Against the backdrop of tightening requirements to reduce production costs and the cost of construction products, a technical solution for insulating building structures is proposed. This article analyzes literary sources, both fundamental and modern, covering issues of thermal protection of buildings; factors influencing the payback period of investment energy-saving construction projects; and examples of economic evaluation of energy-saving measures. Heat loss through the roof structure under consideration was calculated. Heat loss graphs were constructed for various «roof – window» combinations. Insulation options were identified, based on regulatory requirements and the criteria for minimizing the amount of work. An economic analysis of the selected options was conducted.

Keywords: heat loss, utility function of thermal insulation, indifference curves, budget equation

 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

This article examines the fundamental principles of the combined critical path method/line of balance (CPM-LOB) method, used in foreign practices for scheduling repetitive construction projects, and the corresponding algorithm for calculating the parameters of heterorhythmic construction flows based on the duration of critical path activities within a single local work front (work unit) and the project-wide deadline. The article identifies the method's key shortcomings and their potential solutions. A modification of the CPM-LOB method, utilizing parallel work by crews on multiple work units within cycles, is presented. A method for coordinating related work performed by crews within cycles, the "Delta-shift" method, is described. Finally, the article assesses the applicability of this method to designing heterorhythmic work flows in domestic scheduling practices for construction, reconstruction, and major repair projects involving buildings and structures.

Keywords: construction organization, flow method, scheduling, flowline chart, network diagram, critical path method, construction work flow, work front, work unit, Delta-shift method

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 article is devoted to the scientific and methodological foundations of the development of compositions of composite materials specifically designed to significantly improve the physical and mechanical properties of substrates and road coverings of highways, various products and structures. The fundamental principles underlying the creation of an optimal structure of composite materials are described in detail, which contributes to a significant increase in strength, reliability and longer service life of structures. In addition, an analysis of modern methods for optimizing the composition of composites is given, special attention is paid to the importance of taking into account the specifics of interphase interactions between components and the distribution of filler particles inside the matrix. Practical approaches are described and examples of successful application of the principles and the potential of the solutions obtained are given. The key role of mathematical modeling and experiments, which are an integral part of effective formulation selection and optimization of composite properties, is highlighted separately. The main provisions of all the methods under consideration are the competent selection of high-quality starting materials, the correct determination of the optimal granulometric composition of the mineral components of mixtures, the accurate calculation of the required amount of binders, as well as strict control over the compliance of the designed characteristics with the planned indicators, which guarantees the receipt of high-quality and reliable substrates and coatings for highways, products and structures.

Keywords: building composites, composition, design, development, technology, modeling, property management, optimization, road clothing

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 article examines the effect of fine dust on the health of those involved in the gym. The factors characterizing dust are investigated depending on the ranges of breathing height of the participants. A series of measurements is carried out in the gym and further examination using a microscope and a personal computer. The results of the dispersed composition of dust are obtained. The dependence of the diameter of the dust particles on the height has been revealed.

Keywords: fine dust, working area, dispersed composition, aerodynamic characteristics, particle diameter, sports hall

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

The article is devoted to the analysis of the typological features of Orthodox churches. This topic is related to the spread of Orthodoxy throughout the world, which prompted the authors to analyze and systematize some of the features of decorative and artistic techniques of temple construction, as well as the canons of Orthodoxy in time, originating from Byzantine architecture.

Keywords: orthodox architecture, temple architecture, typological analysis, semantics of temples, Byzantine style, cross‑domed structure, tent temples, Russian patterned, Naryshkin style, architectural styles, sacred meaning, three-part division, domed completion

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 ongoing and planned comprehensive modernization of the bus station network within a city or region confirms the relevance of this study. Using examples of advanced domestic practices, the specifics of creating and developing transport hubs based on old and new bus stations are examined, criticism from direct users of the environment is analyzed, and domestic approaches are compared with international trends. Two main approaches to the reconstruction or construction of bus stations and the creation of transport hubs at them are identified: municipal facilities with a predominantly transport function, and investment facilities with a predominantly retail and entertainment function. A planar (horizontally developed spatial) organization of transport hubs is established as superior to a compact volume and/or the "dry feet" transfer principle.

Keywords: transport structure architecture, passenger facilities, reconstruction, bus stations, bus terminals,transport interchange complexe, transport hub, multifunctional complex

The article is devoted to researching the transformation of approaches to designing medical facilities for children. The work justifies the transition from traditional functional and hygienic models to a complex paradigm of «health architecture», where space becomes an active participant in the therapeutic process. Based on an analysis of the historical development of approaches to design up to modern concepts of biogenic design - the key principles of formation of an ozone-producing environment have been identified. Special attention is given to the scientific substantiation of therapeutic impact of architectural decisions, confirmed by research in the field of proof design. The result of the study is a set of principles for forming an architectural environment, aimed at creating conditions for physical and psycho-emotional recovery of children. 

Keywords: architecture, health architecture, children’s medical institution, sustainable architecture, biogenic design, therapeutic environment, ecological approach, space psychology, zoning, navigation

This article presents the results of a study of the particle size distribution (PSD) in aqueous suspensions of eight natural and artificial minerals, including gypsum, limestone, marl, shale, anhydrite, dolomite, bentonite, and cement. The analysis was conducted using sedimentation in a particle size range from submicron to hundreds of micrometers, revealing significant differences in distribution depending on the mineralogical composition. A study of the particle size distribution revealed that samples with narrower distributions, such as anhydrite and bentonite, exhibit high stability and predictable kinetic characteristics, while the polymodal distributions of marl and cement suggest their suitability for use as fillers. The obtained data allow us to predict their influence on the properties of binders, including hydration rate, packing density, pozzolanic activity, and tendency to aggregation. The results may be useful for optimizing technological processes in the development of repair and restoration compounds and binders.

Keywords: particle distribution, size, suspension, binders, sedimentation, colloidal stability, repair and restoration compounds, median, distribution width

This article examines the environmental, economic, and technological aspects of using rice husk ash (RHA) in the construction industry. It is shown that the use of this waste from the rice processing industry helps reduce the carbon footprint and improve the quality of cement paste. The results of an experimental study of the effect of RHA on the physical and mechanical properties of cement paste are presented. Patterns of change in setting time, water requirement, strength, and hardening kinetics are established when replacing part of the Portland cement with RHA in quantities of 5, 10, 15, and 20% of the cement mass. It is shown that the optimal content of the additive is 15%, which improves the strength properties of cement paste at the age of 28 days by 10% compared to conventional cement.

Keywords: rice husk ash, Portland cement, cement paste, setting time, water requirement, strength, hardening kinetics, pozzolanic activity

To enhance the performance characteristics of asphalt concrete mixtures in high-temperature conditions typical of hot climates, researchers actively employ various stabilizing additives aimed at increasing the durability of road pavements. One traditional solution is the use of the Sтилобит modifier, which improves the resistance of asphalt concrete to deformations, rutting, and cracking caused by intense traffic loads and climatic factors. However, Sтилобит has several drawbacks, including insufficient binder stability at high temperatures and a limited ability to ensure optimal material density, which can reduce the overall effectiveness of the pavement. These limitations drive the search for more modern and efficient alternatives that can balance quality and cost-effectiveness. Within the scope of this study, a new stabilizing modifier, PROPolymer MA-CK, was evaluated as a promising alternative to Sтилобит. For comparative analysis, two asphalt concrete mixtures were prepared: one with the addition of Sтилобит and the other with PROPolymer MA-CK. Laboratory tests demonstrated that the mixture with PROPolymer MA-CK exhibits improved performance characteristics, including enhanced resistance to rutting, better binder stability, and higher material density, which contributes to reducing the risk of deformations. Thus, PROPolymer MA-CK can be considered a more effective alternative to Sтилобит, providing not only increased reliability and durability of road pavements but also potential cost reductions in the construction and maintenance of roads.

Keywords: Polymer MA-CK, crushed stone-mastic asphalt concrete mixtures, rut, rut formation, performance characteristics, Stylobite, modifiers

The article presents the experience and technology of arranging floors of industrial buildings based on cement mortar containing modified basalt microfiber. Structural solution of floor with coating modified with basalt microfiber is given. Technological operations performed at the facility are indicated. Invention proposes a modified solution mixture composition characterised by improved physical and mechanical characteristics. Prior mechanical separation of the microfibers in suspension with water and plasticizer has been found to promote more uniform distribution of the fibers throughout the solution mixture.The scheme of organization of the workplace when laying fiber reinforced cement mortar mixture in the floor covering structure is presented. It has been found that by introducing modified basalt microfibers into the cement mixture, shrinkage strains of the mortar are reduced, which contributes to increasing the crack resistance of the cement coating. Physical and mechanical characteristics of the modified coating are determined, such as abrasion, compressive strength and bending tensile strength. Improved physical and mechanical characteristics of the modified cement mortar were noted, which makes it possible to use the developed compositions and technology when arranging floors in buildings with increased mechanical effects.

Keywords: monolithic coating, device technology, dispersed reinforcement, concrete, modified basalt microfiber, fiber reinforced coating, mortar mix, floors of industrial buildings

This article analyzes the planning organization of the city of Rostov-on-Don within the framework of implementing the concept of sustainable development and identifies existing spatial and functional imbalances. Dense, mixed-style development, congested transport infrastructure, and uneven distribution of green spaces negatively impact not only the city's environmental status but also the quality of life of the population, necessitating a comprehensive consideration of environmental, spatial, and socioeconomic aspects to optimize urban planning decisions.

Keywords: sustainable development, urban environment, dense urban development, infill development, landscaping and amenity improvement, prospective development of territories

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

Experimental studies have been conducted on a method for obtaining a highly dispersed water-air mixture for flotation wastewater treatment using vortex mixing devices. In the course of experimental studies, the patterns of changes in the circumferential (radial) flow velocities of a single-phase liquid (pure water) in the annular space of the barrel of a vortex mixing device at different diameters of the central rod were determined. Experimental studies were carried out at different heights of the H trunk (0.5 m, 1 m, 1.5 m and 2 m) with and without enamel coating of the flow part

Keywords: flotation, dispersion, vortex mixing device, axial velocity, circumferential velocity, trajectory angle of incidence, enamel coating

This article presents a practical approach to the design of precast concrete frame buildings based on a developed methodology for accounting for the flexibility of joints between floor and roof elements, using a plate-and-rod model of a floor fragment. For two types of braced frames (with symmetrical and asymmetrical stiffener arrangements), an analysis of quantitative indicators of deformability and relative forces is presented, with reduction factors applied to the integral rigidity of the precast floor in its plane, obtained using the proposed methodology. This analysis compares this approach to the classical approach to designing precast frames, taking into account the rigidity of monolithic floors. The results of the calculation of frames using the proposed method show that with a decrease in the rigidity of the floors (reducing to equivalent rigidity, taking into account the flexibility of the seams in the joints of the floors), the vertical forces in the columns from horizontal loads decrease, and the moments in the stiffening diaphragms increase, that is, in the frame structures, both reserves and deficiencies in the bearing capacity can be identified, which is especially important during the inspection and subsequent reconstruction of buildings with the structural system under consideration.

Keywords: multi-story frame structural system, precast floor, flexibility, horizontal load, joint, rod model, equivalent stiffness coefficient