Incremental costs associated with construction works during winter periods are considered in relation to the new calculation method implemented by the Order of the Ministry of Construction, Housing and Utilities of the Russian Federation of May 25, 2021, No 325/pr, instead of the previously used methods specified in the ГСН 81-05-02-2007 “Collection of estimation standards for additional costs during execution of construction and installation works in winter periods” and ГСНр 81-05-022001 “Collection of estimation standards for additional costs during execution of construction and repair works in winter periods”. The research was conducted using the methods of economic and statistical analysis, review of theoretical and practical materials, as well as the system approach. The conditions determining the impact of negative temperatures on construction and repair works are analyzed and classified. The costs associated with temporary heating of facilities completed within the heating period are analyzed. On the basis of the results obtained, directions for improving calculations of incremental costs when executing construction and installation works in winter periods are proposed with the purpose of optimizing costs of construction objects.

A methodology for identifying sections in water supply and distribution systems (WSDSs) that inhibit high-quality water supply is proposed. The study is based on the previously developed mathematical models of water withdrawal (cross-sectional method) and flow distribution. Effective WSDS management requires not only consideration of water withdrawal patterns from WSDSs and probabilistic structural variations, but also assessment of the impact of individual components (sections) and their weight contribution on the system performance. During the analysis, K_j and P_j probabilistic reliability indicators of water supply to consumers were used. These indicators include the following components: probabilities supplying water to consumers in these states. The reliability of consumer supply in each state is assessed using partial indicators K_j ⁱ and P_j ⁱ. Conclusions about the operational quality of each section can be made by comparing partial indicators with normalized values. Using partial indicators obtained in structural states, it is possible to assess the overburden of sections and their importance for ensuring the necessary quality of consumer supply, as well as to evaluate their backup line operation. An example of a particular system is used to demonstrate all steps of the proposed methodology. The need to use the previously developed software application for analysing the WSDS operation is justified. The software allows partial reliability indicators K_j ⁱ and P_j ⁱ to be determined for each structural state of the system. The proposed methodology for identifying WSDS sections with a capacity inhibiting reliable water supply can be used when designing new or surveying existing WSDSs.

The aim was to investigate the prospects and possibilities of using nanotechnologies and nanomaterials in construction, particularly in concrete production. The research methodology involved a set of methods and principles of scientific cognition, as well as general and specific methods and techniques, such as comparative analysis, modelling, classification, grouping, generalization and forecasting. The authors propose a method of concrete production using a matter with a specified atomic structure. It was established that the consideration of atoms and microparticles can increase the efficiency of concrete production. In addition, special attention is paid to a nanoparticle as the structural unit of nanotechnology. Nanoparticles are capable of changing the colour of artificial coatings, increasing the wear resistance of materials and improving their resistance indicators. In innovative technologies, reinforced steel, composite reinforcement and nanocoatings are used. In addition, detailed information is provided on structural composites having a ceramic, iron or polymer matrix. A particular emphasis is placed on the advantages of nanoconcrete. Nanoconcrete represents a whole group of materials that can impart the desired characteristics to products and structures. Expanding the use of nanotechnology in construction implies the need for an interdisciplinary and multidimensional approach for further research and development, including such fields as civil engineering, materials science, physics and other related disciplines.

Possible approaches to reducing the fire hazard in private housing construction are considered. The study was conducted using general scientific methods, including network analysis, numerical analysis and the methods of visualisation using Matlab graphic editor. The current state of housing construction in the Russian Federation and, in particular, Baikal region, is analysed. It was established that, due to the implementation of national projects, the level of private housing construction has increased considerably in recent years. At the same time, the use of wooden structures, which are exposed to increased threat of fire hazards, is gaining in popularity. An analysis of fire hazard in Irkutsk Oblast revealed that one of the most probable causes of ignition is associated with the violation of rules for arrangement and operation of electricity-generating equipment. The most common cause of such violations was proved to be the asymmetry of phase currents, which causes additional heat losses contributing to the occurrence of fires. The effectiveness of balancing devices in reducing the consequences of asymmetric power consumption was confirmed on a specific example. The implementation of measures to balance the operating modes of internal electrical networks of residential buildings represents one of the most effective ways to reduce fire risks in private residential buildings. Based on the obtained results, a set of recommendations is proposed for use by specialists of construction organizations, as well as employees of the Ministry of Emergency Situations controlling the fire safety of individual residential buildings.

An experimental-probabilistic analysis of variations in the load-bearing capacity of bending reinforced concrete elements with matrices reinforced by polypropylene fibres was carried out. A numerical experiment was conducted using the normative methodology of multi-link and layerwise modelling of element cross-sections and experimental "σ-ε" diagrams of fibrocomposites in initial and post-cyclic (50 cycles with ɳ = 0.8 amplitude and zero asymmetry) states. Probabilistic changes in the loadbearing capacity of bending elements subjected to cyclic loads were estimated by the numerical strength modelling of rectangular beams (b x h = 100 х 200 mm) with the one-sided reinforcement (A400 class) of varying intensity. The observed high value of fatigue life of reinforced concrete elements with fibre-reinforced matrices was found to be associated with the presence of mechanisms compensatory for structural changes, i.e., a decrease in the strength is accompanied by an increase in the ability to redistribute internal forces. A post-cyclic reduction in the strength of concrete causes practically no effect on the load-bearing capacity of bending elements with a large and economically preferable range of their structural reinforcement. The reliability kinetics of elements, estimated by the level of the realised concrete strength potential, was analysed. Moderate (μ < μ_R) reinforcement was found to result in objective conditions for increasing the completeness of the stress diagram in the compressed cross-sectional part due to the redistribution of forces along the height. In this case, despite a significant decrease in the strength of concrete, the load-bearing capacity of elements at μ ≤ 2.5% reinforcement remains practically the same after cyclic effects.

The practice of operation of gravity sewer networks of domestic wastewater shows that sediment deposits are formed in the chute section of pipes at certain velocities of the gravity flow. These deposits affect the hydraulic characteristics of the flow, which depend on the actual thickness of the sediment layer in sewer pipes. In this study, a velocity diagram reflecting the distribution of actual velocity values of wastewater flow along the depth of the wetted perimeter of pipes with sediment deposits in their chute sections is established. To this end, the dependences derived by the authors previously for hydraulic calculation of drainage networks with internal sediments were used. It is confirmed on a specific example that the limiting value of sediment thickness preventing the continuation of further operation for concrete pipes with a diameter of 400 mm equals 80 mm. The obtained diagram of the vertical velocity distribution of sewage flow can be used to determine the actual pipeline fill level corresponding to the actual sediment layer thickness in sewer pipes.

The development of low-rise housing construction is a key priority in the Russian Federation due to its potential to increase the total volume of housing construction. An increase in the share of this type of construction is a goal set in federal programmes and projects in the field of housing policy. At the same time, in order to make low-rise housing more popular among the population, its constructional stages should be optimized both at the operational and technological levels. In this regard, the study is aimed at updating methodological approaches to the organization of low-rise housing construction by identifying critical points in the operational processes of construction works. The study was conducted using the methods of system analysis and empirical research. Relevant research publications by Russian and foreign scientists on the topic were reviewed. The sequence of processes in low-rise housing construction is considered with a detailed description of each stage. The analysis of the distinguished stages allowed the authors to identify critical points and possible deviations, as well as the causes of deviations and possible preventive measures. Strategies for improving the quality of construction works are proposed. The determination of critical points and development of managerial strategies can ensure the effectiveness of the organisational mechanism applied during the implementation of low-rise housing projects for developers.

Real structural elements exhibit various nonlinear properties, which are most significantly manifested during intensive dynamic processes. The deviation of mechanical characteristics from the linear ones adopted in idealised models, for which the problem of eigenvalues is solved, can lead to unacceptable calculation errors or completely false results. For this reason, the accuracy and applicability of linear models and resulting methods based on solving problems of eigenvalues remain an open question. The study is aimed at the analysis of errors associated with the application of spectral methods in “best” approximations of nonlinear characteristics by linear dependences, obtained on the basis of root-mean-square approximations, which prevent superfluous doubts about the result formation. A dynamic model of an unsupported beam with two concentrated masses oscillating in directions perpendicular to the stiffness axis was considered. For the linear model, the accuracy of approximating the initial nonlinear stiffness was assessed by comparing the amplitude displacement values and velocities of the system at the linearized and initial stiffness. In addition, a comparison of the above linearization method with the linearization by a zero first derivative of the nonlinear stiffness function is considered. The discrepancies in the results represent the functions of initial conditions. The limit values of deviations at the maximum point of the function, describing the nonlinearity of stiffness, comprised 2.02 and 10.55% for the methods of standard deviation and zero first derivative, respectively. The obtained results require clarification with regard to structural systems used in construction practice.

In this work, a theoretical basis for a comprehensive assessment of the environmental hazard of wastes, which are formed during the functioning of critical infrastructure in residential territories, is developed. In addition, a resource-saving (resource-recovering) system is proposed for ensuring the protection of natural environment and vitally important human interests from the anthropogenic impact of wastes, thus creating favourable conditions for the vital activity of a population. The study was conducted using mathematical methods, such as mathematical logic and vector algebra, for assessing the system of an ecologically safe critical infrastructure of populated areas. It is argued that the formation of a resource-saving system, which does not include wastes as its constituent element, provides the integrity of a closed material-raw cycle. Moreover, such a system reduces the formation of waste material masses (sources of environmental hazard) as a quantitative result of the system to zero. It is shown that environmental hazards in residential areas can be prevented in those places, where a system of processing construction and other products at the last life cycle stage as secondary resources is implemented and no hazardous wastes are forwarded for disposal in the natural environment. The obtained results can be used when assessing the environmental safety of concepts, strategies, programmes and projects at federal, regional and sectoral levels in the field of resource saving, waste and secondary resources management, as well as for ensuring the environmental safety of residential areas.

In this study, we examine a contemporary church building as a powerful symbol of cultural and architectural identity of a city. The city space organized around and inside a religious building is considered as an important public space from the perspective of civilizational culture. During the study, a comparative analysis of European and Russian contemporary sacral construction was carried out with the purpose of forecasting the development of the present Orthodox architecture, taking into account possible trends, styles and directions. A field survey of 150 contemporary churches in Austria was carried out. Their evolutionary development over the past 120 years was examined both empirically and using scientific literature. In addition, a number of Russian churches, including restored or renovated historical buildings as well as new facilities built after the collapse of the USSR, were studied. As a result, an assessment and explanation of the inevitable appearance of modern trends in the Orthodox Church architecture is given. Historicisms, existing in the Orthodox architecture of our time, are assumed to be related to the forced 70-year pause in the development of Orthodox architecture, rather than to the greater conservatism of the Orthodox religion. Any architecture, even its conservative religious type, responds to events occurring in a society and to arising new cultural and functional needs. As a result, due to a competent interaction of architects and customers, the existing architectural style starts to change gradually in terms of its spatial organization, form, composition, general appearance of the inner and outer space, thus giving rise to new symbols of cultural and architectural identity. With the addition of new functions, a church remains to be a unique public building, forming public urban spaces both in and around itself.

This study continues the author's article series aimed at examining the territory of garage cooperatives (GCs) in Irkutsk as prospective development areas and reserves of urban lands. The “garage amnesty” law accepted by the State Duma of the Russian Federation provides the citizens with the possibility to legalise their garages and land plots, which makes the integrated development of GCs highly specific. The study analyses territories of the most valuable landscapes in the southern part of the Sverdlovsk Okrug occupied with GCs, which impede their integrated development. An empirical research method was used, including a description, comparison by districts and calculation of actual GC areas formed by 2021 in Irkutsk. An analysis of the GC location was carried out with the provision of absolute and relative indicators. In the process of the study, a strategy for improving the quality of the living environment by transforming the areas of garage cooperatives into attractive recreational zones with highly effective multifunctional facilities was developed. This strategy proposes a compact storage of cars, their maintenance, arrangement of individual vegetable storages and organisation of other public functions at the places of GC location with the transformation of the latter into a comfortable environment both for owners of personal vehicles and neighbourhood residents. GC territories can be transformed into potential sites of city development. The paper contains schemes and research results obtained in the framework of the final qualification work in the "Architecture" speciality of student M.V. Malkina (2021) under the guidance of the author of the present article at the Irkutsk National Research Technical University (INRTU).

The Siberian fortifications of the 17-18th centuries represent an important part of Russian wooden architecture, significant both for world and local histories of the development of wooden architecture. The identification of specific architectural and construction approaches used to erect fortresses during the epoch of the accession of Siberia to Russia, namely the East Siberia and the Amur Region, is essential for studying the main principles of establishing ostrogs (fortresses) and settlements. The study is aimed at clarifying the meaning of such architectural and construction terms of Russian wooden fortification architecture as “gorodnya” and “nagorodnya”, which are encountered in historical sources of the 17th century compiled by Russian explorers and fortress builders. The following research methods were used: systemic approach, analogic method and complex approach with the application of architectural 3D markers representing the units of specific historico-architectural and town-building information, which were preserved in the data about the studied object. Textual, graphic and archaeological materials were used. The main results included the widening of "gorodnya" and "nagorodnya" architectural and construction terms of the 17—18th centuries, as well as the graphic reconstruction of Albazino Ostrog walls in accordance with new scientific data. Despite the fact that options for the reconstruction of such fortress walls have been proposed previously, the clarifications in this work are more objective. The obtained results can be used for a more precise organisation of historical, architectural, town-building and archaeological works, as well as in restoration and reconstruction processes.

The development directions and formation features of contemporary urban parks in China are investigated by reviewing the current news and information sources as well as scientific publications on the principles of contemporary urban park development in China. The study reveals main trends in the development of contemporary urban parks under the influence of the human factor. Thus, in recent years, city residents have increasingly favoured diversified urban ecological parks. Traditional urban ecological parks no longer correspond to contemporary ideas about the high quality of life, making diversification the only way to meet the needs of residents. In accordance with this trend, the design of contemporary urban ecological parks will develop towards diversification and humanization. Although the number of urban parks in mainland China increased significantly between 1980 and 2020, this number is still insufficient to maintain the necessary level of the physical activity of residents. The low number of parks per 10,000 residents, as compared to the US and Japan urban park systems, can lead to the problem of accessibility of public park services. Concerns about spatial inequality are also evident across provinces, city classes and individual cities. In accordance with the policy of prioritized urbanization, inequality is expected to grow unless preventive measures are taken.

The historical and architectural heritage of St. Petersburg dacha (summer residence) as part of Russia's cultural heritage was studied. The research methods included on-site inspections and architectural measurements, photo-fixation of studied objects, archive and museum search, historico-bibliographical search in the repositories of rare ancient books and cartographic divisions of scientific libraries. As a result, the phenomenon of "dacha recreation" was studied. Specific features of the St. Petersburg dacha environment were revealed. On the one hand, the dacha environment is associated with the traditions of spatial organisation of cities and rural settlements in Russia. On the other, the dacha environment is characterised by originality and the absence of a rigid hierarchy in its planning and composition, with the natural environment representing the major formative factor. The determined periodisation of dacha construction included the 1703-1830s, 1830s-early 1860s, 1860s-1890s and 1890s-1917 periods. Areas of active dacha construction were revealed. Thus, dacha construction in the St. Petersburg province was performed predominantly along highways, waterways, railroads and coastline of the Gulf of Finland. A typology of dacha settlements was proposed, including dacha suburbs, dacha villages, dacha resorts and dacha settlements. These types were differentiated in terms of size and population, title and organisation of living activities, type of foundation and administrative status, as well as principles of 3D-planning structure. Particular attention is paid to the unique historical and architectural value of dacha settlements of the St. Petersburg province and importance of its exploration and preservation. It is proposed to use the traditions of creating highly-artistic and optimally-organised dacha recreation environments during the design of contemporary suburban recreational spaces.