Introduction. Using the example of the Vologda-Arkhangelsk Railway, built in the late 19th century in a previously uninhabited area, this paper examines the historical and urban planning aspects of the characteristics and patterns of the formation and development of settlements at railway stations, creating a new system of regional settlement. The relevance of this topic is determined by the significance of station settlements along the Vologda-Arkhangelsk Railway as historically important elements of the supporting framework of regional settlement. At the same time, the small population of station settlements and the current trend towards further decline leads to their degradation and poses a threat to the stability of the supporting framework in the railway’s zone of influence and the region as a whole. This necessitates research into the history of station settlements with the goal of their sustainable development based on existing historical models, buildings, and context, which will reduce or stop the outflow of population to large cities. The aim of the study is to identify the characteristics and factors of the initial formation of the supporting framework of settlement in the zone of influence of the railway and sustainable trends in the development of its nodal elements — station settlements.

Materials and methods. The study utilizes a historical retrospective method as its primary method, based on identifying and extensively citing sources from the initial formation of station settlements along the Vologda-Arkhangelsk Railway in the early 20th century: archival documents, historical and statistical reports, and scientific and analytical studies. Another set of analyzed materials pertains to modern research on various aspects of the topic, including historical, socioeconomic, architectural, and urban planning. This method allows for the formation of an initial evidence base for further research and an assessment of the dynamics of the process and the underlying principles of the formation of a new settlement system in the railway’s zone of influence from its inception to the present day. The author examined the current state of development along the railway through field studies.

Results. A block of archival materials from the late 19th and early 20th centuries on the construction of railway stations and settlements along the Vologda to Arkhangelsk railway line, as well as analytical studies of this period on the development of adjacent territories, have been identified and introduced into scientific circulation. By analyzing the identified historical materials, key features of the railway’s construction and the development of its station settlements have been identified. These findings have helped us identify the factors that shaped the formation of a new settlement system in the region, one subordinated to the operational requirements of the railway and ignoring existing settlements. The key factors in the formation of a settlement framework in the railway’s zone of influence have been identified by integrating the new planning axis at key points with the historical framework. The sustainable development trends of its key elements — station settlements — are analyzed. It has been established that settlement development trends at these key points are directly dependent on the availability of other communication routes, incorporating them into the region’s historical planning framework. The historical and cultural value of the original railway stations has been established and can be used as a basis for the sustainable development of station settlements based on their heritage.

Conclusions. The identified key factors shaping the settlement framework within the railway’s zone of influence and the sustainable development trends of its key elements — station settlements — can be used in research and solutions to address contemporary spatial development issues in the region and serve as a foundation for implementing currently relevant deurbanization ideas. The historical and cultural significance of the railway’s architectural ensemble serves as the basis for protecting its elements — historic stations — as cultural heritage sites, as well as for developing urban planning regulations that ensure the preservation of their identity.

Introduction. Heavy-duty cranе runway beams experience repeated cyclic alternating loads from crane wheels, which cause significant local stresses in the upper web zone. This results in premature fatigue failure of the beams, specifically the development of cracks in the upper web zone, which is recorded during inspections. One of the reasons for such early exhaustion of the beams’ service life may be an incorrect assessment of the stresses in the beam web during design. Analysis and refinement of engineering methods for determining the stress-strain state of the web is a pressing issue, addressed in this paper.

Materials and methods. The results of a theoretical study of the stress-strain state of the upper zone of the web of welded crane beams based on finite element modeling are presented. A comparison of the finite element calculation results with the data from experimental tests of crane beams conducted in 1959 by A.A. Apalko is presented. An analytical determination of the stresses in the welded crane beam webs was performed using various methods, including those of Russian and European standards.

Results. The components of local stresses in the web were determined. The influence of the rail fastening method (bolted or welded) on the stress distribution in the web was studied. Russian standard SP 16.13330.2017 underestimates the stresses in the web due to the local torque by 28 to 68 %. This underestimation of stresses leads to a reduction in the service life of crane beams due to the fatigue cracks in the web. Good convergence with the finite element analysis is achieved by calculating stresses using the A.A. Apalko formula and the European standard EN 1993-6:2007.

Conclusions. The regulatory methodology for calculation of the normal stresses due to local torque in the web of welded crane beams requires clarification. Besides there is a need to develop recommendations for calculating stresses in the webs of beams with a bolted flange-to-web connection. Crane beams with High-Strength Friction Grip (HSFG) bolted connections provide higher efficiency and longer service life compared to welded beams. The lack of calculation methods limits the use of such beams.

Introduction. Billions of rubles are invested annually in the restoration of concrete structures, as traditional repair methods require re-strengthening on average every 3 years. This study explores the potential of biotechnologies using Bacillus pseudofirmus bacteria and Trichoderma fungal spores, which are capable of precipitating calcium carbonate (CaCO3) and healing cracks in concrete during their metabolic processes. However, current methods of microbial encapsulation to maintain viability in the highly alkaline environment of concrete limit the widespread implementation of these approaches. The aim of this study is to develop a carbonate biomineralization technology using Trichoderma fungal spores for the self-healing and reinforcement of existing concrete structures.

Materials and methods. Theoretical methods were utilized to analyze microorganisms capable of CaCO3 biomineralization, while empirical methods were employed to develop a nutrient substrate that supports mycelium growth at pH 11–13 and to test its application for concrete reinforcement.

Results. The carbonate biomineralization technology was developed, facilitating concrete self-healing by immersion in a substrate based on coconut coir, sawdust, blue clay, wood ash, dolomite flour, and Trichoderma harzianum spores in a ratio of 40:40:5:5:5:5 %. This composition demonstrated high adhesion to the surface of the specimens and ensured the formation of a stable limestone-mycelium framework. As a result, a two-fold increase in the compressive strength of the concrete from 21 to 42 MPa was achieved within 28 days without external technological intervention.

Conclusions. This technology represents a promising alternative to traditional injection methods and polymer-based repairs, potentially preventing the premature degradation of concrete structures and contributing to the development of environmentally friendly and efficient infrastructure healing methods.

Introduction. The results of studying the properties of cement composites based on Portland cement obtained using a complex bioadditive consisting of two strains of the genus Bacillus are presented. The use of special bioadditives with urease microorganisms makes it possible to improve a number of properties of cement composites due to the formation of calcium carbonate in the pores of the composite.

Materials and methods. Portland cement of the following grades was used as a binder: CEM I 32.5 N, CEM II/B-W 32.5 N, CEM III/A 32.5 N. The active agent in the supplement was a mixture of Bacillus licheniformis and Bacillus subtilis strains. The combined dietary supplement was made using the “inclusion in gel” method using a 1 % solution of calcium alginate. The granules of the finished dietary supplement were dried and stored at a temperature of no more than 30 °C and a humidity of no more than 50 %.

Results. Optimal compositions of concrete mixtures modified with a complex bioadditive were developed, and the physico-mechanical properties of the obtained cement composites were evaluated according to the following indicators: workability, water resistance, strength, and frost resistance. It has been established that the use of a complex bioadditive has a positive effect on the physical and technical properties of modified concretes. The modified concrete specimens showed increased compressive strength by more than 10–12 % on day 28, 25–26 % on day 56, and 36–38 % on day 112th, compared with control specimens of the same age, respectively.

Conclusions. The results obtained indicate that the use of a complex bioadditive significantly improves the construction and technical properties of concretes made using various types of Portland cement compared to control specimens. The modified specimens exhibit increased compressive strength and frost resistance (F500 and higher), and the filtration coefficient has decreased by more than 15 %.

Introduction. The paper is devoted to the digitalization of the industry and the safety of construction. The urban economy includes systems, for example, water supply and sanitation, HVAC and others, the reliability and stability of which are closely related to the level of cybersecurity. In the context of digitalization and the widespread adoption of BIM and automated process control systems, the level of their exposure to cyber threats is significantly increasing. Traditional approaches to security are not effective enough. The practical application of quantum communications and artificial intelligence methods in the field of cybersecurity remains poorly understood. The purpose of this study is to analyze the potential of using quantum technologies and artificial intelligence methods to improve the cybersecurity of BIM and automated process control systems, as well as to assess the prospects for implementing solutions to protect critical infrastructure.

Materials and methods. The work uses methods of system analysis, modelling of cybersecurity architectures, as well as machine learning methods to identify anomalies in network traffic and telemetry of BIM and automated process control systems. The technology of quantum key distribution, which provides physically guaranteed confidentiality of communication channels, is considered as a cryptographic basis.

Results. A hybrid architecture of BIM and automated process control systems cyber defense technologies is proposed, combining quantum technologies to protect communications and intelligent monitoring based on machine learning to detect abnormal behavior. It is shown that the integration of quantum networks with AI can significantly increase the stability of the system, as well as reduce the time for incident detection.

Conclusions. The results of the study confirm the prospects for the joint use of quantum communications and artificial intelligence to protect BIM, automated process control systems. The proposed approach can be used in the design of cybersecurity systems and serves as the basis for further research in this area.

Introduction. The developing eastern regions of Russia lie within the permafrost zone, characterized by severe climatic conditions. Hydraulic structures supply facilities and settlements with electric power and water. Mining and metallurgical enterprises require waste storage facilities complying with environmental regulations. These tasks are solved by constructing earth hydraulic structures: soil dams, flood-protection dikes, and storage dikes. Emergency situations are most often caused by disturbances in the thermal–seepage regime, whose prediction remains a complex task.

Materials and methods. The thermal regime of a homogeneous soil dam under subzero temperatures was analyzed numerically. A coupled thermal–seepage problem was solved for four variants depending on the physical processes considered: seepage flow in the dam body, phase transitions of water, and the time-dependent temperature boundary condition. Analyses were performed using the finite element method in PLAXIS 2D. The influence of each factor on thermal behaviour of the structure was examined.

Results. Temperature field distributions were obtained for the domain comprising the soil dam and its foundation. Temperature–time curves for selected points along the dam profile revealed the extent to which seepage and phase transitions affect the thermal regime of the structure.

Conclusions. Seepage flow through the pore space of the soil significantly affects the rate of heat penetration and the extent of the thawed zone within the upstream prism of the dam. Accounting for water phase transitions slows the thawing of the structure under heat flux from the reservoir. The methodology for calculating the thermal–seepage regime of soil structures requires further refinement and development.

Introduction. The transients that occur during the regulation of the climate control system are characterized by a change in the parameters of the air flow over time. The derived value of these parameters is the heat absorbed by the system elements from the stream or released by them into the stream. For interpretation and general analysis of experimental data, relatively excessive heat is proposed as the main parameter, showing the dynamics of its change relative to a previously established thermal balance. The analysis of changes in relative excess heat at a constant heating capacity of the air heater from two stepwise sequential changes in fan performance is carried out.

Materials and methods. The method of studying transients in a humid air stream is based on conducting an experiment in field conditions. Changes in the parameters of the air heater and fan during the control process were recorded after one second. The system under study was considered as a system with concentrated parameters.

Results. The results of identification of transient processes based on the use of relatively excessive heat are presented.

Conclusions. It is established that the air “heater – fan – room” system with two stepwise sequential changes in fan performance is a linear system for which the conditions of homogeneity, additivity, invariance, and harmonic fidelity are fulfilled.

Introduction. The prediction of the indoor air temperature in a building during the cold season in the event of an emergency disruption of the centralized heating system is directly related to the safety of people’s lives and building structures. The relevance of this research lies in the development of a new cooling equation that allows for the consideration of the cooling of
indoor air separately from the building’s envelope. In contrast, existing calculation formulas consider the cooling process of a building to be regular over an entire time interval, and the air and building envelope are treated as a single entity. The study focuses on a typical room on a typical floor in a multi-story residential building.

Materials and methods. The results of the cooling task after an emergency shutdown of the heat supply were obtained in three ways: using a numerical calculation method based on the equations of non-stationary thermal conductivity and non-stationary thermal balance of the room air; using the classical exponential cooling equation by E.Ya. Sokolov and V.N. Bogoslovsky; and using a new formula developed by the authors.

Results. A new formula for calculating the cooling of indoor air separately from the building envelope has been developed and verified. The process of blocking the accumulated heat in the building’s internal walls during the initial cooling stage, with varying levels of non-inertial heat loss, has been examined, confirming the need to account for the room’s radiant temperature in the classical cooling equation. A comparative analysis of the cooling time results obtained using three different calculation methods has been conducted. Graphs showing the temperature changes in the indoor air of the study room during the cooling period of up to 2 hours and up to 54 hours have been presented.

Conclusions. The error of the obtained method relative to the numerical solution and the classical cooling equation is less than 1 °C both in the short cooling period of up to 2 hours and in the long cooling period of up to 54 hours.

Introduction. This paper examines the problem of taking into account complex climate impacts when determining the effective outdoor air temperature in Arctic regions during the winter. A comparative analysis of climatic factors for several settlements located in the Far North is conducted. It is shown that traditional approaches to calculating building thermal insulation may be insufficient for the extreme climatic conditions of the Arctic. It is proposed to consider complex climatic factors — the duration of low-temperature periods and wind exposure — when determining the effective outdoor air temperature in winter.

Materials and methods. The study utilized current regulatory documents governing thermal insulation requirements for building envelopes and structures. Official weather station data were used to analyze the climate parameters of cities in the Far North.

Results. The analysis showed that in some Arctic regions, effective outdoor air temperatures can be 6–8 °C lower than the standard “cold five-day period” t50.92. The greatest discrepancy is observed in areas with high wind speeds (Anadyr, Norilsk), where the average winter wind speed exceeds 7 m/s, and the number of days per year with prolonged wind exposure is 120 or more. In cities located in the influence zone of the Siberian anticyclone (Yakutsk, Verkhoyansk), the wind effect is insignificant.

Conclusions. The main limitation of traditional calculation methods for designing thermal insulation for buildings is the lack of consideration of combined climatic impacts. This necessitates a transition to a multiparameter model for individual regions that takes into account the combined impact of subzero temperatures and wind speeds when designing thermal insulation for buildings and structures, as well as the development of regional standards that take into account the specific climatic parameters of the Far North.

Introduction. More than 6,000 scientific papers on the topic of lean construction by Russian and foreign scientists, reflected in the bibliographic catalog of scientific works OpenAlex, were analyzed, basic tools of lean construction offered in educational and scientific publications were considered, and available data on the application of lean technology in large construction projects of residential and industrial infrastructure were used, including the historical case of the construction of the fourth power unit of the Kalinin NPP.

Materials and methods. The theoretical framework was based on works in the field of energy conservation management, applied statistics, and econometric modeling. The information base consisted of hypothetical data for testing the tools. Three models were used: statistical (based on a normal distribution and Z-scores), robust (based on quartiles and interquartile range), and regression (multiple regression analysis taking into account predictor factors).

Results. The selection of specific energy consumption as the standardized indicator was substantiated. A sequence of standardization stages was developed: collecting and cleaning data to remove emissions, grouping enterprises by OKVED-2 codes, applying mathematical models, and systematizing and approving standards. The models were tested using hypothetical data from twenty oil refineries. Comparative analysis confirmed that the choice of a specific standardization method should be determined by the goals of regulation, specimen size, and availability of factor characteristics.

Conclusions. The proposed set of models enables objective differentiation of standards based on regulatory objectives and data volume and quality. The statistical model is applicable at the initial stages, the robust model is resistant to outliers, and the regression model allows for individualization of standards. The practical significance lies in creating a basis for enterprise ranking, informed investment prioritization, and systemic industrial modernization. Adapting this approach to machine learning methods is a promising direction.

Introduction. The paper examines the evolution of lean construction with an emphasis on its organizational and economic content and its role in improving the performance of construction organizations. The relevance of the topic stems from cost growth, schedule overruns, resource intensity, and the need to increase labour productivity and management quality in construction. Particular attention is paid to the debate on whether lean construction should be treated as a set of local tools or as an integrated management system focused on cost, time, and value creation.

Materials and methods. The methodological framework combines systems, historiographic, comparative, and content analysis with an organizational and economic interpretation of lean implementation effects in terms of waste reduction, labour productivity, schedule reliability, quality, and resource utilization. The study relies on classical lean production works and current research in construction economics and management.

Results. The key stages in the evolution of lean construction are identified; its content is clarified as an organizational and economic model of construction management; and a classification of approaches is proposed according to their dominant mechanism of influence on the economic results of construction organizations. The paper shows that lean construction contributes to lower transaction and production losses, higher labour productivity, better schedule predictability, and improved quality of project delivery.

Conclusions. Lean construction is substantiated as a research object fully relevant to construction economics and management, since it functions as a tool for improving sectoral efficiency, competitiveness, and the investment sustainability of construction organizations. The practical value of the study lies in the possibility of using the proposed periodization and classification when designing organizational development and labour-productivity programs in construction.