Факультет архітектури, будівництва та енергетики
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Item type:Наукова стаття, Theoretical analysis of the microrelief of typical machine-made surfaces by SEM photogrammetry(2024) Boyarska, Inna; Homon, Sviatoslav; Kulakovskyi, Leonid; Kulakovskyi, LeonidThe article analyzes digital elevation models (DEMs) of typical mechanically formed surfaces. The theoretical issues of 3D modeling of typical "ideal" surfaces obtained, for example, by artificially growing single crystals, forming regular microrelief of materials, etc. are considered. For this purpose, the most typical stepped, spherical, cylindrical, and cubic machined microrelief surfaces were selected. The algorithms for analytical photogrammetric and digital processing of SEM stereo images are presented and illustrated by relevant examples. The results of numerical integration for different surfaces are consistent with a typical "stepped" surface.Item type:Наукова стаття, Designing reinforced plywood panels through deformation methods(2025) Gomon, Petro; Drobyshynets, Serhii; Smal, Mariia; Dziubynska, Oksana; Uzhegova, Olga; Golyk, Yolana; Kaynts, Diana; Kutsyna, IrynaA deformation methodology for theoretical and mathematical modelling and calculation of composite-reinforced plywood panels is proposed. The stages of the stress-strain state of a reinforced bending wooden element (plywood panel) with metal reinforcement are presented. An algorithm for constructing a ‘moment-curvature’ graph of a reinforced wooden element (plywood panel) is proposed.Item type:Наукова стаття, Establishing patterns in the formation of a fire-resistant sip panel with hemp insulation(2026-02-27) Tsapko, Yuriy; Tsapko, Аleksii; Berdnyk, Oksana; Likhnyovskyi, Ruslan; Bielikova, Kseniia; Slutska, Oksana; Borysova, Anna; Lomaha, Vasyl; Uzhehova, Olha; Chaikovskiy, VitaliiThis study investigates the process that forms fire-resistant properties of SIP-panels with hemp insulation based on reactive coating and lime. The task addressed is to ensure the stability of SIP-panels and components when treated with coatings to changes in operating conditions. This is important since production from renewable sources for construction is a relevant issue. It has been proven that during thermal action on samples of hemp insulation treated with reactive coating and lime, no ignition and flame spread along the surface occurred. A layer of foam coke formed on the surface of the sample treated with reactive coating, which is 22 mm. The study has shown that when a burner is applied to a sample of SIP-panels with hemp insulation treated with reactive coating, after 110 s of thermal exposure, the process of forming a heat-insulating layer of coke began, which inhibited heat transfer. Instead, after the burner was exposed to a sample of SIP panels with hemp insulation treated with lime, a charring process occurred at the site of thermal action, but ignition and flame spread did not occur. Based on the results of determining the strength, it was found that treating the surface of hemp insulation with a coating increases the tensile strength by more than 2.5 times. Thus, increasing the amount of reactive coating on the surface of hemp insulation by half increases the tensile strength by 2.3 times. In the case of treating hemp insulation with lime, the tensile strength decreases by 3.4 times while increasing the amount of lime when treating the surface of hemp insulation to 0.38 kg/m2 increases the tensile strength by 5.3 times. Thus, there is reason to argue about the possibility to design effective and operationally stable biocomposites for construction.Item type:Наукова стаття, Study of wood deformation indicators after exposure to acidic environments(2026) Vereshko, Oleg; Boyarska, Inna; Uzhegova, Olga; Shevchuk, Pavlo; Uzhehov, Serhii; Homon, Sviatoslav; Gomon, Svyatoslav; Gomon, PetroExperimental studies were conducted on the deformation indicators of structural birch and pine wood under the influence of various acidic environments with different impregnation times. The deformation parameters of all studied wood species were determined experimentally, in particular the critical uc,0,d,agr and residual deformations uc,fin,agr. It has been established that exposure to an acidic environment increases the deformation characteristics of structural timber.. Specifically, the relative critical deformations of the studied species increased within the range of 1.12 to 1.17 times after 28 days of impregnation compared to the samples tested at the standard moisture content of 12%, and within the range of 1.14 to 1.19 times after 180 days. Residual deformations increased 1.1 to 1.25 times after 28 days of impregnation, and after 180 days, they remained practically the same. Over the following five months, the strength and deformability characteristics changed insignificantly, they stabilized. This is explained by the fact that after 28 days of impregnation, the wood is almost completely saturated with moisture and subsequently hardly absorbs any more.Item type:Наукова стаття, The influence of repeated low-cycle loads on the stress-strain state of steel-reinforced concrete drainage gutters(2026) Andriichuk, Oleksandr; Yasiuk, Ivan; Uzhegova, Olga; Uzhehov, SerhiiThe paper presents the results of experimental studies on the effect of repeated low-cycle loading on the stress–strain state of steel fiber reinforced concrete gutters. A comparison was made between the effects of single and repeated loadings. Overall, the findings demonstrate that steel fiber reinforced concrete gutters have higher resistance to cyclic loading compared to single loading, and they better withstand repeated impacts without significant material failure.Item type:Наукова стаття, Modelling the optimal switching scheme of the Ukrainian power grid during blackout (Volyn region)(2024-05-29) Hrytsiuk, Iryna; Volynets, Vladyslav; Komenda, Nataliya; Hrytsiuk, Iryna; Hadai, AndriiThe relevance of the study, in particular, in the Volyn region, is due to the need to ensure the reliability and efficiency of the energy infrastructure in the face of growing challenges associated with the war between Russia and Ukraine, technological development and ensuring the country’s energy security. The purpose of the study is to develop a model of the optimal switching scheme for the Volyn region’s power grids during blackout to minimize the negative consequences and ensure priority power supply to critical facilities. The methods used include mathematical modelling, simulation, optimization, sensitivity analysis, and others. The study optimized the power grid switching scheme under the risk of war and other crisis situations, including a thorough analysis of various options in the event of a blackout. Taking into account additional aspects of grid safety and reliability, the optimal routes for power transmission, placement of backup power sources were identified and effective algorithms for grid management were developed. By optimizing the grid switching scheme, the damage caused by blackouts can be minimized, and power supply can be restored quickly. The results confirmed that an optimal switching scheme can significantly reduce blackout time and its impact on the economy and the lives of the population. The development of optimal switching schemes for power grids is an important step towards increasing the resilience of Ukraine’s electricity system to crisis situations. The study has highlighted the importance of developing such models to ensure energy security and resilience of the power grid under the threat of blackouts, which affects the practical aspects of power supply management and economic development. The practical significance of the study is to improve strategies for managing the power grid in blackout conditions, contributing to the resilience of energy systems and economic development.Item type:Наукова стаття, Prospects for the integration of distributed energy sources into the Ukrainian power grid(2025-02-27) Hrytsiuk, Iryna; Volynets, Vladyslav; Hrytsiuk, Yurii; Bandura, Irina; Komenda, NataliyaThe integration of distributed energy sources (DES) into the Ukrainian power grid is a critical aspect of modern energy development aimed at increasing the efficiency of the power system, reducing greenhouse gas emissions, and improving the country’s energy security. The purpose of this overview and analysis study was to identify the technical and automation aspects of DES integration, as well as to determine the prospects and challenges associated with their adaptation to centralised grids. The study discussed the principal technical challenges arising from the integration of solar, wind, bioenergy, and other DES into the Ukrainian power grid. Particular attention was paid to the issues of stability and quality of electricity supply, the need to modernise the grid infrastructure, and the use of inverter technologies, energy storage systems (ESS), and hybrid microgrids. The study analysed modern methods of automation and control of distributed generation using Smart Grid, Supervisory Control and Data Acquisition (SCADA), and Distributed Energy Resource Management System (DERMS) technologies, which help to optimise the operation of the power system, increase its reliability and flexibility under variable load conditions. The study considered adaptive control algorithms, mathematical forecasting models, and neural network algorithms that enable prompt adjustment of equipment operating modes, ensuring the stability of the system. It was found that the introduction of inverter systems, SPPs, and hybrid microgrids can re solutions that include the use of renewable energy sources, DERMS, and smart management. The recommendations included infrastructure modernisation, development of hybrid ESSs, and implementation of integrated digital monitoring and control systems. The practical value of this study lies in the development of approaches to the effective integration of DES into local power systems, which can be used in the design and implementation of microgrids in Ukraine.