Table of contents

BUILDINTECH BIT 2021. INNOVATIONS AND TECHNOLOGIES IN CONSTRUCTION

PREFACE

It is our pleasure to welcome you the Second International Scientific Conference "BuildInTech BIT 2021. Innovations and Technologies in Construction" during March 9-10, 2021, in Belgorod State Technological University named after V.G. Shukhov, Belgorod, Russia.

The conference provided a valuable opportunity for researchers and industry experts to exchange their ideas face to face. Proceedings brings both industry and academia and includes reports of scientists, representatives of the construction industry and postgraduate students from different technical universities not only from the Russian Federation (28 Russian institutes and universities).

The conference was also attended by representatives of the near and far abroad from 11 countries of the world (Iran, India, China, Lithuania, Azerbaijan, Kazakhstan, Uzbekistan, Belarus, the Ukraine, Georgia, and Abkhazia). Such wide geography of the conference participants, on the one hand, is very valuable from the point of view of the possibility of exchanging experience and knowledge on the issues of construction, building materials, as well as their application in various sectors of the construction industry. On the other hand, such a wide geography of the participants confirms the relevance of the thematic areas touched upon within the conference.

List of Conference Editors, Organizing Conference Committee, Scientific Conference Committee are availble in this pdf.

BUILDINTECH BIT 2021. INNOVATIONS AND TECHNOLOGIES IN CONSTRUCTION

All papers published in this volume of Journal of Physics: Conference Series have been peer reviewed through processes administered by the Editors. Reviews were conducted by expert referees to the professional and scientific standards expected of a proceedings journal published by IOP Publishing.

• Type of peer review: Single-blind / Double-blind / Triple-blind / Open / Other

(please describe): Double-blind.

Papers must be submitted electronically via: https://scopus-conf.ru/en/buildintech-bit-2021 -innovacii-i-tehnologii-v-stroitelstve/#registration. All submissions must come in PDF format, conform to the Conference Publishing template, and not exceed 14 pages (including figures, appendices and references). We also welcome survey papers with an increased page limit of up to 15 pages. Together with papers authors also must submit the registration form. Every participant in the conference served by this site, "in any capacity," must maintain a login and password. The same login must be used for all conferences. Follow the link to register a login, to check and update your personal information, or to retrieve your password. To comply with the General Data Protection Regulation, the first time when you login to a new account, you will be directed to the required opt-in consent form before you can use your account in any capacity for products and services offered through this site. All papers submitted to the conferences supported by this site need to be prepared as compliant PDF files and must be formatted according to the template.

• Conference submission management system: the papers were submitted via conference website

• Number of submissions received: 160 submissions received

• Number of submissions sent for review: 117 submissions were sent for review

• Number of submissions accepted: 85 submissions were accepted

• Acceptance Rate (Number of Submissions Accepted / Number of Submissions Received X 100): 53%

• Average number of reviews per paper: 3

• Total number of reviewers involved: 45

• Any additional info on review process: All the papers submitted to the «BUILDINTECH BIT 2021. INNOVATIONS AND TECHNOLOGIES IN CONSTRUCTION» conferences pass the procedure of reviewing according to the order established by editorial board. All papers are reviewed three times by experts in relevant field. The reviewing process took 40 days. The revised papers were also checked by Editors. All accepted papers meet the following criteria:

- Scientific merit and quality of data presented;

- Relevance of study to the conference topics;

- No plagiarism and autoplagiarism;

- Adequate paper structure;

- Good English.

Members of the editorial board and leading Russian and international experts in corresponding areas of life sciences, invited as independent readers, perform peer reviews. Conference Editors choose readers for peer review. In the case of the manuscript relevance to the conference profile, established rules and requirements, it is accepted by the editorial board and is sent for the reviewing. Otherwise the article is rejected without further reviewing. Reviewers prepare reviews of articles on a voluntary basis. Reviewers should submit their reviews in a scanned form. The reviewer makes a conclusion about the possibility of publishing an article:

• "recommended for publication";

• "recommended taking into account the correction of the comments made by the reviewer";

• "article must be sent for revision";

• "not recommended for publication".

The articles are reviewed and accepted only after at least two positive reviews of three reviewers. After making a decision by the editorial board of the conference to admit the article for publication, the author is informed about it.

• Contact person for queries:

Name: Sergey Klyuev

Affiliation: Candidate of Engineering Sciences (PhD), Associate Professor, Belgorod State

Technological University named after V.G. Shukhov

Email: Klyuyev@yandex.ru

Abstract During the construction of underground storage of hazardous waste, it is necessary to create waterproof walls in the ground. The grout is filtered in the rock, fills the pores and, when hardened, creates a reliable barrier to groundwater. A one-dimensional model of the flow of inhomogeneous particles in a porous medium is considered. The retained particles profiles formed during deep bed filtration are studied. It is shown that when filtering a 2-particle suspension, the deposit is distributed unevenly. The profile of large retained particles is always monotonous, and the profile of small retained particles is nonmonotonic. The monotonicity of the total deposit profile depends on the model parameters. The shape of non-monotonic profiles is time-dependent. At short times, the profile decreases monotonously. At some point, a maximum appears on the profile graph, which shifts from the inlet to the output with increasing time. When the maximum point reaches the outlet, the profile becomes monotonically increasing. With a further increase in time, the retention profiles remain monotonically increasing. Analytical solutions for a filtration model with particles of three or more different types are unknown. Analysis of the retention profiles of the polydisperse suspension requires further study.

The paper investigates the fresh and hardened mechanical properties of a concrete mix produced with partial or full substitution of natural aggregates with recycled aggregates from demolition works and crushed tested cubes concrete from laboratory. Recycled aggregate concrete (RAC) is the concrete that has been made from waste materials recycled as coarse and/or fine aggregate. One of the waste materials is the concrete that is taken from demolished buildings in Iraq due to military operations on 2014 and the other is crushed tested concrete cubes from laboratory. Choosing crushed concrete wastes from demolition works and crushed test cubes concrete from laboratory as source of recycling would result in reusing portion of the waste products of the concrete production industry. This study presents an experimental study on the performance of concrete that contains recycled coarse aggregate. The replacement percentages of natural coarse aggregate with the recycled coarse aggregate are (0, 33.3, 66.7 and 100) %. Moreover, silica fume was used as an admixture for all recycled aggregate concretes. Compressive and indirect tensile strength were studied for all of the reference and recycled aggregate concretes at (28) days age, by testing concrete cubes and cylinders specimens respectively. The results showed that the compressive strength and splitting tensile strength decreased for recycled waste concretes taken from demolished buildings and increased for recycled crushed tested cubes concretes from laboratory as compared to the reference concrete. When the silica fume was added, the compressive strength and tensile strength increased for all recycled aggregate concretes compared to those without the silica fume.

Biogas technologies as an alternative energy source are widespread in the EU countries. But on the territory of the Russian Federation, this process is poorly understood. Since the potential from the use of biogas technologies is significant, a combined substrate mixing system has been proposed. Computer simulation of various mixing parameters was carried out and optimal modes were determined. As a result of a series of computational experiments, it was found that the developed mixing system allows the mixing time to be doubled in comparison with the traditional mechanical mixing system in a cylindrical bioreactor. At the same time, the uniformity of mixing is 16% higher. The volume of stagnant zones is 2.72 times lower. The obtained results give grounds to assume about a possible improvement of the habitat for microorganisms and, as a consequence, an increase in the rate of their distribution in the bi-oreactor, which in turn increases the rate of fermentation and the volume of biogas produced.

Reliable and safe operation of hydro-technical structures (earth dams), in the seismic regions of the republic, requires researchers to constantly improve the calculation methods in accordance with the requirements of regulatory documents for basic and special combinations of loads, including seismic ones. A calculation method is proposed for estimating the stress state on the example of an earth dam of the Charvak HPP (in operation for 47 years) in a plane elastic statement under main loads, taking into account the real piecewise-inhomogeneous physical and mechanical characteristics of soil of the structure body. Individual results of solving the problem were compared with the data of long-term field observations. The calculation method allows determining the kinematic characteristics (displacements, settlements, stresses, pore pressure) of an earth dam, which makes it possible to predict the state of the most vulnerable places in the structure and, if necessary, to develop appropriate measures to strengthen them. The problem was solved by the numerical finite element method. According to the developed technique, the problem by the numerical finite element method was reduced to solving a system of linear equations relative to the desired displacements. The calculation results are presented in the form of isolines of the stress-strain state of the dam body under the main loads (gravitational forces, hydrostatics). The numerical results of solving the problem and their comparison with the data of field observations make it possible to determine the reliability of the developed methods and software and thereby determine the vulnerable zones of the earth dam, where the loss of stable operation of the structure is possible. Based on the research results, appropriate recommendations were made.

Carrying out rituals in the church hall of the cathedral is accompanied by a significant release of various hazards from parishioners and staff (heat, water vapor, carbon dioxide), when burning candles, from the use of censers and lamps (heat, carbon dioxide, fumes, soot, soot, water vapor), from consecration and solar radiation through external enclosures (heat). In the article, a local exhaust ventilation system with the use of umbrellas installed above the candlestick tabletop is proposed for trapping and removing harmful emissions from burning candles in a worship hall. To calculate air changes, it is important to have data on the amount of harmful substances emitted in the church hall of the cathedral. It is known that in the central part of the cathedral during the warm period of the year in the hall of worship at the permissible internal air temperature from 12 to 16 ° C and the optimum temperature from 14 to 16 ° C, one person emits an average of 50 g / h of water vapor. In the cold period of the year, when the permissible internal air temperature in the worship hall is from 12 to 16 ° C and the optimal temperature is 14 to 16 ° C, each parishioner emits on average up to 40 g / h of water vapor. Heat release from one person in full heat reaches 80 W in the warm season, and up to 100 W in the cold.

Nowadays a huge number of industrial buildings constructed in the last century need restoration. Structures with brick walls are in the list. The reason for this is the appearance of cracks, breaks, spalls, cavities, holloes and other discontinuities of brickwork; wall deformations; stratification of brickwork rows; humidification of walling, weathering and leaching of mortar; loss of individual bricks; damage to protective and finishing layers; efflorescence on the surface of brickwork and many other things.

The causes of such defects can be the following: unsatisfactory operating conditions; errors at the design stage; low quality of the used construction material; substandard work; differential settlement of walls foundation; violation or lack of wall waterproofing; natural aging of masonry and other negative factors.

In this work the object of the inspection was a brick wall of the main building of the sugar factory, which was put into operation in 1962.The inspection results showed that the condition of the load-bearing brick wall of the sugar factory main building, taking into account the scope and danger of defects, the degree of physical and moral wear of structures, as well as a number of other factors, can be considered unsatisfactory (limited working capacity) and the building can be regarded suitable for reconstruction and further operation.

The work is aimed at identifying the most effective methodology for short-term forecasting of energy consumption concerning intervals of 1 hour to 1 week based on the employment of im-proved fuzzy recurrence and long short-term memory neural networks. The object of research is a residential area with an uneven consumption of electrical energy. The article discusses methods for forecasting electrical load on the example of a residential area. The existing methods of forecasting were analyzed and the day-ahead and intra-day power forecast were reviewed. The list of relevant sources was presented.

On the basis of the reviewed literature in this area, the most effective and modern methods were identified that allow determining the consumption of electrical loads in residential and industrial buildings with an accuracy of 98 percent. Tables were developed reflecting the effectiveness of the considered techniques.

The time horizons of the forecast of electric energy consumption are considered. Four categories of load forecasting were identified: long-term forecasting with a forecast interval of more than one year; medium-term forecasting with a forecast interval from one month to one year; short-term load forecasting with a forecast interval from 1 day to several weeks.; operational forecasting, with a forecast interval from 1-2 hours to the end of the day. A comparative analysis of methods for predicting electrical load for intelligent network applications is carried out and its results are presented.

Solar power is almost a good idea for home owners interested in saving money on electricity costs and supporting a healthier environment. But there's no denying that some homes are more well suited to solar power systems than others. Your sun exposure, roof, climate, even state policies can influence how well you'll do with a residential solar power system.

It is true that the initial cost might be a bit heavy, but it makes more economic sense in the long run. This is a onetime expenditure that serves cost free for the next thirty years or so. And about its effectiveness, people should feel comfortable that the technology itself has been proven, as a reliable and clean energy source.

This article introduces the methodology and the results of an integrated design approach to optimize both structural system and building energy performance through architectural design process. The book titled Intelligent Design using Solar-Climatic Vision, introduced a number of practical and effective design approaches towards the creation of energy-efficient building façades as well as comfortable urban environments. Applying solar-climatic vision, especially during the procedure of optimizing tall structural systems, can develop sustainable frameworks that maximize thermal comfort while minimizing waste of resources.

Synthesis of alkyd resins is one of the most common technological processes for deep processing of vegetable oils. In Russia, about 700 thousand tons of alkyd resins are produced per year; so much attention is paid to improving the production process of alkyd resins. Production of synthesis of alkyd resins can be classified as fire and explosive hazardous. One of the main reasons for the high level of accidents in the synthesis of alkyd lacquers and resins is the lack of digitalization of control and management of synthesis. This paper discusses the possibility of using changes in the electrical properties of the reaction mass to control the flow of a chemical synthesis reaction. The principal difference between the proposed approach is that it is proposed to use measurements of DC values directly in the technological process. Studies have shown that it is more promising to use the analysis of the values of the complex resistance module of the reaction mass for the purposes of synthesis control. The advantage of this solution is that the method is more informative, as observations are made in a two-dimensional space of complex values rather than in a one-dimensional one. When using high-frequency alternating current, the module and phase of the complex resistance of the reaction mass are controlled, as well as a number of other parameters (leakage current, q-factor, etc.)

The issues of wear of disk vibrating working bodies of smoothing machines are considered. It is shown that during friction of the working body against the concrete mixture, mainly abrasive and less oxidative wear occurs. In this case, the amount of wear is proportional to the smoothing capacity of the working body, the operating time, the specific pressure of the working body on the surface of the concrete mixture and the coefficient taking into account the working conditions. It was found that the position of natural and forced vibrations of the working body on the smoothing process leads to significant changes in the magnitude and nature of the disc wear. It was determined that the general one-sided character of the disk depends on the parameters of forced vibrations generated by the working body. The presence of localized zones with an expressed wear of the disc was revealed. The latter reduces most significantly the quality of the surface treatment of the concrete mixture. The relationship between the presence of wear of localized wear zones and natural vibrations of the metal structure of the portal of the smoothing machine is shown. It is suggested that the issues of vibration protection (vibration isolation) in the broad sense of controlling the dynamic state of the smoothing machine as a technological complex are of decisive importance for the prevention or significant reduction of local localized wear of the working body.

Methods for calculating the moistening of textile fibers in the process of yarn production when processing with conditioned air with certain technological parameters based on mathematical modeling and numerical methods are presented. There are appropriate mathematical models, adequately describing the process of distribution of the relative air humidity in the porous medium under consideration. A mathematical model of the process of moistening porous of a textile material in the form of the Cauchy problem for a second-order differential equation for the purpose of numerical modeling of the change in the relative humidity of conditioned air in the volume of a compactly formed semi-finished product of textile production. The classical instability of the problem is shown, methods of its solution are considered, the problem is numerically solved for various options of technological conditions for organizing the humidification process. Numerical calculations have shown that the relative humidity of the air flow decreases monotonically with distance from the surface to a certain limiting value. At the same time, an increase in the specific surface area of a capillary-porous medium leads to a more intense drop in the relative humidity of the conditioned air in a moving air stream. The results of numerical studies show that with an increase in the flow rate of conditioned air, the depth of penetration of moisture into the volume of a porous medium increases, i.e. more moisture settles on the last layers of the volume. Consequently, to optimize the process, one should choose an air flow rate that provides a sufficient intensity of material moistening with deep penetration of moisture into the volume of a porous medium. Mathematical models of changes in the air flow rate in the volume of a porous medium according to linear and exonential laws are presented. It is shown that taking into account the drop in velocity according to the exponential law allows one to obtain good agreement between the calculated and experimental data. Physical and mathematical modeling of the non-stationary process of moisture distribution in a textile material during its humidification with conditioned air for the case of diffusion kinetics of the humidification reaction in the form of a boundary value problem for the diffusion equation has been carried out. On the basis of physical concepts of the processes occurring at the boundary of a porous medium and in its volume, modeling equations and boundary conditions for the problem of calculating the unsteady distribution of moisture in a porous medium are formulated.

The production of Portland cement clinker is accompanied by huge dust release and the accumulation of huge amounts of aspiration and clinker dust in the dust collection system. The rational use of this high-quality corrected fine-dispersed resource is an urgent task not only in technological, but also in ecological terms. Aspiration dust cannot be returned to the technological cycle. It is taken out of the cement plant, disrupting the ecological situation of valuable agricultural land and mountainous landscape. Taking into account the fact that it can be used in its natural form, without an additional mechanical intervention, this will expand the material and raw material base for the production of alkaline cements. This paper presents the results of studies of the particle size distribution of particles in samples of dispersed material and the determination of the shape and size of cement dust particles. The reactivity of the investigated powders of technogenic nature has been proved. These characteristics of cement dust electrostatic indicate feasibility of these powders dispersed as component binders ligaments alkaline activation.

Due to the specifics of the distribution of forces in a two-span frame, it is necessary to increase the cross-sections of the central part of the girder, which negatively affects the consumption of steel for the production of the frame. To reduce the influence of the specifics of the distribution of internal forces on the weight indicators in the girder of a two-span frame, it is necessary to use innovative constructive ways of distributing forces in the girder of the frame, which affect the reduction of material consumption. Such structures include the two-span frame with T-shaped supports proposed in this article, the calculation method of which is based on the idea of combining functions. Since the design is a newly proposed one, it is necessary to identify its stress state. Experimental studies are one of the ways to identify the stress state. The experimental research methodology is presented in the article. This article proposes an assessment of the stress state of a new structural form of a frame with T-shaped support. The development of the section method and the finite difference method makes it possible to evaluate the stress state of the frame from the deformations measured in the experiment. The accuracy of this method is 2...6 %. The proposed technique will make it possible to assess the stress state of a new structural form of a frame with T-shaped support using measured deformations, which were determined as a result of experimental studies, as well as when assessing the stress state of operating frame structures.

The improvement of methods and technologies for the production of dry building mixes, dispersed modifiers, dry paints and other finely ground, homogeneous systems is associated with the quality of their compositions, which, in turn, requires the use of high-tech energy-saving equipment. The use of the original pneumatic mixers proposed in the paper makes it possible to obtain high-quality multicomponent mixtures due to the specially organized movement of the two-phase flow meeting with the peripheral supply of the energy carrier. Forecasting and analyzing the dynamics of two- and multiphase systems distributed in the air in units of this type allows assessing the nature of the technological process of mixing components, while a mathematical description of the complex movement of particles in the air flow allows obtaining a result that helps to characterize the operating modes of the pneumatic mixer, which is important when operating this machine in production. The paper presents a method for numerical simulation of the axisymmetric motion of a two-phase flow in the homogenization chamber of a pneumatic mixer, which allows setting adequate operating modes of the unit for various dispersed systems mixed in it. The main assumptions in the construction of the mathematical model are also reflected, the conditions for setting the problem for this study are formulated, and the results are obtained in the form of analytical expressions of the main dynamic parameters of the flow with particles for the volume of the mixing chamber, depending on the design features of the pneumatic mixer.

Effective management of real estate complexes, which determines the minimum cost of ownership of constructed and operated objects, implies at the present stage the active introduction of information modeling technologies into the project life cycle. At the same time, in all the variety of modeling software and modeling formats offered by the national and foreign markets, those that have advanced controllability and adaptability to the changing conditions of the design or actual construction stages are the most effective for the purposes of managing the capital intensity of a non-movable asset. The ARCHICAD software package, which is a recognized leader in architectural modeling software, contains the necessary standard and additional tools for creating parameterized objects - elements of a real estate object that have the required properties, significantly accelerating and simplifying the work on adapting the model and optimizing space-planning solutions created on its basis. The authors created a universal parameterizing library feature of wall panel of precast technology in private residential construction, which implements a modular approach to parametric modeling using encapsulation basic library features to upgrade effectively the panel, to implement the specification of resources, visualize technology, including the virtual reality environment, providing the necessary visibility when training for line personnel of the construction site and technical quality control of construction products. The estimation to reduce the complexity and growth performance of work implementation of the proposed approach when designing a wall barrier of low-rise residential buildings.

The paper presents studies of cement-ash binder in the composition of concrete with the use of a complex modified additive (CMA). The research is aimed at improving the conditions for the production of concrete works, in particular, improving the workability of a concrete mixture based on ash-cement binders. The main evaluation criterion of the study was the change in the viscosity of the composition with a change in the water-binding ratio. The measurements were carried out in two stages: at the first stage, the influence of the ash component on the water-binding ratio was estimated, at the second stage, the issue of changing the viscosity over time was considered. Laboratory tests were carried out using adapted methods for measuring the spread of the mixture and determining the setting time. According to the results of the first stage, the regularities of changes in the viscosity of the mixture by changing the water content were obtained, and the optimal ratios of water to the binder were obtained, depending on the percentage of the ash component. According to the results of the second stage, the regularities of changes in the viscosity (from the liquid to the solid state) of the mixture over the holding time, depending on the same percentage of ash were obtained. In conclusion, the data on the optimal water-binding ratio from the conditions for the manifestation of the ash-cement mixture of texotropic properties corresponding to the classical cement mixture, without the inclusion of ash, are presented.

Heat pumps are used as alternative equipment in the arrangement of hot water treatment and heating of buildings and premises. The principle of the device and functioning of heat pumps, the processes that take place during the removal of low-potential heat are described. The features of the operation of air heat pumps at subzero temperatures are disclosed. The reasons for the low transformation coefficient of air heat pumps at negative outdoor temperature are considered. This paper describes the main existing methods for ice control of heat exchangers of air heat pumps: the method of the reverse of the refrigerant, bypass method, method of ice control with non-freezing solutions, accumulative method, method of thawing using the electrical warming up evaporator, defrosting with the help of the air flow, their advantages and disadvantages in the process at low temperatures. A promising method for removing ice from heat exchangers using mechanical vibrations is presented. The operating parameters of air heat pumps with different thawing methods are given. It examines their effectiveness when the air temperature is -25°C, a comparison of energy consumption for ice control of the outdoor unit of heat exchanger of air heat pump, presents photos of the process of removing ice from the air evaporator of heat exchanger.

The production output of dyes and pigments in chemical industry is constantly increasing. Sewage waters, which contain synthetic and organic coloring agents, produce toxic effect, which is preconditioned by their low MAC values - below 0.001 mg/dm ². The most promising method of the pigmented wastewater treatment, which allows reducing the pollutants' content to the regulated permissible amount, is the adsorption method. This work presents research findings concerning sorption purification of test water media, containing methylene blue coloring agent, by using crop farming waste - chopped sunflower (Heliánthus ánnuus) stalks - as a sorption material. It has been determined that the maximum sorption capacity of chopped sunflower stalks biomass for this coloring agent is 0.245 mmol/dm ². The processing of the received data has demonstrated that the obtained adsorption isotherm of methylene blue belongs to Type V isotherms according to classification by Brunauer-Deming-Deming-Teller (BDDT) or to the S-type, according to Giles' classification. This adsorption process is the most accurately described by the Brunauer-Emmett-Teller model (BET), based on the concept of multilayer adsorption.

The paper discusses the process of implementing the transition from a monocentric planning structure to a polycentric one on the example of Kazan. In addition, the theoretical concepts of polycentricity presented by the authors of papers were analyzed, as well as the methods of deduction, induction, classification and separation of concepts were used. Then a secondary analysis of the transition to a polycentric planning structure was carried out. For the analysis, the following materials were selected - a sociological survey on the assessment of the quality of life in cities on the website Domofond.ru, Strategy of socio-economic development of the municipal formation of Kazan until 2030, general plan of Kazan, reports on the implementation of national projects and municipal programs. The development of the Small Kazan Ring and the Big Kazan Ring in the city is an important step for the development of polycentricity of urban space in the concept of the city general plan.

Abstract.This study examines modern theoretical and methodological approaches to solving the problem of program-target organization and management of meso-competitiveness in construction as a prerequisite for effective practical implementation of transformational development according to key monitoring indicators such as productivity, organizational and technical reliability. Taking into account the inevitability of the involvement of territorial construction complexes in the reproduction processes as a meso-economic competitive territorial-reproduction construction system, the article substantiates the need to develop special program-target methods for regulating these processes. It shows the expediency of combining the competitiveness, productivity of territorial construction complexes and reproduction processes in construction by the program-target method. The adopted programs should essentially become mortgage and investment programs for long-term management of the reproduction of territorial-portfolio land and property complexes in various industries and infrastructures. The study presents the efficiency of using consortium-type structures to implement the idea of forming high-performance cluster systems in construction at regional and inter-regional levels. Mortgage and investment programs for sustainable development of residential construction should become a tool for managing the process of transformational regulation of competitiveness from its local level to the interregional and international levels with a clear system organization.

In the Russian Federation, the problem of creating a comfortable urban environment is of a national nature. The authors suggest paying attention to the courtyard in apartment block development as this area is one of the most important elements of the urban environment – a buffer space between the apartment and the city. As an important criterion for a comfortable environment is its safety, therefore, it is necessary to understand which courtyards form a sense of security in people, and which do not. The formation of a sense of security of residents is influenced by many different factors. Courtyards, having a different planning arrangement, create different conditions for the comfort of living inhabitants and the degree of use by other people. The authors propose the development of a typology of courtyard spaces based on a sense of comfort and security. As basic characteristics they propose to use: planning openness of the yard, which characterizes the degree of built perimeter of the yard, as well as the permeability of the territory, indicating the accessibility of this area for other residents and their activity. This typology will be the basis for further determining how each type affects the formation of a sense of security among residents and what measures from an architectural point of view can be applied to ensure the formation of this feeling.

An intense dust emissions occur when bulk materials are unloaded by wagons into receiving cones of coarse crushing bodies (CCB). The most reliable, but energy-intensive way to localize dust emissions is the use of local exhaust ventilation systems. For the correct calculation of the performance of the exhaust ventilation system, it is necessary to determine the flow rate of air entrained in bulk material (flow rate of ejected air), which is the main source of dust emission distribution. The volume of air carried away by bulk material is determined based on the use of the classical theory of mechanics of two -component flows. Using the methods of boundary integral equations, a mathematical motion of the air flow in the cavity of the receiving cone of the CCB has been developed. A laboratory model of the CCB receiving cone was created, where the air flow carried away by the bulk material was modelled using a smoky jet flowing out of the supply nozzle. Based on the conducted computational and field experiments, the location of the local ventilation suction and mechanical screens are selected to increase the efficiency of local exhaust ventilation and reduce the energy consumption of the aspiration system.

We have offered the methods of the operative evaluation of a breaking stress in testing strength on compression of heavy concrete of grade 400 with the use of fractal formalism. The methods are based on the setting of the relations of the values of a breaking stress and fractal measurement of concrete: 1. Areas with crushed stone prevailing (R² = 0.7224); 2. Areas with sand prevailing (R² = 0.6102); 3. Pin holes (R² = 0.6874). During fractal experimenting the indexes of breaking were increased from 391.63 to 515.13 kH in reducing fractal dimension of areas 1 from 1.866 to 1.588; areas 3 from 1.826 to 1.684 and internal quality (boundary of its elements) from 1.617 to 1.353. Increase of fractal dimension was fixed only for areas containing sand (areas 2) from 1.755 to 1.944. These results make possible to apply fractal dimension as the indicator of structural changes of concrete in the prediction of its properties. In fractal modelling the accuracy of the results depends on the option of the task way for space metric that is proved by the obtained linear model (R² = 0.9254), which describes the connection between the elements of macrostructure and strength criterion of concrete.

Such methods provide a satisfactory in practical purposes operative prediction for the values of breaking stress of concrete of grade 400 with significant reduction of time and money expenditures on full-scale testing and the application of microscopy.

The results of quantum chemical simulation by B3PW91 method in the 6-31G(d,p) basis for formation of 2,2-dimethyl-3-methoxypropanal from 5,5- dimethyl- 1,3- dioxane in the presence of proton are given. The proposed reaction scheme involves protonation of the parent molecule - formation of the oxonium ion, breaking of C-0 bond with receipt of alkoxycarbenium ion, rearrangement of the alkoxycarbenium ion by two successive 1,3-displacement or 1,5 displacement of positive charge, deprotonation of the oxycarbenium ion with formation of the reaction product. Data on the structure and energy characteristics of molecular products, ions, and transition states are obtained not only for the states characterized minimum Gibbs energy (G₂₉₈, δG₂₉₈, δG^#₂₉₈), but also for possible conformers and transitions between them. Based on the calculations, an energy diagram is drawn up in accordance with the general reaction scheme.

Comparison of the estimated activation barriers (δG^#₂₉₈) for implementation of the reaction in two stages (1,3-migrations) and one-stage 1,5-migration showed that they are comparable in size, the difference is about 2 kcal/mol. Since conversion of 5,5- dimethyl- 1,3- dioxane to 2,2-dimethyl-3-methoxypropanal is an endothermal reaction with heat absorption of 3.4 kcal/mol, it can be assumed that in real conditions transformation of ions as per the reaction coordinate will include both two-stage and one-stage conversion of alkoxycarbenium ion to the oxycarbenium ion.

Calculating air exchange according to existing methods, dilutions of all heat surpluses and other hazards are taken into account. This leads to a significant overestimation of the amount of supply air and saving unreasonable costs. To solve the problem of cost optimization, the authors propose a displacement ventilation and air conditioning system. In this case, the supply air is supplied to the lower zone, where the congregation is located. In this case, it is proposed to calculate the air exchange for the assimilation of only part of the heat surplus and other harmful substances entering only the lower zone, up to 2,5 meters high from the floor level. The rest of the hazards are displaced by convective flow and supply air to the upper zone and removed to the outside. The proposed solution to the problem allows you to optimize the cost of ventilation and air conditioning in the halls of worship of Orthodox churches.

The paper deals with the problems of historical settlements, which lead to the loss of their status and critical violations of the historical environment. The author analyzes the problems of historical settlements and their particularly vulnerable type – small formations – including social, political, economic, and scientific research. The author points out the need for complex innovative approaches that ensure not only the material restoration, but also the functional development of the historical environment, the introduction of new functions. The tools of working with the historical urban environment and its active functional inclusion in the modern discourse, models of increasing the value characteristics of urban objects, as well as the principles of implementing local potentials, which are laid in the basis of a holistic methodology, are considered. A strategy is proposed that solves the extremely acute issue of the urban significance of historical and cultural monuments on the basis of management tools and spatial planning, and tactical steps for its implementation are highlighted. The methodology obtained as a result of the study can be used as a basis for a national program aimed at developing and strengthening the social and economic role of small historical cities in the country's settlement system.

The paper analyzes the properties of rocks with a shale structure, justifies the need to apply force in the direction of the lowest strength. The list of crushing equipment used in the process of obtaining cube-shaped crushed stone is given. It is established that the existing crushing equipment is not able to take into account the specific texture of the crushed materials and this does not allow obtaining cube-shaped crushed stone from shale materials. A description of the new design of the press-roll unit, which allows obtaining cuboid crushed stone from rocks with a shale structure, is given. The press-roll unit includes a device for directional feeding of shale materials to its working bodies, which create a force effect on the fed pieces of rock in the required direction. The design of the tooth of the working body is described, which allows to reduce significantly the replacement time of worn elements and reduce the bending loads acting on it. This leads to an increase in the reliability of the structure and reduces the metal consumption of repairs. A mathematical model of the directional movement of shale materials in a roll device is considered and an equation for calculating the required force is obtained. Graphical dependences of the influence of the roller installation angle and its horizontal and vertical displacement on the amount of deformation of the feed material layer are presented.

The work presents an analytical solution to the equation of moisture permeability of structural varieties of capillary-absorbed moisture in a multiphase soil system with incomplete water saturation considering the influence of load potential. Researches were carried out and the influence of external load on the moisture profile in a multiphase system, the rate of moisture transfer of a discontinuous flow in general, and the rate of moisture propagation of the wetting boundaries have been shown. For a comparative analysis of the indicators of moisture transfer, functional relationships between the potential and pressure of the structural varieties of capillary-absorbed ground moisture are presented: capillary-gravity, proper-capillary and capillary-osmotic components of ground moisture. In the interval of incomplete water saturation, an attempt was made to create the foundations of capillary moisture transfer in the soil environment considering both the external distributed load and the own weight of the soil.

The article considered the issue of thermal stabilization of buildings, formed a mathematical model for the room. The applied systems of thermoactive structures are described, their strengths and weaknesses are determined. Other methods of "passive" cooling systems are considered, it is determined that the main air conditioning systems are not fully used is technically and economically feasible, however, as complementary systems for the off-season must be taken into account. The heat supply system using a heat pump and a low-potential source (sewage) is described. This system allows for more efficient use of the evaporative-condensation cycle by operating with a smaller temperature difference between the heat pump flow and the low potential source. It is shown that the main attention should be paid to the development of alternative heating systems and the use of renewable energy sources. A significant part of the equipment used cannot always be considered as part of the overall strategy for the formation of an ecological building. The use of forms of heating based on low-potential sources will improve the environmental performance of residential and industrial buildings.

Construction in northern conditions is complicated by the processes of seasonal freezing and thawing of soils. This factor is of particular importance in the area of permafrost distribution. The paper deals with the problems that arise when laying communication networks. Any engineering solution must be justified by a heat engineering calculation. In one case, it is necessary to exclude the thawing of water or sewer networks, in the other case – to prevent the destructive effect of the heating main on the permafrost soil. The most common mathematical model of the heat transfer process in the presence of phase transitions is the Stefan problem. When calculating the processes of freezing-thawing near the pipes of communications, it is rational to set the problem in cylindrical coordinates, using the property of plane-radial symmetry. But the Stefan problem has an exact solution only in Cartesian coordinates, for the case of plane-parallel symmetry. For this case, many approximate dependencies are also obtained. The paper presents a method that allows using the results of solving the plane-parallel Stefan problem to solve the plane-radial problem with the same values of the input parameters. Approximate values of the coordinate of the phase transition front as a function of time for the plane-parallel and plane-radial areas are obtained using the method of sequential change of stationary states. A one-to-one relationship is established between the obtained values. If there is a solution obtained by any method for a plane-parallel area, and then using this dependence, it can be applied to a plane-radial area. This technique is suitable not only for the Stefan problem, but also for many nonlinear heat conduction problems. The results given in the paper are of practical importance: using the above method, almost any solution obtained for one type of symmetry directly extends to other types of symmetry.

The paper deals with the issues of technology of grouting binders of silicate materials with the use of waste from the processing of petroleum bituminous rocks. The optimal compositions of grouting solutions with the use of waste from the processing of PBR were studied.

The stability of the samples in aggressive environments of low-and high-base calcium hydrosilicates was studied. Technological processes for the production of grouting binders based on waste from the processing of PBR were justified and developed.

Grouting compositions, characterized by high quality were developed. The positive effect of mixing and storage of the tested cement mixtures containing up to 50% of PBR waste with sulfate solutions of Na ₂SO ₄ and MgSO₄ salts on the studied technical characteristics of the grouting solution and cement stone was established.

A significant result is an improvement in the setting performance, an increase in strength without a significant deterioration in the adhesion of the cement stone to the drive pipe at a 5% salt concentration.

The research results provide recommendations for the development of weighted grouting cements using technogenic materials containing an increased amount of iron oxide.

In the introduction of this work, three types of safety systems are considered when working at height. Hazardous factors have been identified that affect the safety of the user, depending on the components of the safety systems and their resistance to high temperatures. The purpose of this work is to improve safety in hazardous sectors of industry, construction and other types of work where increased protection of PPE components from sources of elevated temperatures is required, when working with gas and electric welding, as well as the resistance of materials to sparks from mechanical power tools. In the main part of the article, a new test methodology for refractory slings for positioning and holding was introduced, tests were carried out and the method was adjusted. The experience of the fire sector was borrowed, and in particular, the method in clause 9.8 from GOST R 53268-2009 Firefighting equipment was transferred and adapted. Fire rescue belts General technical requirements. Test methods". The conclusions of adaptation and application of this method to other components of personal protective equipment are made.

The desire to create new, improved working fluids for heat and mass transfer systems in the industry is gaining momentum. Now more and more researchers are being attracted to analyze the use of nanofluids in heating systems due to their improved thermal and physical properties. Nanofluids are a new type of dispersed fluids that consist of a carrier fluid in the form of which water can act, as well as polymer solutions and organic liquids, and solid particles, which are mainly particles of chemically stable metals and their oxides. The heat transfer characteristics of modern liquids are significantly improved by the addition of nanoscale solid particles with a diameter of less than 100 nm. Such liquids can be considered as promising applications in such areas as solar collectors, heat pipes, nuclear reactors, electronic cooling systems, automobile radiators, etc. The paper (publication) describes nanofluids as new energy-efficient types of working fluids for heat transfer. The most promising developments in the field of creating nanofluids from the point of view of increasing the heat transfer coefficient are presented and analyzed. Further possible promising ways of studying nanofluids are formulated.

The presented work considers the analysis of methods and means for assessing the technical condition of charge air coolers in vehicles in operation. Metallographic studies of the fragments of samples, identified local sections of the heat exchanger, have been carried out. Various defects of the internal heat transfer surface, caused by the influence of operational factors, have been revealed. The article also touches upon the problem of imperfection of methods and means of instrumental control of the operating parameters of the heat exchange equipment of road transport. It is proposed to carry out diagnostics of the technical condition of heat exchangers at specialized stands equipped with an instrumentation and apparatus complex. The prospects of new developments in the field of diagnostic equipment for determining the operating characteristics of heat exchangers with the ability to measure the most important parameter - heat transfer are noted. An important addition, confirming the relevance of the chosen direction of research, is the substantiation of the value of the described developments not only as a tool for measuring the parameters of the state of heat exchangers, but also to solve the problem of predicting their residual resource. The results of the conducted research are presented. Using the method of physical modeling, an algorithm has been developed for diagnosing the technical condition of the charge air cooler in operation. Issues of provision with methods and means of diagnosing parameters of heat exchangers of vehicles in operation and repair are considered.

Architectural concrete has wide opportunities to be used both for exteriors and interiors in different buildings. Architectural concrete is the type of concrete which is usually not subjected to finishing, therefore higher standards are declared for its surface quality. According to normative documents, architectural concrete needs to have a uniform colour tone, texture, minimal defects and porosity of the surface. The present research demonstrates the concrete surface quality obtained in the course of varying different factors such as the presence of stabilizing admixture, granulometry of aggregates, usage of fly ash and workability of the concrete mixture. In the course of the research, the testing of raw materials and concrete in the fresh and hardened state were performed according to standard methodologies. The assessment of concrete surface quality was provided through the analysis of concrete surface photo 50x50 cm size. Based on the experimental results, it can be stated that better quality of the concrete surface was obtained in case of usage of gravel with two fractions of 4/16 and 2/8 and fly ash in the dosage of 25 % cement weight in the presence of plasticizing and stabilizing admixtures. The concrete mixture with high workability showed better filling of formwork and mixture particles packing on the formwork surface which led to a better quality of the concrete surface.

The purpose of the study contains two main aspects: - improvement of the spatial organization of the shift settlement of the oil and gas industry - the potential of the structure-forming component of the country's settlement system; - development of the optimal functional and planning structure of the morph types of the shift settlements, providing a high level of comfort that meets the increasing needs of a modern, dynamically developing society. Comprehensive review of the existing forms of spatial organization of shift settlements is carried out on the example of foreign and domestic experience in the design, construction and operation of shift settlements at various stages of development in order to identify the intensity of their formation and determine the most perspective type, as a basis for development and the subject of further research. The vector of external and internal, first of all, production -technological and social factors influencing the morphology of shift settlements and the structure of territorial settlement in the system of industrial development of the natural complex is determined. The evolutionary transformations of the morphology of shift settlements in all countries took place taking into account the factors and characteristics of natural-geographical, climatic, socio-economic aspects and functional-industrial affiliation. Considered the circumstances and features of formation of the architectural and planning organization of shift settlements that affect the creation of an algorithm of gradual development through modernization the quality of its internal spatial structure. The increasing technological potential of the territories stimulated to the formation of typological and classification diversity of the territorial structure and spatial organization of shift settlements, their morphological and taxonomic hierarchy. On the basis of a concept formulated a predictive theoretical model of the holistic shift space settlements, with the functional program of the formation of the quality of the environment is comparable to quality of life in large urbanized space with respect to information-technology resource of the modern world, shaping the potential for sustainable development.

Using the methods of thermal gravimetric analysis, and X-ray phase analysis, the puzzolan activity of the natural zeolite tuff of the Lyulinsky deposit of Khanty-Mansiysk Autonomous District -Yugra as a mineral additive to cement was evaluated. Acid modification of natural zeolite tuff was performed. The selection of modification conditions was carried out by varying the concentration of the acid solution, the time of exposure to the reagent, and the temperature. The optimal parameters were: the concentration of hydrochloric acid 3 M, the duration of acid exposure-5 hours, the temperature of 80°C. It was found that the treatment of tuff with 3M hydrochloric acid solution leads to a significant increase in puzzolan activity. The strengthening effect of the modified additive is shown. The strength of cement samples with the addition of zeolite tuff at a similar age increases by 28%. The effect of the addition of zeolite tuff on the phase composition of cement during hydration and hardening is studied. A more significant decrease in the content of portlandite was recorded when using a modified additive compared to the addition of zeolite tuff in its native state, which is consistent with the data obtained from the mass loss curves. At the same time, an increase in the content of ettringite, which contributes to the strengthening of the structure of the binder part of the cement stone, is shown. The degree of hydration of cement was estimated by the change in the content of alite. A complexometric determination of the aluminum content in the washing waters after acid treatment of zeolite tuff was carried out. It is shown that acid treatment leads to its dealuminization, which is associated with the restructuring of the zeolite framework. This, in turn, provides an increase in the number of active acid centers responsible for its adsorption properties and reactivity on the surface of the aluminum-silicate framework of the zeolite.

The results of experimental studies of the coagulation treatment of the Sura River water in the autumn period and during high water with the use of mixed coagulants based on aluminum sulfate (AS), polyaluminum chloride "AQUA-AURAT 18" (PACl) and organic coagulant FL 4540 are presented. When treating river water with a low temperature, the use of mixed organic and mineral coagulants allows for a more significant reduction in the turbidity of the settled water compared to mineral coagulants AS and PACl at the same doses. Mixed coagulants with a weight ratio of FL 4540: AS (or FL 4540: PACl) equal to 1:4 have a greater efficiency of action compared to coagulants with a ratio of organic and mineral parts equal to 1:1. When treating low-turbidity water with a low temperature in the autumn period, the highest effect of clarification by settling was obtained using mixed coagulants based on PACl and FL 4540. At a standard mixing time of the initial river water with coagulants of 2 min, the use of a mixed coagulant K3 based on PACl and FL 4540 allows getting the same lightening effect as when using only PACl, but with doses lower by 30%. Experimental data on the coagulation treatment of the source water with low alkalinity and increased turbidity during the flood showed the greatest effectiveness of the mixed coagulant K1 based on AS and FL 4540, the use of which, with a mixing time of 2 minutes with the source water, reduces the dose of AS by 10% with the same settling effect. Increasing the mixing time with water to 15 minutes increases the effectiveness of the mixed coagulants, which in this case can reduce the doses of AS and PACl by 1.6-2 times without compromising the quality of clarified water by settling.

Seamless pipes are mainly used in the oil, gas and defense industry, what places special demands on its reliability and safety. It is very important to select the steel grade and heat treat the mandrels for flashing and cross rolling of seamless pipes in order to ensure the required operational characteristics. The work is devoted to the substantiation of the choice of 4Kh5MF1S steel and the development of the technological cycle of manufacturing mandrels of increased strength for sheet and transverse-spiral rolling of seamless pipes. The optimal combination of strength and ductility of this steel during heat treatment was established, which includes quenching at 1070 ° C and tempering in the temperature range of 650-700 ° C. Based on the analysis of the structure and mechanical characteristics, an optimal mode of heat treatment of steel 4Kh5MF1S was proposed: quenching from 1070 °C in oil and tempering for 2 hours at the temperature of 650-700 °C, which makes it possible to recommend it for use as a heat-resistant structural material for highly loaded metal products with the yield stress o0.2 from 750 to 1000 MPa.

In this article, the author raises the problem of assessing the residual resource of an object, which consists of several buildings and structures. Four different approaches to solving this problem are presented. The advantages and disadvantages of these approaches are presented. The areas of their application are indicated. Within the framework of these approaches, one can use the direct enumeration method, the combinatorial method, the algebra of logic, the general logical-probabilistic method. The author has developed two possible options for calculating the residual resource of these objects using the general logical-probabilistic method. It is proposed to develop a Methodology for calculating the residual life of such objects before the survey. The author indicates the main points that must be prescribed in the developed Methodology. An example of calculating an object consisting of five buildings is given. The scheme of functional integrity is constructed according to the general logical-probabilistic method. In the program complex "Arbiter" the static and probabilistic-time calculation of the given scheme is performed. Then the calculation of the object as a whole was carried out according to the "2 of 5" system. As a result, the value of the probability of failure-free operation and the residual resource of the object as a whole is shown.

The paper presents studies on the use of ash of hydraulic removal in combination with modifier additives in the production of non-autoclaved foam concrete. The research is aimed at obtaining high-quality non-autoclaved foam concrete based on industrial waste with high construction and technical properties. The main objective of the paper is to determine the quality indicators of non-autoclaved foam concrete, according to standard methods, corresponding to the normative and technical documentation. The studies were carried out under laboratory conditions on certified and calibrated test equipment. The industrial waste considered in the paper, the ash of hydraulic removal and food industry waste, are common waste in all countries of the world, which gives high relevance to the research topic within the framework of waste disposal. The conducted studies confirmed the effectiveness of the integrated use of waste, to obtain the best result. As it is known, ash reduces the thermal conductivity, which is a positive effect, but at the same time reduces the strength of the material and frost resistance. In the paper it was proved that with the use of oil processing waste, it is possible to obtain an increase in frost resistance due to volumetric hydrophobization, as well as with the use of alcohol production waste, a significant increase in strength is achieved, due to the plasticizing effect of the casein contained (polymer components) in the composition of alcohol production waste. The obtained results of the study on thermal conductivity, strength and frost resistance confirm the effectiveness of the use of ash in combination with modified additives based on food industry waste CM-2 and CMA-P. In conclusion, a comparative analysis of the effectiveness of the use of industry waste the ash of hydraulic removal in combination with modified CM-2 and CMA-P additives is carried out.

The article is devoted to analysis and systematization of classical wooden buildings in Tomsk. The relevance of the work is due to the problems of preserving the valuable of Tomsk historical and architectural heritage and this topic is poorly known . Wooden buildings in the classicism style were widely spread in the nineteenth century. They were classified as a residential development and were subjected to reconstruction and demolition in the Soviet period. Currently the wooden classical buildings are the most ancient and already quite rare and therefore it is necessary to conduct the research on its identification, study and systematization.

The novelty of the study is to conduct a comprehensive analysis and identify the typology of wooden buildings in the classicism style of Tomsk. In the course of the work the authors used the following methods: critical analysis of bibliographic sources, comparative architectural analysis and system-structural analysis of information, as well as creative synthesis in the formation of conclusions.

As a result of the conducted bibliographic and field studies the identified objects were divided into four main types according to their volume and spatial characteristics. It is established that the classic wooden building in Tomsk has great historical value. It is the material embodiment of constructive and technical knowledge, architectural and artistic traditions.

Due to the expansion of St. Petersburg from the beginning of the 20th century, the city has formed a Gray Belt of unexploited factories, some of which are architectural heritage. The modern solution to the problem of the Gray Belt is the creation of lofts and public spaces from them, however, it is also practiced transforming former factories into a site for generating "green energy". Because of the finiteness of the extracted minerals, the use of renewable resources is the most favourable way of producing electricity. The purpose of this work is to consider the possibility of using an industrial pipe to generate energy on the example: one of the highest unexploited pipes in Grey Belt - a steamshop's chimney (100m), built-in 1955. The result of the study is to determine the inexpediency of using the principle of a wind tube in chimneys in the Gray belt in St.Petersburg, because, based on the calculations, according to the developed method, the height required for the wind turbine to start moving is 154 m in the summertime in St. Petersburg. During the consideration of the highest pipe in the Leningrad Region (320m), there was concluded that it can provide electricity for 31 people.

In the introduction of this work, the problem of the lack of test methods for personal protective equipment against falls from a height (hereinafter PPE), used in the areas associated with direct contact of PPE components with sources of elevated temperatures, is disclosed. The experience of the fire sector was adopted with fire tests for the impact of materials used in the production of PPE products in contact with an open flame. A number of tests were carried out on refractory slings for holding and positioning and the results obtained with a positive approbation of the method. The purpose of this work is to improving overall safety when working at height, to identify weak zones of protection of components of safety systems from various external factors that negatively affect them. Work was carried out and conclusions have been drawn about the application of this method on refractory slings for holding and positioning. One of the important requirements of customers of these slings in production is the resistance of materials of safety systems to the interaction of components in an environment of high temperatures. The conclusion of this work is the relevance of the application of this technique to the PPE sector, in particular to refractory slings for holding and positioning.

The article deals with the study of the compositions of corrosion-resistant concrete. They can be successfully used to prevent the destruction of structures in linen processing plants. Such plants include single workshops with an aggressive environment. Keeping retted stalks in compositions that are aggressive for structures is reflected in the condition of reinforced concrete and concrete structures of these workshops. Violation of the integrity of such structures can lead to severe environmental consequences. To eliminate such consequences, it is necessary to carry out reconstruction. Repair and reconstruction of structures must be organized through the use of innovative concrete. Such concretes must have a high density and resistance to corrosion. Analysis of information sources showed the effectiveness of using ashes with a high content of aluminosilicates. The work identified factors that determine the strength and density of concrete with the addition of ash. Based on the results of the work, recommendations were formed on the use of plasticizers. The composition of the organo-mineral complex has been developed.

In various industries, there are often technological processes that are characterized by the release of dust into the working area. This dust is the cause of various diseases of the workers of the enterprise. To maintain the required air parameters in terms of the dust factor in industrial premises, it is necessary to use a complex of systems, including an aspiration system, a centralized vacuum dust removal system and general ventilation. Each of the listed systems will fulfill its specific task, but their efficiency and productivity are interrelated. There are numerous works that consider the operation of systems separately, however, the final concentration of dust in the room, in the end, will depend on their simultaneous operation. The article presents a developed method for calculating the efficiency of a complex of dedusting systems, which will allow at the design stage to assess the concentration of dust in the air of industrial premises and, if necessary, make the necessary adjustments.

The paper deals with the choice of the algorithm for processing the data of the load sensor of the crane weight measuring system being developed. The requirements for the weight measuring system are based on the operating conditions of the crane (the nature of the dynamic process, the limitation of the weighing time) and the planned use of information about the weight of goods (the required accuracy). A comparison of 5 signal processing algorithms is presented: direct averaging, search for extremes with two different modes of pre-smoothing, nonlinear regression, and averaging using a short-term memory buffer. A series of experiments was conducted to compare the methods. The data was obtained on the KMG-201 bridge crane. Based on the results of numerical evaluation of the results of experimental data processing, conclusions are drawn about the applicability of the considered algorithms for analyzing the dynamic process of the crane lifting mechanism. The algorithms for finding extremes, regardless of the pre-smoothing modes, did not show the required accuracy (the relative error was 5%). The averaging algorithm using a short-term memory buffer showed the highest accuracy (the relative error was 1%). The influence of the parameters of the data reception board on the result of the algorithms is estimated. The parameters varied in the range: bit depth 10-12 bits, sensor polling frequency 4.1-256 Hz. Most experiments showed an increase in accuracy with increasing bit depth. Also, according to the results of the experiments, it was found that an increase in the sensor polling frequency of more than 64 Hz in the conditions of this dynamic process does not affect the accuracy of determining the weight of the load. The study showed the need for further work in the direction of determining the optimal parameters of the averaging algorithm with a short-term memory buffer and determining the limit of increasing accuracy with increasing the bit depth of the data reception board.

The production of building materials uses large amounts of primary natural resources. Mineral and organic components of the natural environment are used as raw materials, which leads to degradation and disruption of the habitat of living organisms. One of the possible methods to reduce the consumption of natural resources is the use of industrial and consumer wastes as raw materials, which include polymer waste. The high resource potential of polymer waste as a fuel is shown. Waste can replace coal coke, which is used in ferrous metallurgy technologies. The analysis of several technologies for the use of polymer waste as an inert filler and as a bituminous binder in the production of asphalt concrete and building mixtures has been carried out. The classification of various groups of polymer waste by melting temperature and chemical composition is presented. The analysis of technological processes for the use of polymer waste made it possible to conclude that considerable attention is paid to the extraction of economic benefits without environmental assessment of the safety of the technologies used. An environmental assessment of polymer waste disposal technologies has been proposed, which will allow at the stage of technology development to assess the environmental risks arising from the production and operation of the resulting product. It is proposed to select the temperature range in the technological processes for obtaining secondary products as indicators of the formation of environmental risks when using polymer waste.

One of the areas of work on the technology of producing products based on titanium hydride fraction HTK-D is the study of methods and modes of modifying the surface of titanium hydride fraction in order to increase its thermal stability at high temperatures and protect titanium from oxidation. The research was carried out using modern instrumental physical methods and physical and chemical analyses. Differential thermal and thermogravimetric analyses of the initial and modified titanium hydride fractions were performed in the temperature range of 20-1000 °C in the air atmosphere. The curves TG and DTG of the initial fraction of titanium hydride show a slight change in mass in the temperature range of 20-100 °C with a maximum at T– 82 °C, which is associated with the removal of sorbed moisture. The data of the DTG analysis showed that the modification of the titanium hydride fraction with sodium borosilicate leads to a noticeable decrease in the mass loss of the samples: in the temperature range of 600-900 °C, the mass loss for the modified titanium hydride fraction was 0.39 and 1.58% (wt.) for the initial fraction of titanium hydride. In the course of the experiment, it was revealed that a further increase in the temperature leads to an increase in the mass of titanium hydride fraction samples, which is a consequence of titanium oxidation. It was found that the modification of the titanium hydride fraction with sodium borosilicate increases its thermal stability.

The paper is devoted to investigation of S235J2 steel quality criteria variation during thirty years' service life as a part of construction of power-generation unit #1 of Zaporizhia Nuclear Power Plant (NPP). The microstructure of the steel has been evaluated by fractal methods. Fractal size of the steel structure has higher correlation to mechanical properties of the steel compared to microstructure analysis. During service life of the steel YTS ranging 10.01% (24.9 MPa), UTS ranging 9.42% (39.5 MPa), while elongation ranging 43.16% and Reduction of area ranging 39.58%. These values can be explained by strain ageing of the S235J2 steel during service life. It has been stated that fractal size of pearlite and strength have good correspondence (YTS has fractal model correlation coefficient R² = 0.6194, while UTS has R² = 0.8068). The correspondence of ferrite fractal size to ductility has been calculated (Elongation has fractal model correlation coefficient R² = 0.6493 and Reduction of area has R² = 0.5258). Analysis of the S235J2 quality criteria fractal models let the range quality criteria depends on fractal size of the ferrite-pearlite structure of the steel. Experimental results prove the possibility of usage the fractal models for predicting remaining life of the steel constructions at NPP. Therefore, the fractal modelling may be assumed as a promising nondestructive test method for NPP.

The paper deals with the issues of technology of binding silicate materials with the use of mineral waste from the processing of petroleum bituminous rocks (PBR) – optimization of the ratio of raw components of the mixture of binders, development of optimal technological parameters for their production.

The optimal compositions of binders were studied using waste from the processing of PBR as an activating component of cement. The influence of mechanic and chemical activation on the change in the acid-base parameters of the suspension from the crushed material was revealed. The effect of the content of additives on the degree of hydration was studied. The influence of the hardening conditions on the strength of the binder with additives of waste from the processing of PBR was studied. As a result of the experimental work carried out, technological processes for the production of binders based on waste from the processing of PBR were justified and developed. The optimal ratio of the mixture of waste from the processing of PBR with cement and the technological parameters that allow ensuring the optimal grade of the cement-sand binder are found. Silicate materials based on it have high physical and mechanical properties, meet regulatory requirements and have high resistance under operating conditions.

For the first time, the authors of the article publish the results of a comparative study of unique historical and architectural monuments of Voronezh built in the period of classicism, their compositional, decorative, and space-planning features, similarities and differences as compared to the architectural prototypes of Russian capitals, and their correspondence to the "model" projects of the late 18^th and early 19^th centuries. The results of the architectural-decorative, structural-compositional, morphological, and factor analysis, based on the most outstanding examples of Voronezh architecture of the first half of the 19^th century, can enhance the understanding and deepen the scientific knowledge on the origins of the development of the classicist tradition in the provincial architecture of Voronezh. A correlation was found between Moscow buildings of the school of M. F. Kazakov and his contemporaries, as models and prototypes, and the classical architectural monuments of Voronezh. The prototypes of "model" projects designed by the architect V. P. Stasov, which completely correspond to the Voronezh buildings of the first half of the 19^th century, were established. The determination of architectural analogues and models of classical Russian architecture, which have become the prototypes of provincial Voronezh architecture, based on the regulation and state control of the construction will significantly expand the attribution of historical and architectural monuments of classicism in Voronezh as an integral part of all-Russian architecture.

The heating system is one of the life support systems. The discrepancy between the thermal (temperature) conditions of the living quarters is one of the most urgent complaints of residents of apartment blocks in most regions of the Russian Federation. The object of the study is a single-pipe water heating system of a 14-storey apartment block with an overhead distribution, for which the heat output is determined to compensate for heat losses under various initial conditions (outdoor air temperature and infiltration airflow rate). As a result of the calculation of the thermal conditions, deviations in the indoor air temperature of living quarters from the permissible range are determined. To eliminate violations of the microclimate parameters, this paper considers ways to increase the heat transfer of heating appliances by increasing the area of the heating appliance, as well as increasing the flow rate of the heat-transfer agent passing through the appliance. The results of the calculation of the thermal conditions showed the impossibility of eliminating the violation of the thermal conditions by these methods: depending on the temperature of the outdoor air in the living quarters, there is an excess or lack of heat. To eliminate the thermal and hydraulic disarrangement, a mechanical method for adjusting the heat transfer is proposed by switching off the sections of the heating appliance with an increased number of them. Taking into account the recommendations on the need to ensure that the length of the radiator corresponds to 50-70% of the length of the window opening, this method is functional for use.

Information on the kinetics of aging of coatings is presented.The process of moistening was considered as one of the particular cases of aging. During incubation period there is a slight increase, and possibly a decrease in defectiveness. The duration of the incubation period is 0.2 -0.5 of the entire durability.The active stage of damage accumulation begins after the incubation period. In the active stage of accumulation of damages, significant changes occur in the structure and properties of the coating (change in color, shine , cracking, etc.).Determined that the beginning of the active stage of accumulation of lesions coincides in time with the first significant changes in the surface area of the coating. It was found that there is a correlation between the experimental data on the kinetics of damage accumulation, the degree of chalking, and surface area. It lies in the fact that the active stage of damage accumulation coincides with the beginning of chalking of coatings. An analytical dependence is proposed that makes it possible to estimate the area of the defective surface of the coating during aging. The dependence of the level of damage accumulation on the duration of tests can be described by a logistic curve (or Pearl curve)

When designing the organization of construction by the flow method, the presence of unbalanced non-rhythmic flows is inevitable. The article deals with the issues of balancing non-rhythmic construction flows at a slow pace on the basis of a matrix algorithm for calculating the parameters of the construction flow. Methods of balancing construction flows are described. The matrix calculation of the parameters of the non-rhythmic flow balanced at a slow rate showed the properties of potential and paradoxical works. From the calculation results it is seen that increasing the rhythm accelerated processes on the allowed organizational downtime between jobs on the hook improves the quality of the construction of the flow, namely increasing the density ratio of the graph, reducing the total amount of organizational downtime, improve utilization of the scope of work. The total duration of the construction flow remains the same when using the properties of potential works and decreases when using paradoxical works.

The work was aimed at developing a gypsum dry construction mixture with highly dispersed fillers based on industrial waste for interior decoration. The problem of creating effective gypsum materials was solved by improving the structural, physical and mechanical properties of gypsum stone by modifying it with highly dispersed fillers. The effect was achieved by creating a multicomponent composition based on hemihydrate plaster. The proposed work is aimed at developing a gypsum dry construction mixture with highly dispersed fillers for interior decoration of buildings. Dry construction mixes based on gypsum binder are one of the most relevant materials on the building supplies market. They meet the most important aspects from the standpoint of efficiency and safety - environmental, fire and others. However, the problem of ensuring high performance properties requires a solution. In this work, the problem is solved by improving the structural, physical and mechanical properties of gypsum stone by modifying it with highly dispersed fillers. The effect was achieved by creating a multicomponent composition based on plaster. Additionally, the problem of environmental protection is being solved, since secondary products were used as fillers - waste from the production of basalt products and thermal power plants. They differ in the required grain and chemical composition. Acid ash was used. Basalt and acid ash particles have a mechanical effect on the structure of the gypsum stone and influence the processes of structure formation of the gypsum stone. They change the morphology of gypsum crystals. This improves the mechanical strength, the average density of the modified gypsum stone and other physical and mechanical characteristics.

The results of physico-chemical studies that allow us to judge the changes occurring in the cement stone under the influence of liquid chloride-containing media are analysed. Samples of CEM I 42,5N Portland cement with a water-cement ratio of W/C = 0,3 were exposed to solutions of 2 % MgCl ₂, 0,001 % HCl and 0,1 % CaCl ₂ for 150 days. Changes in the strength characteristics of CEM I 42,5N Portland cement samples under the influence of chloride-containing media were studied. It is established that the 2 % MgCl ₂ solution is an extremely aggressive medium in the conditions of liquid corrosion of concrete, its action causes a deterioration in the strength characteristics of concrete by 1,5 times. The changes in the structural and phase composition of concrete that occur under the influence of chloride-containing media are studied. The relationship between the characteristics of the cement stone structure and the strength parameters of the cement stone is established. The decrease in the strength of cement concrete is associated with the decomposition of calcium hydrosilicate C ₂SH under the influence of liquid aggressive chloride-containing media, as evidenced by the decrease in intensity and the disappearance of the lines corresponding to this compound on X-ray images.

In Yakutia, there is a tendency to build individual houses in rural areas. Due to the complex geographical location, economic problems and transport and logistics difficulties, it is not possible to connect many settlements to centralized sources of energy supply. Therefore, the demand for efficient autonomous sources of thermal generation due to the use of local solid fuels has recently increased. Practice shows that heat generators of imported and national manufacturers are not adapted to work at low outdoor temperatures. In the climatic conditions of the North-East of Russia, one of the important tasks is to increase the reliability and efficiency of heat generation sources; this is a necessary condition for ensuring comfortable working and living conditions for a person.

The construction of highways requires a large amount of building materials. Organo-mineral mixtures, which include asphalt concrete, are the main building material for the construction of the upper layers of the road structure. In order to reduce the cost of asphalt concrete, part of the natural mineral raw materials may be replaced by industrial waste. Previous studies show that waste from various industries in terms of their physical and mechanical properties are not inferior to natural raw materials used in road construction. When using the material resource of waste, environmental issues are additionally resolved by reducing the volume of waste disposal at landfills. The studies carried out have shown that the composition of the asphalt concrete mixture, in which drill cuttings are used, as a mineral powder, meet the requirements for asphalt concrete. Studies have shown that waste plastics HDPE and LDPE can be considered as reinforcing and modifying elements in the structure of asphalt concrete. Asphalt concrete, which includes plastic waste, meets the requirements for asphalt concrete used for road construction.

Nowadays, the process of calculating structures is more and more entrusted to automatic calculation systems or artificial intelligence. This increases the accuracy and reliability of the calculations, but does not contribute to the understanding of the real work of the structures by the design engineer or architect. The main difficulty in carrying out such calculations is associated with the multifactorial nature of the solutions, and, as a rule, a significant number of unknowns and variables included in the calculation. The calculation is always carried out with the introduction of a certain degree of accuracy, which, in combination with a large number of variables, leads to the appearance of the effect of a cumulative decrease in the degree of reliability of the calculations carried out and the accumulation of statistical error. In turn, this can develop into a critical state. The technique presented in the article allows one to reduce the number of variables when solving problems of calculating statically indeterminate structures without changing the final result of the calculation.

The paper considers the results of the application of photogrammetry to assess the deformations of rod and plate elements of the steel constructions of hoisting machines, the analysis of the main problems arising in their processing and the proposed solutions to ensure the necessary accuracy. The authors, based on their own research and practical experiences application in the use of photogrammetry, carried out accuracy rating the magnitude of deformations. Based on a brief review of normative documents, proposals for rationing the permissible values of measurement errors are given. The paper also considers the problems that may arise in the assessment of the deformed state of design status and proposes approaches to solving these problems. One of the problems solved in the study was to assess the magnitude of the deformation of the rear belt of support of blocks of equalizing polyspast, resulting from an emergency situation during the operation of the crane KPL-16-30. In addition to assessing the overall deformed state of the entire element, the deformation in some sections of the structure was assessed. The application of some approaches to estimating the deformation of rod structure elements based on modeling the shape of the a curved axis of a beam or rod. Also considered the experience of deflection measurement the deflection of the 0.5 t electric hoists guide in the laboratory of hoisting machines. The authors shared their inspecting of the wagon tippler No. 2 examination. In addition to the assessment of transverse deformations, the task was to check the possible torsion of the metal structure of the moving part. In the process of work some problems were also revealed, the solution of which will make it possible to provide the necessary accuracy of measurements. When evaluating the approximation accuracy, the authors propose to use several approaches.

This paper presents a practical application of the improved method for calculating of slab foundations designed in karst rock areas. The method implementation is associated with the application of the updated analytical model taking into account behavior patterns of the ground base in the karst hole zone. The analytical solution obtained in the closed-form in the nonlinear formulation, allowed to obtain two key parameters of the foundation bed in the zone being studied - ? and ?_???. The dependence to determine the size of the weakening zone around the karst sinkhole area - ? and the developed criterion for the quantitative change of the coefficient of subgrade reaction ?_??? in the zone of this weakening made it possible to propose a bilinear model of the interaction of the "foundation slab - base" system. The parameters of the base weakening obtained as a result of the problem solution have a wide range of changes depending on the physical and mechanical characteristics of the base soils and can be used for engineering calculations of slab foundations designed in karst areas. The comparative analysis of the calculations made according to the proposed and normative methods showed a substantial under-reinforcement of the foundation slab projected in the karst-hazardous zone.

Abstract The paper substantiates possibility and necessity of applying the system stability theory to the management of a construction project. Stability theories of automatic control systems are considered. Sustainability of construction projects is considered based on the sustainability theory of organizational systems. The indicators that characterize the degree of stability of the construction project are determined.

The main indicators of project sustainability are Net Present Income, project payback period, internal rate of return and project profitability. A mechanism for calculating these indicators before and after the application of the project management technology is presented. Approbation of the proposed project management technology based on sustainability indicators was carried out on the example of the construction of the "Villa Rose" cottage village. In the process of management, risks were identified at the stages of project implementation with the help of independent experts. The integral indicator of the project risk has been determined and the project risk management strategies have been selected.

The article deals with issues related to the peculiarities of the formation and change in time of the stress-strain state of rock massifs as objects of active man-caused impact of engineering facilities, both surface and subsurface, hydrotechnical and road construction, mining operations, including development of mineral deposits by open-cut and underground methods. Arrays of rock formations have a wide range of properties that manifest themselves as hazardous natural geological events, and also under any technological influences to them, including the method of blasting destruction. The peculiarities of the behavior of such arrays consist in the combination of the characteristics of solid as elastic and plastic bodies, including brittle, and viscous-flowing bodies, and creep.

Technological impact on the rock mass can lead to undesirable dangerous consequences both from the point of view of the object's stability and safety, and the need for additional material costs to maintain the equilibrium in the new conditions. The identification of the potential area of permissible deformations and the conditions for the destruction of such an array of rocks, taking into account the time factor, is of practical interest for selecting effective parameters of mining technology that allow the prevention of dangerous undesirable consequences of destruction.

The problem of seismic activity and carrying out anti-seismic measures is extremely urgent at the present time. A large number of regions are more or less earthquake-prone and sometimes new regions, in which seismic activity has not been recorded before, fall into this category. Various methods of seismic load reduction are used to build new structures and support existing structures in these areas. The seismic load is transmitted to the structure through the foundation, therefore one of the effective ways to reduce it is to change the properties of the foundation. If instead of soil, which perfectly transmits impulses of seismic load, fill in a certain order with material that dampens these impulses - the desired effect can be achieved. The article analyzes the way of how one-dimensional pulse becomes attenuated in a multilayer rod. The layers in the rod are arranged in a periodical order and have contrasting acoustic properties. Numerical analysis is carried out using the finite element method. A pulse hitting the interface between the media undergoes multiple reflection and refraction, which causes damping in a purely mechanical system. The analysis shows that the larger the difference in acoustic properties between adjacent layers, the higher the attenuation of acoustical properties becomes.

It is proposed to distinguish the false setting from the abnormal one, considering the false as a variety of the latter. With false setting, the start of setting occurs in a short time, but then it spontaneously disappears, reappearing after a while. Such cements, in which the beginning of setting occurs faster than 50 minutes, and the end – after 5-12 hours, are proposed to be called abnormal cements. It is shown that when the start time of setting is more than 50 ∼ 60 minutes, the probability of abnormal setting decreases sharply. The kinetics of structure formation of cements with different setting patterns is considered. Methods for the identification of abnormal setting by the setting interval (τ_final – τ_start)/τ_start > 3, the kinetics of structure formation, heat release, and changes in the activity of calcium ions in the liquid phase of cement paste of normal density are proposed. It is shown that the measurement of the kinetics of heat release and the activity of Ca ²⁺ ions in the liquid phase of cement paste is of great interest for the development of automated and rapid control of the presence of anomalies during setting. It is established that the mixture of the inhibitor and the booster of the setting acts according to the rule of additivity, the use of mineral additives of acidic composition weakens the abnormal properties of cement systems. To combat the belated anomaly, it is necessary to monitor the properties of the cement 1-2 days before its application.

The results of the survey and calculation of the stability of retaining walls along highways located near the incline of the slope are presented. The analysis of the results of the numerical solution for modeling the interaction of the slope and the retaining wall shows that the most dangerous areas are the zones of development of maximum horizontal deformations at the retaining walls due to shear deformations. The zone, where shear deformations are spread, covers a large volume of slope soils. Collapsing soils, sinking from their own weight on the slope during water saturation, worsen the initial value of the adhesion, the angle of internal friction, the modulus of deformation, changing the stress-strain state. The trajectories of the movement of particles of collapsing soil when the stress-strain state of the slope on the retaining wall changes show that the movement of soil particles occurs at the boundary of collapsing and non-collapsing loams. Numerical calculations carried out under the PLAXIS program showed that in the water-saturated state, the slope is a landslide. The retaining wall on the incline of the slope, made of collapsing soils, is not stable and the sliding of the soil occurs only in the layers of collapsing soils of the slope.

Management of the pore volume and the mineral-morphological state of the hardening system through the use of chemical and mineral additives introduced both separately and in complexes is considered to be one of the defining directions of cement system structure formation. Currently, the nomenclature of mineral modifiers includes a wide list of materials of natural, artificial, and technogenic origin. The purpose of this study was to establish the influence regularities of mineral additives of various compositions (siliceous (microsilica, diatomite, opoka), aluminosilicate (metakaolin, fly ash), sulfoaluminate (expanding sulfoaluminate modifier), carbonate (microcalcite)) on the physical-mechanical properties of cement systems, with the identification of the most effective modifiers. According to the results of experimental studies, the influence of modifiers on the activity of the mixed cement binder, water demand, water-holding capacity and mobility of the cement paste was revealed. Condensed non-compacted microsilica, metakaolin and expanding sulfoaluminate modifier were selected as the most promising mineral additives.

The main fundamental difference of wave gears from all other meshing gears is the presence of a flexspline which is implemented in the form of a shell structure, and which, by means of a wave generator located on the input shaft, modifies the rotational motion of the wave generator into permanent elastic wave deformations of the flexspline, which are then transformed in the rotation of the output shaft. The design features of harmonic gear drives provide them with a number of significant advantages, such as smaller dimensions and weight, in comparison with conventional ones, including planetary gear train of the same torque. They have the highest kinematic accuracy, including damping behavior and low level of noise and vibration. A unique feature of harmonic gear drives is the ability to transfer rotation into a sealed space with almost zero fluid leakage. Harmonic gear drives are capable of carrying out large gear ratios in one stage: for steel flexspline, from a minimum of about 60 to a maximum of 300. At the same time, their efficiency is quite high - in the reduction mode of 80 ... 90 %, as in planetary gears with the same gear ratio. When operating in the torque multiplication mode, the efficiency noticeably declines. The disadvantage of harmonic gear drives is a relatively low frequency of the wave generator rotation, approximately within the range of 1500 ... 3500 min ¹ with the radii of small flexspline from 125 to 25 mm, respectively. Therefore, the power of harmonic gear drives, despite the high transmitted torques, is limited to relatively small values - from 0.1 to 48 kW. Their service life is limited to approximately 10⁴ hours; a year and a half with continuous operation throughout the day. Specific weight and cost of harmonic drives is 1.5 +2 times lower than those of planetary type, which represents technical and economic advantages and commercial interest for road and construction machinery.

The heat supply of most Russian cities is provided by centralized sources of thermal energy. During the operation of buildings, the transition period of the year is not given due attention. The transition periods of the year (before and after the heating season) complicate the task of providing thermal comfort in the rooms of residential and community buildings. The paper deals with the problem of microclimate troubles in multistorey residential buildings during transition periods. The purpose of this work is to test the hypothesis that there is a dependency of the temperature of the beginning of the heating season, depending on its energy efficiency class. For the thermal conditions of the rooms, the classical dependences of the thermal balance, technical thermodynamics and the theory of heat and mass transfer are used. On the example of a nine-storey apartment block, a calculation was carried out, as a result of which the rational temperature of the beginning of the heating season for various energy efficiency classes was determined, as well as the internal air temperature at the outdoor air temperature equal to 8°C (the existing value of the temperature of the beginning and end of the heating season). The results obtained confirm the hypothesis of the study that there is a dependency of the rational temperature of the beginning of the heating season for a particular building, depending on its energy efficiency class. At the temperature of the beginning of the heating season, the internal air temperature of 20°C will be achievable with a deviation of -41.182%, which corresponds to energy efficiency class A (excluding heat gain from solar radiation). It is established that at the current temperature of the beginning of the heating season, the internal air temperature of 20°C will be achievable with a deviation of -41.182%, which corresponds to energy efficiency class A, for buildings of a lower class, the temperature of the beginning of the heating season is not optimal.

The paper examines the problem associated with the reconstruction of residential buildings and the renovation of the territory of residential development of the first mass series. The issues of the current state of the five-storey housing stock in the regions of Russia are highlighted. On the example of the city of Volgograd, an architectural and spatial assessment of the development of residential development of the city is given. Attention is focused on the issues of building blocks and neighborhoods with five-story houses of the first standard series. The socio-economic, architectural and planning parameters of residential sections and apartments are analyzed in detail. Structural and planning deficiencies affecting the level of comfort of the housing stock are identified. During the discussion, the search for possible solutions related to the renovation and improvement of a five-storey residential development is shown. The evaluation of the operational qualities of the experimental construction allowed determining the complex methodological basis of possible reconstructive measures, combined in three main technological directions: renovation of the territory of a five-storey housing stock by demolishing individual buildings or entire blocks; renovation, which is based on major repairs of the housing stock without interfering with the architectural and structural system of a five-stored building; renovation aimed at changing the architectural and planning structure of residential buildings by adding additional volumes. The ways of implementation of technological directions of reconstruction of five-storey buildings that increase their compliance with the requirements of sustainability are considered.

The article discusses the characteristics of diesel generator sets currently used in autonomous power supply systems. The modes of operation of synchronous generators and their overload capacity are analyzed. The overloading capacity of diesel generator sets (DGS) can be significantly increased when used as an electromechanical energy converter of asynchronous generators (AG). The initial algorithm for their selection involves calculating the optimal value of the rotor speed and choosing the range of rotation frequency. The value of the optimal value of the rotational speed is determined depending on the method of maintaining the constancy of the current frequency when calculating the parameters of an autonomous asynchronous semiconductor cascade, which is understood as an AG together with its excitation and control system. The dependences of individual terms of electrical power losses on the operating mode of an autonomous asynchronous semiconductor stage are considered. After determining the optimal speed, the possible AG power is selected. Then, from a number of powers, its nominal power is selected. After determining the rated power, the minimum and maximum values of the rotational speed, it is possible to determine the optimal operating modes of the diesel generator set with the AG. As a criterion of optimality, the specific effective fuel consumption of the diesel generator set is taken. This approach to the choice of the type of diesel generator set when designing autonomous power supply systems requires a detailed consideration of the technical and economic characteristics of the units. The proposed design principles can ensure the most complete use of the positive properties of a diesel engine and an electromechanical energy conversion system, as a result of which to improve the technical and economic characteristics of autonomous power supply systems.

The problem of studying the laws governing the formation of the radon environment is not new. The development of the mining industry (to study the regularities of the formation of the radon environment in mine workings, it was necessary to simulate the flux of radon density, which led to the construction of various models of radon transfer), became the main catalyst for in-depth research in this direction. It should also be noted that according to the RF radiation safety standards (NRB-99), the average annual equivalent equilibrium volumetric activity (concentration) of radon in the air of residential and public buildings should not exceed the established limit. To implement this decree, various models of mass transfer (radon) were built. Most of these models are based on the advection-diffusion equation, which simulates the processes of mass transfer of matter or heat transfer in a medium with fractal geometry (in particular, in porous media). Moreover, the order of the fractional time derivative in this equation corresponds to the proportion of channels (the system described by this equation is open, that is, it is connected to the outside world either by a finite or infinite number of communication channels) open for flow in a fractal (porous) medium. This process is non-local in time. And the environment in which this process takes place will be an environment with memory. In this paper, we analyze boundary value problems for the considered equation. A method based on the separation of variables is presented, while the solution of the problems posed is written out in the form of an infinite series in the eigenfunctions of the operator generated by an ordinary differential expression of the fractional order (the order of the fractional derivative is greater than one but less than two) and boundary conditions of the Sturm-Liouville type.

Gas boilers for heating of individual consumers is used in all regions of Russia. Gas boilers are characterized by higher efficiency unlike on other types of organic fuels. Using dry natural gas reduces the polluting emissions into the atmosphere. A significant variety of gas boilers for individual heat supply meets the needs of consumers. The main requirements for individual heat supply from gas boilers are safety, economy, high efficiency, ease of use. These requirements are met by using gas with specified properties that meets standards. The required gas parameters for the consumer are provided due to the availability and functioning of the gas distribution system in the settlements. For the safety and efficiency of gas boilers, proper organization of air exchange in the room is necessary. To determine the efficiency of domestic gas boilers, the influence of the temperature of the air used in the combustion process is considered. Boilers with open the combustion chamber use internal air. Outside air is used in boilers with a closed combustion chamber. The study determines how the efficiency of a gas boiler changes at different temperatures outside air during the heating period. Losses of flue gases and chemical incomplete burning were taken into account when calculating the efficiency of gas boilers. The calculation was made taking into account the physical heat introduced by the air for burning. The study considered gas boilers with a heating capacity of 20, 30, 50, 100kW at a nominal operating mode. The annual effect of gas fuel saving is presented for natural dry gas with a calorific value of 34MJ/cub m.

The paper provides a brief analysis of the history of urban development, depending on the consideration of natural and climatic conditions, in particular, the movement of air masses. The construction practice is taken into account when accounting wind conditions, which primarily involves the effective placement of industrial enterprises, sanitary break zones, residential development and public space. Theoretical studies of the aerodynamic properties of two models of buildings of simple shape, based on some experimental data, are presented. Comparing the flow directions calculated theoretically with the directions measured experimentally by different authors, it is confirmed that the proposed theoretical methods well reflect the actual picture of the flow around a rectangular profile by an air flow. For the considered models No. 1 and No. 2, according to the test results, it was determined that the pressure on the windward planes (walls) of different heights depends on the ratio between the thickness of the boundary layer and the height of the building, respectively, buildings of small height are almost entirely located in the boundary layer, i.e. in the layer of air, which, touching the surface of the earth, is slowed down due to the roughness of the underlying surface, as the speed of air movement decreases as it approaches the surface of the earth, and on the surface it is zero.

Knowing the specific technological parameters of water source and piping systems, it is possible to determine the service life of the pipe set, as water source as pipelines, by the offered method. Complex-acting, multifunctional, thermally resistant, bactericidal type new corrosion inhibitor based on naphthenates has been developed; The technology of insulation of the surface of metal pipes with coatings made of non-corrosive, shock-resistant and corrosion-resistant basalt-plastic and glass-plastic materials has been developed. Possibility of application of basalt-plastic and glass-plastic materials in construction and repair of tanks and other capacities was studied; Technologies for the production of protective belts, transport pipes, as well as rods from pure basalt-plastic and fiberglass materials in the highly corrosive environment were developed and their application together with metal pipes and rods was analyzed. Knowing the specific technological parameters of water source and piping systems, it is possible to determine the service life of the pipe set, as water source as pipelines, by the new method. During the research, the physicochemical factors affecting the object were investigated and methods of elimination were developed: Innovative methods of corrosion protection to increase the service life of equipment and transport pipelines, as well as a statistical method to determine the dependence of the capacity of equipment and transport pipelines on mechanical, physical and chemical factors; complex-acting, multifunctional, thermally resistant, bactericidal type new corrosion inhibitor based on naphthenates has been developed.