Ways to Improve Construction Efficiency

Effect of nanocatalyst modification on concrete strength

Oleksandra SHYSHKINA — 2025-01-05

The article presents the results of the analysis of the properties of materials based on Portland cement, polyalcohols and surfactants used in ultra-low doses, describes the results of determining the effect of ultra-low doses of glycerin and surfactants on the strength of concrete. The aim of the work is to determine the effectiveness of the use of a mixture of glycerin and surfactants in ultra-low doses during the hardening of Portland cement. The methodology of the experiments includes the following methods: analysis of studies on the use of glycerin and surfactants; standard concrete test methods; comparative analysis; systematization and generalization of foreign and domestic experience. As a result of the study, the effect of a mixture of glycerin and surfactants applied in ultra-low doses to the strength of concrete. It has been proven that in this case, the action of ultra-small doses of a mixture of glycerin and surfactants is to reduce the number of open pores in the cement stone. Experimental studies have confirmed that surfactant molecules such as hyperplasticizers or others significantly alter the pH of the water used to make concrete. Increasing the mechanical strength of the resulting concrete makes it possible to replace part of the cement with a nanopowder made of a cheaper mineral. It has been found that an increase in the water-cement ratio in a mixture of glycerol and surfactants leads to an increase in the efficiency of ultra-low doses of surfactants substances in the formation of concrete compressive strength. The highlighted scientific materials became the starting point for understanding the issue under study. The effect of ultra-low doses of glycerin and surfactants on the strength of concrete has been identified and substantiated. The results of the study can be used in the production of concrete and reinforced concrete products and structures.

Study of viscous-britle fractures of experimental pipes of different manufacturing technologies during natural tests

Valeriy MAKARENKO — 2025-01-05

A method based on the principles of acoustic emission has been developed and tested to determine the rate of crack propagation in pipes during field (full-scale) tests while comparing the results obtained on full-thickness DWTT samples. The mechanism of viscous-brittle fracture of pipes of different strength and viscosity classes was established. The principles of increasing the resistance of pipe metal to fracture are determined. The steels of controlled rolling and progressive heat treatment with the use of accelerated (spray) cooling were studied. Recommendations for extending the operational (trouble-free) life of long-duration gas pipelines are given.

It is known that as the elastic energy reserve increases, the working conditions of the metal in the structure become more difficult, the fracture resistance decreases, and the critical crack length capable of spontaneous development and the stress intensity factor decrease. At the moment of crack formation in the pipe metal, the stored elastic energy is almost instantly transferred to the fracture zone and contributes to its propagation. In addition, in addition to the energy stored by the compressed gas, the energy of elastic deformation of the metal is also stored in the pipeline. Such elastic energy stored in the pipe metal is determined by the combined effects of annular and longitudinal stresses according to the formula E = 5/32 (p² D² S)/Eh, where p – pressure in the pipe; D – pipe diameter; S – pipe surface; h – pipe wall thickness; E – modulus of elasticity of the metal. The above formula shows that the value of the elastic deformation energy stored by the metal is determined by the operating parameters of the pipeline. For example, for a gas pipeline with a diameter of 1420 mm and a working pressure of 7,5 MPa, the specific elastic energy in a 14 mm thick pipe wall is 2 MJm² , and for a pipeline with a diameter of 1020 mm with the same wall thickness and a working pressure of 5,5 MPa – only 0,4 MJm² . It should be noted that an increase in the elastic energy of the metal in the structure contributes to the localization of the deformation in the defect and its accelerated development.

In main pipelines, where a wide range of steels is used and there is a high probability of concentrators, an increased elastic energy reserve contributes to a decrease in metal performance. Therefore, it is necessary to clearly understand the mechanism of influence of the elastic energy reserve in the pipeline metal on its performance. The negative impact of the energy stored in the metal of the pipe on the operation of gas and oil pipelines is manifested in their numerous destructions with severe economic and environmental consequences, which encourages scientists to further study this problem.

Recycling of construction materials in Ukraine: legislation, current state, issues, and future prospects for the market of reusing damaged structures

Olena MURASOVA — 2025-01-05

In today's world, the issue of waste recycling and disposal has reached a large scale. With the continuous development of major cities, construction waste constitutes a significant portion of all waste generated by global economies. Dismantling, recycling, and reusing construction materials is known as recycling, which is a widely recognized concept in developed countries.

In Ukraine, where the construction sector was one of the key economic sectors even before the onset of the large-scale aggression by the Russian Federation, the issue of recycling is particularly relevant. Furthermore, since the outbreak of military actions in 2022, the volume of construction waste has significantly increased due to the large number of destroyed buildings and infrastructure facilities. This has led to additional environmental challenges, issues regarding efficient resource use, and the collection and recycling of waste. According to various estimates, up to 30% of all waste is attributed to that generated as a result of military actions.

Globally, recycling construction waste is a highly profitable industry. Leading countries have established markets for companies operating in this sector. In most European countries, the level of recycling is quite high. For instance, in the Netherlands, about 90% of construction waste is reused, followed by Belgium at 87%, Denmark at 81%, the United Kingdom at 45%, Finland at 43%, and Austria at 41%.

Currently, Ukraine lacks a market for the reuse of construction waste, which negatively impacts the environment and complicates the effective use of secondary materials. The aim of this research is to analyze the existing situation in the recycling sector in Ukraine, taking into account the specific challenges posed by military actions, and to develop recommendations for improving the management system for construction waste.

In the context of global challenges related to climate change and sustainable development, the study of recycling construction materials in Ukraine becomes particularly significant. Developing effective technologies and implementing innovative solutions could be a key factor in restoring damaged infrastructure and reducing negative environmental impacts.

Stability of the shell of the minimum surface on a rectangular plan, taking into account geometric nonlinearity under thermal and power loading

Оleksandr KOSHEVIY — 2025-01-05

When developing the classical theory of minimal surface shells, scientists focused on methods that require maximum simplification of the solving equations and elimination of values that do not significantly affect the final results. This reduces the class of minimal surface shells that are studied and excludes some important mechanical and physical effects from view.

With the development of computational complexes, new problems of the theory of shells arise, which must be solved without the involvement of auxiliary hypotheses about the nature of the desired fields along the thickness of the shells of minimal surfaces. This leads to the development of non-classical shell theories, which are classified on the basis of the connection of different methods of constructing systems of equilibrium equations of shell mechanics with methods of boundary value problems of elasticity theory.

When designing minimum surface shells, one has to deal with calculations for the stability of minimum surface shells on different contours, taking into account geometric nonlinearity. Having a small structural mass, a thin-walled spatial shell is an exceptionally rigid structural form.

Geometrically nonlinear problems are those in the theory of elasticity that take into account nonlinearity in the dependence of strains and displacements, while stresses and strains are related linearly. Taking into account nonlinear components of deformations is necessary for the calculation of flexible thin-walled structures.

In general, solving a nonlinear system is reduced to solving a sequence of linear systems. Note that only the right-hand side of the system of equations changes during successive iterations, which allows the stiffness matrix to be factorized only once.

For the first time, a numerical study of a minimum surface shell on a rectangular plan with geometric nonlinearity was performed using the finite element method (FEM), the reliability of the results was verified against theoretical values, the convergence of the finite elements was high, and the dimensions of the finite elements were chosen to be optimal in number and size. The geometric nonlinearity shows a 9% improvement in the actual stresses and displacements from the linear calculation, which is a good material saving and calculation accuracy.

Analysis of technologies for restoring the serviceability of reinforced concrete ceiling structures

Oleksandr MOLODID — 2025-01-05

As a result of military operations, a significant part of construction objects was damaged by off-design impacts. Among the damaged structures, a significant proportion is accounted for ceiling. In our case, majority of ceilings are made of hollow-core reinforced concrete slabs. According to the current regulatory documents, some of these ceilings are subject to restoration. Therefore, the analysis and identification of the most rational and effective technologies for restoring the operational suitability of damaged building structures, in particular, ceilings, is an urgent task today. The article analyzes the known classical and new technologies for repairing and strengthening reinforced concrete slabs, including: dismantling damaged slab and following production of the plate in-place; applying cement-based repair mortars; repairing with epoxy materials; strengthening structures with carbon or basalt materials; classical technologies (bringing metal unloading beams from above (below), installing double-cantilever unloading beams, installing tie bars, creating indistinguishability of beams, building up the beams, etc.). The advantages and disadvantages of each of the technologies, both structural and technological, were identified. The analysis shows that the existing methods are aimed either at repairing damage or at strengthening defect-free structures. Therefore, the development of new or improvement of known technologies for the comprehensive restoration of hollow core slabs is an urgent task. However, taking into account the types of damage to hollow-core slabs as a result of off-design impacts, a new or improved technology for their comprehensive restoration is currently needed. At the same time, such a technology should be structurally and technologically reasoned.

Rational constructive solution of protective structures of covering trusses under dynamic loads

Artem BILYK — 2025-01-05

The article presents the results of studies on the search for rational parameters of protective structures of small-span roof trusses under dynamic loads. The main properties of such structures, the requirements they must meet, and the adopted provisions are considered. The main principles of designing protective structures of steel structure roofs are formulated to ensure the required strength and stability of the structure under impulse loads. The aim of the work is to develop a methodology for alternative design to determine the rational (limitedly optimal) height of a steel truss roof with a cross lattice under short-term impulse loads. For the selected type of structure with known general parameters of the structure, the main technical solutions are adopted in alternative design. According to the refined classification, the technical and economic criteria for comparing alternatives are described by various functions: static, dynamic, convex non-convex, polymodal, nonlinear, discrete, discontinuous, undifferentiated and partially separable. The search for a global optimum of such target functions for a generalized problem of optimal design of a spatial structural system using existing analytical methods has certain difficulties. This is due to the fact that various design solutions with different topology, different calculation schemes and a discrete set of geometric characteristics of element sections cannot be reduced to the description of a single system of functional dependencies, since private criteria of parameters of individual equations depend on different variables. It is known that in a weakly structured problem, parametric dependencies between ascending and variable parameters are described not only by explicit analytical expressions, but also by discrete mathematics methods based on predicate calculation, and the functions of private comparison criteria are algorithmic. For the variant design and determination of the rational height of the steel truss, a beam analogy is used. As a calculation scheme, a calculation scheme of an ideal I-beam is adopted taking into account the shear deformation of the cross section. Shear deformations of the section take into account the increase in deflections of the beam-rod steel truss relative to the I-beam. The target function of steel consumption is recorded depending on the height and purlin of the steel roof truss, the dynamic factor is also taken into account. Analytical dependencies for determining the height of trusses are obtained, taking into account their dynamic characteristics with additional load from the action of a blast wave at the end of the roof block. The target criterion is the mass of structures, which allows us to move on to cost indicators.

Analysis of technologies for repairing cracks in stone structures

Oleksandr MOLODID — 2025-01-05

In the process of technical inspections of buildings and structures, including those damaged as a result of military operations, it was found that the main damages of stone structures are cracks of different spatial position, width of opening, depth and length. Cracks can be caused by many different factors, such as subsidence of the base, for example, due to systematic wetting as a result of damage to the drainage system, mechanical stress, temperature, humidity and weathering, etc. In recent years, a significant number of buildings and structures in Ukraine have been subjected to off-design impacts, namely explosions. In this regard, as well as taking into account other factors, there is a need to find the optimal technology for repairing cracks in stone structures, which will not only fill the crack and restore the integrity of the structures, but also improve the performance of the restored structures, provide spatial stiffness if necessary, and at the same time be relatively simple to perform and have a relatively low cost of work. According to DSTU B B.3.1-2:2016, the main technologies for repairing structures with cracks include crack injection, introduction of reinforcement elements and full or partial replacement of masonry. The article discusses the most well-known repair technologies and outlines their advantages and disadvantages. The most commonly used technology is crack patching with repair mortars. However, this technology is effective only in the case of guaranteed stabilisation of crack formation. The classical technologies for repairing and strengthening structures include crack injection with repair solutions, the installation of cages (mortar, reinforced concrete, steel, combined) and ‘stitching’ cracks by installing steel elements (plates, rods, channels, etc.). A new direction in the reinforcement of structures is the ‘stitching’ of cracks with high-strength steel rods by inserting them into the body of structures using a ‘dry’ or ‘wet’ method and external reinforcement of structures with cracks using high-strength carbon reinforcement elements (fibres, fabrics, lamellas).

Use of advantages of pulling method for erection of large-span coatings

Oleksandr IGNATENKO — 2025-01-05

Based on analysis of the features of the known variant of lifting of large-span coatings through the pulling method, a new technological solution for erecting coatings using lifting modules was developed. According to the developed solution, first, by methods of free lifting using self-propelled boom cranes, paired columns of the frame, inter-column beams and bundles are mounted. Guide profiles are fixed on inner surfaces of paired columns. Lifting modules are mounted between paired columns on foundations. Support frames are fixed on upper platforms of lifting modules. The large-span block of coatings is enlarged on mounting stands provided that bearing crossbars of covering rest on support frames. The moving of coating girders to design height is performed by pushing method. In the process of vertical movement of the load from the crossbars of the coating, the lower and upper platforms of the lifting module are alternately perceived, which interact with the guide profiles. After moving the roof girders to the design mark, support frames are fixed between the heads of paired columns. Unloaded lifting modules are moved to foundations using guide profiles and dismantled. The use of the developed structural and technological solution allows to reduce the volume of top-climbing labor-intensive dangerous installation work before the operations for the final fastening of the crossbars of the supporting frames of the coating between the heads of the paired columns of the frame. All components of the process of moving the coating from the foundation level to the design height using a lifting module are automated. Also, the developed solution can significantly reduce the overall time for the construction of coatings. All installation work on the enlargement of coatings on stands using self-propelled boom cranes and a set of works on the vertical movement of coatings using lifting modules are carried out on the sites, dimensions of which do not exceed overall dimensions of large-span erected coatings.

Review of designs of machines for surface compaction of products made of construction mixtures

Kostiantyn POCHKA — 2025-01-05

Concrete works are the most important in construction by scope and cost. Concrete as a building material serves as the basis for creating load-bearing structures of buildings and constructions. This is justified by its high mechanical characteristics and processability. Almost any construction elements of structures of any configuration and purpose can be made of concrete. This research conducted a comprehensive analysis of surface-acting molding equipment of construction industry plants – vibrating and non-vibrating.

The surface-acting molding equipment using vibratory action on the mixture to be compacted is considered. Examples of such installations are locally developed and self-propelled plates of foreign companies Dynapas and Amman. The use of pendulum vibration exciters in autonomous vibrating compactors makes it possible to obtain directional vibrations. The versatility of Amman vibrating plates is ensured by changing the direction of the vibration speed, used for trenches and large areas, and has a working width adjustment. ZENIT-TECHNO is also engaged in the production of equipment for the concrete industry, which presents a wide range of equipment for the production of concrete mixtures – lines for the production of concrete products by vibration under pressure, molds for any products, installations for processing concrete products, equipment and tools for laying paving stones, slabs, curbs, and various clamps.

Despite the continuous improvement of vibratory concrete forming units, it is still impossible to get rid of the increased noise and vibration levels at workplaces, which creates harmful working conditions. Non-vibration forming methods not only eliminate the disadvantages of vibration technology, but also open up new opportunities to increase labor productivity and reduce the metal consumption of equipment. One of the methods of non-vibration molding is roller pressing, which is characterized by the fact that new portions of the mixture are repeatedly pressed into the freshly laid layer under the roller, which reciprocates across the mold. Extrusion pressing involves pushing the raw material mass through a hole in the die with a screw.

The analysis of existing technical and economical information, experience of industrial and laboratory researches suggests that the calculation, design and creation of new concrete forming units are relevant and promising at the present stage of their use.

Monitoring of indicators and criteria for assessing energy consumption by residential buildings

Ivan PEREGINETS — 2025-01-05

The scientific article reveals the role of monitoring energy consumption by residential real estate objects throughout the life cycle, which is an integral part of increasing energy efficiency. An analysis of the existing methodology for assessing the energy efficiency of real estate construction has been conducted.

Promising concepts of methods for assessing indicators and criteria for the energy needs of buildings while ensuring comfortable conditions for people to stay in them have been investigated. Studies indicate that the use of a system for continuous monitoring of energy consumption indicators according to energy efficiency criteria provides significant resource savings with a reduction in maintenance costs and operating costs. The prospects for implementing monitoring of energy efficiency indicators are substantiated. The feasibility of an integrated approach to monitoring indicators and criteria for assessing energy consumption, including all stages of the life cycle of buildings and structures, has been proven. The methodology proposed by the author of the article can be applied by an individual energy manager and energy management departments of municipal enterprises, managers of multi-apartment residential buildings.

Considerable attention in energy management work is paid to the collection and analysis of data on the consumption of fuel and energy resources in buildings and structures of the municipal and budgetary sphere, including dormitories of educational institutions of various degrees of accreditation.

At the same time, investors and managers of residential buildings have the opportunity to ensure: correct operation of equipment; creation of an archive of energy consumption data; identification of methods and means for the greatest increase in energy efficiency potential.

The article discloses the use of the "ET-diagram" and "ET-curve" as basic components of monitoring indicators and criteria for assessing energy consumption by residential buildings.

Weekly energy monitoring is recommended for timely detection of unforeseen PER costs and elimination of possible malfunctions. The application of the methodology presented in the article is appropriate for both individual residential buildings and complexes of buildings, blocks, neighborhoods and cottage towns with a centralized PER supply system. Based on the research results, the main principles of monitoring energy consumption indicators have been determined, which contribute to increasing the financial and economic indicators of facilities. The proposed approach to organizing monitoring indicators and criteria for assessing energy consumption by residential buildings allows for a thorough analysis of resource consumption and forecasting the volumes of their use for the future, including the use of BIM technologies.

On the technology of construction of semi-closed greenhouses of the fifth generation

Taras CHEBANOV — 2025-01-05

The directions and trends of development of protected ground structures at the present stage are robotic greenhouses, nanotechnology, interactive environment, sensor and LED systems, development of cannabis growing technologies, etc. The development of the above directions is facilitated by the fact that large greenhouse complexes have exhausted their resource for further technological and technical development. Such an organization of greenhouse production suffers from large energy and financial losses and poses a serious problem for the environment. The possibilities of vertical greenhouses have been experimentally studied, as well as one of the elements of the pyramid greenhouse – multi-tiered narrow-rack hydroponics. Theoretical studies of sixth-generation greenhouses are being conducted – advanced technological and engineering systems of fully closed greenhouses. Or those in which regulation and changes in microclimate parameters occur using the reserves of the greenhouse's internal space. Without the involvement of external factors.

One of the shortcomings of modern greenhouses is the inability to maintain an optimal and high-quality microclimate at certain times of the year. The design and technological features of modern glazed greenhouses of the fifth generation of semi-closed type are considered. Semi-closed type greenhouses allow to ensure high requirements for the microclimate in greenhouses and, accordingly, high yields with lower costs of material resources. A special system regulates humidity in such a way that energy consumption becomes minimal. Even with a strong decrease in the outside air temperature. The system has two fans: supply – air that supplies from the outside to the inside and exhaust, which extracts warm moist air from the greenhouse. The schematic diagrams and calculations of physical processes during the construction and operation of such greenhouses are presented. Ensuring high design requirements for the microclimate in greenhouses (temperature and humidity, carbon dioxide level, air exchange rate - is especially relevant when growing medical cannabis.

KNUСA has been conducting research on the technology and mechanization of greenhouse construction for a long time. Special attention is paid to the development of technology for installing frames of such structures, especially light metal greenhouse structures. Technologies are protected by Ukrainian patents for invention.

Study of the effect of organic shell on the leaching of protective compositions from wood protected from fire

Yuriy TSAPKO — 2025-01-05

Today, there are various ways to fireproof wood. When wood is moistened, flame-retardants dissolve in a humid environment and gradually wash out to the surface, after which the fire protection effect decreases over time. Acid-based products do not have a significant leaching problem due to changes in wood moisture, but by penetrating deep into the wood structure and interacting with cellulose, they reduce strength characteristics. Another method is to apply a coating based on organic or inorganic binders to the wood surface. Products based on organic binders have increased smoke generation and toxic substances, so their use is dangerous. Therefore, an analysis of protective materials for wooden building structures was carried out and the need to develop reliable methods for studying the leaching of flame-retardants necessary for the creation of new types of fire protection materials was established. There is a need to determine the conditions for the formation of a barrier to the leaching of flame-retardants and to establish a mechanism for inhibiting the transfer of moisture to the material. In this regard, a mathematical model of the process of leaching protective substances from wood after its impregnation with flame-retardants when using a polymeric shell made of organic material as a coating was developed, which allows us to evaluate the effectiveness of the polymeric shell by the amount of water absorbed. The results of calculating the weight gain of the sample during exposure to water indicate an ambiguous effect of the nature of the protection on water absorption. In particular, this implies the availability of data sufficient for the qualitative process of inhibiting moisture diffusion and identifying, on its basis, the time point from which the decrease in coating efficiency begins. Thus, there is reason to believe that it is possible to regulate the processes of wood protection in a targeted manner by using polymer coatings that can form a protective layer on the surface of the material that inhibits the rate of water absorption.

Problems of choosing column foundation structures according to labor consumption and productivity of their arrangement

Kateryna NOSACH — 2025-01-05

Reinforced concrete frame structures are often used in construction practice due to a successful combination of the characteristics of the cost and duration of construction work, as well as the versatility of the purpose of ready-made buildings. The construction industry strives to combine such areas of development as speeding up building construction, reducing labor-intensive processes and lowering the cost of work and materials - without losing the quality characteristics of the finished building. In order to achieve the listed properties, the development and invention of new equipment, materials and structural and technological solutions is taking place. The construction of columnar foundations takes about 15-20% of the time resource, so there is a need to find solutions that can speed up the processes and make them cheaper.

The modern level of development of the construction industry allows the use of various structures and equipment, as well as combining technological solutions for the arrangement of structures and individual elements, in particular columnar foundations. A popular solution is the installation of prefabricated monolithic foundations, which, in its finished form, should combine the advantages of prefabricated and monolithic technologies. The possibility of combining modern solutions and technologies requires research to determine the expediency and effectiveness of constructive solutions, as well as to determine the algorithm of actions. The question arises about the prospects of modern methods. This article provides an overview of the existing solutions that can be used for the installation of prefabricated monolithic foundations, taking into account the structural requirements in accordance with current regulations. The main advantages and disadvantages of each of the solutions, as well as the conditions of application, are determined. Methods of using modern prefabricated structures, equipment, as well as the combination of technology of prefabricated monolithic foundations are considered in order to find options that meet the needs. It was determined that there is not enough analytical and empirical data regarding the effectiveness of the adopted decisions in interaction with the rest of the factors, such as structural and technological solutions of the remaining elements of the building, volume-planning solutions, conditions of the construction site, environmental conditions.

Theoretical basis of resource provision in unstable conditions for an investment and construction project at the design stage

Oleksandr DUBYNKA — 2025-01-05

The article defines the theoretical foundations of resource provision in unstable conditions for an investment and construction project at the design stage.

The features and conditions of the functioning of investment and construction activities, its environment is very complex, unpredictable, changeable, which complicates the successful conduct of activities, and investment and construction activities are also subject to high risks, such as, first of all, large cost overruns, construction delays, increased construction duration and non-compliance with the required quality of construction products. If such a problem is not taken into account, it can turn into very bad consequences, both for the developer's company and for future owners of construction sites.

Having considered the complex environment of construction projects and the opinions of various scientists, it can be noted that the analysis and assessment of similar or related projects at the pre-investment stage of investment and construction activities can help avoid many negative impacts of the origin of unstable conditions or uncertainty on the result of this activity. At the stage of forming an investment plan and developing a construction project, the most important thing is to take into account factors that could, in the event of destabilizing situations, have a negative impact on the effective and successful process of implementing construction projects as a whole.

In order to provide potential investors with the opportunity to reliably invest their financial resources in a construction project, a pre-investment selection tool was considered, taking into account the factors of unstable conditions, achieving the prevention of the risk of a probable increase in the actual cost and construction terms at the design stage. The considered theoretical and practical results of the presented material can be used to solve practical problems of planning investment and construction activities.

Theoretical and applied tools using for optimization investment and construction projects

Aleksei TUGAY — 2025-01-05

The article provides for the possibility of using theoretical and applied tools for optimization of investment and construction projects.

The use of innovative methods through an engineering approach to the organization of construction consists in accumulating the results of scientific achievements, knowledge, careful study of external factors in order to find new ideas, new technologies and tools, which should contribute to obtaining better results in the implementation of construction projects throughout their entire life cycle, and also minimize risks for the investor. The analysis conducted allowed to identify the need for improving methods for assessing the reliability and optimizing the successful implementation of construction projects. This is especially relevant in conditions when increasing the efficiency of capital investments in construction projects requires improving economic relations in construction, strengthening contractual discipline, increasing the economic responsibility of builders and customers for the final results.

For the effective use, in the current economic conditions, of existing methods of construction planning and production organization, for a positive impact on the acceleration and efficiency of construction, it is necessary to include in these methods the consideration of the existing specific features of the construction industry. The options for the possible application of organizational and technological tools are considered, the results of the presented material can be used to solve practical problems of optimizing and improving project indicators in planning and managing investment and construction activity processes.

A professional approach to the tool for effectively solving the problems of developing construction production with optimal distribution of investments is an obvious necessity today. The need to create methods for solving problems related to increasing the efficiency of construction project implementation, minimizing project execution time, and maximizing profits, taking into account organizational, technological, economic factors and elements of the external environment, determines the relevance of this work.

Use of the recycled aggregates – a way to the sustainable rebuild

Oleksandr KOVALCHUK — 2025-01-05

The question of wide use of recycled aggregate on the basis of demolition wastes rises sharp due to the different points of view: from the point of view of necessarity to utilize multitoned wastes appeared because of war influence, from the point of view of strong will to rebuild the country and also because of the need to have economical, ecological and natural sources rational consumption.

In the same time, such recycled products could also have high defective structure because of their origin and demanding to implement the special technology of their treatment and use. Peculiarities of Ukrainian national experience for such systems if their composition. Namely possible presence of organic compounds and products of war activities, that leads to some difficulties in structure formation in concretes on their basis.

As a potential method to decrease defective structure appearance in concrete is introduction of modifying admixtures, promoting self-healing of the structure elements in concrete, and also use of alternative cements, able to resist against high structure movement, appeared due to the presence of organic additives. Also, use of alternative cements makes it possible to widen raw materials base for rebuilding of Ukraine, so far as present source even taking into account perspective production of 20 million tons of the cement with the need more than 30 million tons per year is not enough.

The implementation of the results of this study will not only solve the issue of recycling large-scale industrial waste, but also significantly increase the pace of construction and restoration of infrastructure, damaged and destroyed housing stock by obtaining a large raw material resource in the form of secondary recycled aggregate as a local raw material. It will also be possible to expand the use of alkaline binders in construction production and increase the use of technogenic waste, represented by concrete buildings and structures that require immediate and complete recycling.

Based on the results of the work, recipes for concrete mixtures using recycled aggregates and methodological foundations for regulating the self-healing processes of the structure of such material will be developed.

Organizational aspects of digital transformation of construction processes

Denis DUBININ — 2025-01-05

The article examines the organizational aspects of the digital transformation of construction processes, which is a relevant issue for increasing the efficiency and competitiveness of the construction industry, analyzes current trends in the implementation of digital technologies in construction, their impact on project management, cost optimization, risk reduction and improvement of the quality of construction work.Particular attention is paid to organizational challenges that arise during the implementation of digital solutions. Among them, the need to change management approaches, adapt corporate culture, train personnel with appropriate digital competencies, as well as integrate new technologies into existing organizational and technological processes, as well as construction administration and management processes, is highlighted, it is emphasized that digital transformation encompasses not only the implementation of information technologies, but also requires a strategic approach to change management at the level of individual construction participants.The use of BIM (Building Information Modeling), IoT (Internet of Things), process automation, digital platforms for project management and cloud services is also considered. The advantages of using these tools are analyzed, in particular, increasing transparency and speed of communication between project participants, accuracy of design calculations and reduction of waste in construction.Practical recommendations are provided for the formation of an effective digital transformation strategy for construction companies. The main stages are proposed: assessing the readiness of construction participants for change, determining priority areas of automation, developing a roadmap for the implementation of digital technologies and monitoring results. The importance of an interdisciplinary approach is emphasized, which includes close cooperation between managers, engineers, IT specialists and estimators. It is noted that successful digitalization is possible only with support from management, involvement of employees in the change process and investment in modern software and technical equipment.

Problems of ensuring accuracy installation of building frames

Liubov LEPSKA — 2025-01-05

Analysis of the current level of development of the construction industry and trends in the development of technology for the construction of frame buildings for industrial and civil purposes showed the widespread use of frames of one to four floors for commercial, entertainment, office buildings, which determined the list of representative objects for research. These buildings are characterized by high quality of materials and structures used, while the accuracy of assembly has a significant impact on the efficiency of construction, which necessitated the study of the problem of substantiation and achievement of accuracy parameters for the assembly of building frames.

From the analysis of the butt joints of prefabricated structures of frame low-rise buildings and the problems of ensuring the accuracy of their installation, it was established that the use of modern butt joints of frame structures allows to significantly increase the efficiency of construction, to improve the quality of buildings, but there are unresolved problems with the formation of sets of assembly equipment for the implementation of assembly methods with restrictions on structures in space and forced methods of landing and fixing structures on supports.

The problem of increasing the accuracy of the installation of structures of buildings and structures is considered. The proposed solution to the problem is to improve the installation equipment and the technology of orientation and fixation of structures during their installation. For the automation of the processes of installation of structures, bolted and anchor connections are taken as the main ones as the most technological, which open up the possibility of using semi-automatic devices.

The concept of the technological system of frame low-rise residential construction as a holistic, open, organized, adaptive structure of heterogeneous components is substantiated from the standpoint of a general system approach. This allowed us to determine the level of autonomy of the system, its organizational structure and functions, measures to improve adaptability, and an optimization strategy.

Features of determining the directions of building technological equipment development

Volodymyr RASHKIVSKYI — 2025-01-05

The article describes the peculiarities of determining the directions of development of construction technological equipment used in the construction of frame buildings with prefabricated and monolithic frames.

The results can be used in the organization of mechanized areas on construction sites during the reconstruction, restoration of buildings or during their new construction.

The authors established the order of grouping the thematic areas of research, belonging to geographical zones and the dynamics of development from 2010 to 2024. The dynamics of patenting, searches for mechanized equipment, which is intended to accompany the technological processes of the construction of buildings with a prefabricated and monolithic frame, have been determined. This approach to research allows you to get a picture of the development of the subject based on generalized indicators and to narrow your search interests taking into account the specifics of the research, geographical interest, and the state of development of the research objects.

In the publication, the authors present a research methodology for the development of structural and technological solutions for the mechanization of support for construction assembly processes. The relevance of the direction of development of mechanized technological modules, in particular, universal lifting modules, mobile technological modules for monolithic works is determined. Analytical studies of new structural and technological solutions for the mechanization of construction processes must be carried out in several stages: determination of thematic areas of research, specification of geographical time frames, determination of hidden implicit terms and requests describing the specifics of work performance, design features of technological equipment, their components, functional purpose, etc. The proposed methodology is based on the use of modern search databases, the use of artificial intelligence in the analysis and structuring of search results, and allows for the formation of approaches to the improvement of construction technologies for the construction of prefabricated and monolithic frame buildings.

The defined approaches to the development of construction technological equipment allow making informed decisions to ensure the required technological level of mechanization of construction processes.

Developer as an agent of innovative transformation of construction participants

Oksana HALUNKA — 2025-01-05

Developers, who play a key role in financing, designing and implementing a project, play a key role in promoting innovation throughout the construction value chain. Researching the role of the developer as a catalyst for innovative development among construction participants and researching methods for assessing the innovative development of construction participants in accordance with the developer’s strategic requirements are relevant tasks of construction economics.Developers influence the innovation trajectory by setting performance benchmarks, ensuring compliance with state-of-the-art standards and facilitating collaboration between stakeholders, including architects, engineers, contractors and suppliers.The main focus of this study is the dual role of the developer as a demand generator and innovation driver. On the demand side, developers are setting clear innovation goals, driven by competitive pressures, regulatory requirements and market trends. On the supply side, they are driving innovation through investments in research and development, technology adoption and capacity building initiatives for construction stakeholders.To assess the impact of developers on the innovation development of construction stakeholders, the paper presents a comprehensive assessment framework. The assessment framework uses a combination of qualitative and quantitative methods, including surveys, performance audits and case studies. Specific criteria are established to measure how effectively developers are influencing innovation, with a focus on adaptability, scalability and long-term impact. Case studies of successful projects led by innovation-focused developers are presented to illustrate best practices and lessons learned. These examples highlight how developers can shape the ecosystem of construction stakeholders by aligning incentives, fostering a culture of experimentation and using their position to ensure compliance with industry standards.This study contributes to the understanding of the strategic importance of the developer in driving innovation in the construction industry and provides a practical roadmap for evaluating and promoting innovative methods aligned with the developer’s requirements. The results are expected to be useful for decision-making among developers, policymakers and industry practitioners, ultimately contributing to the development of a more sustainable and forward-looking construction sector.

Analysis of the ukrainian construction market and raider captures in the context of economic security and social responsibility

Anton MOHOLIVETS — 2025-01-05

The article provides a comprehensive multi-faceted analysis of Ukrainian construction in the context of economic security of participants in investment and construction projects and social responsibility. Particular attention is paid to studying the impact of raider seizures on individual enterprises in the construction sector, participants in investment and construction projects and the construction industry itself. It is determined that raider seizures of enterprises and individual buildings are one of the most threatening phenomena for the stability of the business environment and the investment attractiveness of the sector, which in the pre-war period significantly affected the development of the construction sector and the stable work of construction participants. The paper examines key factors contributing to the emergence of raiding, including shortcomings in the legislative framework, corruption, insufficient efficiency of law enforcement agencies, and a low level of legal culture in society.The authors analyze current trends in the Ukrainian construction market, including its dynamics, major players, investment volumes, and regional specifics. The article focuses on critical problems, such as uneven development of regions, risks for small and medium-sized enterprises, and the impact of martial law and the country's post-war reconstruction on the development of the construction industry.The study assumes the role of social responsibility in construction, in particular the need to comply with ethical norms, environmental standards, and take into account the needs of communities during the implementation of construction projects. Separately, the issues of state regulation of the industry, reforming the economic relations of property owners, including land plots, protecting the rights of property owners and tenants, and the necessary creation of mechanisms to prevent raiding attacks are highlighted.The conclusions of the article present recommendations for increasing the economic security of the construction market of Ukraine, in particular by improving legislation, implementing transparent management mechanisms, strengthening cooperation between the state, business and civil society, as well as stimulating socially responsible practices.

Using the chinese experience of accreditation of development companies and construction objects in state housing programs of reconstruction of Ukraine as an example of the "eOselya" program.

Yevgen ZELTSER — 2025-01-05

The need to provide housing for the citizens of Ukraine has become acute since Ukraine gained independence. The amounts of funds allocated by the state for housing construction and financing of state housing programs are extremely insufficient. Thus, according to the new state housing program "eOselya" in Diya, the operator of which is PJSC "UKRFINZHYTLO", in total, in 2022-2024, only 14.4 thousand families received an affordable mortgage and purchased their own housing at the expense of issued mortgage loans in the amount of UAH 23.3 billion.

Since the beginning of hostilities, this problem has become even more urgent. As of January 2024 the total amount of only documented losses in residential and non-residential real estate, as well as other infrastructure of Ukraine is more than $135 billion. In total, as a result of hostilities, more than 203,000 high-rise buildings and private houses were destroyed or damaged. As a result, the main expenses in the housing sector are related to additional expenses of citizens for renting housing and reached $15.4 billion.

Considering the fact that "eOselya" is one of the key tools for stimulating housing construction and the work of the construction market of Ukraine in general, the main emphasis in the program is on the primary market, the activation of housing construction, which in turn will stimulate the development of related industries. That is why it is urgent to solve all problematic issues that prevent the involvement of as many development companies as possible to participate in the program. One of these issues is the need for the partner banks of UKRFINZHYTLO to improve the accreditation procedure for development companies and construction projects.

Therefore, it is clear that at the present time, state policy measures aimed at the development and reform of state housing programs, which must take into account the existing global experience of providing citizens with housing, are becoming particularly relevant. It is proposed to study China's experience in state regulation of the real estate market and ways of its use in Ukraine, in particular in matters of accreditation procedure for development companies and construction projects in state housing programs.

A comprehensive solution to the problematic issue of accreditation procedure for development companies and construction projects by partner banks, taking into account the existing Chinese experience, will contribute to the involvement of as many high-quality, stably working development companies as possible to participate in state housing programs, in particular the "eOselya" program. This will make a significant contribution to the successful reform of state housing programs in Ukraine in the context of the country's reconstruction during and after the end of the full-scale war with russia.

Peculiarities of Conducting and Taxing the Business of Sole Proprietors (SPs)

Halyna HAMAN — 2025-01-05

The article examines the peculiarities of conducting business and taxation of sole proprietors (SPs) taking into account modern realities and further prospects of their effective activity. The opening of a record number of SPs for Ukraine, despite the war, is a manifestation of the stability of domestic business, in which a significant place is given to the role of women. The authors determined that the features of the organization of creation, management and closure of SPs in Ukraine include: quick registration through Diya; restriction of activity under certain types of NACE codes (gaming business, production of tobacco products, alcohol, precious metals, etc.); choice of taxation system (general or simplified system); simplified forms of accounting are provided; the use of accountants on the terms of outsourcing (without employment in the company's staff); the use of modern software-based cash registers (PPO) as a replacement for traditional cash registers (RRO); simplified form of financial reporting; accounting calendar for reporting; the ability to quickly close a business through the Diya platform.

The level of organization of accounting affects the effectiveness of ensuring the entire system of interests of users of financial reporting and the functioning of accounting at the enterprise, as well as its reliability, timeliness and effectiveness in general. The authors of the article indicate the importance of using modern PPO or "cash registers in smartphones", which is one of the important components of conducting business without fines for most SPs. An analysis of the dynamics of the use of modern PPO and RRO programs was carried out, in particular, the number of payments that were recorded under both systems during 2023 and the beginning of 2024. A comparative characteristic of the features of the use of PPO and RRO was given. The advantages and disadvantages of each type of cash register are determined. The tax regulation regarding fines, which are most often applied to business, is covered. The prospects for the activity of SPs in Ukraine in the near future were studied. It was found out, according to the draft Law of Ukraine No. 11416(d), that it is planned to make amendments and additions to the Tax Code of Ukraine in terms of increasing taxes for private enterprises, unification of some groups of the simplified taxation system, etc.

The business prospects of SPs are indicated, taking into account the National Revenue Strategy until 2030.

Internal control of labour remuneration as a component of cost management in a construction company

Liubov ZGALAT-LОZYNSKA — 2025-01-05

The article is devoted to the issue of formation of effective internal control of labour remuneration at construction enterprises as an important component of cost management. The article proposes a methodical approach to organisation of internal control of labour remuneration, identifies its main stages: regulatory and legal support, planning and labour rationing, accounting of working hours and documentation, control over compliance with labour legislation, control of payroll and deductions from the payroll fund, analysis of the structure of the payroll fund and assessment of efficiency of its use, feedback and adjustment of control methods.

It is determined that the role of internal economic control is to ensure the correctness of cost accounting, compliance with labour legislation, minimise the risks of cost overruns and develop ways to optimise labour costs. Control contributes to the formation of a transparent system of interaction between the company's departments, efficient use of labour resources, prevention of financial abuse and achievement of strategic goals.

The authors emphasise the importance of accounting and analytical support, regulatory frameworks and the use of modern control methods that improve the quality of management decisions. Particular attention is paid to the analysis of the structure of the labour remuneration fund and the efficiency of its use. It has been found that systematic audits, regular monitoring and data analysis help to identify reserves, optimise costs and ensure the competitiveness of the enterprise. It is recommended to introduce a unified information system to integrate accounting and control processes between the enterprise's departments.

The study has identified a number of problems in the system of internal control of labour remuneration at construction enterprises, in particular, errors in documentation, difficulties with accounting for liabilities and classification of payments. These processes need to be improved to improve the efficiency of managing personnel costs.