This article systematizes reinforcement methods based on their operating principle and the materials used, identifying key trends: the dominance of technologies based on composite external reinforcement materials and the active development of hybrid systems. A classification scheme has been developed that allows for the informed selection of reinforcement methods based on the technical condition of the structure and the desired result.
The article demonstrates the high effectiveness of composite materials in increasing strength and seismic resistance with a minimal increase in cross-sectional weight. It is determined that traditional methods (reinforced concrete casings, shotcrete) remain relevant when a significant increase in rigidity is required. Promising areas for implementation are identified: the adaptation of international standards, the development of domestic equivalents of high-performance composites, and the creation of digital reinforcement models.of investments in interests of the organization and development of new production on available floor spaces. The most important organizational economic targets of a diversification of management are presented by innovative activity of the industrial enterprise.

Keywords: structural reinforcement, operational load, columns, composite materials, carbon fiber, seismic resistance, shotcrete, steel casings, fiber-reinforced concrete, hybrid reinforcement

The article discusses the current threats posed by unmanned aerial vehicles and their impact on the development of the legal and regulatory framework for construction safety in Russia. Based on an analysis of regulatory documents, the article explores the phenomenon of law substitution and the obsolescence of the legal and regulatory framework for construction safety. The author proposes an initial approach to addressing these issues by modernizing the legal framework for building and structure safety. To achieve this, the author has formulated new concepts that are recommended for inclusion in the key law and that lay the foundation for a new institution of unmanned (anti-drone) security in the construction industry.

Keywords: regulatory legal act, regulatory technical act, law replacement, unmanned aerial vehicle, threat of an unmanned aerial vehicle, unmanned anti-drone security, unmanned danger

The article presents the results of a comprehensive analysis of existing methods and approaches to prevent progressive collapse of reinforced concrete structures.  As part of the work, a systematic study was conducted of both the theoretical foundations of the phenomenon of progressive collapse and practical methods for ensuring structural stability. The theoretical basis of the work was made up of domestic regulatory and technical documents, as well as scientific publications and specialized research in the field of survivability of building structures. The practical significance of the research lies in the systematization of knowledge about methods of countering progressive collapse, which is valuable for design engineers working to create safe and reliable structures. The results of the study can be used to further improve approaches to the design of structures, taking into account the requirements of resistance to progressive collapse.

Keywords: progressive collapse, structural survivability, construction, reinforced concrete, large-panel building, monolithic reinforced concrete building, loss of stability, primary structural system, secondary structural system, volumetric and planning solution

The article presents a review of contemporary Russian and international studies devoted to the barriers hindering the implementation of circular economy principles in the construction industry. It examines economic, regulatory, technological, and socio-cultural constraints that impede the transition from a linear to a circular production model. The analysis of recent publications identifies key challenges, highlights the interrelation of barriers, and emphasizes the importance of an integrated approach to overcoming them. Based on the synthesis of the reviewed sources, it is concluded that a successful transition to a circular model requires systemic changes in legislation, financing, technology, and public awareness.

Keywords: circular construction, circular economy, barriers, economic constraints, regulatory framework, secondary raw materials, technological innovation, institutional barriers, environmental education, sustainable development, recycling

This article examines the potential of modern lighting technologies to address the need to select energy-efficient lighting equipment for outdoor urban portable pavilions. The article analyzes the technical characteristics of the main types of modern lighting systems based on LED and OLED technologies.

Keywords: artificial lighting, energy saving, LED systems, OLED systems, hybrid systems, energy efficiency, autonomous structures, lighting technologies

The article discusses the problems and solutions of 3D printing and additive manufacturing in the context of the integration of artificial intelligence. With increasing demands for quality and efficiency, artificial intelligence is becoming a key element of process optimization. The factors influencing the suitability of models for 3D printing, including time, cost and materials, are analyzed. Optimization methods such as genetic algorithms and machine learning can simplify testing and evaluation tasks. Genetic algorithms provide flexibility in solving complex problems, improve quality, and reduce the likelihood of errors. In conclusion, the importance of further research on artificial intelligence for improving the productivity and quality of additive manufacturing is emphasized.

Keywords: artificial intelligence, 3D printing, additive manufacturing, machine learning, process optimization, genetic algorithms, product quality, automation, productivity, geometric complexity

Polyurethane foams (PUFs) constitute a major class of polymeric materials, widely appreciated for their excellent mechanical strength, chemical resistance, and physical versatility. They are used in a wide variety of applications, such as insulation, cushioning, coatings, and structural parts. Traditionally, PUFs are prepared through polyaddition reactions involving polyols, diisocyanates, and water, where the in-situ generated CO₂ in the reaction mixture serves as the blowing agent. However, there are significant concerns with the use of isocyanates as they are toxic, classified respiratory sensitizers, and contribute to environmental pollution. These issues have directed both researchers and industry experts to search for safer and more sustainable alternative feedstocks.
The polyaddition reaction between cyclic carbonates (CCs) and polyfunctional amines has been one promising alternative. The reaction leads to the formation of non-isocyanate polyurethanes (NIPUs), specifically polyhydroxyurethane foams (PHUFs). Foaming is achieved by using external chemical blowing agents or through self-blowing reactions, where gases are generated directly in the system. The generated   foam cells – the structures that give foams their unique properties – depends largely on the gas-forming reactions.
This review focuses on the different blowing agents used in NIPUF synthesis, such as poly(methylhydrogensiloxane) (PHMS) and liquid fluorohydrocarbons. It also looks at recent advances in self-blowing techniques, which eliminate the need for external agents and make the process more sustainable. Special emphasis is placed on NIPUFs derived from renewable feedstocks, as these align with global trend towards green chemistry and circular materials. The review provides an overview of both externally blown and self-blown biobased NIPUFs, detailing their synthesis, performance, and potential industrial applications.

Keywords: biobased polyurethane, blowing agent, non-isocyanate polyurethane, polymeric foams, polyurethane foams, self-blowing

 The article examines the influence of various industrial waste on the strength characteristics of concrete using the method of multifactorial experimental design. Three types of additives are considered: waste from sand-and-resin casting molds, aluminum powders from gas-dynamic spraying, and rubber crumb from used tires. The use of waste allows for increased environmental friendliness and cost-effectiveness of concrete mixtures, as well as improved performance of materials. Experimental analysis revealed changes in the strength of concrete depending on the type of cement, type of waste, and percentage of natural sand substitution. The results obtained open up new opportunities for the development of sustainable construction.The article provides statistical data on the industry's contribution to global CO₂ emissions and justifies the need for the use of environmentally friendly materials. The "Materials and Methods" section outlines the methodology for conducting a multi-factorial experiment using the Latin square method to study the effects of three factors: the type of cement (M300, M400, and M500), the type of additive (casting molds, aluminum powders, and rubber chips), and the percentage of natural sand substitution (10%, 20%, and 30%). The article also describes the testing conditions and justifies the reduction in the number of experiments.The "Results" section presents data on the strength of concrete samples, explaining the greatest influence of the cement brand, the average influence of the substitution percentage, and the least influence of the type of waste. Empirical formulas derived from the results allow for the prediction of concrete strength under various combinations of factors. The "Conclusions" section highlights the practical significance of the work. It discusses the potential for cost reduction and environmental benefits from the use of industrial waste, as well as providing recommendations for the optimal composition of concrete mixtures for different applications.

Keywords: multifactorial experiment, research planning methodology, strength, concrete, industrial waste

In modern construction, special attention is paid to improving the energy efficiency of buildings. One of the key elements affecting energy consumption is the design of the exterior walls, which directly determines the heat loss of the building. The purpose of this work is to analyze and optimize the design of exterior walls of civil buildings, taking into account modern energy efficiency requirements, as well as to study the effect of various thermal insulation materials on reducing energy consumption. The study examines various types of exterior walls, including single-layer and multi-layer structures, as well as the possibilities of improving their thermal performance using modern thermal insulation materials.

Keywords: energy efficiency of buildings, thermal protection, multilayer structures, heterogeneous fences, heat loss, thermal resistance, insulation, cold bridges, mineral wool, aerated concrete, thermal modernization

Long-term operation of a building and untimely repairs lead to damage in load-bearing structures, such as destruction of anti-corrosion protection, surface corrosion, layered and deep corrosion of metal. In reinforced concrete columns, frequent damage includes cracks along the working reinforcement, concrete chips at the corners with exposure of reinforcement rods, separation of the concrete cover, corrosion of the working reinforcement. In this case, the question arises about the impact of the identified damage on the technical condition of the structure. The survey of production buildings and structures is carried out in order to determine the technical condition of building structures and obtain quantitative indicators of the quality and load-bearing capacity of building elements and the entire building. The article presents the results of calculating the loss of potential load-bearing capacity of a metal column and beam, and also discusses the process of degradation of a reinforced concrete cross-section and the loss of load-bearing capacity of a column due to the development of corrosion of reinforcement rods. The article will be relevant for specialists and experts in the field of industrial safety expertise and building and structure inspection.

Keywords: metal columns, metal roof beams, loss of load-bearing capacity, surface corrosion of the column metal, deep corrosion of the column metal, technical condition of the roof beams, corrosion of the roof beams

The problem of the ultimate external pressure on a thick-walled concrete pipe internally reinforced with a metal pipe is considered. The pipe material is assumed to be ductile, not hardening under small deformations. The problem is solved under the assumption of plane strain. The stress state in the concrete mass and along the contact surface between the metal pipe and the concrete is investigated, assuming the concrete is in the ultimate limit state. A law for the change in the stress state in the concrete mass and a transcendental equation for determining the ultimate pressure on the outer surface of the concrete shell are derived. The ultimate uniformly distributed load acting on the outer surface of the concrete shell, within which the metal pipe is placed, is determined.

Keywords: concrete deformability, strength criterion, ultimate limit state, stress state in the concrete mass, ultimate pressure

The development of remote and hard-to-reach territories of Russia requires effective construction solutions that combine high performance, environmental friendliness, and full factory readiness. This article presents the results of a study on modified arbolite designed for use in the production of volumetric spatial modules. To improve the physico-mechanical properties of the conventional composition, a comprehensive chemical modification of the wood aggregate was applied, including preliminary treatment with aluminum silicate (Al₂SiO₅) followed by the introduction of ethanedioic acid into the mixture. It has been experimentally established that the proposed modification leads to a statistically significant reduction in the average density of the material by 11%, while simultaneously increasing the compressive strength by 47% compared to control samples. The physico-chemical strengthening mechanism, consisting in the formation of an organo-mineral framework within the wood structure, is substantiated. The results demonstrate the high potential of the developed material for use as a structural and insulating component in modular construction for regions with extreme climatic conditions.

Keywords: modified arbolite, modular construction, aluminosilicate, ethanedioic acid, compressive strength, and density

One of the ways to reduce the construction time of nuclear power plants is to use prefabricated monolithic construction technology with the use of prefabricated formwork blocks consisting of a reinforcement frame and sheets of non-removable formwork made of high-strength steel fiber concrete. After installation in the design position, the prefabricated elements are filled with self-compacting concrete mixture, significantly reducing labor costs on the construction site. Self-compacting concrete mixtures are characterized by high mobility and a significant content of cement paste, which increases the requirements for ensuring the tightness of the formwork system. The article describes the results of experimental studies on the parameters of filling the technological gaps between the sheets of non-removable formwork with self-compacting concrete mixture at different heights of its placement. The article also provides a description of a laboratory setup that allows for the simulation of the pressure of freshly placed concrete.

Keywords: nuclear power plant, permanent formwork, structural testing, steel fiber reinforced concrete, self-compacting concrete mix, formwork pressure

In the practice of constructing underground hydraulic structures, conditions often arise that require careful attention to gas forecasting. Such forecasting can be based on an analysis of the geological and tectonic structure of the area, a study of the mineral composition, degree of lithogenesis, rock chemistry, temperature and gas composition, groundwater sources, etc. The problem of ensuring the reliability of underground structures is complicated by the high seismicity of the areas in question, significant natural stresses, often comparable to the strength of the rock, and the presence of faults along tunnel routes.

Keywords: water inflow, geology, landslides, tunnels, orogenic regions, tectonic processes, relief, exogenous processes, clay, loam, limestone

The relevance of the study is due to the fact that: firstly, the proposed topic is in line with the Government-approved "Strategy for the development of the construction industry and Housing and Communal Services of the Russian Federation for the period up to 2030 with a forecast up to 2035" dated October 31, 2022, which assumes an increase in the share of industrial housing construction, including panel construction; secondlySecondly, the existing methods for calculating the joints of panel buildings have come down to us almost unchanged from the level of development of construction science and engineering in the 1980s. of the last century, which leads to increased material costs and rising real estate prices, therefore, the current trend in the development of the construction industry requires the improvement of these techniques. Modern approaches to nonlinear modeling and calculation of reinforced concrete will allow, in relation to panel joints, to reveal the reserves of their bearing capacity and obtain a more rational design, which will reduce the cost of constructing the buildings in question as a whole. PURPOSE. To carry out a comparative analysis of existing methods for calculating panel joints in two groups of limit states, to identify their advantages and disadvantages. Identify ways to improve them. METHODS used in the course of the research: theoretical methods – chronological, formalization, classification, analysis, synthesis, generalization, comparison. RESULTS. The analysis of existing methods of foreign and domestic design standards, as well as various author's methods, showed that: 1) foreign and domestic standards are based on the limit state method; 2) the nonlinear deformation model is not used in the calculation of joints of reinforced concrete panels; 3) to obtain a more accurate VAT of reinforced concrete panel joints, it is necessary to process a large amount of data using computer technology. CONCLUSION. The analysis shows that the use of computer software systems is the most promising method for calculating building structures, allowing fast and accurate calculations, reducing the cost of construction.

Keywords: large-panel construction, reinforced concrete, panel joint, joint calculation, joint classification, platform joint, deformation model, limiting forces, computer modeling, finite element

This study's objective is to assess the extent to which Western architecture influences the design of hotel structures in post-colonial cities using Freetown as a case study. Using a qualitative approach, this study draws on historical records of post-colonial hotel buildings, interviews with architects, and employs a comparative case study to compare colonial hotel projects in Freetown. Most hotels built after colonization still maintained properties of Western influence. Some designs were transcended by architects, others by the owners of the projects themselves, asking architects to replicate the same designs they saw abroad.   Theoretically this study suggests and provides evidence of a borrowed model of architecture of hotels largely influenced by western architectural design styles for which this is not sustainable and Sierra Leone needs to find its own architectural language. This research adds to the cultural theory of transcending architecture, where hotels built in a post-colonial era still retain designs passed on from colonial masters. Not enough research has examined the postcolonial effects on the architecture of hotels in past colonized cities. 

Keywords: post-colonial, hotel design, Western influence, architecture

This article examines the influence of used saw blade surface roughness parameters on the load-bearing capacity of adhesive joints in wood-metal composites. Various methods of steel surface preparation, including mechanical and abrasive treatment, are considered. The focus is on establishing a quantitative relationship between metal surface roughness and adhesive joint strength with varying reinforcement depth and adhesive layer composition. Experimental studies were conducted using the Protodyakonov-Teder multifactorial design method. It was found that surface treatment method has a decisive influence on the load-bearing capacity of the joint, and optimal roughness ensures maximum mechanical adhesion between the adhesive and the metal.

Keywords: multifactorial experiment, roughness, load-bearing capacity, wood-metal composite, adhesive joint, used saw blade

The article examines the features of adaptive design in construction as a fundamental component for ensuring life safety in the zone of a special military operation. The modern world is changing at an incredible pace: climate anomalies are becoming more frequent, technological paradigms are being replaced within years, and social and economic conditions are undergoing constant transformations. Nowhere are these challenges manifested as acutely and concentratedly as in the zone of a special military operation (SMO). It is precisely here that the traditional approach to construction, focused on creating static, "frozen" objects, proves not only ineffective but also dangerous. It is being replaced by adaptive design – a philosophy and methodology that views a building or infrastructure object not as a final product, but as a living, evolving organism capable of evolving in response to direct threats and changing operational conditions. Adaptive design is a strategy for creating architectural objects and urban planning systems that can be easily modified, transformed, or repurposed in response to changes in external or internal conditions. In peacetime, this is a response to changing markets and technologies. In the zone of a special military operation, it is a matter of ensuring life safety. This is not simply post-factum repair or reconstruction, but the inherent ability of an object to instantly change its function and protective properties without radical rebuilding. The experience of the special military operation zone has openly proven that adaptive design is not an abstract idea from construction textbooks, but a critically important discipline upon which people's lives and the success of the assigned task depend. The principles of flexibility, modularity, and multifunctionality that are being tested today in extreme conditions will tomorrow become the new standard for the entire construction complex of the Russian Federation. They will form the basis for the restoration of cities, the creation of sustainable civil infrastructure, and the formation of new, anti-crisis architecture capable of withstanding the challenges of both wartime and peacetime. In the zone of a special military operation, architectural heritage is being tested and created, which will remain functional, in demand, and sustainable tomorrow. The future of construction belongs to those who design not for years, but for possibilities.

Keywords: adaptive construction, modern trends, modern design technologies, construction industry, construction processes, special military operation

The results of a study of the shrinkage, mechanical properties, and durability of slag-lime concrete modified with machine and vegetable oils are presented. To determine the effect of the oils, the physical and mechanical properties (setting time, compressive strength, and autogenous shrinkage) were tested. The experimental results show that using oil as a structure modifier for slag-lime concrete can significantly reduce its autogenous shrinkage by reducing surface tension and creating a denser internal structure. It was found that emulsified oils provide superior physical and mechanical properties to concrete compared to non-emulsified oils. The setting time is also longer than in compositions without an organic modifier. The use of emulsified oils reduces the negative properties of slag-lime concrete, such as shrinkage, cracking, and reduced setting time.

Keywords: metallurgical waste, granulated slag, hardening activator, binder, superplasticizer, setting time, spray, strength

In reinforced concrete design standards, the values of concrete strain are taken as average values, whereas the strength characteristics are adopted with a high level of reliability. In the ultimate force method for calculating reinforced concrete structures, the strains of concrete and reinforcement are not directly used in the governing equations. In calculations based on the nonlinear deformation model, the strain values are directly used in the analysis. Using average values of the ultimate strains of concrete reduces the reliability of the obtained results. This study examines the influence of the variability of deformation characteristics of concrete and reinforcement on the load-bearing capacity of eccentrically compressed reinforced concrete elements. It was found that the variability of the deformation characteristics of concrete and reinforcement significantly affects the load-bearing capacity of eccentrically compressed reinforced concrete elements. This influence increases with the reinforcement ratio and depends on the eccentricity of the applied axial force. The reliability and safety of eccentrically compressed reinforced concrete elements decrease significantly when average values of the deformation characteristics of concrete and reinforcement are used in calculations.

Keywords: eccentric compression, reinforced concrete, variability of deformation characteristics, concrete, load-bearing capacity, reinforcement, nonlinear deformation model

The article discusses the issues of stability of single-layer cylindrical rod roofs and establishes the suitability of the theory of thin solid shells for similar-shaped core structures. An analysis of the factors was carried out to determine the magnitude of the critical load and the need to take into account the parameter characterizing the change in the geometry of the structure along the arc of the circle was proved. The values and ratio of flexural and membrane stiffness are obtained depending on the possible number of half-waves of the shape of the loss of stability, and a pattern for determining the critical load is established.

Keywords: cylindrical rod roofs, stability, critical load, stiffness, number of half-waves

The article examines the aspects of using bionics as a basis for adaptive architecture and construction in the conditions of the North Caucasus. Modern architecture is undergoing a shift from static and resource-intensive models to dynamic, intelligent and environmentally oriented systems. This approach is particularly relevant for regions with difficult climatic and landscape conditions, such as the North Caucasus, where traditional construction is often unable to effectively withstand the challenges of sudden temperature fluctuations, seismic activity, strong winds and high insolation. This article substantiates the thesis that the integration of bionics principles into adaptive construction offers not just innovative solutions, but a holistic design philosophy based on centuries of experience in the evolution of natural systems. It is proved that bionics is not an alien concept for the region, but, on the contrary, finds deep parallels in traditional mountain architecture, such as in tower complexes demonstrating organic integration into the landscape and effective thermoregulation, similar to natural prototypes. The paper discusses specific areas of application of bionic principles, including the development of adaptive facades inspired by plant and animal thermoregulation systems, as well as the creation of earthquake-resistant structures similar to the flexible structures of bamboo stems or trees. Special attention is paid to the design methodology that combines the analysis of local conditions, biomimicry methods and the integration of modern digital technologies such as computer modeling and 3D printing to create unique, energy-efficient facilities. The need for synergy between traditional architectural knowledge and innovative technologies is emphasized, which makes it possible to create buildings that not only adapt to the environment, but also reflect the unique cultural identity of the North Caucasus. In conclusion, it is argued that bionics is a logical and promising direction for the architectural development of the region, ensuring the creation of a sustainable, safe and comfortable living environment through harmonization with the natural context.

Keywords: construction, bionics, modern trends, modern design technologies, construction industry, biomimicry, adaptive architecture, North Caucasus

The paper analyzes the influence of damage to the protective layer of concrete of the zone of maximum bending moments of single-span beams on the load-bearing capacity of the structure and the possibility of restoring the initial load-bearing capacity. The study is based on laboratory research and numerical experiment, as well as on the analysis of earlier tests and accumulated experience in the restoration of structures. As a result, conclusions are drawn about the effect of concrete protective layer failure on the load-bearing capacity of bending structures, and recommendations are given for further research into the calculation and design of these systems.

Keywords: damage of concrete protective layer, corrosion of reinforcement, restoration, reinforcement

Axial tests demonstrate that strengthening reinforced concrete columns with carbon fiber reinforced plastic (CFRP) significantly improves their performance through lateral restraint. The circular winding creates a triaxial compression effect, increasing concrete strength and load-bearing capacity. The slows of carbon fiber brittle fracture, increases ductility, suppresses microcracks, and improves seismic resistance. This technology is lightweight, corrosion-resistant, and has low operating costs.
The effectiveness of the reinforcement depends on the number of layers and the winding pitch. Cylindrical columns respond better to reinforcement; square columns require rounded corners (radius ≥20 mm) to prevent stress concentration. Two to three layers of CFRP are recommended. This method is particularly effective for columns with insufficient load-bearing capacity, low ductility, or in seismic conditions.

Keywords: carbon fiber, reinforcement for reinforced concrete columns, compressive load bearing capacity

This paper provides an overview of modern stochastic and analytical models describing the effect of reinforcement corrosion on the system reliability and residual load-bearing capacity of reinforced concrete beams. Special attention is given to pitting corrosion as the dominant mechanism of strength degradation. Methods for estimating initiation time and progression of corrosion are summarized; criteria for the transition from ductile to brittle failure mechanisms and the assessment of moment redistribution losses are analyzed. Practical recommendations are provided for adjusting safety factors during the design and operation of such structures under high variability conditions.

Keywords: reinforced concrete, rebar, corrosion, pitting, system reliability, degradation, Gumbel distribution, reliability index, moment redistribution