. Additionally, increased funding from state and international sources could accelerate the improvement of road conditions and mobility services.

The study also examines external threats, including rising vehicle numbers leading to greater congestion, environmental concerns linked to urban emissions, and economic constraints limiting infrastructure expansion. Addressing these challenges requires strategic planning, policy interventions, and stakeholder cooperation.

By integrating SWOT analysis findings, this research provides recommendations for enhancing Lutsk’s road and transport network, ensuring a more efficient, sustainable, and future-ready mobility system for residents and visitors alike.

The relationship between land surface temperature and land cover characteristics in Lutsk: time series analysis of Landsat satellite indices.

2025-07-27T13:57:55+00:00

Rapid urban population growth exacerbates the urban heat island effect (UHI), which has significant environmental and health implications. Understanding the dynamics of land surface temperature (LST) and its relationship with land cover types is crucial to achieving sustainable urban development. Remote sensing of the Earth is a valuable tool for monitoring and studying the temperature regime of urban areas, as it allows LST information to be acquired over large areas with high spatial and temporal resolution. Unlike traditional weather stations, satellites provide a synoptic overview of an area, which is crucial for studying the spatial patterns of the UHI effect. The Landsat satellites are particularly important as they have provided long-term archival records since the 1980s, and their thermal channels are suitable for calculating LST. They also have channels in the visible, near-infrared and short-wave infrared ranges for studying land cover characteristics. This study analyses the long-term dynamics of the annual average LST values and the NDVI and NDBI spectral indices for Lutsk between 1984 and 2024, using Landsat satellite data (5, 7, 8, and 9) and the Google Earth Engine platform. Time series analysis and linear trend, and correlation analysis methods were applied. Significant annual fluctuations in LST were found, as well as a general trend towards growth (+0.17°C/year). A positive trend in NDVI and a negative trend in albedo were observed. Correlation analysis revealed the anticipated strong negative correlation between LST and albedo. However, the positive correlations of LST with vegetation indices and the weak relationships with built-up/bare land indices warrant further investigation into spatial patterns. The results of the study are important for assessing the microclimate and supporting urban planning decisions.

Use of ash-slag mixtures for the construction of road base layers

2025-07-27T13:57:53+00:00

The article provides information on the volume of formation of ash and slag waste from coal combustion, and the volume of their utilization. This is general information on the volume of formation of ash and slag by-products in foreign practice, and their practical and effective use. In world practice, ash and slag are usually used in the production of building materials, such as concrete, asphalt concrete mixtures, bricks, ceramic tiles, thermal insulation, etc. The involvement of these materials in the technological process of road construction will reduce the negative impact on the environment and expand the resource base of the industry. Ash and slag waste consist of a combination of ash-carryover and fuel slag, which have fundamental differences in their structure.

During the conducted research, an assessment of the deformation characteristics of this technogenic soil was performed depending on the degree of its compaction and humidity. The analysis showed an increase in density by 0.01 units. The compaction coefficient gives an increase in the modulus of elasticity from 6% to 7%, and the modulus of deformation from 2% to almost 5%. The influence of humidity on the deformation parameters of ash-slag mixtures is significant, although somewhat lower than the influence of density. Moreover, at optimal humidity, the value of the modulus of elasticity and deformation is the smallest.

Analysis of the chemical and phase compositions of ash-slag mixtures indicates the similarity of these technogenic soils with natural sandy and clay soils. However, the structure of ash-slag mixtures determines a number of significant features compared to natural soils. Comparison of the magnitude of the modulus of deformation of natural soils and ash-slag mixtures shows that this indicator in technogenic soil is somewhat lower than in sandy soils, but is not inferior to natural clay-dusty soils.

Its suitability as a building material for the construction of base layers of road pavements of highways was assessed.

Implementation of regulatory, sanitary-technical, and landscape-urban planning measures for the restoration of small rivers in the Zaporizhzhia region

2025-07-28T15:22:28+00:00

The article presents key aspects of the implementation of regulatory, sanitary-technical, and landscape and urban planning measures aimed at the restoration of small rivers of the Zaporizhia region. The importance of a comprehensive approach to the rehabilitation of water bodies is emphasized, which includes the development and implementation of appropriate legal and technical mechanisms, the cleaning of riverbeds and coastal areas, as well as the integration of ecosystems into the urban environment.

To prevent pollution of small river waters of Zaporizhia region by surface runoff, it is necessary to create water protection zones, clearly define and fix coastal protective strips on the ground, install appropriate water protection signs on the territories of the water fund, maintain proper sanitary conditions in these zones, and carry out improvement of coastal areas. Modernizing wastewater systems will help reduce pollution levels from both point and diffuse sources, including surface runoff. Effective solutions are proposed for the improvement of adjacent areas, which include functional zoning, the creation of recreational spaces and increasing the ecological sustainability of river basins. In order to optimize the regulation of water flows, an inventory of hydraulic structures on small rivers should be carried out, their owners identified and the legality of their construction verified. Hydropower plants that do not have an owner should be placed on the balance sheet of local governments.

Special attention is paid to the need to develop the basins of small rivers of the Zaporizhia region and to a comprehensive approach to the restoration of aquatic ecosystems, which includes regulatory, methodological, organizational, engineering, and landscape and urban planning measures. It is noted that the implementation of such measures will contribute to improving the quality of the environment, raising the standard of living of the population, and forming a favorable urban space.

Features of working with epoxy resin-modified softwood

2025-07-28T15:22:26+00:00

The article considers the improvement of methods for modifying wood with epoxy resin, presents the results of experimental studies of epoxy resin-modified pine, larch, and spruce wood on compression along the fibers, assesses the impact of this polymer composition on the strength of wood, and analyzes the features of their work. The physical and mechanical properties of untreated wood are variable and depend on many external factors. To stabilize these indicators, wood modification is used in various ways. Modified wood becomes more resistant to aggressive factors and stronger. Methods of its processing include the use of modifiers of various chemical compositions. The advantages of epoxy resin are considered. The purpose of our research is to improve methods for modifying wood with epoxy resin, conduct experimental studies of epoxy resin-modified pine, larch, and spruce wood on compression along the fibers, and assess the impact of this polymer composition on the strength of wood and the features of its work. Methods of wood modification with epoxy resins have been improved. The methodology of experimental field tests of the studied wood species has been presented. The features and nature of the work of modified and unmodified coniferous wood: pine, larch, spruce have been established. New experimental data have been obtained regarding the strength characteristics of epoxy resin-modified wood samples in compression along the fibers. After conducting field experiments, the strength of modified and unmodified coniferous wood under study was determined. Strength of epoxy resin-modified wood samples: pine – 59.1 MPa, larch – 72.0 MPa, spruce – 54.8 MPa. It was established that the strength of wood after modification by the autoclave method increased for pine wood prisms by 1.29 times, larch by 1.21 times, and spruce by 1.36 times.

Analysis of noise protection structures as engineering arrangement of streets and roads and ways to reduce the harmful effects of noise from vehicles

2025-07-28T15:22:24+00:00

The problem of reducing noise pollution from road transport remains one of the most relevant in both large cities and rural areas adjacent to highways. Traditional methods of noise protection - the use of concrete, metal and composite screens - demonstrate high efficiency, but have a number of significant limitations: high cost of production and installation, significant weight of structures, limited adaptability to the landscape, as well as lack of environmental flexibility.

The article considers modern approaches to noise protection on highways and city streets and analyzes the effectiveness of existing noise protection structures and the main measures that can be used for such protection. Based on a systematic approach, the main types of noise protection screens, their design features, materials from which they are made, and possible impact on the environment are characterized. In this work, important attention is paid to the problem of reusing recycled materials, which can be waste of old rubber (in particular, used car tires), polystyrene foam and any other foam materials.

The article proposes the use of a new noise protection screen, the frame of which will be made of wood, and the middle will be filled with various types of waste (rubber, polystyrene foam, pieces of foam waste), which will be filled with mounting foam, which will act as a binder. Such a screen will have high noise-absorbing properties.

This approach allows solving two problems: reducing the noise load on the areas adjacent to highways and city streets, and allowing the disposal of environmentally problematic waste.

The design of a wooden noise barrier is considered as an example of a sustainable engineering solution that combines environmental friendliness, efficiency and economic feasibility. The results of this study can be used in the implementation of construction projects, major repairs and reconstruction of road infrastructure.

Parameters of the group behavior model of drivers on motor roads

2025-07-28T15:22:23+00:00

The analysis of the human-vehicle-road-environment system is an important part of the construction of highways and the further development of international transport corridors between European countries. An important point here is the relationship between the behavior of drivers. It is proposed that the parameters of the model of the group behavior of drivers be considered to assess the socially necessary performance of drivers on highways.

The article "Parameters of the model of the group behavior of drivers" deals with the issue of the dynamics of the calculated characteristics of the traffic flow, namely the actual and socially necessary speeds of movement and their analysis.

The conducted studies of the actual and socially necessary speed of movement on highways allowed the author to assume that the dynamics of the calculated characteristics can be used to judge the laws of the evolution of highways.

An important task of highway design is the long-term forecasting of the calculated characteristics of traffic flows. One of the problems is the problem of forecasting the actual and socially necessary speeds of traffic on highways.

The speed of movement of the “man-car” system in the environment reflects the relationship between the components of the emergency control system, since it is the result of its functioning. Therefore, speed can be considered as a state parameter of a given system. It makes sense to use the probability of transition from the actual to the given speed as the state coordinate.

In the structure of state parameters, the given speed should be considered as normal, i.e., most consistent with the goals and objectives of the functioning of the emergency response system at this stage of its evolution.

State coordinates can be used as weighting coefficients in a motion speed prediction model.

A model of the evolution of a closed-state Human - Vehicle - Road - Environment system can be represented as a system of differential equations reflecting the dynamics of the absolute organization of its components.

With gradual improvement of traffic conditions (phased construction, reconstruction, major repairs), the driver’s individual speed norm tends to the functional speed norm for the purpose of freedom of action. The latter is equal to two-thirds of the design speed of the vehicle.

Experimental studies have confirmed the validity of the formulas for estimating the parameters of the forecasting model.

The model for predicting traffic speeds is adequate for the observed data on the dynamics of design, design and normal speeds for drivers.

It was found that the solution to this problem is possible by analyzing the evolution of the relations between the components of the "man-car-traffic environment" system.