bluuebunny/crossref_metadata_2025_split huggingface dataset:
Justification of conditions of application of thermo modified veneer for protection of wooden products from moisture
Authors: Tsapko Y , Horbachova O , Bondarenko O , Mazurchuk S 
Published: July 2021

AbstractThe analysis of the process of thermal modification of wood was carried out and it was found that the treatment causes chemical changes in the structures of wood components (lignin, cellulose and hemicellulose). It is proved that in the process of thermal modification there is a decomposition of hemicelluloses and amorphous part of cellulose, reduced water absorption, and also reduces the amount of substances that are the environment for the development of fungi, which leads to increased durability. In addition lignin and psevdolihnin formed by the process of polymerization and pererozpodilynyu in cell volume and cell walls provide higher density, hardness, increase the hydrophobicity (water repelling), thereby reducing their ability to absorb moisture and swell. It has been experimentally established that in comparison with unmodified veneer, which gained 22.41 % of moisture in two weeks, veneer modified at 250 and 280 °C gained 2.5 times less moisture - on average 8.6 %. It is established that with the increase of the modification temperature to 280 °C, the water absorption decreases more than twice. The results of the research will also allow to purposefully solve further problems on the creation of new methods of thermal modification of wood and the conditions of its operation at various sites.
Optimization of the calculated scheme
Authors: Medved I , Surianinov M , Otrosh Y , Pirohov O 
Published: July 2021

Abstract
Any calculation is preceded by the stage of creating a design scheme of a real design, which would most accurately respond to real operating conditions. The more optimally drawn up the calculation scheme, the less time consuming there will be stages of calculation and designing the corresponding design. There are practically no results of the use of such an approach in the calculations of building structures. This article an attempt is made to show the possibility and feasibility of using “search for solutions” (add-in for Microsoft Excel) at the stage of selecting the optimal parameters of the design scheme.
Investigation of impulse load attenuation in closed-cell foam in the framework of couple stress elasticity
Authors: Mikulich O , Shvabyuk V 
Published: July 2021

AbstractThe article analyzes the processes of attenuation of impulse loads in foam materials with closed-cell. In the framework of the couple stress elasticity, the analysis of the distribution of dynamic radial stresses in foam media with tunnel cavities of constant cross-section under the action of an impulse load of different duration applied to the cavity boundary in the radial direction is performed. An analytical-numerical approach is used for calculating of the dynamic stresses, which is based on the application of the Fourier transform over time and the modified boundary integral equation method. Numerical calculations of the dynamic stresses were performed using the method of mechanical quadrature and collocation method. The modified algorithm for discrete inverse Fourier transform was used for the calculation of the originals of the dynamic radial stresses. Based on the analysis of numerical calculations, the influence of the impulse duration on the attenuation rate of the pulse load in foam media is established.
Nonbearing Wall infill Under Seismic Impacts In Terms Of Non-Linear Static Analysis
Authors: Oleksiy Murashko , Mikola Kubiiovich , Denys Bezushko , Andrii Arsiriy 
Published: July 2021

Abstract
The presence of wall infill during seismic impacts is one of the key factors that significantly affect the seismic stability of buildings. Also, irregularity of configuration in plan and height can often lead to more serious damage comparing to regular buildings, due to torsional oscillations and stress concentration on individual elements. The purpose of this article is to study the behavior of various irregularities in the shape of buildings under seismic impacts in terms of non-linear static analysis, taking into account the non-bearing wall infill. For this purpose, five typical geometric shapes of the building plan used in Ukraine and abroad (rectangular, + shape, L-shaped, T-shaped and 4-shaped) were adopted.
The calculations were performed using the Pushover Analysis (nonlinear static analysis) method in CAD Lira-SAPR 2019. The main parameter that forms the basis for seismic stability analysis is the story drift under seismic impacts. Obtained results indicate the need to take into account the effect of wall infill, as this can lead to an increase in the seismic stability of the building and stress concentration on individual elements, which can lead to their collapse.
Portland cement easy treatability as the basis of concrete structure stable quality
Authors: Nikolaev A P , Kondrachenko E V , Kondrachenko V I 
Published: July 2021

Abstract
An opportunity is discussed to improve operational parameter stability of concrete and reinforced concrete articles on Portland cement basis in heavy-duty environment. Demonstration of binding properties of cements with identical normative parameters was shown to be dissimilar under amended operational conditions. Such behavior may be supposedly connected to insufficiently stable relation between alkalinity and dispersity of consumed Portland cement.
It was found feasible to arrange preventive control of incoming Portland cement with due consideration of its application conditions. The results of such control were shown to be efficient at substantiated correction of applied Portland cement activity.
The purpose of this research has been expansion of methodological basis of mineral binder quality control for stabilization of consumer properties of concrete and reinforced concrete structures produced on their basis.
The results of complex tests of piles during the installation of piled-raft foundations of the grain terminal in difficult soil conditions near the sea coast
Authors: Novsky O V , Marchenko M V , Mosicheva I I , Novsky V O 
Published: July 2021

Abstract
The engineering and geological conditions of the construction site for the designed terminal for processing and transshipment of grain products and its brief structural characteristics were presented; during arranging the zero cycle of the structure for the operative assessment of the accepted parameters of piles and confirmation of their calculated load, a series of dynamic and static tests of prismatic piles were carried out; requirements, normative methods, technology and devices for testing piles were given; calculations and analysis of their results and preliminary assessment of the accepted parameters of the piles were performed; the possibility of operational forecasting and adjustment of the calculated load and parameters of the piles accepted in the project in difficult geological conditions near the edge of the sea coast was shown.
Development of analytical calculation method for axisymmetric oscillations of circular and annular plates on variable Winkler elastic foundation
Authors: Krutii Yu , Surianinov M , Osadchiy V , Kolomiichuk V 
Published: July 2021

Abstract
An analytical method for calculating axisymmetric vibrations of circular and annular plates on a variable elastic Winkler base is presented. The proposed calculation method is based on the exact solution of the oscillation equation with the subsequent development of a method for its numerical implementation. To construct an exact solution, the direct integration method is used, which was previously developed by one of the authors for differential equations with continuous variable coefficients. The proposed method does not require the discretization of the considered structure and it is a real alternative to the application of approximate methods during solving this types of problems. Based on the exact solution of the differential equation, this method will allow to obtain better picture of oscillations in comparison with approximate methods. In fact, the exact solution has qualitative information and forms the most complete picture of the physical phenomenon that is researched.
Influence of the processes taking place in the contact zone “masonry - plaster coating” on the destruction of the wall structure
Authors: Paruta V , Grynyova I , Gnyp O , Lavrenyuk L 
Published: July 2021

Abstract
To create the optimal composition of the plaster solution with the preassigned properties, it is necessary to know the processes taking place in the “masonry-coating” system, including in the contact zone between it and the masonry, the mechanism of its destruction. The purpose of the presented work was to describe the processes of occurrence and growth of cracks in the plaster coating and its contact zone with the masonry, in the process of its application, hardening and operation of the wall structure. In recent years, significant progress has been made in analyzing the reliability of plaster coatings, their behavior during operation, however, there are problems in predicting the evolution of damage in terms of initiation and growth of cracks, which ultimately leads to cracking and delamination of the plaster coating from masonry. The behavior of the plaster coating largely depends on its structure and the structure of the contact zone. The state of the “masonry-coating” system was described and this made it possible to obtain data on the process of its destruction, the appearance and spread of cracks. The system was destroyed according to two main schemes: formation and development of cracks in the coating and in the contact zone. Thus, these researches make it possible to reduce the number of defects in the contact zone with the masonry and increase the service life of the wall structure.
Special aspects of exterior design of elements of stationary and mobile observation constructions
Authors: Petrovska Yu 
Published: July 2021

Abstract
The article systematizes scientific, informational, regulatory and reference literature on the research topic. Construction schemes of stationary, mobile and transportable Ferris wheels are considered, and their common and distinctive features and peculiarities are outlined. Designs of the world’s highest Ferris wheels are illustrated, the history of their creation, types, design and functional features are described. Special aspects of construction of amusement towers as objects of the short-term panoramic observation of the area are specified. The functional purpose of metal observation constructions used in the entertainment industry is discussed. The development of the tourist industry of cities with active sightseeing attractions is analyzed. Conclusions of the scientific research are drawn and prospects for the development of observation constructions as amusement facilities and landmarks of the urban environment are described.
Investigation of the Conditions for the Use of Material with the Shape Memory Effect in the Sprinklers
Authors: Petukhova O , Gornostal S , Sherbak S 
Published: July 2021

Abstract
The expediency of using nitinol, which is a material with the shape memory effect (SME), as a sensitive element (SE) of a sprinkler has been substantiated. The influence of various parameters on the SE dimensions is analyzed and it is shown that the response time of an element made of a material with the shape memory effect depends on the dimensions of the fixing device (FD) (the diameter of the glass bulb and its thickness). Calculations have shown that the use of the material minimizes the response time of the sprinkler. It is shown that the response time depends on the voltage (or current) in the electrical network, on the size of the fixing device, the cross-sectional radius of the actuator and the critical temperature at which the actuator is triggered.
Development of tools (laboratory facilities) for researching the effect of physical properties of landfill soils on slope stability
Authors: Rashkevich N , Strelec V , Shcherbak S , Yeremenko S 
Published: July 2021

Abstract
The paper presents a developed laboratory unit and a technique for conducting experimental studies of the effect of physical properties of landfill soils, such as moisture, density, temperature, on slope stability in order to verify the reliability of a mathematical model and a methodology for preventing emergencies associated with displacement developed on its basis. Conducted field studies of humidity, density, temperature of landfill soils of typical solid waste disposal facilities. The analysis of the conditions for obtaining the maximum amount of methane in the composition of biogas has been carried out. The basic requirements for the laboratory unit have been determined and the area of the factor space for conducting experimental laboratory studies has been established.
Theoretical and experimental studies of energetics of the dolomite decarbonization process
Authors: Vinnichenko V I , Riazanov A N , Rakhimov R Z , Riazanov A A , Vinnichenko O V 
Published: July 2021

Abstract
One of the known advantages of magnesia binders is a significant reduction in energy consumption for the production of such binders compared to the production of lime and Portland cement. The theoretical costs of thermal energy for firing dolomite, which amount to 220-230 kcal/kg (for Portland cement – 420-430 kcal/kg), are almost halved under equal conditions of raw material moisture and furnace efficiency. This study examines the screening of dolomite waste and coal waste materials as raw materials for the production of dolomite cement. Coal preparation wastes in this case are both the initial raw material and, in part, can be used as fuel to ignite the raw charge. Theoretical and experimental studies of the influence of the organic component of coal waste on the process of decarbonization of dolomite have been carried out. The results of thermodynamic studies show that the participation of carbon and its gasification products in the reactions of dissociation of magnesium carbonate makes it possible to reduce the temperature of the beginning of the decomposition reaction of MgCO3 and CaCO3. The energy feasibility of obtaining dolomite binders has been theoretically substantiated.
Calculation of reinforcement to concrete adhesion in reinforced concrete elements
Authors: Romashko V M , Romashko-Maistruk O V 
Published: July 2021

Abstract
A model and method for calculating of reinforcement to concrete adhesion in reinforced concrete elements have been developed. The basic parameters by means of which it is possible to control interaction of reinforcement with concrete at any stage of a reinforced concrete element deformation are defined. These parameters are associated with the processes of formation and development of normal cracks. A criterion is proposed by which it is possible to determine the adhesion forces of a reinforcing rod with concrete along its conditional cylindrical surface and to estimate, thus, the degree of violation of their interaction. It is recommended to calculate the specified efforts in the simplest way: by means of average stresses of reinforcement with concrete adhesion on sites between adjacent cracks. It is statistically substantiated that the function of these stresses is nonlinear with respect to normal stresses in the reinforcement. An analytical dependence is proposed to calculate the coefficient taking into account the profile of the reinforcement (its adhesion index to concrete).
Study of a dual frequency vibration press for the formation of concrete elements
Authors: Gordienko A , Emelianenko N , Saienko L , Younis Basheer , Dobrokhodova O 
Published: July 2021

AbstractThe article presents the results of a study of a planetary drive dual frequency vibration press for the formation of concrete elements. Mathematical modeling of the movement of the working bodies (matrix and punch) has been carried out, analytical dependences have been obtained to determine the parameters of a vibration press. The results of the study indicate the ability to control the nature of the movement of working bodies, which expands the technological capabilities. The obtained dependences make it possible to improve the methodology for calculating the parameters of a planetary drive dual frequency vibration press.
Engaging man-made waste in the closed cycle of mining production
Authors: Gorbatyuk N , Adigamov A , Shakhov S , Kobelev O 
Published: July 2021

Abstract
The problems faced by the mining and construction industries are analyzed in the article. A unified concept is formulated to eliminate the problems that arise in the region of mineral extraction, together with solving the problems of expanding the raw material base of the construction sector. The idea of rational use of man-made waste from local mining enterprises and industrial waste for the construction and backfill mixes preparation is presented. The aspects of their application as an aggregate in mixtures are considered on the example of man-made waste (halite enrichment waste). It is noted that the use of man-made waste in construction and backfill mixes must be carried out after deep additional processing. Deep processing allows to maximize the use of useful components of man-made waste and eliminate the negative consequences of harmful ones. It is established that the best way of additional processing is the activation of man-made waste in disintegrators. It is proved that activation increases the strength of structures or cemented mass by 25-30%, reduces the consumption of binder by 40-50%, while maintaining the same strength characteristics. The use of man-made waste in construction and backfill mixtures expands the raw material base for the construction and mining sectors, allows to implement the concept of sustainable development of the region, and reduces the impact on the environment.
MECHANICAL LOADING SYSTEMS SAFETY PROCESSES MODELING
Authors: Savchenko Iurii , Shapoval Alexander , Kozechko Viktoriya , Voskoboynik Volodymyr , Khrebtova Oksana , Shlyk Sergii 
Published: July 2021

Abstract
Mechanical means which are directly related to the information support path (locators, observation stations, accompaniment, detection, localization, etc.) require special attention within the framework of the technical channels of receiving information. Their accurate and stable performance is of the utmost importance. Loss of the mechanical properties occurs during operation, that is material wear. To improve the quality of mechanisms and to ensure the stability of the radio-electronic means, the authors of the paper consider the possible mode of friction geoactivators in the friction unit parts of machines. The studies of the rubbing surfaces chemical composition after being processed by the geoactivator demonstrate that the components of the geoactivator diffuse into the surface layers of the material and form glass-crystalline layers, which are the solutions of the geoactivator components in the phase components of the surfaces steels and cast irons. The studies of mechanical properties have shown that the hardness and wear resistance of the surface layer increases and the roughness of contacting surfaces gets reduced.
Ways to increase the efficiency of detection of unmanned aerial vehicles by thermal imaging devices
Authors: Shmelov Yu M , Brusakova O V , Yakovlev R P , Petchenko M V 
Published: July 2021

Abstract
The possibilities to increase the efficiency of detection of air objects due to the optimized choice of a functional area of an infrared range of electromagnetic waves are mathematically estimated. It is shown that there is a need to use receivers with maximum visibility in longer wavelengths, as well as the need to work in the “transparency windows” of the atmosphere. With low visibility, long-wavelength infrared thermal imaging devices are advantageous at long distances from objects. Devices with more shortwave sensitivity can be effective over short distances. Radar detection methods in many cases are not able to detect small objects with a low reflection coefficient, which is one of the reasons for the small effective scattering area. Known methods of observation using night vision devices and thermal imaging devices, having their advantages, are also ineffective in certain conditions. An attempt is made to combine the advantages of detecting aerial objects by the multi-position radar method with the advantages of thermal imaging devices. A method of illuminating air objects with infrared searchlights is proposed, which implies the presence of many geometrically spaced sources of infrared radiation with a working spectrum combined with areas of “windows of transparency” of the atmosphere and the maximum sensitivity of the thermal imager. In such conditions, the receiver registers the total signal of thermal radiation of the object and the reflected rays of searchlights. Remote control of the spotlight emission, on which the effective scattering area depends linearly, makes it possible to bring it to the level guaranteed with a high probability of detecting a small flying object.
Limit state of a rectangular reinforced section using elastoplastic material strain diagrams
Authors: Soroka Mykola 
Published: July 2021

Abstract
The paper considers the methodology of constructing the strength area of a rectangular reinforced section. The notion of “section strength area” is used in the calculations of structures according to the limit equilibrium. The peculiarity of the strength region is that inside the strength region the section works in the elastic stage, and at its boundary it transits to the limit state with the possibility of unrestricted plastic deformation. The equations describing the boundary of the section’s strength region are often called yield conditions. In this paper, it is assumed that the material of which the section is made and the reinforcing material deform according to the ideal elastoplastic body law. Thus, the deformation diagrams of the materials are described by the Prandtl diagram. The material, of which the section is made, has different tensile and compressive yield strengths. The reinforcing material has the same tensile and compressive yield strengths. In deriving the equations describing the boundary of the section strength area, it was assumed that the bending moment and the longitudinal force applied in the center of the rectangle act in the section. Given that the section may have asymmetrical reinforcement, different equations are used to describe the upper and lower boundaries of the strength area. In order to construct the strength area, it is necessary to solve the optimization problem of finding the extreme value of the moment taking into account the constraints (equations and inequalities) for a given value of the longitudinal force. The analysis of results obtained in this way for a symmetrically reinforced cross-section made it possible to propose a simpler technique for constructing the strength area of a rectangular reinforced cross-section without solving the optimization problem.
Expanded clay concrete mixtures and concretes on carbonate sand propertie improvement
Authors: Stolevich I A , Kostyuk A I , Kravchenko S A , Posternak O O 
Published: July 2021

Abstract
Results of researches of properties of expanded clay concrete on carbonate sand, mixtures and concrete, as well as a technique for selecting optimal concrete compositions for monolithic load-bearing and enclosing structures of residential and public buildings and structures are given.