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Introduction. The management of urban planning in Russia has been significantly transformed over the 20 years of the Urban Planning Code. On the one hand, vast experience has been accumulated, territorial planning and urban zoning have covered the entire country, on the other hand, an increasing number of documents give rise to new conflicts, decisions are often not synchronized and even contradictory. It is possible to improve the quality of management decisions by building goal-setting, formalizing the tasks of managing the development of territories and systemic transformation in the ways of making management decisions based on the results of urban planning design. The purpose of the paper is to substantiate and formulate arguments in favour of integrated urban planning as an intellectual basis for effective management of spatial changes in urbanized territories.Materials and methods. The study was conducted on the basis of a comparative analysis of complex urban development projects developed under the guidance of the author of the paper in cities of various regions of Russia and the impact of their decisions on the quality of management and the effectiveness of territorial development.Results. The transformations of types of town-planning documentation were substantiated, their composition and content were determined in order to optimize management processes and improve the quality of decisions that ensure the achievement of the goal of integrated socio-economic and spatial development of territories due to the completeness, relevance and legal significance of data on the objects of town-planning planning and town-planning regulation — the results of town-planning design. Urban planning is an intellectual basis for making scientifically sound decisions on the spatial development of urbanized territories.Conclusions. The field of urban planning is expanding significantly. To ensure systematic and effective management of the development of territories, five types of urban planning documentation are proposed, the results of which together will constitute the intellectual basis of the spatial development management system in the format of a digital information model for managing the development of territories: strategic plan; comprehensive infrastructure and investment plan; master plan for land use and development; master plan (strategic, sectoral or local); the project of planning and surveying the territory.

Introduction. The paper proposes a method of accounting for energy dissipation for the Timoshenko beam by constructing a damping matrix based on a modified Rayleigh function in the numerical solution of the problem. In this modification, the velocity of displacements is replaced by the velocities of linear and angular deformations. This approach allows us to take into account energy dissipation due to internal friction in the material when both its volume and shape change. The presented technique is promising in practical calculations of structures when shear stiffness has a significant impact on their stress-strain state.Materials and methods. Several proven methods of energy dissipation accounting are considered, including those that make it possible to take into account the energy loss of a moving structure during friction with the external environment (external damping) and dissipation due to friction in the material of the structure deformed in motion (internal damping). Methods for determining the damping coefficients for each of them are presented. The finite element method is used to calculate rod systems. Damping matrices are derived from the condition of stationarity of the total energy of deformation of a mechanical system in motion, including linear and angular deformation rates.Results. Damping matrices proportional to strain rates obtained on the basis of the modified dissipative Rayleigh function are given. A method for determining the damping coefficient taking into account the rates of angular deformation is proposed.Conclusions. The damping matrices presented in the paper describe the energy dissipation during vibrations of mechanical systems due to internal friction in the material. The internal damping matrix was obtained taking into account the influence of linear and angular deformation rates to simulate the dynamic behaviour of short bending structural elements, the deformation of which is described using the Timoshenko model. The performed dimensional check additionally confirms the correctness of the damping matrix construction. Moreover, the dimension of the proposed shear damping coefficient is the same as that of the widely used viscosity coefficient.

Introduction. Computational studies of aerodynamic interference of the MIBC “Moscow-City” complex with sequential construction of buildings, taking into account their chronological order are carried out. Previous studies only considered the designed buildings and structures, along with the surrounding actual and future development, without computational analysis of their impact on the already constructed buildings. The study demonstrates the importance of considering aerodynamic interference in numerical simulation. It draws conclusions on the mutual influence of high-rise buildings and identifies the wind attack angles that contribute to the maximum values of the average and pulsation components of the wind action.Materials and methods. Numerical simulation methods in the ANSYS Fluent software package were used to conduct computational analysis. Quasi-two-dimensional aerodynamic models of the building complex of MIBC “Moscow-City” were developed, verified and validated for the computational studies.Results. The paper presents the results of 256 design cases, including 13 design variants for the consecutive erection of buildings in the MIBC “Moscow-City” complex and 19 calculations of freestanding high-rise buildings. Each calculation was performed for eight wind attack directions. The paper provides the average and pulsation total aerodynamic forces and moments for each building of the complex, depending on the chronology of building construction. The radar charts of aerodynamic coefficients (average and pulsation) were used to determine the most dangerous wind directions. The number of constructed buildings in the MIBC “Moscow-City” complex was taken into account.Conclusions. Based on the example of the sequential construction of the MIBC “Moscow-City” complex, this study emphasizes the importance of considering aerodynamic interference in dense and changing urban environments for both new and existing buildings. Aerodynamic interference can result in both wind shielding effects and increased wind, which affects the mechanical safety of buildings and structures.

Introduction. The purpose of this paper is to study the main cultural approaches to the process of designing small architectural forms made of metal.Materials and methods. They are determined by the set goals and objectives. Methods of comparative (diachronic and synchronous) analysis, various methods of observation of modern cultural processes and phenomena were used. During the work on the paper, a significant amount of empirical data was analyzed, including the work of contemporary metal artists.Results. Understanding cultural processes and phenomena will allow to develop modern design of small architectural forms made of metal, to use the ideas of the paper in the educational and creative process. Art metal, one of its three main directions — architectural metal, small architectural forms occupy an important place in the formation of a single value-semantic architectural landscape of a modern city. The redundancy of space and time inherent in our present leads to an increase in the number of “non-places” (where there is no place for an individual) in the urban landscape. The space of “No place” is undefinable — neither through identity, nor through communication, nor through historical parallels. Small architectural forms (SAF) help to master “non-places” artistically (meaningfully), turn them into “places” of power, and fill the landscape with meaning. Development of “non-places” by means of designing SAF made of metal becomes an important task for a modern author.Conclusions. Further development of the design of small architectural forms in the XXI century, as well as culture in general, is associated with increasing mobility, built-up communication system and developed information field. Art metal, as one of the most ancient occupations of mankind, preserves invaluable heritage and experience of the past, and within the framework of modern art culture initiates the creation of innovations based on new materials and approaches, contributing to the development of creative thinking and creative freedom.

Introduction. The paper discusses the advantages and features of the main existing methods of connecting wooden columns and crossbars.Materials and methods. It was proposed to increase the load-bearing capacity and reduce the deformability of joints by modifying the joints with the introduction of epoxy resin between the screw and the wood and between the overlay and the end of the wooden element to which it is attached and modifying the design of the overlays.Results. As a result, a constructive solution for connecting wooden columns and crossbars was developed, which has increased reliability compared to the studied connections and is free of their disadvantages. This result was achieved due to the presence of an adhesive layer between the screw and the wood, as well as between the overlay and the wooden element, the making of notches on the sides of the overlays attached to the wooden elements, the increased length of the screws screwed into the overlay with a groove, compared to the length of the screws screwed into an overlay with a tenon, placement of holes for screws at an angle of 90° to the surface of the overlay into which the screws are screwed.Conclusions. An urgent issue is the development of constructive solutions for connections of wooden elements, in particular the interfaces of columns and crossbars. The paper discusses the advantages and features of the main existing methods of connecting wooden columns and crossbars.

Introduction. The sustainability of territories of urban settlements (USs) and rural settlements (RSs) is one of the priority tasks of urban planning and socio-economic planning, and is also determined by the goal of integrated development of the territory. This issue is widely discussed in the scientific and technical literature, where the focus is on socio-economic, environmental and anthropogenic factors that characterize the urban system, which are used to obtain a quantitative indicator of the level of sustainability using entropy-weighted, (TOPSIS-Technique of Preference Similarity to the Ideal Solution) and other methods. At the same time, the importance of cultural heritage in sustainable development has not received enough attention. This paper presents the results of sustainability assessment of the impact of immovable tangible cultural heritage of eight Syrian cities based on a multi-criteria model.Materials and methods. The paper uses materials from open sources and statistical data of municipal organizations, the selection of which is based on the Sustainable Development Goals (SDGs) and the system approach. The data include characteristics of social, historical-cultural, economic, environmental, engineering, transport subsystems of the city. The aim of the study is to determine a generalized index characterizing the sustainability of the city and the impact of its factors on its importance of cultural heritage in promoting socio-economic development and urban reconstruction after the military conflict.Results. Based on the presented model, calculations of the urban sustainability index (IS) of 8 Syrian cities — Damascus, Homs, Aleppo, Latakia, Palmyra, Daraa, Deir ez-Zor and Idlib for the period of 2010 (before the military conflict) and 2023 were performed, which showed a decrease in the sustainability index up to two times. This is due to the destruction of residential areas of engineering and transport systems, destruction of cultural heritage objects. It is also found that tangible cultural heritage has a great impact on the sustainability of the city system.Conclusions. The proposed model for determining the index of urban sustainability (IS) allows us to obtain a quantitative assessment and analyze the impact of each factor. It is shown that along with the restoration of residential areas and objects of engineering and transport infrastructure, it is necessary to carry out works to preserve objects of cultural heritage, the loss of which leads to a decrease in the sustainability of the city, the loss of its urban identity.

Introduction. The impact of street art on the state of space of the modern city is investigated. The object of the research is the modern urban environment considered in the context of the changing perception of street art by the urban population. The aspects of forming a favourable urban environment from the point of view of urban dweller’s stay in it are considered.Materials and methods. The methodological basis of the research is an analytical review of materials reflecting the interaction between art and the viewer in general, and street subculture and the urban dweller in particular. The focus of this paper is the concept of the functionality of the time-changing urban environment and its human perception. The research methodology is based on the analysis of the urban space of Ryazan through the prism of its perception by the urban population. The empirical base contains materials, including a statistical study of the opinion of the target audience of teachers, staff and students of the Ryazan Institute (branch) of the Moscow Polytechnic University regarding the existence of the social phenomenon of street art, its dynamics and impact on public opinion, an interview reflecting the view of the artist Alexander Sinitsyn on the state of the Street art movement in Ryazan and the authors’ own participation as artists in the social project “The City in Colours”, which took place in the summer of 2022. The concrete fence of the railway tracks in Moskovskaya street was the object of creativity.Results. The main factors influencing the perception of street art by the population are revealed, the data of statistical research of the state of public consciousness is carried out, reflecting aesthetic views, social activity, involvement in the processes of transformation of the urban environment, the dynamics of perception of the visual range contained in street art objects. The authors of the paper determined the average level of awareness of residents about the activities of street artists and various works of street art.Conclusions. Street art is a new direction that is undergoing transformation processes, adapting to new trends in the modern structure of society and people’s consciousness. Modern subculture of street art will be in demand on the territory of urban space, thanks to its informational, propaganda and aesthetic component.

Introduction. The method of reliability coefficients with fixed values (declared in regulatory documents) is used as a basic method of limit state verification. However, there is a more general formulation of the semi-probabilistic method, within which the specificity of the design (e.g. information on the variability of actual dimensions, material properties, etc.) and the specificity of the location (e.g. information about climatic loads) can be taken into account more accurately. This method is referred to as the modified (adjustable) partial factor method.Materials and methods. The paper is aimed at the development of the method of reliability coefficients with adjustable values for the design of steel structures and the scientific justification of the parameters of this method. The methodological formulation of this method is based on determining the design values of the basic variables based on the distribution function for a given quantile. In this case, the quantile of the distribution is calculated using the sensitivity coefficients of the basic variables of the first-order reliability method and the target value of the reliability index.Results. The study describes in a general formulation a method of reliability coefficients with adjustable values for the design of steel structures, which allows explicitly taking into account the target reliability level and variability of the basic variables. In the course of the study, the scientific substantiation of the sensitivity coefficients of the basic variables based on the first-order reliability method was performed and instructions on the purpose of probabilistic models of random variables were presented.Conclusions. The analysis of the generalized function of the limiting state of the steel element by the probabilistic method showed that the sensitivity coefficients change significantly with the change in the loading parameter (characterizing the ratio of variable loads to the total), while it changes slightly depending on the type of variable load itself. Sensitivity coefficients can be assumed based on graphs or simplified dependencies presented in this study. Conservatively, the sensitivity coefficient values for the bearing capacity of the steel element can be assumed to be 0.6, for constant loading –0.4 and for variable loading –0.9.

Introduction. The current state of investment and construction activities at the corporate level is determined not only by the complexity of applied engineering solutions of capital construction facilities, but also by changes in a similar trend of external and internal environments of economic entities involved in the construction of a building or structure. Such complication is caused by the permanent increase of scientific and technological progress and the manifestation of economic phenomena corresponding to it, which affect the demands of consumers and regulatory rules of the state. As a result, there is an increase in contradictions between the conditions for the implementation of investment and construction activities and the organization of construction management, which is the reason for the emergence of new options for the implementation of business processes, their addition and integration with production and security processes, i.e. the emergence of new organizational schemes for construction management. One of these schemes can be used to manage construction on the basis of production and engineering centre. As noted in the paper, the main direction of increasing efficiency in this organizational structure is the transformation of management processes, i.e. their reengineering.Materials and methods. The research is based on the postulates of cybernetics, the logistics of regulatory influences, the organization of production systems, and structural and functional analysis. The scientific background of the authors was used, which was reflected in their publications on this problem. Additional sources were scientific works of domestic and foreign scientists in this subject area.Results. The structure and composition of the production and engineering centre are substantiated, the distribution of the main groups of functions is performed, the place of such an organizational structure in the corporate management system of investment and construction activities is determined, and the directions of business process reengineering are established.Conclusions. The formation of new, modern organizational structures is a promising direction of business process reengineering to increase the efficiency of construction, improve the quality of construction products, as well as the interaction of participants of investment and construction activities.

Introduction. When justifying design decisions in hydraulic engineering, developing measures for the use and protection of water resources, information on the intra-annual distribution of runoff is of practical and scientific interest. The paper presents the results of a correlation analysis of daily water levels in the rivers of the Kaliningrad region, based on the results of observations in years with different water content from 2008 to 2021.Materials and methods. The statistical analysis of the data set of observations of daily water levels in 12 river stations of the Kaliningrad region for the period from 2008 to 2021 was carried out. The data source was the automated information system of state monitoring of water bodies. The observation results were processed in Mathcad environment.Results. Pair correlation coefficients between daily water levels in the studied river stations of the Kaliningrad region were calculated. The average, maximum and minimum pair correlation coefficients of daily water levels in the considered stations were determined. The dependence of pair correlation coefficients of daily water levels in two stations located in the same river system (The Angrapa River – Berestovo gauging station – The Pregolya River – Gvardeysk gauging station) and for different river systems (The Mamonovka River – Mamonovo gauging station – The Pregolya River – Chernyakhovsk gauging station) was determined.Conclusions. It was found that the closest stochastic relationship of daily water levels is observed near the Neman and Matrosovka Rivers; in dry years, the values of the pair correlation coefficients of daily water levels decrease in the studied stations; The Pregolya river (Gvardeysk gauging station) and the Instruch River (Ulyanovo gauging station) should be recommended as analogues for watercourses of the Kaliningrad region. The obtained results can be used for the development of measures for the use and protection of water resources in the region.

Introduction. When designing metal structures, many factors are taken into account, including the suppleness of joints, which affects the results of stress-strain calculations of structural elements. In the design of high-rise buildings, outriggers are provided to distribute wind loads between the core and perimeter columns, reducing horizontal displacements. Considering the suppleness in the joints of the outrigger affects the distribution of forces in the building structure elements, as well as on the building deformations. This paper presents an analysis of the influence of considering the suppleness of outrigger joints on the stress-strain state of structural elements of a steel high-rise building.Materials and methods. The research focuses on a structural model of a 60-story building with an outrigger, modelled using the ETABS software. The suppleness of the joints of the outrigger structures was determined using the IDEA StatiCa software.Results. According to the results of static calculations considering the suppleness of the outrigger joints, when placing one outrigger on the 54th floor, the maximum horizontal displacement at the top of the building increased by 2.9 % compared to calculations without considering suppleness. Placing two outriggers increased it by 4.7 %. The maximum axial force value in the outrigger brace decreased by 23 % compared to calculations without considering suppleness, while the maximum bending moment increased by 10 %.Conclusions. When calculating a high-rise building taking into account suppleness, the values of horizontal displacement at the building’s top increase within 5 %. If it is necessary to limit horizontal displacements, calculations should consider the suppleness of the joints in steel outrigger structures. Additionally, considering suppleness in calculations allows reducing the material intensity of the designed outrigger braces, as the determining force is the axial force, which decreases by about 25 % when calculated considering suppleness.

Introduction. Quantitative assessment of the structural reliability and safety level for structural solutions is an actual scientific and technical problem. The measure of reliability in this case can be the failure probability of a structural element. In practical problems of assessment and analysis of structural reliability, data on random variables can be obtained in the interval form (qualitative uncertainty), while the classic methods of reliability analysis do not allow to estimate reliability in the presence of such data. Lack of statistical data (quantitative uncertainty) is also present in practical tasks of reliability analysis.Materials and methods. The paper considers the use of the theory of evidence as an effective tool for reliability analysis of steel span structures in problems with interval uncertainty of statistical data.Results. The graphical interpretation of the reliability analysis algorithm is given. It allows to obtain clearly and operatively an estimate of the failure probability of the structural element, as well as to reduce the permissible load on the element to the required reliability level. Two-dimensional and three-dimensional models are considered for analyzing the reliability of a steel truss bar according to the buckling criterion.Conclusions. The theory of evidence allows effective modelling of various sources of uncertainties in practical engineering problems. Thus, with limited data, it is possible to get an idea of the quantitative expression of the reliability level by its lower bound, which can be increased by strengthening the element, more detailed probabilistic analysis or limiting the operational load on the structural element. By considering more non-deterministic quantities in the design, the engineer obtains a more cautious decision. When considering the cross-sectional area as a random variable, the reliability of the truss bar on the buckling was 23 % lower (lower reliability bound) than in a similar calculation with a deterministic value.

Introduction. The paper describes experimental and theoretical work on the study of the characteristics of a layered building material — thermal timber, consisting of solid wood and layers of thermal insulation. Such materials are used for construction of lightly built wooden houses of private sector and low-rise houses. The peculiarities of this type of materials is that simultaneously with the construction material — wood beam contains a layer or layers of insulation, which allows to reduce the stage of insulation of the house during its construction. Strong wood and absolutely nothing capable of carrying insulation together can give a material whose characteristics are fundamentally different from both the first and the second.Materials and methods. The influence of the number and thickness of layers of thermal insulation and wood on the strength and thermal insulation characteristics of the resulting timber is considered. Knowing the regularities of changing characteristics from the number of layers, it becomes possible to choose a rational system of alternation of wood and insulation layers. Experimental studies of beams with different number and thickness of thermal insulation and power layers were carried out, the total thickness of both power and thermal insulation layers in each beam were the same, but the sequence of laying was changed.Results. The results of the experimental study of the bending strength of the thermal timber and the calculated study of its thermal insulation characteristics are shown. Dependences of maximum loads for beams with different number of wood/insulation layers were experimentally obtained.Conclusions. As a result of the experiments it turned out that the linear bending theory cannot accurately describe the behaviour of the layered material — the withstand load grew with the increase in the number of layers.

Introduction. Restrictions imposed by Western countries on the access of the Russian financial system to international clearing systems significantly complicate the development of economic sectors that are deeply integrated into international supply chains. Among them, it is necessary to single out the construction industry, which acts as a “locomotive” for the development of many other types of economic activity. This paper is devoted to the review of emerging macroeconomic effects in the context of leveling the risks of the growth dynamics of the construction industry of the Russian Federation within the framework of the transition of the national payment system to blockchain (DLT) in the context of solving the issue of import substitution. The subject of the study is the features of the prospects for sustainable development of the Russian economy in the context of adjusting the import of construction materials.Materials and methods. The tools of building a system of recursive equations estimating macroeconomic externalities in the process of simulation modelling of blockchain use in the system of ensuring sustainable settlements with foreign counterparties, as well as correlation and regression analysis, which forms the basis for identifying the impact of the Russian construction industry on the prospects for GDP growth were applied.Results. The short-term potential of possible slowdown of Russia’s GDP growth (–0.45 % per year) as part of the localization of import supplies of building materials. It is substantiated that the risks of limiting the supply of building materials can be ensured through the introduction of blockchain technologies into the system of cross-border payments of the Russian Federation, which form a new basis for the movement of cash flows.Conclusions. The value of the obtained research results consists in the identified and empirically substantiated risks of slowing down the development of the construction industry and the national economy of the Russian Federation as a whole within the framework of possible localization of supplies of building materials from abroad as a result of sanctions pressure on financial markets. It is substantiated that the creation of regional blockchain platforms on a global scale can act as a tool for leveling risks, providing the possibility of stability and independence of the formation of transnational supply chains from global clearing services.

Introduction. The paper substantiates the relevance of creating and improving digital tools for complex scientific research and development work based on the information model of a construction object at all stages of the life cycle. The research focuses on environmentally safe (green) construction in the northern and Arctic regions. The purpose of the study is to substantiate a set of criteria for “green” for the northern and Arctic regions of the Russian Federation on the basis of logically interrelated models: a design model, a full-scale model, mathematical models and a digital twin model. The main criteria include energy efficiency and environmental safety of buildings.Materials and methods. The objects of the study are two twin buildings designed and built according to the programme of scientific research in the Republic of Karelia and the Murmansk region. The objects are identical, but the conditions of their functioning are different. The methodology of complex scientific research for each stage of the life cycle of objects is proposed. The methods of comparative analysis and the method of expert assessments were used, as well as the methods presented in the normative and technical documents of the technical regulation system of the Russian Federation related to the technological aspects of construction.Results. Four groups of basic construction criteria for the northern and Arctic regions of the Russian Federation are defined: external environment; internal environment; materials and technologies; energy efficiency. The Research Information Model (RIM) was developed as a tool for comprehensive scientific research in the field of construction technologies in the northern and Arctic regions. The practical implementation of the results of the study at the two above-mentioned facilities, including digital monitoring of the condition of the facilities for two years (2021–2023), is considered. Prospects for the continuation of the research are determined.Conclusions. The necessity of the development is justified and the expediency of using the developed information model of research is confirmed by the example of two constructed objects. The experience of using the main blocks of the model and digital monitoring of the condition of objects for two years has confirmed the expediency of using information modelling and continuing research to improve construction technologies in the northern and Arctic regions.

Introduction. The study was carried out to determine the possible causes of damage to the finishing plaster coverings on the facades of historical stone buildings, built in St. Petersburg before 1917, as a result of their humidification and subsequent frost destruction.Materials and methods. The mechanism of humidification of a homogeneous wall structure plastered on both sides due to the moisture transfer from the room to the environment through the wall thickness due to the difference in partial pressures of water vapour from inside and outside the room during the cold season is studied. The paper provides the graphs of the distribution of the actual and maximum partial pressures of water vapour over the thickness of the wall structure, depending on the type of plaster covering, for two calculated cases — for the conditions of the coldest month and the coldest five-day period in St. Petersburg.Results. It is revealed that for the conditions of the coldest month in St. Petersburg, the actual partial pressure of water vapour in the thickness of the wall structure under consideration does not exceed the maximum, which indicates the absence of conditions for moisture condensation in the thickness of the wall envelope. However, as the vapour permeability of the external plaster decreases, the curves of the distribution of the actual and maximum partial pressures converge at the interface of the stone base and the plaster covering. For the conditions of the coldest five-day period, the actual partial pressure of water vapour already at a distance of 135 mm from the inner surface exceeds the maximum partial pressure, which indicates a high risk of moisture condensation, and this risk is the higher the less vapour permeable the plaster covering is.Conclusions. It is proven that when the coldest outdoor temperatures are established, there is a high probability of condensation of water vapour in the thickness of the wall structure under consideration. The highest risk of freezing of the condensable moisture will be observed at the interface of stone base with the external plaster. Freezing of moisture in cracks and voids in the contact zone of the stone base and the plaster covering can lead to water trapping, the occurrence of significant internal stresses in the finishing layer and, as a result, to its gradual damage, up to the loss of individual fragments of plaster.

Introduction. The problem of preservation of decorative elements on the roofs of multi-apartment residential buildings is considered. The authors note the historical and architectural value of such structures in creating the appearance of the city. An analysis of the current technical condition of decorative elements of roofs is carried out using the example of individual apartment buildings in Samara and, based on a comprehensive analysis, recommendations are given for their further operation. The problematics is investigated by the authors using the example of Samara city and, accordingly, are based on the practical basis of this city. At the same time, the questions and proposals posed in the paper are relevant and can be extended to the residential development of most Russian cities. This is due to the fact that the organizational and legal field of this problem is established at the level of federal legislation, and in the regions it develops only in the form of not the most significant features.Materials and methods. When developing the present problem, the authors used a set of generally accepted research methods — observation, comparison, measurement, abstraction — in adaptation to the object and subject of research. The research is based on the materials and results of the author’s own research in relation to technical, cost and regulatory parameters of the repair of decorative elements of flat roofs of multi-apartment high-rise buildings, made according to a standard and individual project in Samara city.Results. The regulatory and legal framework in force in relation to the overhaul of the common property of an apartment building is analyzed. Defects and problems were identified — corrosion of metal structures, destruction of wooden elements. The impact of dismantling of structures on the appearance of buildings is assessed. A comparative assessment of the cost of repair and restoration of roof elements is given. The current regulatory framework for overhaul in apartment buildings is analyzed. It is noted that there is no clear regulation of financing the repair of the roof structures under consideration. The estimated cost of overhaul of additional roof elements is determined according to alternative options for its production. The conclusion is made about the need for an integrated approach, taking into account the technical condition, financial capabilities and legal regulation to solve the identified problem.Conclusions. Proposals are made to improve the normative-methodical and normative-technical mechanisms to ensure the safety of historically and architecturally valuable elements of roofs and the safe operation of apartment buildings in Samara.

Introduction. The Republic of Belarus is one of the first countries on the territory of the CIS, which introduced European design standards (Eurocodes) on its territory, while preserving the effect of building standards developed on the basis of Soviet SNIP. The republic accumulated considerable experience in the practical application and comparative analysis of these two systems of standards. The relevance of this study is contained in the discovery of the most distinctive features of normative documents, on the basis of which it is possible to determine further directions of scientific research and improvement of domestic norms.Materials and methods. Analysis and generalization of experience.Results. The paper presents the results of generalization of the experience of practical application and comparative analysis of Eurocode and CP in relation to the design of steel structures. The analysis of partial factors, classification of cross sections, welded and bolted joints is given.Conclusions. Methodological approaches to checking limit states and ensuring the reliability of steel structures in CP and Eurocodes are very similar, but there are differences in the values and sets of partial factors. When designing steel structures according to Eurocode, the methods of classification of cross-sections of rolled profiles produced according to GOST or TS need to be adjusted. Eurocode 3 provides more possibilities in the design of welded and bolted joints.

Introduction. When choosing the Engineering, Procurement, Construction (EPC) contract model, the life cycle of construction projects is managed by a specialized contractor organization. This form of construction project management is relatively new for Russian developers, and its successful implementation depends on various organizational and technical solutions, in particular, logistics management. The research problem is related to the existing risks of organizing the supply of material and technical resources during the implementation of construction projects using the EPC model, which have a negative impact on the most important indicators of construction efficiency, such as timing and cost. The paper describes strategies for preventing risk events that occur when planning the supply of material and technical resources during the life cycle of construction projects (risks of price changes, risks of violation of contractual obligations, risks of changes in the quality of delivery, reputational risks and risks of significant changes in demand). The problems of risk mitigation using lean manufacturing tools were solved.Materials and methods. The methodology and standards of project management as applied to the processes of material and technical support of construction, as well as methods of calendar-network planning, methods of project content decomposition, methods of contract strategy of construction projects implementation and elements of the methodology of package-node method of construction were used.Results. The results of the research are described and recommendations are given for the practical use of the flexible project management tool known in international practice as Just In Time.Conclusions. A justification for the use of the proposed planning tool as an activity to reduce risks associated with the supply of materials and improve the efficiency of life cycle management of construction projects is presented.

Introduction. The available methods of assessment of bearing capacity by deformations of foundations mainly take into account single static loads of short duration or cyclic loads with unchanged values during the whole period of operation. The effect of cyclic loading of non-stationary regimes on the behavior of soil bases is practically not studied. In this connection, the research was carried out to develop a method for calculating the settlement of the bearing capacity of clay foundations under block cyclic loading.Materials and methods. To achieve the purpose of this paper, experimental studies of clay foundations in triaxial compression and tray test devices, as well as theoretical studies to determine the bearing capacity and settlement of clay foundations under different loading regimes were carried out.Results. On the basis of existing calculations of bearing capacity and settlement of foundations and the study of the behavior of clay soils under cyclic loads, the equations in compact form are obtained, which make it possible to take into account the peculiarities of deformation of clay soils significantly reducing the complexity and accuracy of the calculations. The development of methods for calculating the bearing capacity and settlement of clay foundations under block cyclic loads is at a sufficiently high level.Conclusions. A method for calculating the bearing capacity of clay foundations under block cyclic loading is proposed and an engineering method for calculating the settlement of clay foundations is developed, based on the method of layer-by-layer summation, which takes into account the simultaneous change in the spatial stress-strain state and mechanical characteristics of soils in the process of mode block cyclic loading.

Introduction. One of the main tasks of the theory of oscillations of building structures is the determination of the fundamental frequency of natural oscillations. Analytical solutions are rare here and, as a rule, are based on approximate estimates of the first frequency from above (Rayleigh’s method) or from below (Dunkerley’s estimate). Most often, the problem of natural oscillations is solved numerically by the finite element method using specialized packages. In this paper, the task is to derive analytical estimates of the dependence of the first oscillation frequency of a lattice truss on the number of panels, the geometric characteristics of the structure, and the parameters of the elastic properties of the material.Materials and methods. A flat statically determinable lattice is supported by its base on struts. The angular support is a fixed joint. Calculation of forces in structural elements is performed by cutting out nodes using standard operators of the Maple symbolic mathematics system. The rigidity of the truss is found by the Maxwell – Mohr formula. The mass of the truss is distributed uniformly over its nodes. Mass oscillations occur vertically. By generalizing a series of solutions for trusses with a successively increasing order to an arbitrary number of panels, the desired formulas are derived by induction.Results. A case of kinematic variability of the proposed truss scheme was noticed. Formulas for the first frequency are obtained by the Dunkerley and Rayleigh method. The two analytical solutions are compared with the numerical solution obtained for the entire frequency spectrum. Spectral constants and resonant safety regions were discovered in the spectra of a family of regular trusses.Conclusions. The two-sided method for estimating the first frequency is applicable to solving problems on regular constructions, where the final formula includes the order of regularity as a parameter. For the construction under consideration, the error of the Rayleigh method is comparable to the error of the Dunkerley method.

Introduction. Large-scale field studies of the destruction of brickwork carried out by the author in many regions of the world showed that the approach to the research of the durability of building ceramics based on the strength parameter and the frost resistance parameter are not indicative. These parameters do not make it possible to obtain a temporary value of the durability of the material, but are just the basis for an expert assessment.Materials and methods. This paper proves the scientific hypothesis put forward by the author that the destruction of brick material in the brickwork of enclosing structures occurs under the influence of chemical corrosion processes. The process of chemical corrosion is described, the results of thermodynamic calculations of chemical processes are briefly presented. A brief description of the methods of studying the durability of the building ceramics material, which have now received the status of standards, is given.Results. The results of laboratory studies of the process of chemical destruction of the building ceramics material, as well as calculations of the durability of the building ceramics material performed on the basis of the developed method of calculating the durability of the material are presented.Conclusions. Based on the developed theoretical justification and laboratory studies of the process of chemical destruction of the wall ceramics material, it is concluded that the created research methodology and calculation method allow to determine the durability of the material at any stage of its operation.

Introduction. Dynamic development of retail trade in construction materials increases the requirements for timely delivery of goods to store warehouses. Well-established classical algorithms are focused on calculating the target inventory by taking into account the sales history, which characterizes real demand, because it is subject to distortions caused by the influence of marketing campaigns, stock shortages and abnormal sales. Under such conditions, it is incorrect to predict inventories using the classical algorithm. The evolution of forecasting methods is characterized by a shift in emphasis from demand for goods to inventory management. For this reason, it is necessary to develop the practice of modelling orders to suppliers of construction materials. In turn, there is a problem of forecasting the supply of stocks of construction materials. The purpose of the paper is to assess the capabilities of existing methods of forecasting stocks of construction materials of a particular group during deliveries. Research objectives: to analyze the possibilities of existing forecasting methods for the task of inventory management; to carry out the necessary statistical calculations for forecasting inventories.Materials and methods. Methods of theoretical analysis of scientific literature, statistical data analysis and comparative analysis, method of calculating the root mean square error of modelling RMSE, Holt method and simulation modelling were used for the research tasks.Results. Based on the root mean square error of the RMSE modeling, the size of the error is established for each of the analyzed inventory forecasting methods.Conclusions. Based on the calculations, it is determined that the most optimal method for forecasting inventories of construction materials is the method of simulation modelling, since it allows forecasting with the smallest degree of error.

Introduction. The authors of the paper studied the issue of competition in the modern Russian market of the residential real estate. A little-studied aspect — the choice of the lexical means and forms contributing to better sales — is studied.Materials and methods. Works of domestic and foreign authors, as well as the content from official websites, prospects, outdoor advertizing and information from some of the largest developers operating in Moscow and Moscow region were considered as the materials of the research. The authors used such methods as observation, description, poll, quantitative statistical analysis, comparative analysis, structural analysis, semantic-stylistic analysis, frequency analysis, etc.Results. The authors studied the influence of language image on pricing and popularity among buyers in the market of the residential real estate. The analysis of offers of the largest developers operating in Moscow and Moscow region confirmed the assumption that the best sales, as well as the formation of higher prices, are promoted by the use of foreign words in the names of housing estates, foreign loan words to denote rooms and spaces (“lounge zone”, “play-hub”, co-working), epithets like “club house”, etc.Conclusions. As the result of the conducted research, the authors made the conclusion, that language images in names, in the description and advertizing of housing estates are an effective instrument to increase their competitiveness, better market promotion and profitable sales at higher prices. The idea that there is also a downside to this phenomenon and it is put forward as a debatable point: the language image, which forms an image of the housing estate as elite, closed, accessible only to a narrow circle of residents, and at the same time self-sufficient, providing them not only with housing, but also with a wide range of social and domestic services and even business space, leads to isolation and some kind of enclave in such complexes. Nowadays there is an a desocialization of the residents of housing estates, spreading a lifestyle that does not involve unnecessary contacts in the “outside world”, and in fact, that means the formation of a new paradigm in housing construction and a new urban philosophy.

Introduction. In the current climate change conditions, the protection of irrigation structures, especially dams, is a very important task. Seepage is one of the main causes of dam failure, so it is very important to investigate the seepage regimes and find solutions to prevent dam failures as a result of the seepage processes in earth dams. In this paper, the analysis of the seepage regimes in the body of earth dams is performed by means of mathematical modelling using numerical finite element models. A homogeneous earth dam with an imperfect diaphragm on an impermeable foundation is taken as the object of study. The purpose of the study is to determine the influence of relative parameters: diaphragm height, diaphragm location in the dam body, their number. In addition, the influence of diaphragm parameters on the seepage flow through the dam body and its velocity is analyzed.Materials and methods. The study was carried out with the help of numerical modelling using PLAXIS 2D software. The model of the dam is based on typical design solutions used in practice.Results. The results of the study show that the placement of the diaphragm in the dam body reduces the seepage flow through the dam and the height of the diaphragm is inversely proportional to the seepage rate. The maximum seepage rate was recorded at the upper end of the diaphragm and its magnitude is directly proportional to the height of the diaphragm. When the diaphragm is displaced towards the downstream side, the filtration rate slightly decreases. The value of maximum velocity increases when the diaphragm is displaced towards the downstream end.Conclusions. Dam failure due to seepage can result in serious property damage and loss of life. Implementing methods that reduce seepage discharge and seepage velocities is important to ensure safe dam operating conditions

Introduction. The formation of an effective organizational structure of construction production management at the corporate level implies adaptation to new conditions. However, in this process, there is a problem of a gap (differentiation) of the plan and action, which requires corrective actions, including with regard to the organizational structure and management processes (business processes) of investment and construction activities. In the future, such impacts will determine the nature of reengineering activities in this area. Business process reengineering and organizational structure reengineering are considered. There is a certain dependence between these types of qualitative organizational transformations, which is primarily due to the transience of the modern life cycle of engineering solutions. Thus, it is possible to identify the purpose of the research — it is a scientific justification for the improvement of the corporate regulation system through reengineering of the organizational structure and business processes of investment and construction activities. On this basis, it is possible to formulate the objectives of the research: to establish the regularity of the gap (differentiation) of the plan and action in the system of corporate governance, to identify the dependence of business processes and organizational structure of investment and construction activities in the context of reengineering of business processes and organizational structure in construction. The object of the research is the system of corporate regulation of investment and construction activities, and the subject is the organizational structure and business processes in construction. From the point of view of practical value, these types of reengineering allow an economic entity to improve the quality and efficiency of construction products by focusing production activities on the consumer and a process approach in management. On this basis it will help to gain competitive advantages, among other things through the wider use of technical means, employees meeting higher requirements of scientific and technical progress and capable of solving complex problems of investment and construction activities, arising at the present stage, in the shortest possible time.Materials and methods. The theoretical basis of the research was a system approach, logistics of regulatory impacts, structural and functional analysis, methods of investment design, strategic and operational management. The information base of the research was the scientific search carried out by the authors earlier, which was reflected in published papers on this subject. Additional sources were scientific works of domestic and foreign scientists, as well as practical materials.Results. The solution of the gap (differentiation) problem in investment and construction activities is shown, which made it possible to propose a scheme of regulation of a construction company, to establish dependencies of business processes and organizational structure of investment and construction activities, as well as dependencies of business process reengineering and organizational structure reengineering in construction.Conclusions. The gap (differentiation) between the plan and the action of a construction organization is caused by fluctuations in the external environment. The main tool for effective adaptation to external fluctuations and corporate regulation is a qualitative transformation of business processes and organizational structure, i.e. their reengineering.

Introduction. The paper illustrates the necessity and place of the problem of stability assessment of lifting devices applied for excavation in cramped conditions, which are typical for urban areas with dense urban development when laying underground transport facilities on the example of the open method of works on the construction of the Moscow Metro.Materials and methods. Two sites on the territory of Moscow and different cranes of Liebherr company were considered in order to investigate the influence of geotechnical parameters on stability and safety of heavy lifting equipment. In addition, numerical modelling was carried out to determine displacements and deformations at different locations of the crane with respect to the excavation fence.Results. Horizontal and vertical displacements and total deformations of the pit fence were obtained by means of numerical modelling with the use of geotechnical software systems PLAXIS 2D and PLAXIS 3D. Among other things, we analyzed the usage of PAG slabs, as well as construction of the top tier of the spacing system with the use of 1.5 × 1.5 m inventory slabs.Conclusions. The relevant issue is an analytical calculation for situations that can arise in solving practical problems, in particular, in the development of the project of works for the installation of a lifting device near the pit with a fence. Surface layers of soils (up to 6 m) have a special and primary influence on the result of the calculation. If the lifting device is installed in bulk soil of natural origin, it is mandatory to replace it with a harder soil or to lay additional concrete slabs with a larger area to reduce the direct load on the ground. In special cases, the numerical modelling should be performed separately for heavy truck cranes with a lifting capacity of 250 tons and more, provided that the guardrail is made without a spacing system (“cantilever type”).

Introduction. Reinforced concrete structures of buildings have significant fire resistance, but high-temperature effects lead to changes in strength and deformation characteristics of concrete and reinforcement of structures. In addition, for prestressed reinforced concrete structures, fire impacts can be associated with partial or even complete loss of prestress. At the same time, it is the prestress of the reinforcement that makes it possible to limit the width of the crack opening and the deflection of reinforced concrete structures within acceptable limits.Materials and methods. The paper presents and analyzes the results of analytical calculations of the bearing capacity and serviceability of a prestressed reinforced concrete ribbed floor slab before and after high-temperature fire impact on it. After fire exposure, the calculations are carried out with a complete loss of pre-stressing by the reinforcement. The heating temperature of the concrete in the compressed zone and tension reinforcement in the calculated cross section of the floor slab is taken according to the results of experimental studies.Results. The comparison of the floor slab deflections obtained by calculation and experimentally indicates the presence of additional factors (temperature expansion of concrete and reinforcement, high-temperature creep of reinforcement) that determine the increased value of the experimental floor slab deflection compared to the calculated one. The structural solution of the floor slab is analyzed, the feasibility of increasing the area of longitudinal tensile reinforcement to increase the bearing capacity and reduce the crack opening width in the slab is considered. The effect of fire protection on the heating temperature of the concrete in the compressed zone and the tensile reinforcement of the slab is shown.Conclusions. An analysis of the results of calculating a prestressed concrete ribbed floor slab before and after a fire showed a slight decrease in its bearing capacity after fire impact, an increase in the width of the crack opening and a significant increase in the deflection of the slab.

Introduction. The relevance of using modern methods for continuous assessment of the actual condition of road and railway bridges, industrial and other engineering structures is substantiated. The results of wide application of optical method for continuous control of technical condition of engineering structures under real operating conditions are presented.Materials and methods. Using quasi-distributed fibre-optic sensors based on fibre Bragg gratings. This paper presents experience in the application of fibre-optic monitoring systems, which generally include — a set of fibre-optic sensors (FOS), built on different physical principles, — multi-channel devices for their interrogation (interrogators), — built-in special software (Open source software) designed for collecting, processing and visualizing monitoring data. Among the most well-known developers and suppliers of composite systems for external reinforcement based on carbon reinforcing fibres, it is worth mentioning foreign and domestic materials under the trademarks of MasterBrace (BASF SE, Germany), SikaWrap (Sika Group, Germany), Torayca (Toray Industries, Japan), FibARM ( JSC “Prepreg-SСM”, Russia), S&P (JSC “Triada-Holding”, Russia) and others. Some of the first regulatory documents establishing requirements for organizing monitoring in the construction industry are MGSN 4.19–2005, GOST R 22.1.12–2005, MRDS-02–08 and some others.Results. It was established that one of the most promising technologies for restoration of damaged structures is the application of external reinforcement systems made of polymer composite materials based on carbon fibres and cold-curing polymer binders. The experience of practical application of composite systems of external reinforcement of engineering structures is described.Conclusions. It is shown that the results of such control allow timely revealing the reduction of bearing capacity, occurrence of operational damages, planning repair measures that the application of fibre-optic methods and means of continuous diagnostics and composite systems of external reinforcement in a complex, allows to provide safety of operation of engineering constructions in real conditions.