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RESTORATION OF THE ENTERPRISES OF THE ELECTRICAL,
MACHINE-BUILDING, CHEMICAL INDUSTRY OF KALININ
AFTER LIBERATION FROM THE NAZI OCCUPATION
Authors: L.A. Bоlokina
Abstract: The article discusses the process of restoring Kalinin power plants, power grids, and establishing production at the Kalinin Wagon Plant and the Kalinin Rubber Sole Plant in the end of 1941 – beginning of 1942. The scale and nature of the destruction, the stages of restoration work are shown. The reasons that slowed down the recovery were identified: an acute shortage of energy resources, transport, equipment and tools, but above all qualified personnel.
Keywords: Great Patriotic War, restoration work, Kalinin Carriage Factory, Kalinin Plant of Rubber Soles (Kalinin Rubber-Sole Plant), qualified personnel, workshops, power plants, power grids.
CONSIDERATION OF ERECTION STAGE IN DESIGNING MONOLITHIC
Authors: T.R. Barkaya , A.V. Gavrilenko , A.V. Levikov , A.V. Shevkina
Abstract: The article presents general approaches to the assignment of compression forces in the calculation and design of post-stressed monolithic structures, taking into account the technology of their further construction. The interrelationships of the stages of construction and operation and the technical and economic parameters of the design solution are shown. The mutual influence of design and technological solutions is considered based on the analysis of a number of relevant factors that determine the optimal performance of the project as a whole.
Keywords: reinforced concrete, post stress, stress without coupling, monostrend, concrete crumpling, monolithic works, concrete holding.
EXPERIMENTAL STUDY OF PUNCHING SHEAR OF UNBONDED
POST-TENSIONED REINFORCED CONCRETE SLABS
Authors: A.V. Gavrilenko, A.V. Levikov, T.R. Barkaya, D.A. Hanygin
Abstract: In this paper there is description of three-layer tongue-and-groove expanded clay concrete blocks, traded under mark “Balaev block”. Their main advantages and disadvantages are listed. It is shown, that there are difficulties with lintel placing above windows and doors in walls of individual houses, made of these blocks. It is connected with insufficiency of compressive strength of internal expanded clay concrete layer under acting of local compressive loads. Experimental study of three blocks were conducted. Blocks were exposed to acting of local compressive loads. Compressive test results are given. Variables were the placing and dimensions of a stamp. Conclusion is made that in some cases bearing capacity of the blocks is sufficient for placing lintels on internal layer without constructing extra bearing elements.
Keywords: expanded clay concrete, concrete blocks, local loading, compressive test.
USE OF FRACTAL THEORY IN THE ASSESSMENT OF AGRICULTURAL AREAS
Authors: N.P. Kurbatov
Abstract: The article is devoted to the actual problem of using mathematical apparatus to solve problems of urban planning and agriculture. The use of fractal theory makes it possible to develop methods of express forecasting and zoning of drainage and irrigation reclamation.
Keywords: fractal, urban planning analysis, express forecasting.
STUDY OF GEOMETRIC AND THERMAL PARAMETERS OF WALL CERAMSITE
CONCRETE BLOCKS WITH A DECORATIVE FACADE
Authors: A.V. Levikov, A.V. Gavrilenko, T.R. Barkaya, D.A. Hanygin
Abstract: The article presents the results of a study of the geometric parameters of tongue-and-groove expanded clay concrete blocks with a decorative facade. The thermal conductivity coefficient of the expanded clay concrete layer was determined in a natural way and the heat transfer resistance of the block as a whole was calculated. The substantiation of the possibility of using blocks in housing construction as an energy-efficient material is presented. Recommendations are given for further improvement of the block production technology in order to improve the accuracy of the internal geometric parameters of each of the block layers.
Keywords: expanded clay concrete, wall blocks, energy efficiency.
TO THE ISSUE OF ROAD CONSTRUCTION IN SWAMPS
Authors: V.I. Trofimov
Abstract: The article deals with the current problem of increasing the efficiency of road construction on weak soils. When erecting transport facilities in swamps, it is necessary to take into account the complex natural and climatic conditions of construction, the high degree of compressibility of peat soils and the high cost of work. In addition to the features of soil conditions that affect the stability of roads in swamps, it is necessary to improve the methodology for calculating the behavior of the embankment on a weak peat base and the technology for their construction. The high cost of construction and the increased labor intensity of the construction of transport infrastructure on swamps and soils require the development of new design solutions. The issue of choosing a calculation model for assessing the stability of the embankment on a weak peat base is being considered. It is proposed to take into account in the calculation model the inertial component that occurs when filling the embankment. An original technology for erecting a road embankment on a swamp has been developed.
Keywords: road construction, foundation, peat soils, swamps, design model, inertia force.
SUSTAINABILITY ISSUES AND METHODOLOGY
URBAN SETTLEMENT SYSTEMS IN THE CONTEXT OF A PANDEMIC
Authors: V.V. Fedorov, M.V. Fedorov
Abstract: From the standpoint of system analysis, various aspects of the formation of the problem field (ensuring the stability of the functioning of territorial settlement systems) are considered. The features of the multi-level settlement systems of the Russian Federation are determined. The methodology of solving problems of various levels is discussed. It is shown that in the analyzed situation, a specific scientific methodology prevails, dealing with technical rules, regulations, and methods of scientific substantiation of conceptual and design solutions. Along with the problems of reconstruction of the architectural and landscape environment, the problems of improving models and channels of social interaction, as well as the dissemination of ideas about "correct" behavior, creating an ideological basis for the unhindered implementation of measures to counter the epidemiological threat are considered.
Keywords: settlement system, stability of urbanized territories, epidemiological threat, methodology of problem field formation.
ELASTIC-PLASTIC STABILITY OF THE STEEL ROD 45
UNDER COMBINED LOADING
Authors: S.V. Cheremnykh
Abstract: The problem of bifurcation of a pivotally supported rod under simple combined subcritical loading is solved, taking into account the elastic and elastic-plastic stages of material deformation. Let us consider the behavior of a rectilinear rod in a certain elastic-plastic system exposed to external forces in the plane of the deviator space of deformations of A.A. Ilyushin Э Э 1 3 . The obtained graphs show that the loss of stability of the rod develops very slowly during the growth of the load and in practice it is difficult to notice it. Calculated formulas for the critical load are obtained. It is shown that, depending on the operating conditions of the rod in the structure, the critical load can be any of the range from the relative-modular Engesser value to the Euler value, excluding the Euler value itself, which is achieved only by an elastic rod.
Keywords: rod, combined loading, bifurcation, deflection, tangential-modular theory, reduced-modular theory
WHAT HAPPENS OF A LENGTHENING OF TIME SERIES
FOR ELECTRICAL CONDUCTIVITY OF THE PRECIPITATION IN TVER
Authors: F.V. Kachanovsky
Abstract: A statistical analysis of the parameters of the specific electrical conductivity of atmospheric precipitation that fell in Tver in 2016–2020 and the relationship of electrical conductivity with acidity and precipitation amount, as well as with air temperature has been carried out with an extension of the series of observations by one year. One-factor and multifactor regression models of relationships between electric conductivity and meteorological factors of the lengthened series were constructed.
Keywords: specific conductivity, acidity, precipitation, air temperature, model, correlation, regression, factors, trend, seasonal component, pH acidity index.
ECONOMIC AND MATHEMATICAL MODEL OF OPTIMIZATION OF REPAIR
AND PREVENTIVE MAINTENANCE OF ELECTRIC MOTORS WITH DIAGNOSTICS
OF THE INSULATION CONDITION
Authors: G.S. Kuzmin
Abstract: The article presents a probabilistic, economic and mathematical model and the output of the objective function for optimizing the frequency of maintenance of electric motors, taking into account operational preventive tests of electrical insulation and complete emergency repairs in case of failure.
Keywords: electric motor, repair, prevention, maintenance, distribution function, reliability, time to failure, electrical isolation, objective function, probability model.
INFLUENCE OF ATMOSPHERIC SMOKE AND SLAG HEIGHT
ON HEAT EXCHANGE IN ARC STEEL MELTING FURNACES.
PART II. INFLUENCE OF SLAG HEIGHT ON WALL THERMAL LOADS
AND ELECTRICITY CONSUMPTION
Authors: A.N. Makarov
Abstract: electric steel, electric arc, heat exchange, heat radiation, furnace.
Keywords: The influence of the height of the slag layer on the thermal loads on the watercooled panels of the walls of arc steel-making furnaces was investigated. The fluxes of thermal radiation from arcs to water-cooled wall panels are maximum when the arcs are not buried and the atmosphere of the furnace is transparent. With an increase in the height of the slag layer and the absorption capacity of the furnace dust and gas atmosphere, the thermal loads from the arcs on the water-cooled wall panels decrease and reach a minimum when the arcs are completely immersed in the slag and the maximum absorption coefficient of the furnace dust and gas atmosphere.
METHOD SELECTION AND QUANTIFICATION CONTENT
OF CHLORIDE IONS IN CONCRETE SAMPLES
OF BRIDGE STRUCTURES
Authors: V.V. Belov, V.I. Lutsik, Yu.V. Chursanov
Abstract: The paper considers the choice of methodology and quantitative determination of chloride ion content in concrete samples of bridge structures and other transport facilities, which are subject to increased requirements for corrosion resistance and durability. The violation of the passive film protecting the metal reinforcement in reinforced concrete is largely possible due to the penetration of aggressive chloride ions to the steel surface. Therefore, timely monitoring of chloride ion content in concrete samples of bridge structures is necessary to ensure the effective operation of these critical engineering structures.
Keywords: chloride ions, concrete, reinforcement corrosion, bridge structures.
INVESTIGATION OF THE EFFECTIVENESS OF SUPERPLASTICIZERS
BASED ON POLYMETHYLENE NAPHTHALENE SULFONIC ACIDS
AND POLYCARBOXYLATE ESTERS
Authors: Y.Y. Kuryatnikov
Abstract: The article presents the results of experimental studies to determine the effectiveness of superplasticizers based on sulfated melamine formaldehydes, sulfated naphthalene formaldehydes and polycarboxylate esters, the mechanisms of their action are given.
Keywords: superplasticizer, chemical additive, technical lignosulfonates, sulfonated melamine formaldehyde, sulfonated naphthalene formaldehydes, water-reducing effect.