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The effect of the temperature difference in the thickness of three-layer reinforced concrete enclosing structures in the operational stage on their stress-strain state

https://doi.org/10.58224/2618-7183-2025-8-1-5
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Аннотация
In three-layer reinforced concrete structures, the inner and outer layers of concrete of different physical and mechanical characteristics have different coefficients of thermal conductivity and linear temperature deformation. During the operation of buildings and structures, due to the temperature difference in the thickness of the structure along the contact planes of the layers, shear stresses may occur, which leads to bending of the structure, an increase in its deflections and a decrease in crack resistance. In this regard, when designing and calculating such structures, it is necessary to take into account the operational stresses and deflections caused by the temperature difference in the thickness of the enclosing structure.
Taking into account the fact that the cross-section of three-layer enclosing structures with a monolithic connection of layers includes various types of concrete and reinforcement, differing in the values of the initial modulus of elasticity, to solve the problem, the cross-section of the enclosing structure is reduced to a homogeneous one corresponding to the largest initial modulus of elasticity of the concrete of the outer layers.
Studies have been carried out to identify the effect of the thickness of the enclosing structure on the change in deflection, depending on the temperature difference, and its share in the total deflection of the structure. Despite the fact that the calculation results revealed a slight increase in the total deflection, taking into account the proportion of deflection that depends on the temperature difference, the study allows us to increase the accuracy of the calculation. The tendency to reduce the material consumption of structures and, consequently, a decrease in the thickness of the structure can lead to an increase in the proportion of deflection, depending on the temperature difference, which must be taken into account when choosing design solutions.
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Predicting the risk of early cracking in massive monolithic foundation slabs using artificial intelligence algorithms

https://doi.org/10.58224/2618-7183-2025-8-1-6
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Аннотация
The article presents a study of the application of artificial intelligence algorithms in predicting the risk of early cracking in massive reinforced concrete structures using monolithic foundation slabs as an example. The current experience of using algorithms such as convolutional neural networks, deep learning tools (YOLOv5 model) for crack detection at various stages of the life cycle of massive reinforced concrete structures is analyzed. The causes of crack formation, physical and mechanical processes, including cement hydration are considered.
A model has been developed that predicts the magnitude of the tensile stress level in monolithic foundation slabs during construction, based on CatBoost using Python, allowing to predict the risks of early cracking with an accuracy of up to 98%.
The model was trained on synthetic data containing various design parameters and material properties, including the geometric dimensions of the slabs, the temperature on the upper surface, the heat transfer coefficient on the upper surface, the curing rate, the class of concrete and the characteristics of the soil base. Statistical analysis of the data was performed, a correlation matrix was constructed. Practical and predicted values of the model were visualized in the form of a scatter plot. The most significant parameters influencing the risk of early cracking in massive monolithic foundation slabs were obtained. The constructed model passed quality assessment according to three metrics: MAE=0.0011; MSE=4.038; MAPE=0.0014.
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The effect of the aerodynamics of indoor air flows on the power of the heating system

https://doi.org/10.58224/2618-7183-2025-8-1-7
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Аннотация
An analytical dependence is presented for calculating the power of a heating system, taking into account the aerodynamics of the movement of air flows inside a heated room. The analytical dependence is derived on the basis of the theory of a two-zone mathematical model of a heated room. The method allows us to determine a rational way of organizing heating to ensure minimal transmission heat loss through enclosing structures, taking into account factors affecting thermal and air processes in a heated room and contributing to a decrease in the power of the heating system as a whole. The results of the analysis carried out on the regularity of the movement of air flows in a room divided into two control volumes (CV): upper and lower CV. A mathematical model of the processes of heat and mass transfer of a heated room in an administrative or residential building has been developed, which takes into account the heat exchange between the upper and lower CV. The physical picture of the distribution of air and heat flows in a heated room with a local heat source located in the window sill space of the heated room is analyzed. A method for calculating the power of the heating system is proposed, taking into account the nature of the aerodynamics of the distribution of air flows in a heated room. An analytical dependence for calculating the thermal power of a heating system is presented, taking into account the characteristics of the distribution of heat and air flows across two control volumes of the heated room.
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Factors of territorial resource use in the reconstruction of multi-purpose healthcare facilities

https://doi.org/10.58224/2618-7183-2025-8-1-8
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Аннотация
Medicine is one of the most important directions for the country development and has a fundamental position in the socio-economic policy of the state, ensuring the human health and well-being. With the development of medical technologies, the standards of medical care are also growing, and the requirements to healthcare facilities are becoming more stringent. In the conditions of dense urban development, the construction of a multi-purpose medical center that fully meets the standards may be problematic, and therefore the possibility of reconstruction of existing healthcare facilities to meet up-to-date requirements is being considered. The purpose of this article is to determine the possibility of reconstruction of multi-purpose healthcare facilities through densification of development; to analyze the methods of densification in relation to the territories of multi-purpose healthcare facilities; and to detect the architectural principles in the densification of development of multi-purpose healthcare facilities. The article authors also show the architectural techniques used in reconstruction with an increase in the technical and economic indices of the facility. The methodology of this research represents the analysis of academic papers, as well as the analysis and generalization of practical experience in the architectural design and reconstruction of multi-purpose healthcare facilities, including the personal experience of the article authors. The result of the research is the determination of the basic principles of the reconstruction of multi-purpose healthcare facilities, which make it possible to create the up-to-date typology of a healthcare facility, and have an impact on the formation of the architecture of multi-purpose healthcare facilities. The research is aimed at forming the up-to-date typology and architecture of multi-purpose healthcare facilities during reconstruction.
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Methods for assessing the quality of architectural spaces of educational institutions

https://doi.org/10.58224/2618-7183-2025-8-1-9
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Аннотация
School plays a key role in the development of a person's personality throughout their life. The educational atmosphere largely shapes behavior patterns, especially for children and adolescents. The foundations laid at an early age often become decisive for the further development of the personality. Today, approaches to the educational process have undergone significant changes. The article presents a methodology developed by the authors that allows assessing the quality of architectural spaces of educational institutions by four main parameters. This will allow obtaining an objective picture of the state of educational spaces and making adequate architectural and design decisions at the administrative level. This work is based on an integrated approach to assessing architectural space, developing universal assessment models that allow correlating different-quality characteristics of school subsystems into a single assessment system, which will allow obtaining a quantitative assessment of the state of spatial indicators of educational institutions. Methods for assessing architectural spaces of educational institutions suggest entering a new stage of designing specific schools, eliminating serious consequences of architectural and design errors with large budget losses when implementing poor-quality development scenarios. The priority task of reforming the system of public authority is to create a qualitatively new level of public administration efficiency, including in matters of spatial development of educational institutions and renovation of existing schools. Because of the study, the main criteria and indicators of the quality of the architectural educational space were developed. The matrix of criteria includes such evaluation blocks as safe environmental design; formation of space; inclusiveness; stages of the physical condition of the building. The evaluation criteria were tested and refined in schools of the Republic of Bashkortostan. The results of the project implementation are methodological tools for assessing the quality of architectural spaces of educational institutions, an application for assessing the initial level of quality of architectural space, modeling the architectural planning solution of an educational institution and estimate documentation at the stage of an application for major repairs.
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Principles of the organization of space-planning solutions for nuclear medicine facilities

https://doi.org/10.58224/2618-7183-2025-8-1-10
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Аннотация
It is nearly impossible to imagine modern medicine without the use of nuclear technologies, the introduction of which has led to the emergence of new methods of prevention, diagnosis and treatment of various diseases, as well as reduced mortality rates among patients and improved the quality of life of patients with diseases in the field of oncology, cardiology, neurology and others. The purpose of this article is to systematize the principles of the organization of architectural space-planning solutions based on the studied experience of the constructed nuclear medicine facilities. The methodology of this research constitutes an analysis of statistical data and academic papers, in which the authors examine the core process equipment used at nuclear medicine facilities, the main architectural typological zones of nuclear medicine facilities, and highlight the requirements to the premises in which the source of ionizing radiation is located. In addition to the analysis of academic papers, the methodology of this research includes the analysis of practical experience in the architectural design and construction of nuclear medicine facilities, as a result of which the authors analyzed space-planning and architectural solutions used in the design and construction of nuclear medicine facilities. As part of this article, the authors present, in particular, an analysis of the experience of personal design of a number of Russian nuclear medicine facilities. Furthermore, special attention in the article is paid to the principles of architectural and planning solutions for children’s medical institutions (in particular, with oncological specialization). The result of the research is to build up a sketch model of the space-planning solution of the nuclear medicine facility as a multi-purpose facility, to determine the principles that affect the formation of space-planning solutions. The research is aimed at forming a space-planning solution for a multi-purpose nuclear medicine facility, taking into account the possibility of increasing its capacity during operation.
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Field thermal imaging surveys of residential buildings – a prerequisite for the development of energy-efficient external enclosures

https://doi.org/10.58224/2618-7183-2024-7-6-1
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Аннотация
The work involved a full-scale thermal imaging survey of a residential building during a hot period of time, where the effect of solar heating of the building's façade and the inner surface of the outer enclosure was studied, taking into account the orientation of the building and the time of the survey. As a result, it was found that the effect of solar heating on the building’s façade significantly increases the temperature on the façade surface, where, depending on the façade orientation and time, the building’s façade surface is exposed to heating from the east, west and south sides. Thus, the maximum values of the façade surface temperature reach 63.1°C, 57.0°C and 53.4°C, respectively, which is almost twice as high as the initial temperature values. Solar heating also has a significant effect on the temperature of the inner surface of the external enclosure, also depending on the façade orientation. Thus, on the east side in the morning, the surface temperature of the external enclosure increases by 3.8°C, which continues until 16:00. The influence of the sun provokes heating of the inner surface of the external enclosure of the living room on the western side by 4.2°C, and on the southern side the maximum temperature on the surface of the inner enclosure was observed in the period from 12:00 to 16:00, which exceeded the initial one by up to 3.8°C. At that, the influence of heating from the sun on the northern side was not observed. With that, it was found that the influence of solar heating of the building façade provokes deviations in the microclimate of the room, where the deviation in the permissible internal air temperature of the living room is 14.1% during the day, and in the optimal humidity by 13.3% in the afternoon. The findings of this study can be taken into account when designing or developing new energy-efficient external enclosing wall structures, where the criterion of heat resistance must also be taken into account in parallel with the criterion of heat protection in the climatic features of the Republic of Kazakhstan.
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Developing administrative and process-related solutions for the benefit of residential construction projects

https://doi.org/10.58224/2618-7183-2024-7-6-2
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Аннотация
Housing construction is a key segment of economy in any country, as it satisfies the needs of population and ensures safe living conditions.
This segment must take into account the requirements of safety, environmental friendliness, energy efficiency and limited mobility, resulting in high-quality construction products within pre-set deadlines. Due to the fact that many parties are involved in the construction of buildings, numerous processes are underway. As a result, various risk factors may arise. They may cause a failure to meet deadlines and lower quality of work.
The authors propose administrative and process-related solutions aimed at eliminating the most substantial risk factors.
The study solves the following tasks: analyzing the general contractor's activity in residential construction; studying risk factors that affect the building construction period; identifying actions aimed at mitigating risk factors by applying administrative and process-related solutions; developing and implementing a novel method developed on the basis of the research projects.
An expert survey was conducted among the top specialists from the construction industry, and a list of risk factors arising during the construction of residential buildings was made.
As a result, a method is developed that enables the pre-assessment of potential construction risk factors and elimination or minimization of their effect. This method reduces the period of construction, improves the quality of construction facilities and, on the whole, increases labor productivity.
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Application of ash and slag waste from coal combustion in the construction of the earth bed of roads

https://doi.org/10.58224/2618-7183-2024-7-6-3
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Аннотация
More than 1.5 billion tonnes of ash and slag waste from thermal power plants have been accumulated in the RF. The most promising direction of reuse is construction and repair of roads. The most material-intensive direction is the construction of earth bed. The aim of the study is to expand the practice of using ash and slag mixtures from thermal power plants for the construction of roadbeds in continental and polar climate. In order to achieve the goal set in the work the ash and slag mixture from different ash dumps of Irkutsk region was sampled. Ash and slag wastes can be considered as technogenic soils and classified according to GOST 25100 as gravelly sands and dusty sands. Ash and slag mixtures do not possess cohesion, have low values of internal friction angle, high porosity of particles and low specific weight, and small frost heave deformation. To evaluate the efficiency of ash and slag mixtures application in the structures of the roadbed of roads the design and construction of the roadway and the roadbed on the section of the road in the Irkutsk region was carried out. The technology of works on construction of earth bed layers from ash and slag mixtures is similar to the technology of erection of layers from soils. The constructed construction of road with earth bed from ash and slag mixtures has operational characteristics not lower than the construction of the adjacent road section with earth bed from local soils. Ash and slag mixtures can be used for construction of earth bed layers practically without restrictions.
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Development of geopolymer binders

https://doi.org/10.58224/2618-7183-2024-7-6-4
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Аннотация
The scale of consumption of raw materials is large, and to a greater extent, it is the building materials industry that has a detrimental effect on the environment, thereby disturbing the pristine appearance and landscape of nature. Production volumes of Portland cement clinker have exceeded the mark of 5 billion tons per year. But the key dilemma lies in the emission of greenhouse gases, because during the high-temperature processing of raw materials to produce clinker, carbon dioxide, methane and nitrous oxide are released into the atmosphere.
At the same time, slag-alkali and geopolymer binders can be considered as an alternative to resource-intensive Portland cement; they have found practical application in many developed countries of the world. A large backlog of research has allowed the authors of the work to model materials of both technogenic and natural origin “technogenic reaction powder – natural component – alkaline activator” in one binder system. Microanalysis confirmed the effectiveness of the integrated use of sodium silicofluoride and finely dispersed bentonite additives in the binder system, which had a beneficial effect on the pore structure of the stone and the properties of the cement stone.
Using a properly designed binder composition “aspiration dust – finely dispersed bentonite – sodium silicofluoride – alkaline binder”, it is possible to obtain high-quality and durable composites with a low carbon footprint, thereby solving many environmental problems.
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