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Klyuev S.V.

Doctor of Engineering Sciences (Advanced Doctor), Associate Professor, Belgorod State Technological University named after V.G. Shukhov, Russia

Specifics of information model development for functional conversion of offshore oil platforms

https://doi.org/10.58224/2618-7183-2023-6-4-42-57
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 42-57 p.
Abstract
The paper holds that the disposal of offshore oil platforms (OOP) after the expiration of their lifecycle is inexpedient and unjustified from the environmental standpoint, since this process results in a dramatic adverse impact imposed on the hydrosphere, which explains the relevance of OOP conver-sion into objects with other functional purposes. The focus is on the global experience of converting offshore oil platforms into residential and industrial buildings. Special attention is paid to the fact that the conversion of an object leads to a reduced construction timeline, which is possible due to optimiz-ing the timeframe of dismantling works that become unnecessary during the subsequent operation of the OOP structural parts. The point is emphasized that OOP repurposing, and in particular creating so-called floating cities on their basis, is capable of meeting a handful of environmental, socioeconomic and town-planning challenges, which however calls for a rigorous professional approach and a thor-ough study of the OOP lifecycle stages both before and after their functional conversion. This, in turn, may lay the ground for the development of an information model of OOP functional repurposing. The research is aimed to explore the specifics of developing an information model of OOP conversion into other type facilities, and as such identifies the key OOP types (submersion depth and underwater de-sign solutions, principal advantages and disadvantages) required to build individual information blocks to form part of the overarching information model of OOP conversion. Also, a scheme of information environments is provided showing the algorithm of creating an information model of OOP conversion and singling out the stages of various lifecycle phases.
The conclusion is made that the functional repurposing of offshore oil platforms is required to as-sure safety of the natural environment, suggesting that the assessment of the environmental perfor-mance and energy efficiency of the organizational and technological solutions of OOP functional con-version must be made part of the front-end design engineering milestone.
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Method for calculating the strength of massive structural elements in the general case of their stress-strain state (kinematic method)

https://doi.org/10.58224/2618-7183-2023-6-3-5-17
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 5-17 p.
Abstract
A variant of the kinematic method of the theory of limit equilibrium is proposed; massive structural elements are considered, the material of which, in the general case, is anisotropic.
A rigid-plastic model of a deformable solid body is adopted. It is assumed that massive structural ele-ments are destroyed by dividing into parts that deform relatively little (“absolutely rigid finite ele-ments”, ARFE) and have 6 degrees of freedom in three-dimensional space. The process of destruction of the material goes along infinitely thin generalized destruction surfaces (GDS), on which the work of all acting internal force factors (IFF) is taken into account – 9 forces and 9 moments. Bodies made of homogeneous isotropic materials that resist tension and compression in different ways are considered. The strength surfaces in the IFF space are described by the corresponding parametric equations.
Using the equilibrium equation in the Lagrange form and the Mises maximum principle, as well as the proposed parametric equations of the limiting surface, the problem of determining the minimum value of the possible kinematic parameter of the load is reduced to a standard linear programming problem (LP), which is solved using the simplex method.
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Experimental studies of the processes of structure formation of composite mixtures with technogenic mechanoactivated silica component

https://doi.org/10.58224/2618-7183-2023-6-2-5-18
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 5-18 p.
Abstract
The paper considers the issues of utilization of technogenic fibrous material – waste of basalt production. The chemical composition of the technogenic fibrous material was studied, it was found that it consists of 44% SiO2. The initial basalt rock, which undergoes changes during high-temperature processing in the process of obtaining basalt fiber, was studied using IR spectroscopy. The grinding of the crowns was carried out for 30 minutes, allowing to reach a specific surface area of 800 m2 / kg. Further grinding does not lead to an increase in the specific surface area, which is associated with the phenomenon of secondary aggregation of fine particles. Research on REM has shown that the “cold shots” before grinding are mostly rounded or oval in shape. The compositions were formed and the strength characteristics of the samples for the 3rd and 28th day were determined. The maximum strength gain of 59 MPa was established at the age of 28 days in samples with the addition of 5% ground “cold shots” . When introducing cold shots in an amount of 10% (composition 5) of the cement mass, an intensive strength gain is noted in the early stages of hardening (7 days) with a strength of 38 MPa, slightly higher than the strength of the control composition. The introduction of 15% ground “cold shots” gives a strength value slightly lower (32 MPa) than the values of the control composition (37 MPa) at all stages of hardening.
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Method for calculating the strength of massive structural elements in the general case of their stress-strain state (parametric equations of the strength surface)

https://doi.org/10.58224/2618-7183-2023-6-2-104-120
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 104-120 p.
Abstract
In the mechanics of a deformable solid, there are rods (one overall dimension of which is significantly larger than the other two), plates and shells (one dimension of which is significantly smaller than the other two), arrays (all three dimensions of which are of the same order). The complexity of the corresponding calculation models grows in the same order: the calculation models for rods and rod systems are relatively simple, the most complex are the calculation models for massive structural elements.
In the work, parametric equations of the strength surface in the space of internal force factors (IFF) are obtained – 9 forces and 9 moments for homogeneous anisotropic bodies. As special cases, similar equations are given for isotropic bodies that resist tension and compression differently, for isotropic bodies that equally resist tension and compression. Algorithm A1 for constructing the desired sections of strength surfaces given by parametric equations is proposed. Algorithm A2 is proposed for deter-mining the safety factors for the bearing capacity, remaining in the space of the IFF. Some examples of calculations made using the proposed equations, algorithms and the corresponding computer programs compiled on their basis are given.
The proposed method for calculating massive bodies allows a more realistic assessment of the bearing capacity of massive structural elements.
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Development of Alkali-activated Binders based on Technogenic Fibrous Materials

https://doi.org/10.58224/2618-7183-2023-6-1-60-73
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 60-73 p.
Abstract
The paper discusses the development of alkali-activated binders based on technogenic fibrous materials. An approach to the secondary use of technogenic fibrous materials as a filler of composite binders is offered. The properties of mineral wool waste have been established. The microstructure of finely ground fibrous particles has been studied. Compositions of alkali-activated binders were de-veloped, when grinding basalt insulation production waste to a specific surface of 300-330 m2 /kg, followed by the formation of a binder according to the first method with rod tamping sealing and, ac-cording to the second, by pressing a raw binder mixture at a pressure of 10 MPa. The developed com-positions of alkali–activated binder by pressing with a compressive strength of 22.8 MPa, and when compacted with subsequent rod tamping – 11.8 MPa.
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Plasma electrolyte production of titanium oxide powder

https://doi.org/10.58224/2618-7183-2022-5-6-75-84
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 75-84 p.
Abstract
The work is devoted to the research of plasma-electrolyte process realized in conditions of cathodic polarity of active metal electrode and its immersion into electrolyte to produce titanium oxide micro- and nanoparticles as well as titanium oxide-coated particles up to 10 μm in size. Two modes of discharge combustion differing in heat generation and concentration of electrolyte solution on particle size distribution were found to influence. Voltage increase can result in discharge combustion in arc mode due to thermal emission of electrons and intensive heating of titanium cathode. This, in its turn, leads to formation of titanium particles up to 10 μm in size, which surface is oxidized. It was found that discharge combustion in the regime with less heat emission leads to formation of titanium oxide particles sized less than 1 µm. These powders can be used in additive manufacturing, powder metal-lurgy and as additives in composite materials.
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Universal Laws of Composition (Artificial and Natural Form) on the Example of the V.G. Shukhov Tower

https://doi.org/10.58224/2618-7183-2022-5-5-29-41
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 29-41 p.
Abstract
The authors of the article broadcast information about the study of the compositional activity of engineers in Soviet Russia in the 20s of the XX century. in line with the architectural trend "con-structivism". The study, analysis and fixation in graphic images of masterpieces of volume-spatial composition in the history of engineering, scientific thought is considered by the authors as an isola-tion from an artificially created object – an organism of universal laws and means. The authors believe that the study, analysis and fixation in a schematic graphic material of high-class samples of science, technology, engineering allows you to develop compositional thinking, taste and teaches you to under-stand the course and origins of compositional thought in design. The study of the formal (composi-tional) sphere of the Legacy of the classics of modern and past eras allows you to build the path of the author's work on the project, avoiding mistakes and disappointments.
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Study of the plasma-electrolyte process for producing titanium oxide nanoparticles

https://doi.org/10.58224/2618-7183-2022-5-5-70-79
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 70-79 p.
Abstract
The work is devoted to the investigation of the process of obtaining titanium oxide nanoparticles by burning high voltage DC gas discharge in an argon atmosphere when an aqueous solution is used as one of the electrodes. It was found that using an aqueous glycine solution in an inert gas medium, the plasma-electrolyte process using a streamer discharge is well suited for producing titanium oxide nanoparticles. An important regularity of particle size decrease with the increase of argon pressure in the chamber was revealed. Thus, when the pressure is increased from 1 MPa to 3 MPa, a sharp decrease in the average particle size from 62 nm to 16 nm is observed, while the changes in the aver-age particle size are not cardinal already in the process of pressure increase up to 5 MPa. A narrowing of the dispersion composition scatter with increasing pressure for 1 MPa - ± 40 nm, 3 MPa - ± 20 nm and 5 MPa - ± 8 nm was determined. The presence of titanium oxide particles was confirmed on the basis of plasmon resonance detection at 224, 230 and 235 nm.
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RESULTS OF ENDURANCE TESTING OF PREFABRICATED CRANE STRUCTURES

https://doi.org/10.58224/2618-7183-2022-5-4-39-49
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 39-49 p.
Abstract
The purpose of the work is to analyze the results of tests of prefabricated crane beams for endurance during cyclic tests on a specially designed stand. The method of carrying out such tests is given. It indicates the inadmissibility of the operation of steel crane structures with cracks and the importance of research aimed at increasing the endurance and durability of crane beams. It proves the need to develop new crane beams (various profiles) to increase the period of accident-free operation of industrial buildings (using bridge lifting mechanisms with heavy duty) up to 25 years. It is proved that the developed prefabricated crane beam has improved (in comparison with the standard) characteristics.
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TECHNOLOGICAL FEATURES OF THE CONSTRUCTION OF A DEMOUNTABLE FOUNDATION FOR TOWER STRUCTURES

https://doi.org/10.58224/2618-7183-2022-5-3-17-26
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 17-26 p.
Abstract
The paper proposes a new type of modular demountable reinforced concrete foundation for the construction of tower-type structures. Numerical modeling and design features of the manufacture and installation of the foundation, implemented under patent 2633604 “Demountable foundation for support” for a real tower with a height of 30 meters and a power of a 150 kV wind power plant, are given. The reduction of material consumption is achieved due to the formation of a cavity in each typical module and filling it with soil or any inert material. The result of the proposed solution is to increase the bearing capacity of the foundation as a whole, increase the strength and rigidity of its main joints, as well as simplify installation in comparison with traditional approaches to design. Moreover, the foundation modules, where maximum stresses occur, can be made of fibre concrete.
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