For the long-term operation of a power oil transformer, it is necessary to comply with all regulated checks of its technical condition, prescribed in the instructions. The current regulations provide for daily routine inspection and technical examination at least once a week. Famously, the heating of a power transformer during its operation is linked to the presence of active losses in the windings and core. High power transformers have impressive heat losses. Oil cooling systems are used to prevent that overheating of the transformer and damage to the insulation of the coil windings. The deterioration of the quality of the transformer oil causes an increase in active losses, due to which the efficiency of the power device decreases. This negatively affects the process of converting electrical en-ergy. The conclusion is that the quality of the oil directly affects the longevity of the power transformer. Thus, the most important functional elements from a control point of view are the transformer oil and the coil of the power device. Based on the foregoing, the urgent problem of technical control of electrical substations’ transformers is the development of methods and devices for express monitoring of the functional state of power oil transformers, which allow quick diagnostic information receiving, sufficient for a timely decision on the need for unscheduled repairs or maintenance.

Keywords: power transformer; transformer oil; impedance; diagnostics; functional state; dielectric loss tangent; equivalent circuit; MathCad

The trend to miniaturize and reduce the material consumption of modern electrical products of alternating current, places increased demands on the quality of their individual elements. All electrical products of alternating current (electromagnets, electromagnetic relays, motors) have a moving and fixed parts of the magnetic circuit and at least one working coil. During the operation of electrical products of alternating current, a current flows in the working coil, a working magnetic flux is created in the fixed part of the magnetic circuit, which sets in motion its movable part. The magnitude of the magnetic flux is determined by the design, the mutual arrangement of the parts of the magnetic circuit and the working coil, as well as the number of turns in it and the magnitude of the flowing current. During the working cycle of electrical products of alternating current, the moving part of the magnetic circuit moves relatively stationary, which also leads to a change in the magnetic flux. It is required to know their mechanical, electrical and magnetic properties. Each group of indicators requires the use of its own methods and means of testing electrical products of alternating current. This situation stimulates the search for the integral characteristics of electrical products of alternating current, which allow to draw conclusions about the quality of individual parts and operational properties of the entire product. The article proposes to use the web-ampere characteristic of the operating cycle as an integral characteristic of an electromagnet. To obtain the weber - ampere characteristic of electrical products of alternating current, it is necessary to influence the magnetic circuit with an external varying magnetic field and measure the magnetic flux arising in its cross section with a special sensor. When determining the weber - ampere characteristic of the working cycle, the electrotechnical product of alternating current in assembled form is subjected to testing, which makes it impossible to use magnetic flux sensors. Therefore, the use of existing measurement methods is not possible and therefore it is necessary to develop a method for determining the weber - ampere characteristic of the operating cycle of AC electrical products, which has acceptable accuracy and does not require the use of additional sensors.

Keywords: electromagnets, integral characteristics, functional state assessment, magnetic measurements

The article deals with building a seasonal model with a linear growth of the Winter’s statistic value, on the basis of which the parameters are calculated: the customs value index and the weighted average rate, which are the composition of the calculation formula of customs payments. To build the model, the monthly data of the customs statistics on imports of 28 commodity group “Products of inorganic chemistry; inorganic or organic compounds of precious metals, rare earth metals, radioactive elements or isotopes” of the Customs Nomenclature of the external economic activity of EAEU from 01.01. 2018 up to 31.12.2020 are used in the region of activity of the Southern Customs Administration.

Keywords: time series, econometric modeling, forecasting, adaptation parameter, seasonality coefficients, adaptive model

At the moment, in the conditions of an actively developing information society, information is becoming a necessary factor of production, therefore ensuring the safety of data is an important issue. The article is devoted to the topical, today, problems associated with threats in the field of data storage. The definition of the concept of threat in the field of data storage is given; classification by types of threats is proposed; the following classes of threats in the field of data storage are distinguished: spatial, communicative, destructive; the actual components of threats are described. Based on the analysis of threats in the field of data storage, algorithms for ensuring the safety of information will be developed in the future.

Keywords: information, data, data storage, data safety, data integrity, data storage threats, data integrity threats

The peculiarities of implementation of the process of digital transformation of the enterprise are considered. The structure of a digital balanced system of indicators is proposed, including a strategic map of digital transformation, key success factors and performance indicators. The conceptual structure of enterprise digital transformation management is given.

Keywords: digital transformation, strategic map, key performance indicator, key success factor, risk, management solutions, balanced scorecard, simulation model, strategy

As technology advances, supply chains have become complex and dynamic, and it has never been more important to adopt flexible and innovative approaches to managing them as in the heightened risk of the COVID-19 pandemic. The availability of data in real time, competent and timely planning, the ability to adapt to constantly changing market conditions have become more important competitive advantages than ever. Digital twins are a technological framework that focuses on digitalizing supply chains and presenting analytical capabilities to identify risks, predict them in a digital model for rapid response in the real world.

Keywords: supply chains, risk management, digital twins, logistics, trucking, modeling

Hydrolysis lignin is a waste product of hydrolysis production (wood that has undergone thermochemical treatment). Lignin is of particular interest in the production of building materials, since it is unique in its chemical composition and physical properties. At the same time, the use of lignin at the present time will reduce the technogenic load on the environment, since the dumps of this waste occupy large areas, harming the ecology of cities. The purpose of this work is to study the possibility of obtaining effective ceramic products based on production waste for external enclosing structures. The article presents the results of determining the optimal percentage of the content of the burnout additive in the production of porous ceramics. The work shows the dependence of the change in physical and mechanical properties on the content and composition of the additive. It is shown that the best indicators are characterized by compositions with a 1: 1 content of lignin and sawdust in addition. The authors investigated shrinkage deformations during ceramics firing and drying. It is shown that when using the hydrolysis lignin of the Ust-Abakan plant, there is no loosening of the samples during sintering.

Keywords: waste, recycling, hydrolysis lignin, ceramic products, sawdust, porosity, shrinkage, density, water absorption

To determine the optimal set of machines for the production of earthworks in urban conditions, it is necessary to make a multi-criteria selection of the set among possible combinations of machines, with each parameter having a certain level of influence. To determine the weight of the parameters, it was decided to conduct an expert survey. The minimum number of experts was determined, a survey was conducted, after which the data was processed, the level of consistency of the expert opinion was obtained, and the level of influence of each parameter on the choice of sets of machines was revealed.

Keywords: parameters that affect the choice of machine sets, expert survey, Kendall concordance coefficient, earthworks, Pearson coefficient

Based on the Bayes approach, a representative number of experimental measurements was determined when assessing the quality of the environment, in particular, when monitoring the quality of the atmosphere and checking the compliance with the standard for the accumulation of solid municipal waste

Keywords: Bayesian approach, quality control, experimental measurement, a priori data, a posteriori data, distribution density

Of the industries that consume industrial waste, the construction materials industry is perhaps the largest. The research has determined that the use of industrial waste can cover up to 40% of the construction needs for raw materials. The use of industrial waste reduces the cost of manufacturing construction materials compared to the production of their natural raw materials by up to 30%. The achieved savings in capital investment is approximately 35 ... 50%.

Keywords: industrial waste, effective additives, cost reduction, performance improvement, environmental problem solving

The quality of atmospheric air in residential areas of settlements and human health largely depends on the main indicators of aerosol particles. The purpose of this work was to study aerosol parameters (number and mass fraction of particles; surface density of particles) and specific pollution of the territory of the settlement of Sredny Akhtuba, Sredneakhtubinsky district of the Volgograd region under conditions of anthropogenic load of construction industry enterprises in 2018. Research objectives: selection of leaves of apricot trees with expected dust-like particles in Srednyaya Akhtuba and in a conditionally clean zone (gardening non-profit partnership (SNT) "Oroshenets", "Shelf"); preparation of aerosol suspensions; study of the mass fraction of particles D (dp),%; the number of particles (Np,%); the index of the surface density of aerosol particles (m0, μg · cm − 2) in the green infrastructure; calculation of the specific area of ​​the total pollution of the territory of the Srednyaya Akhtuba rn by particles, including fine dust (PM2.5; PM10). The conducted studies allow us to conclude that the specific area of ​​aerosol pollution in the territory of the Srednyaya Akhtuba rn is 3 times higher than in the conditionally clean zone. The surface density of particles (РМ2.5) on the territory of the Srednyaya Akhtuba rn is 108 higher than the values ​​in comparison with the conditionally clean zone (SNT "Oroshenets", "Shelf"); PM2.5-10 - 28 times; coarse dust (PM> 10) - 2 times more in the Srednyaya Akhtuba region than in the conditionally clean zone. The number of PM2.5 particles in the average Akhtuba rn is not much higher than the value of the conditionally clean zone - only 1.76 times; the excess in the number of particles (PM2.5-10) is only 1.19 times, i.e. practically, the studied indicators are at the same level; coarsely dispersed dust (PM> 10) - 4 times more in SNT than in the middle Akhtuba region. It is alarming that the number of fine particles in both zones does not differ much from each other and are practically at the same level, especially according to PM10, but their mass fractions and conditional masses differ noticeably, since in the middle Akhtuba they are heavier in weight, 108 times ... This may indicate that in fine particles from the rn Srednyaya Akhtuba compounds of metals and / or semimetals with significant atomic weight can be present, which requires further research and interpretation of the results obtained. A high amount of dust-like particles in a conditionally clean zone - SNT “Oroshenets”, “Shelf”, indicates that this zone is “conditional” due to probable natural pollution, expressed by possible fluid activity of the Earth and removal of particles from its interior , gases and other pollutants that enter the atmospheric air of SNT. In this regard, in terms of the amount of fine dust, SNT is on the same level with the rn Srednyaya Akhtuba. The studied territories are of interest for further research and refinement of the results obtained, including the search for a possible source of natural pollution in both territories to ensure the environmental safety of the population living there and reduce environmental risks.

Keywords: dispersion, aerosols; surface density of particles; PM2.5; PM10; green infrastructure; natural pollution

The purpose of the study is to determine an effective modifier of the structure of a slag-alkaline stone, characterized by a low value of linear shrinkage and a decrease in cracking in the early stages of hardening. Ground blast furnace slags were activated with aqueous solutions based on sodium silicate and caustic soda. Fly ash and zeolite-containing clay were used as modifiers of the cement stone structure at a dosage of 5, 10 and 15% of the binder consumption. The results of the study showed that an increase in fly ash content does not significantly affect the setting time. The use of zeolite-containing clay as a slag-alkali binder modifier makes it possible to regulate the setting time of the binder at a dosage of more than 10%. Cracking of the slag-alkaline matrix was observed only for mixtures without fly ash and zeolite-containing clay.

Keywords: cement stone, slag-alkali binder, hardening activator, structure modifier, fly ash, zeolites, shrinkage, cracking

The issues of construction and practical application of 4D BIM models relate to the current issues of the development of organizational and technological design of construction at the international level. The purpose of the work is to describe the information model of the construction process on the example of brickwork. To achieve this goal, the following tasks are solved: the structure of the source infor-mation necessary to describe the changes in the construction process in space and time is developed; analytical dependencies describing the changes in the construc-tion process in space at each moment of time are obtained; the procedure for evaluating the effectiveness of organizational and technological decisions made by the designer and contractor when performing bricklaying is given. The methods of algebra and analytical geometry were used in the research. As the initial informa-tion, the data provided in the national classifier of construction resources and the register of estimated reserves are used. Analytical models are formed as a result of applying a systematic approach and methods of mathematical logic. Conclusions: 1. To build an information model of a separate construction process, it is advisable to use the existing base of estimated standards in construction. 2. It is recom-mended to apply the well-known equations describing the change in duration from the volume of labor and material and technical resources. 3. Evaluation of effi-ciency using the information model involves a comparison of at least 13 variants of the organization of work on the device of the brick masonry.

Keywords: construction process, construction duration, construction information model, labor productivity, machine productivity, leading construction machine, machine useful power utilization factor, labor resources, material and technical resources

Crushed stone-mastic asphalt concrete is a more durable material compared to traditional asphalt concrete. But for its exploitation, high-quality mineral powders and bituminous carriers are needed to prevent bitumen from flowing out of the composition. Today, the carbonate rock powders and bituminous carriers from natural cellulosic fibers are widely used. However, many Russian Federation regions, including the Krasnoyarsk Territory, are not provided with these materials, and they are also really expensive. The purpose of our work was to reduce the cost and improve the properties of crushed stone-mastic asphalt concrete. The task of the research was to develop gravel-mastic asphalt concrete compositions using the industrial waste from the Krasnoyarsk Territory. Nepheline sludge was tested which is the waste of the alumina plant in Achinsk and rubber crumb with inclusions of cord fiber of Chernogorsk in Krasnoyarsk Territory. The chemical composition and physical and mechanical properties of these wastes were studied. Gravel-mastic asphalt concrete compositions were made by using these wastes. The tests showed that the received compositions met regulatory requirements. The developed compositions were introduced by “Krasnoyarskavtodorom” on the Krasnoyarsk Territory roads. The economic effect of the waste usage is achieved through the exploitation of the local raw materials, which leads to a reduction of the transportation and energy costs.

Keywords: the crushed stone-mastic asphalt concrete, industrial waste, nepheline sludge, mineral powder, bituminant, rubber waste with corded fiber inclusions, crushed stone, sand Crushed stone-mastic asphalt concrete, industrial waste, nepheline sludge

The article deals with measures to preserve the ground bases of structures in a frozen state. It is shown that the methods of soil screening are cheap and do not use special equipment. These methods use different types of insulation: natural and artificial. The existing technologies of the device of thermal insulation screens on highways and engineering structures are described. It is proposed to replace polyurethane foam with extruded polystyrene foam. These materials are described and their physical properties are compared. The technology of the device of the heat-insulating coating is given.

Keywords: geoplites, expanded polystyrene, polyurethane foam, thermal insulation screen, foundations, permafrost soils, geotextiles,moss cover

This article discusses various options for carrying out construction and installation works during the technical re-equipment of energy-processing equipment in the building of the Main Building of the existing CHPP. The methods of installation of large-sized equipment to the design mark are studied by three different methods with a description of the features of the work and the characteristics that affect the cost of the work. The enlarged schedule of construction and installation works on technical re-equipment of the boiler drum is given.

Keywords: thermal power plant, technical re-equipment, construction and installation works, technological equipment, large-sized equipment

The article analyzes the results of experimental studies of prestressed steel I-beams. Presented specific features of the stressed and deformed states of welded steel beams, prestressed by wall stretching and bending of the initial T-element. In the first method, the prestressing in the beam was created by mechanical stretching of the wall on a special stand. In the second method, the T-piece is loaded by external forces applied to the T-bar plate until normal stresses appear at the bottom point of the wall, equal to the design resistance of low-carbon steel, then the second belt plate is welded to the T-piece element. The results of a numerical experiment with these beams, carried out in the SP LIRA, are considered. Presented a comparative assessment of the results of numerical and full-scale tests of prestressed I-beams a similar section with bimetallic beams without prestressing.

Keywords: web stretching, T-beam bending, section asymmetry, numerical experiment, test stand, stress, bearing capacity, beam rigidity, bending deformation, local stability

In Russia, the legislative requirements of the municipal authorities of all regions are gradually becoming mandatory in the field of dismantling trade pavilions illegally installed on urban lands, which is why this article is so relevant. The article deals with the problems of determining the capital of trade pavilions in the judicial construction and technical expertise. An example from practical activity is given. The term "capital structure" is also considered and signs of capital are displayed.

Keywords: capital structure, construction, judicial construction and technical expertise, trade pavilions, construction expertise

During the heating period in many Siberian cities, there is a low quality of atmospheric air. One of the main sources of air pollution is the private sector, since most individual residential buildings, existing and under construction, do not meet modern standards for the thermal protection of buildings, and as heat generators they use furnaces and boilers that do not have an environmental class in terms of emissions of pollutants. Individual residential construction does not require the preparation of project documentation, therefore, each home owner independently decides on the parameters of the building, including its thermal protection. However, in the minds of ""self-builders"" there is often no understanding of how the leakage of thermal energy occurs through the building's enclosing structures and their junctions. In the article, firstly, standard solutions for insulation of enclosing structures of low-rise buildings were considered; secondly, the payback period of these solutions was determined depending on the thickness of the thermal insulation layer and taking into account the cost of additional materials; thirdly, the payback period of various solutions was compared and the most quickly recouped ones were selected. In the course of the study, it was found that the costs of measures to strengthen the thermal protection of the enclosing structures of an individual residential building can be compensated by a future reduction in the consumption of brown coal or other energy carriers, which will also reduce the emissions of pollutants into the atmosphere. At the same time, the greatest energy-saving effect is achieved from the insulation of the attic floor and the underground space, since it is not required to use expensive facing coverings as on facades. The results of the study can be used as a recommendation when choosing the optimal thickness of thermal insulation when strengthening the thermal protection of the enclosing structure with the desired payback period.

Keywords: energy efficiency of buildings, energy audit of buildings, heat loss in low-rise buildings, energy saving measures, reconstruction of buildings, problems of coal-fired heating, reduction of air pollution, reduction of CO2 emissions

Blasting operations are often the only way to prepare the material for the recess for laying roads and railways in the rocks. Explosive loosening is also used to extract stone as a building material. Field testing is costly and often dangerous. Therefore, it is necessary to first conduct a series of experiments on the model and find out the conditions for ensuring good quality loosening of rocks. In order for the results of model tests to be transferred to nature, a similarity between model and specimen is required. The approximate similarity is achieved by the equality of the similarity criteria for the model and specimen. The characteristic similarity criteria are obtained by analyzing the physical quantities inherent in a mechanical system using the theory of dimension and similarity. The received criteria are presented in the classical form. These are the criteria of Strouhal, Froude, Cauchy and Newton.

Keywords: explosive loosening, rock material, deceleration interval, similarity criterion, modeling, rock density, model, specimen, expansion height, dimensionality, physical quantity

The article discusses the opportunities that arise when using data mining methods in construction. A numerical experiment is carried out to create an algorithm for making design decisions in the production of zero-cycle works, namely, when installing the enclosing structures of the pit edge. Comparison of the data obtained in the Deductor Studio software product with those actually used in the construction of a residential building is performed.

Keywords: construction, earthworks, information technology, decision tree, design decision making, data analysis, machine learning, Data Mining, Deductor.

The possibilities of using advanced software for effective analysis and design of building structures are currently being explored. Rapid assessment of the state during design, assessment of the ability to resist any of the loading environments. The finite element method possesses these qualities. In this article, a nonlinear FE analysis of cold rolled steel beams Z-profile under bending load using ANSYS software. The bending resistance of two types of beams is compared, a Z-beam with hollow flanges and a Z-beam with solid flanges. A beam with hollow flanges exhibits better deformation characteristics than a solid one. Based on the analysis, the following conclusions are drawn: The proposed hollow flanged element shows better resistance towards deformation; Since the hollow section follows a single profiled failure pattern the point of failure is extended; The stiffness of hollow flanged Z section is nearly four times greater than that of solid flanged Z section.

Keywords: efficient analysis, finite element method, Z-profile, deformation characteristics, nonlinear FE analysis

The article presents dependencies between deformation characteristics of SFRC with a high-strength cement-sand matrix from the type of steel fiber and its volumetric content. It was found that the introduction of fiber imparts plasticity to the matrix. Plasticity depends more on the type of fiber than on its amount per unit volume. Full deformation diagrams of steel fiber reinforced concrete have a descending branch, in contrast to the matrix diagram. The introduction of steel fiber increases the deformations corresponding to the ultimate tensile strength by no more than 75%. Deformations of the descending branch of the diagram, depend on the type of fiber, characterizing the plastic properties of steel fiber reinforced concrete. At the same time, it essential how fiber ensures the adhesion to the matrix: along its entire length due to its fiber profile or due to the design features of the anchors at its ends.

Keywords: axial tension, complete diagram of deformation of steel fiber reinforced concrete, type of fiber, percentage of fiber reinforcement, ductility, residual strength

Determination of the actual category of the technical condition of building structures is the main purpose of the survey. At the same time, the reliability of the survey results depends on the volume of instrumental measurement of the monitored parameters, which should be minimal, but sufficient to obtain data with a given level of security. This article presents a methodology for de-termining the scope of control based on a statistical approach with justification of the necessary and sufficient number of tests for each type of survey. The approbation of the described approach in the survey of precast concrete ele-ments is presented. The proposed methodology is based on a statistical approach adopted at the international level, which allows work to be carried out in other countries.

Keywords: inspection of building structures, instrumental control, statistical justification, precast concrete