Methods for calculating technological and functional tolerances in the manufacture and installation of steel structures are described. An experimental installation of the structure was carried out to make it possible to clarify the tolerances, and the foundations of the methodology for assessing the qualitative and quantitative manufacturability of assembly elements were put forward to simplify the processes of manufacturing and assembling the structure.

Keywords: methods for calculating tolerances, installation of a structure, manufacturing of structures, manufacturability, complex indicator of manufacturability

The stages of pre-project and design preparation are fundamental for the further implementation of the investment and construction project. The success of construction and commissioning of facilities depends on the successful completion of these stages. The duration of the stages depends on the competence and consistency of interaction between the participants in the investment and construction project, the rationality of decision-making by the technical customer (developer) and a number of other factors. Identifying factors and finding options for rational planning of the stages of pre-project and design preparation is very relevant. As part of the study, a formula was derived for determining the duration of the stages of pre-design and design preparation of objects for construction, taking into account the influence of negative factors. The results of the study are used in planning the stages of pre-design and design preparation of a facility for construction.

Keywords: factors, stages of pre-project and design preparation of objects for construction, duration of procedures

The article provides an overview of the characteristic defects that occur during winter concreting as a result of violations of the technology of concrete work. The relevance of this topic is justified by the large-scale increase in the volume of construction of monolithic buildings for various purposes: residential, public, as well as various types of structures made of monolithic reinforced concrete. A feature of the review of these defects is in this case their main causes, which are associated with violations of concreting technology due to the need in some cases to accelerate production work. The defects presented in this article were identified based on the analysis of accounting documentation when performing visual surveys in the process of scientific and technical support for the construction of buildings of increased responsibility. The violations described in the article were observed at various monolithic construction sites within modern megacities. The article describes the main causes of these defects. The ways of eliminating these defects based on engineering practice are proposed.

Keywords: inspection of building structures, defects of monolithic structures, scientific and technical support of construction, flaw detection of building structures, concreting in winter

This article is devoted to the analysis of the application of the software and hardware complex of mixed reality and augmented reality ""BRIO MRS"" to explore the possibility of digitalization of the construction control process within the framework of JSC CITY - XXI Century. The article also discusses the specific application of mixed reality, which consists in checking the progress of work on the construction of a real building and its compliance with the designed digital information model using a hardware and software complex for augmented and mixed reality. The complex described in this article was actually used and is being used at the construction site. The paper describes the procedure for using a hardware and software complex to verify the compliance of the progress of construction work and the digital information model. The principle of operation of the complex, as well as the prospects that were discovered during the implementation of the experience of using a mixed and augmented reality system, are the subject of further research. In conclusion, based on the conducted research, it turns out what tasks the complex described in the article allows to solve, what advantages it has over analogues and what advantages its introduction into the activities of a modern development company will bring.

Keywords: mixed reality, augmented reality, digitalization, digital information model, modern standards, hardware and software complex, construction control

The study highlights issues related to the characteristics of industrial facilities, and provides existing methods for evaluating facilities. The use of the concept of a complex indicator combining a number of indicators of an industrial facility in the design is proposed. It is assumed that the availability of systematized information about an industrial facility at the design stage will allow a more rational approach to the issue of forming a project team that is sufficient and effective for the implementation of the project.

Keywords: construction, industrial construction, industrial facility, design, integrated indicator, project team, organizational structure

The focus is on the building construction technologies using 3D modular building blocks, which are capable of changing their geometric dimensions and shape or remaining unchanged during installation. The paper discusses the main advantages of using 3D modular building blocks for building construction and offers specific examples showing the related process flows. It also shows horizontal and vertical nodal joints and provides a comparison of two options based on certain criteria of installation adaptability.

Keywords: buildings, construction technology, installation and transport manufacturability, horizontal and vertical connections, technological processes

In the course of the study, an analysis of the condition of the mosaic floor covering in various operating conditions and at various facilities was carried out. The main advantages and disadvantages of floor coverings using marble, the features of their operation are revealed. The purpose of the study is to simplify and confirm the acceptability of the technology of marble floors, taking into account the factors of influence and the type of room. The main tasks are to conduct a study on the wear of the floor covering over time; to determine the timing of the current repair of the floor covering; to conduct a study of the preservation of the reflectivity (gloss) of floor coverings using marble. The practical significance lies in drawing up a graph of the dependence of floor wear on its type and time based on the analysis of visual inspection and physical measurements.

Keywords: marble floor, polishing, grinding, wear, breccia, mosaic coating, technology, profiler, restoration, seamless, colored concretes

This article provides a comprehensive overview of the primary technologies used in the construction of high-rise buildings in China. It delves into the most commonly employed construction techniques and the types of structures that are prevalent in this sector. The study is based on a thorough analysis of existing literature and showcases real-world examples to illustrate the application of these technologies. These techniques encompass various construction methods and material choices, which are critical in the successful erection of skyscrapers. The aim of this paper is to offer reference information for professionals, aiding them in selecting suitable technologies and structural types for high-rise building projects. This work is especially useful for those in the construction industry, as it highlights the significant role that building technologies play in high-rise construction. It serves as a practical guide, providing insights into the most widely used construction technologies in the field. This article is intended to be a valuable resource for specialists looking to employ advanced methods in their construction practices, thereby enhancing the efficiency and sustainability of high-rise buildings.

Keywords: civil engineering, high-rise buildings, construction technology, reinforced concrete structure, prefabricated structure, analysis

This article analyzes the assessment of the signs leading to the possible destruction of the studied building structure. To determine the degree of influence of signs (or groups) on the level of structural failure in their direct diagnosis, it is possible to use a mathematical basis, in particular, the Bayesian approach. The essence of the implementation is to compare the probability of failure for each structure under study. The result of the work is to identify and describe not only the features of the relationship between each feature affecting the destruction of the structure and the calculated probability of destruction, but also their degree of influence on increasing or decreasing the probability of an accident. According to the estimates of the mathematical definition of the signs affecting the destruction of the building structure, it is possible to more objectively assess the effectiveness of the method used to check the condition of the building structure.

Keywords: construction and technical expertise, defects, reliability, diagnostic tasks, diagnostic methods, efficiency

The requirements for increasing the heat transfer resistance of enclosing structures of buildings and structures are continuously increasing. At the same time, a number of buildings cannot be insulated from the outside due to their protective architectural status. Homeowners also cannot make changes to the facade design in the volume of their apartment. The design of a thermal insulation panel for mounting on the inner surface of an apartment wall is proposed. A method for calculating the heat transfer resistance of an enclosing structure insulated in this way is given.

Keywords: energy saving, wall insulation, internal thermal insulation panels, method of calculation of thermophysical parameters

The problems of competitiveness of construction organizations and ways to solve them investigated. The factors limiting the business activity of construction organizations are highlighted and evaluated based on statistical data. Three main categories and corresponding specific factors of competitiveness of construction organizations analyzed. The method of expert assessments revealed the degree of their influence on the competitiveness of the organization. The ways of increasing the competitiveness of construction organizations, taking into account these factors, proposed.

Keywords: competitiveness, increasing competitiveness, factors of influence, construction organization, statistical methods, the method of expert assessments

Over time reinforced concrete construction tend to lose their strength properties. An important factor in maintaining the integrity of reinforced concrete structures is the compliance of the parameters of the erected structure with its design values and operating conditions. Otherwise, the likelihood of defects such as the formation of cracks in the protective layer and corrosion of reinforcement increases. There are methods for restoring reinforced concrete structures that can return the strength characteristics to the design level or even exceed it.

Keywords: restoration of the protective layer, repair, inhibitor, adhesion, corrosion, penetrating waterproofing, chemical anchor, foundation, shotcreting

The article discusses modern methods of conducting construction control (CS) as part of the implementation of the government program for digitalization of the construction industry. The prerequisites justifying the need for automation of the SC are presented. A review of the software used by Russian construction companies to transfer quality control processes into electronic format was carried out. Based on the completed review, a comparative analysis of the most significant and frequently used software functions is presented. The requirements for them have been formed. They are classified based on their integration into digital models of capital construction projects. This allowed the authors to develop an algorithm for conducting a QC taking into account all the requirements of regulatory documents and the interaction of the main participants in the construction process. It provides for automatic data transfer for the generation of as-built documentation in electronic form, the appointment of persons responsible for correcting defects, their photo and video recording with reference to the 3D model of capital construction projects.

Keywords: digital technologies, automation, regulatory documentation, as-built documentation, quality, construction processes, construction control, information model

The main properties of slag-alkaline binders were studied to determine their optimal composition. The possibility of controlling the properties of binders developed on the basis of phosphorus and blast furnace slag by introducing corrective additives into the aluminosilicate component of slag-alkaline binders, as well as by changing the type of alkaline component, has been experimentally proven. The conducted studies confirm the effectiveness of the use of sulfate-containing alkaline components for the production of slag-alkaline binders. As a result of the conducted experiments, slag-alkaline binders with an activity of 30 to 110 MPa were obtained. The possibility of regulating the properties of the developed slag-alkaline binders has been established. The required binding strength is achieved by adjusting the composition of the aluminosilicate component by introducing additives and the type of alkaline component.

Keywords: alkali-silk binders, slags, optimal composition, basicity, chromium peak, construction materials, reconstruction, work technology

This paper analyzes the shortcomings of the existing organizational and technological documentation, namely the construction organization project and the project of work production. It is concluded that the main task of organizational-technological documentation is to minimize construction risks at the earliest stage, to increase knowledge about the project and to transfer the process of development and decision-making to an earlier stage of construction. As a solution to these problems, it is proposed to consider the use of building information modeling technologies (BIM) in construction, and move to the development of digital construction organization project (4D model of the construction process), which is a digital information model of the capital construction object (3D model), the elements of which are interconnected with the work on construction production. Two projects where the building information modeling technology was applied and a digital construction organization project was developed are considered: construction of an underground tunnel and reconstruction of a power unit of a combined heat and power plant. The advantages of using a digital construction organization project are proved, which makes it possible to forecast the planned duration of works, as well as the duration of works, taking into account the occurrence of risk events, necessary resources and equipment.

Keywords: digital project of construction organization, 4D model, building information modeling, project of construction organization, capital construction object

This article is devoted to identifying and analyzing the main factors that influence the effective overhaul of medical institutions, which have a great impact on the quality of life of the population, but do not meet modern standards and new trends of the Industry 4.0 concept. During the study, a comparative analysis of regulations governing the overhaul of medical institutions was carried out, design and working documentation was studied, and practical examples of the implementation of such projects were analyzed. As a result of the study, the most significant factors influencing the effectiveness of capital repairs of healthcare facilities were identified. Identified factors include: the lack of a modern legislative framework on capital repairs, insufficient quality of project documentation, ineffective planning and execution of capital repair projects, and lack of consideration of innovative approaches and technologies. These factors entail a number of additional risks, leading to increased costs and timing of work, as well as a decrease in the quality of work performed. In conclusion, recommendations are presented for optimizing the process of carrying out major repairs of medical institutions, including a detailed study of regulatory documents in order to update them in accordance with modern needs, and the involvement of a technical customer for the purpose of control from the initial stage to the commissioning of the institution.

Keywords: major repairs, healthcare facilities, medical institutions, modern standards, project documentation

Technological pipelines of compressor stations are one of the significant types of basic equipment that ensures uninterrupted operation during gas transportation. In this article, we paid special attention to the issue of safe operation of the pipeline strapping of the gas treatment plant for transportation, which is designed to dry gas to the required parameters required by consumers and is one of the main technological units of the compressor station. During the operation of the adsorber lines with "hot" and "cold" gases, the pipelines of the regeneration line are subjected to high variable temperature loads. Thus, the operating organization faces the problem of ensuring sufficient compensation for the linear expansion of technological pipelines during their periodic heating. The calculation of the service life of the piping and its stability with a matched axial bellows compensator has been performed. Various solutions to the reliability problems of these compressor station components are considered and analyzed. It is concluded that it is necessary to update the regulatory design framework and introduce continuous technical monitoring methods into the operated facilities.

Keywords: gas treatment plant, process pipeline, adsorber, safe operation period, temperature load, compensator

the effect of a thickener and a setting retarder on the technological properties of GSHS START is investigated. One-factor plans of a two-factor model have been developed, with a minimum (0.1%; 0.005%) and maximum (0.2%; 0.05%) dosage levels of pore-forming and water-retaining additives, respectively. Regression equations of output parameters in the form of a second-degree polynomial are obtained using regression and correlation analysis of experimental data. The values of partial correlation coefficients are analyzed. With an increase in the dose of water-retaining and pore-forming additives from 0.1% to 0.2% and from 0.005% to 0.05% of the binder, respectively, for all possible combinations of the dosage of the thickener and setting retarder, there is an increase in setting time by 10 ... 72%, and sliding by 33 ... 80%. The least sensitive to an increase in water-retaining and pore-forming additives was a mixture in which the amount of thickener is 0.2% (at the upper level), and the amount of moderator is 0.04% (at the lower level).

Keywords: technological properties, organizational and technological solutions, dry building mixes, functional additives, thickener, setting, retarder, two-factor experiment, coefficient of determination, regression analysis, correlation analysis

Methods of calculation and design of building structures are considered that make it possible to provide trouble-free operation on time during the service life, and hence the level of reliability. According to the reliability indicator, the following scheme for standardizing the reliability of designed building structures is linked to the assessment of quality indicators of constructed structures. Indicators of design quality that are not related to strength, guaranteed with a given probability of failure-free operation, are introduced: geometric dimensions, modular deformation and elasticity, taking into account the properties of variability and technology. The appropriate safety factors are determined, ensuring mandatory protection of failure-free operation. A scheme for calculating design structures with the required level of reliability during the design, construction and operation of structures is being developed.

Keywords: method of calculation of structures, reliability, safety factor, strength class, reliability index, improvement of calculation of structures

The article discusses methodological approaches to assessing the quality of work projects (WPP). Based on an analytical review of modern scientific articles and regulatory documentation, it is shown that PPR is subject to a significant amount of uncoordinated requirements, both in terms of content and the availability of approvals for various conditions of construction sites. At the same time, projects are increasingly of a formal nature, the quality of technological solutions is decreasing, and third-party developers, so-called freelancers, are involved in their preparation. In this regard, the goal of the research work is formulated in the form of developing a methodology for analyzing the quality of PPR. Based on the analysis of various methodological approaches, it was established that it should be based on the assessment of various indicators obtained from projects drawn up for the conditions of specific construction sites, design features of buildings and structures being erected, etc. It is shown that the assessment of PPR should be carried out on the basis of a single, measurable, comprehensive criterion, which includes the following factors: ensuring safe working conditions at the construction site and the integrated safety of construction processes for the surrounding buildings; compliance with technological discipline requirements; compliance of the technology used with the specific conditions of the construction site; sufficient completeness of the project, completed on the basis of the requirements of regulatory documents. It is proposed to translate qualitative information characterizing these factors into quantifiable indicators based on their analysis using general definition tables.

Keywords: organizational and technological documentation, work project, quality, efficiency, general definition tables, incoming documentation control

The relevance of the topic of the article is due to the fact that currently there is no linking of the calendar plan to the schedule for the development of capital investments. The principle of constructing a schedule for the development of capital investments is proposed, which ensures the uniformity and proportionality of the use of financial resources. Schedules for the development of capital investments are constructed, each schedule for the development of capital investments corresponds to an image describing the change in the absolute value of the profitability of the investment and construction project. The use of a mathematical apparatus describing the movement of a material point can be used in the development of investment schedules and calendar plans for construction. The construction of construction schedules in the section of the construction organization project based on investment schedules will have a significant impact on the economic efficiency of investment projects.

Keywords: construction schedule, investments, return on investment, development of capital investments, duration of construction, efficiency of capital investments

The article synthesizes several approaches to the development of the social environment of neighborhoods and clusters, taking into account scientific developments in assessing the potential of territories in terms of building density, number of floors and capacity saturation of schools, preschool institutions and production areas. Options for implementing the strategy are outlined based on multi-product models for calculating capacity and scientific and production potential for the development of territories.

Keywords: cluster, quarter, region, potential, strategic planning, production capacity, multi-product models, building density, schematic map, optimization

Girderless ceilings have become particularly popular in the construction of civil buildings. However, it is often necessary to reconstruct them, namely, to strengthen the joint of the plate with the column. Both domestic and foreign researchers deal with the issues of punching. This scientific article is devoted to the study of the method of strengthening reinforced concrete floor slabs by adding transverse reinforcement.

Keywords: floor plate, punching, transverse reinforcement, reinforcement

Reliable and safe operation of oil and gas pipelines in the conditions of the Far North and Siberia is an urgent task facing the Russian Federation. It has the most important economic and strategic importance. The climatic and geological conditions of these regions suggest a high degree of risk associated largely with seasonal temperature fluctuations and oil pumping technologies, leading to freezing or thawing of the soil, the appearance of thawed permafrost waters. The purpose of our study was to analyze the influence of extreme natural and operational conditions on the design and spatial position of pipelines during the operation of the section of the CPS-2 - NPS Urengoyskaya highway. It was found out that the studied section of the oil pipeline has a predisposition to failures due to unfavorable conditions: meltwater, heaving soils, swampy territory. Technological calculations allowed us to conclude that at this stage the pipeline route meets all the conditions of strength and stability, i.e. the reliability of the pipeline is ensured.

Keywords: hydrocarbons, pipeline, melt water, underground laying, strength calculation, stability calculation, permafrost soils, spatial location

Information technologies and systems are a promising tool for solving a wide variety of problems in the development and implementation of construction projects at the present stage. Their active use makes it possible to reduce the cost and time of project implementation, as well as improve the quality of work performed by creating a modern and effective construction control system.

Keywords: information technology, digital building model, information modeling, design, construction process