Browsing by Author "Beskopylny, Alexey N."

Now showing 1 - 19 of 19

Citation - WoS: 52
Citation - Scopus: 62
Analytical Review of Geopolymer Concrete: Retrospective and Current Issues
(MDPI, 2023) Meskhi, Besarion; Beskopylny, Alexey N.; Stel'makh, Sergey A.; Shcherban, Evgenii M.; Mailyan, Levon R.; Shilov, Alexander A.; El’shaeva, Diana; Shilova, Karolina; Karalar, Memduh; Aksoylu, Ceyhun; Özkılıç, Yasin Onuralp
The concept of sustainable development provides for the search for environmentally friendly alternatives to traditional materials and technologies that would reduce the amount of CO2 emissions into the atmosphere, do not pollute the environment, and reduce energy costs and the cost of production processes. These technologies include the production of geopolymer concretes. The purpose of the study was a detailed in-depth analytical review of studies of the processes of structure formation and properties of geopolymer concretes in retrospect and the current state of the issue. Geopolymer concrete is a suitable, environmentally friendly and sustainable alternative to concrete based on ordinary Portland cement (OPC) with higher strength and deformation properties due to its more stable and denser aluminosilicate spatial microstructure. The properties and durability of geopolymer concretes depend on the composition of the mixture and the proportions of its components. A review of the mechanisms of structure formation, the main directions for the selection of compositions and processes of polymerization of geopolymer concretes has been made. The technologies of combined selection of the composition of geopolymer concrete, production of nanomodified geopolymer concrete, 3D printing of building structures from geopolymer concrete, and monitoring the state of structures using self-sensitive geopolymer concrete are considered. Geopolymer concrete with the optimal ratio of activator and binder has the best properties. Geopolymer concretes with partial replacement of OPC with aluminosilicate binder have a denser and more compact microstructure due to the formation of a large amount of calcium silicate hydrate, which provides improved strength, durability, less shrinkage, porosity and water absorption. An assessment of the potential reduction in greenhouse gas emissions from the production of geopolymer concrete compared to the production of OPC has been made. The potential of using geopolymer concretes in construction practice is assessed in detail.
Citation - WoS: 3
Citation - Scopus: 4
Behavior of Functionally Graded Carbon Nanotube Reinforced Composite Sandwich Beams With Pultruded Gfrp Core Under Bending Effect
(Frontiers Media Sa, 2024) Madenci, Emrah; Özkılıç, Yasin Onuralp; Bahrami, Alireza; Hakem, İbrahim Y.; Aksoylu, Ceyhun; Asyraf, Muhammad Rizal Muhammad; Beskopylny, Alexey N.
A novel generation of composite sandwich beams with laminated carbon fiber-reinforced polymer skins and pultruded glass fiber-reinforced polymer core materials was examined for their flexural behavior. The strength and failure mechanisms of the composite sandwich beams in flatwise and edgewise configurations were investigated using three-point static bending tests. These sophisticated composite structures must be designed and used in a variety of sectors, and our research provides vital insights into their performance and failure patterns. In comparison to the reference specimens (FGM-1), the carbon nanotube-reinforced specimens' bending capacity was affected and ranged from -2.5% to 7.75%. The amount of the carbon nanotube addition had a substantial impact on the beams' application level and load-carrying capacity. Particularly, the application of 0.5 wt% additive in the outermost fiber region of the beams, such as in FGM-4, led to an increase in the bending capacity. However, the stiffness values at the maximum load were decreased by 0.3%-18.6% compared to FGM-1, with the minimum level of the decrease in FGM-4. The experimental results were compared with the theoretical calculations based on the high-order shear deformation theory, which yielded an approximation between 11.99% and 12.98% by applying the Navier's solution.
Citation - WoS: 47
Citation - Scopus: 49
Composition Component Influence on Concrete Properties With the Additive of Rubber Tree Seed Shells
(MDPI, 2022) Beskopylny, Alexey N.; Shcherban, Evgenii M.; Stel'makh, Sergey A.; Meskhi, Besarion; Shilov, Alexandr A.; Varavka, Valery; Evtushenko, Alexandr
The growth in the volume of modern construction and the manufacture of reinforced concrete structures (RCSs) presents the goal of reducing the cost of building materials without compromising structures and opens questions about the use of environmentally friendly natural raw materials as a local or full replacement of traditional mineral components. This can also solve the actual problem of disposal of unclaimed agricultural waste, the features of which may be of interest to the construction industry. This research aimed to analyze the influence of preparation factors on concrete features with partial substitution of coarse aggregate (CA) with rubber tree (RT) seed shells and to determine the optimal composition that can make it possible to attain concrete with improved strength features. CA was replaced by volume with RT seed shells in an amount from 2% to 16% in 2% increments. Scanning electronic microscopy was employed to investigate the structure of the obtained concrete examples. The maximum increase in strength features was observed when replacing coarse filler with 4% RT seed shell by volume and amounted to, for compressive and axial compressive strength (CS) and tensile and axial tensile strength (TS) in twisting, 6% and 8%, respectively. The decrease in strain features under axial compression and under axial tension was 6% and 5%, respectively. The modulus of elasticity increased to 7%. The microstructure of hardened concrete samples with partial replacement of CA with RT seed shells in the amount of 2%, 4% and 6% was the densest with the least amount of pores and microcracks in comparison with the structure of the sample of the control composition, as well as samples with the replacement of CA with RT seed shells in an amount of more than 6%. The expedient effective replacement of CA with RT shells led to a reduction in battered stone of up to 8%.
Effect of Stirrup Spacing and Recycled Steel Wires on the Shear and Energy Dissipation of Pultruded GFRP Hybrid Beams
(Sage Publications Ltd, 2025) Ozkilic, Yasin Onuralp; Kalkan, Ilker; Aksoylu, Ceyhun; Madenci, Emrah; Umiye, Osman Ahmed; Althaqafi, Essam; Beskopylny, Alexey N.
The contribution of Recycled Steel Wires (RSW) to the shear strength and behavior of pultruded glass fiber reinforced polymer (P-GFRP) hybrid composite beams with reinforced concrete infill, denoted as P-GFRP beams, was investigated experimentally and analytically in the current study. A total of six specimens with varying RSW ratio and stirrup spacing of the reinforced concrete (RC) core and a fixed shear span-to-beam depth ratio were tested to failure. The addition of RSW to concrete was established to have greater contribution to the beam strength with increasing stirrup spacing, that is, decreasing transverse reinforcement ratio. The contribution of RSW to energy dissipation capacity was found to be more pronounced in the elastic range of beam response as compared to the inelastic range. The theoretical calculations indicated that the RC core prevented the P-GFRP encasement from complete failure due to shear-induced material rupture at the initial stages of loading. By maintaining their integrity, the reinforced concrete-filled box beams (RCFB) were able to resist loading until complete failure associated with flexure-induced material rupture and web compression buckling. A strut-and-tie model providing accurate strength estimates for P-GFRP beams was also proposed.
Citation - WoS: 6
Citation - Scopus: 6
Experimental, Theoretical and Digital Image Correlation Methods to Assess Bending Performance of RC Beams With Recycled Glass Powder Replacing Cement
(Nature Portfolio, 2025) Aksoylu, Ceyhun; Basaran, Bogachan; Karalar, Memduh; Zeybek, Ozer; Althaqafi, Essam; Beskopylny, Alexey N.; Ozkilic, Yasin Onuralp
This study investigates the use of Waste Glass Powder (WGP) as a proportional replacement for cement in sustainable concrete production. In addition, changes in the bending capacity of the Reinforced Concrete (RC) Beams were examined by adding WGP at different rates (0%, 10%, 20%, 30%) to RC Beams with different steel reinforcement ratios (rho s = 0.0077 i.e. Phi 8, rho s = 0.0121 i.e. Phi 10, rho s = 0.0174 i.e. Phi 12). To pursue this goal, 12 test specimens were evaluated and then confirmed to explore the bending productivity. The amount of longitudinal bar section area and WGP proportion were chosen as the key parameters. For this aim, experimental and analytical investigations were carried out by replacing cement with WGP in weight ratios of 10%, 20%, and 30% and considering three different longitudinal reinforcements (rho s = 0.0077 i.e. Phi 8, Phi 10, Phi 12). The test results showed that tension reinforcement section area and WGP proportion dimensions had dissimilar rupture and flexure effects on RC Beams. Furthermore, investigational tests are confirmed with the help of the Digital Imagining Method, and the image processing method was used to identify the cracks/microcracks in RC Beams. Consequently, it is observed that each WGP ratio in the concrete combination has dissimilar bending and rupture properties on the RC Beams for experimental tests-10% of partial replacement of cement. It was found that a WGP ratio of more than 10% can significantly reduce the bending capacity of RC Beams. When the experimental test beams were compared with the analytical results, it was observed that the experimental results and analytical calculations are in agreement.
Citation - WoS: 65
Citation - Scopus: 71
Flexural Behavior of Reinforced Concrete Beams Using Waste Marble Powder Towards Application of Sustainable Concrete
(Frontiers Media Sa, 2022) Karalar, Memduh; Özkılıç, Yasin Onuralp; Aksoylu, Ceyhun; Sabri, Mohanad Muayad Sabri; Beskopylny, Alexey N.; Stel'makh, Sergey A.; Shcherban, Evgenii M.
The performance of waste marble powder as a partial replacement for cement is examined with the aim to achieve more sustainable concrete. Pursuant to this goal, a total of 15 specimens were manufactured and then tested to examine the bending behavior. The effects of longitudinal reinforcement ratio and waste marble powder ratio were selected as variables. The experimental results showed that different proportions of tension reinforcement and waste marble powder had different crack and bending impacts on reinforced concrete beams. As the waste marble powder amount in the concrete mixture is increased from 0% to 40%, it was detected that the crack type changes from a shear crack from to a flexural crack as the amount of waste marble powder increases in the mixing ratio. The experimental findings revealed that the waste marble powder can be successfully used as 10% of the partial replacement of cement. Increasing the waste marble powder ratio by more than 10% can significantly decrease the capacity of the beams, especially when longitudinal reinforcement ratio is high. The influence of waste marble as partial replacement on the capacity decreases as the longitudinal reinforcement ratio decreases. Therefore, 10%-20% marble waste can be utilized as a replacement for cement when the longitudinal reinforcement ratio is close to the balanced ratio and more than 20% waste marble ratio should be avoided for any cases.
Highly Effective Injection Composites With Fly Ash and Microsilica for Soil Stabilization
(MDPI, 2025) Ozkilic, Yasin Onuralp; Beskopylny, Alexey N.; Aksoylu, Ceyhun; Stel'makh, Sergey A.; Shcherban', Evgenii M.; Madenci, Emrah; Kosykh, Alexey
Injection composites based on mineral binders are widely used for soil stabilization, using jet grouting technology to solve various geotechnical problems. Cement, which contains toxic components and worsens the ecology of the environment, is typically the main mineral component used to manufacture injection composites. Reducing cement consumption in the production of building materials is currently of great importance. This study developed highly effective, environmentally friendly injection composites for soil stabilization based on three mineral components: Portland cement, fly ash (FA), and microsilica (MS). FA was introduced into the composites as a partial Portland cement substitute, in amounts ranging from 5 to 50% in 5% increments. The properties of fresh and hardened composites, including the density, flow rate, water separation, compressive strength at 7 and 28 days, and the structure and phase composition of the composites, were studied. The inclusion of FA in the composition of composites contributes to a decrease in density by 16.9%, from 1.89 g/cm3 to 1.57 g/cm3, and cone spread by 9%, from 30.1 cm to 27.4 cm, and an increase in water bleeding by 91.4%, from 3.5% to 6.7%, respectively. Based on the results of the experimental studies, the most effective dosage of FA was determined, which amounted to 20%. An increase in compressive strength was recorded for composites at the age of 7 days of 8.3%, from 33.6 MPa to 36.4 MPa, and for compressive strength at the age of 28 days of 9.4%, from 41.3 MPa to 45.2 MPa, respectively. SEM and XRD analysis results show that including FA and MS promotes the formation of additional calcium hydrosilicates (CSH) and the development of a compact and organized composite structure. The developed composites with FA contents of up to 50% exhibit the required properties and can be used for their intended purpose in real-world construction for soil stabilization.
The Influence of Fiber-Form Waste Tire Aggregates on the Flexural Strength, Ductility, and Energy Dissipation of Pultruded GFRP-Rubberized Concrete Hybrid Beams
(MDPI, 2025) Ecemis, Ali Serdar; Karalar, Memduh; Beskopylny, Alexey N.; Stel'makh, Sergey A.; Shcherban, Evgenii M.; Aksoylu, Ceyhun; Ozkilic, Yasin Onuralp
This study investigates the effects of different proportions of waste rubber fiber aggregates on the flexural behavior of reinforced concrete beams. Beam specimens were prepared with different proportions (5%, 10%, and 15%) of waste rubber fiber aggregates, and composite beams formed with pultruded GFRP profiles were tested under vertical load. According to the results of this study, cube compressive strength, cylinder tensile strength, and beam flexural strength decreased by 27.5%, 50%, and 47.6%, respectively, with the use of a 15% waste rubber aggregate. As a result of the four-point bending tests performed on reinforced concrete beams, the maximum load-carrying capacity of the beams decreased significantly after increasing the waste rubber aggregate ratio to 10% and 15%. However, a general improvement in the ductility of the beams was observed. One of the main results of this study is that when the waste rubber aggregate content is 5%, the best balance between strength and ductility is achieved, and the performance closest to the reference beams is obtained. The tests also revealed that the & Oslash;10-5% specimen exhibited higher performance in terms of both load-carrying capacity and yield stiffness. On the other hand, although the 15% waste rubber aggregate ratio caused a decrease in the maximum load-carrying capacity. along with an increase in the diameter of the tensile reinforcement, this decrease was quite low. Finally, an overall decrease in energy consumption capacity was observed with increasing waste rubber aggregate content in all test beams. This can be attributed to the acceleration of shear damage in the beam and the shrinkage of the area under the load-displacement curve as the amount of waste increases. Additionally, SEM analyses were conducted in order to investigate the microstructural behavior of the rubberized concrete. This study has shown that the use of waste rubber aggregates can be environmentally and economically beneficial, especially at the 5% level.
Citation - WoS: 26
Citation - Scopus: 31
Lightweight Expanded-Clay Fiber Concrete With Improved Characteristics Reinforced With Short Natural Fibers
(Elsevier, 2023) Özkılıç, Yasin Onuralp; Beskopylny, Alexey N.; Stelmakh, Sergey A.; Shcherban, Evgenii M.; Mailyan, Levon R.; Meskhi, Besarion; Chernilnik, Andrei
Weight reduction should be accompanied by maintaining the strength and quality of materials utilized in construction. One of the comprehensive solutions to this problem can be the utilization of dispersed fiber reinforcement of concrete with plant fibers of various origins, which led to the sustainable production of concrete. Knowledge regarding the behavior of lightweight concrete with plant fibers is currently rather limited. Therefore, the primary aim of this article was to study the possibility of creating lightweight expanded-clay fiber concrete (ECFC) with improved characteristics, considering the dispersed reinforcement of this concrete with coconut (CF) and sisal (SF) fibers. Test methods and scanning electron microscopy (SEM) analyses were used for the structural study. Dispersed reinforcement of lightweight expanded clay concrete with fibers of organic origin has a positive effect on its mechanical characteristics. The optimal content of expanded clay in lightweight concrete was obtained in terms of the ratio of strength and density. The content of CF and SF, which provides the highest increases in compressive and flexural strength, was 2% of the mass of cement. It was found that SF in lightweight ECFC performs better and provides greater strength gains than CF. The compressive strength of ECFC with CF increased by 8.9%, the bending strength by 16.1%, and with SF by 10.1% and 18.3%, respectively, compared to the fiber-free composite. The coefficient of the constructive quality values of lightweight ECFC is up to 16% higher with CF and up to 18% with SF than a concrete composite without fibers. Moreover, formulas were derived to predict the compressive of ECFC with and without CF and SF.
Citation - WoS: 6
Citation - Scopus: 7
Modeling and Calculation of Improved Centrifuged Reinforced Concrete Columns With Variotropic Structure
(MDPI, 2023) Stel'makh, Sergey A.; Shcherban', Evgenii M.; Beskopylny, Alexey N.; Mailyan, Levon R.; Veremeenko, Andrey; Shilov, Aleksandr V.; Ananova, Oxana; Aksoylu, Ceyhun
The use of vibro-centrifugation technology allows the manufacture of variotropic structures that are inhomogeneous in the annular section and have different characteristics along the section thickness. Hardening of the outer layers allows the structure to better resist bending conditions, however, the behavior of the variotropic column under central and eccentric compression remains unexplored. This article considers the problem of compression of hollow columns made of homogeneous concrete that is non-uniform in the annular section (variotropic), and is reinforced with steel reinforcing bars at different values of the load application eccentricity. Variotropic concrete obtained by vibro-centrifugation technology has a stronger outer part and a less durable inner part. The strength of a homogeneous column corresponds to the strength of the middle part of variotropic concrete. The problem was solved numerically in the ANSYS environment for a vertical column rigidly clamped at the bottom edge and loaded with eccentricity at the top edge. Three types of eccentricity are considered; e/r = 0, 0.16 and 0.32 (respectively 0 mm, 0.24 mm and 48 mm). The results of the solution in the form of stress fields, deformations and a pattern of crack development in a spatial setting are obtained. The results showed that for central compression, a homogeneous column has a better bearing capacity of 3.6% than a variotropic one. With the values of eccentricity e/r = 0.16 and 0.32, the variotropic column has a higher bearing capacity (by 5.5% and 6.2%) than the homogeneous one and better resists the development of cracks. The significance of the study lies in the practical application of the proposed approach, developed on a research basis, for non-trivial and complicated operating conditions of columns. This study influences the development of reinforced concrete structures and applies scientific findings to engineering practice.
Citation - WoS: 50
Citation - Scopus: 55
Normal-Weight Concrete With Improved Stress-Strain Characteristics Reinforced With Dispersed Coconut Fibers
(MDPI, 2022) Shcherban, Evgenii M.; Stel'makh, Sergey A.; Beskopylny, Alexey N.; Mailyan, Levon R.; Meskhi, Besarion; Shilov, Alexandr A.; Chernil'nik, Andrei; Aksoylu, Ceyhun
According to the sustainable development concept, it is necessary to solve the issue of replacing fiber from synthetic materials with natural, environmentally friendly, and cheap-to-manufacture renewable resources and agricultural waste. Concrete is the primary material for which fibers are intended. Therefore, the use of vegetable waste in concrete is an essential and urgent task. Coconut fiber has attracted attention in this matter, which is a by-product of the processing of coconuts and makes it relevant. This work aims to investigate the experimental base for the strength properties of dispersed fiber-reinforced concrete with coconut fibers, as well as the influence of the fiber percentage on the mechanical, physical, and deformation characteristics. The samples were made of concrete with a compressive strength at 28 days from 40 to 50 MPa. The main mechanical characteristics such as strength in compression (cubic and prismatic) and tension (axial and bending), as well as the material's compressive and tensile strains, were investigated. The percentage of reinforcement with coconut fibers was taken in the range of 0% to 2.5% with an increment of 0.25 wt.%. Tests were carried out 28 days after the manufacture. The microstructure of the resulting compositions was investigating using the electron microscopy method. The most rational percentage of coconut fibers was obtained at 1.75%. The increase in mechanical indicators was 24% and 26% for compression and axial compression, respectively, and 42% and 43% for tensile bending and axial tension, respectively. The ultimate strains in compression were raised by 46% and in tension by 51%. The elastic modulus was increased by 16%.
Optimization of Concrete with Human Hair Using Experimental Study and Artificial Neural Network via Response Surface Methodology and Anova
(Nature Portfolio, 2025) Yildizel, Sadik Alper; Karalar, Memduh; Aksoylu, Ceyhun; Althaqafi, Essam; Beskopylny, Alexey N.; Stel'makh, Sergey A.; Ozkilic, Yasin Onuralp
The increasing demand for sustainable construction materials has prompted the investigation of non-biodegradable waste, such as human hair (HH), for concrete reinforcement. This study seeks to evaluate the impact of HH fiber on the fresh, physical, and mechanical characteristics of concrete. HH was incorporated in varying proportions (1-5% by weight of cement), along with modifications in cement content, to ascertain optimal performance conditions. An extensive experimental program was executed, succeeded by the utilization of Artificial Neural Networks (ANN) to formulate predictive models for compressive strength (CS), flexural strength (FS), and splitting tensile strength (STS). Furthermore, Response Surface Methodology (RSM) and Analysis of Variance (ANOVA) were utilized to identify statistically significant factors and optimize the mix design. The findings indicated that the mechanical performance of concrete enhanced with HH inclusion up to 3%, after which a deterioration ensued, presumably due to inadequate dispersion and workability challenges. The ANN models precisely predicted mechanical outcomes, while the RSM-derived models demonstrated strong correlations, with R2 values of 0.9434, 0.9365, and 0.9311 for CS, FS, and STS, respectively. ANOVA confirmed the significance of model inputs with p-values below 0.05. Furthermore, SEM, EDX, and XRD analyses validated the integration of HH into the concrete matrix and substantiated the observed mechanical properties. This study confirms the feasibility of HH as a sustainable fiber in concrete, enhancing critical performance metrics when applied at optimal dosages. The amalgamation of ANN, RSM, and ANOVA offers a thorough methodology for optimizing innovative concrete composites and clarifying the mechanisms underlying performance enhancement.
Citation - WoS: 4
Citation - Scopus: 3
Performance Assessment of a Novel Green Concrete Using Coffee Grounds Biochar Waste
(Mdpi, 2024) Beskopylny, Alexey N.; Stel'makh, Sergey A.; Shcherban', Evgenii M.; Ananova, Oxana; Chernil'nik, Andrei; El'shaeva, Diana; Pogrebnyak, Anastasia
An actual scientific problem in current concrete science is poor knowledge of the problem of modifying concrete with plant waste. At the same time, plant waste benefits from other types of waste because it is a recycled raw material. A promising technological approach to modifying concrete with plant waste is the introduction of components based on the processing of coffee production waste into concrete. This study aims to investigate the use of biochar additives from spent coffee grounds (biochar spent coffee grounds-BSCG) in the technology of cement composites and to identify rational formulations. A biochar-modifying additive was produced from waste coffee grounds by heat treatment of these wastes and additional mechanical grinding after pyrolysis. The phase composition of the manufactured BSCG additive was determined, which is characterized by the presence of phases such as quartz, cristobalite, and amorphous carbon. The results showed that the use of BSCG increases the water demand for cement pastes and reduces the cone slump of concrete mixtures. Rational dosages of BSCG have been determined to improve the properties of cement pastes and concrete. As a result of the tests, it was determined that the ideal situation is for the BSCG ratio to be at a maximum of 8% in the concrete and not to exceed this rate. For cement pastes, the most effective BSCG content was 3% for concrete (3%-4%). The compressive and flexural strengths of the cement pastes were 6.06% and 6.32%, respectively. Concrete's compressive strength increased by 5.85%, and water absorption decreased by 6.58%. The obtained results prove the feasibility of using BSCG in cement composite technology to reduce cement consumption and solve the environmental problem of recycling plant waste.
Citation - WoS: 14
Citation - Scopus: 18
Physical, Mechanical and Structural Characteristics of Sulfur Concrete With Bitumen Modified Sulfur and Fly Ash
(MDPI, 2023) Stel'makh, Sergey A.; Shcherban', Evgenii M.; Beskopylny, Alexey N.; Mailyan, Levon R.; Meskhi, Besarion; Shilov, Alexandr A.; Evtushenko, Alexandr; Aksoylu, Ceyhun
Industrial waste usage in the technology of construction materials is currently in a relevant and promising direction. Materials made of industrial waste have a lower cost and are highly environmentally friendly. The objective of this study is to develop effective compositions of sulfur concrete based on the maximum possible number of various wastes of the local industry for this and to investigate the characteristics of this composite. Test samples of sulfur concrete were made from sulfur, fly ash, mineral aggregates and bitumen additive. The dosages of fly ash, sand and bitumen varied, while the content of sulfur and crushed stone remained constant. The following main characteristics of sulfur concrete were determined: density; compressive strength; and water absorption. Tests of sulfur concrete were carried out after 1 day and 28 days of hardening. The best values of compressive strength (24.8 MPa) and water absorption (0.9%) were recorded for the composition of sulfur concrete at the age of 28 days with the following content of components: sulfur-25%, modified with 4% bitumen of its mass; fly ash-10%; crushed stone-40%; and sand-25%. The optimal composition of modified sulfur concrete showed compressive strength up to 78% more and water absorption up to 53% less than the control composition. The characteristics of the sulfur concrete samples after 28 days of hardening differ slightly from the values after 1 day of hardening (up to 1.8%). An analysis of the structure confirmed the effectiveness of the developed composition of sulfur concrete in comparison with the control.
Citation - WoS: 2
Citation - Scopus: 2
Porosity Analysis and Thermal Conductivity Prediction of Non-Autoclaved Aerated Concrete Using Convolutional Neural Network and Numerical Modeling
(MDPI, 2025) Beskopylny, Alexey N.; Shcherban', Evgenii M.; Stel'makh, Sergey A.; Elshaeva, Diana; Chernil'nik, Andrei; Razveeva, Irina; Ozkilic, Yasin Onuralp
Currently, the visual study of the structure of building materials and products is gradually supplemented by intelligent algorithms based on computer vision technologies. These algorithms are powerful tools for the visual diagnostic analysis of materials and are of great importance in analyzing the quality of production processes and predicting their mechanical properties. This paper considers the process of analyzing the visual structure of non-autoclaved aerated concrete products, namely their porosity, using the YOLOv11 convolutional neural network, with a subsequent prediction of one of the most important properties-thermal conductivity. The object of this study is a database of images of aerated concrete samples obtained under laboratory conditions and under the same photography conditions, supplemented by using the author's augmentation algorithm (up to 100 photographs). The results of the porosity analysis, obtained in the form of a log-normal distribution of pore sizes, show that the developed computer vision model has a high accuracy of analyzing the porous structure of the material under study: Precision = 0.86 and Recall = 0.88 for detection; precision = 0.86 and recall = 0.91 for segmentation. The Hellinger and Kolmogorov-Smirnov statistical criteria, for determining the belonging of the real distribution and the one obtained using the intelligent algorithm to the same general population show high significance. Subsequent modeling of the material using the ANSYS 2024 R2 Material Designer module, taking into account the stochastic nature of the pore size, allowed us to predict the main characteristics-thermal conductivity and density. Comparison of the predicted results with real data showed an error less than 7%.
Citation - WoS: 2
Citation - Scopus: 2
Properties and Structure of Functional Concrete Mixtures Modified With River Shell Powder
(C Ej Publishing Group, 2024) Stel'makh, Sergey A.; Shcherban, Evgenii M.; Beskopylny, Alexey N.; Hiep, Nguyen Quang; Song, Yamin; Elshaeva, Diana; Chernil'nik, Andrei; Aksoylu, Ceyhun
The recycling of the aquaculture waste into clam powder reduces solid emissions and natural resources, which is important for Portland cement production. This study determines the feasibility of using recycled river shell waste as a partial replacement for cement in concrete technology. The study used normative methods and optical microscopy; the properties of cement mixtures, such as normal consistency, setting time (ST), compressive and flexural strength, were studied. Research findings have shown that the inclusion of river shell powder (RSP) in cement mixtures can reduce water demand and a decrease in setting time with increasing RSP content. It was also found that the strength of the cement mixture can be maintained with an RSP content of up to 10%. The following properties of the concrete were determined: workability, compressive strength (CS), and water absorption. Using RSP as a partial replacement for cement has been proven to elevate the slump of the fresh concrete cone. CS is maintained at a level comparable to the control composition, with an RSP content of no more than 8%, and water-absorbing is reduced by 7.31%. This study created new compositions, and the links between the ingredients, properties, and structure of cement composites modified with river shell powder were investigated. Additionally, the properties of the structure-formation process of these modified composites were studied.
Citation - WoS: 13
Citation - Scopus: 15
Shear Performance in Reinforced Concrete Beams With Partial Aggregate Substitution Using Waste Glass: a Comparative Analysis Via Digital Imaging Processing and a Theoretical Approach
(AMER CHEMICAL SOC, 2024) Zeybek, Özer; Basaran, Bogachan; Aksoylu, Ceyhun; Karalar, Memduh; Althaqafi, Essam; Beskopylny, Alexey N.; Stel'makh, Sergey A.
The usage of waste glass aggregate (WGA) associated with the replacement of fine aggregate (FA) and coarse aggregate (CA) is observed to reduce the number of raw materials for sustainable concrete. For this aim, a total of 15 beams were produced, and then investigational experiments were implemented to observe the shear performances. The stirrup spacing and WGA proportion were chosen as the main parameters. FA and CA were exchanged with WGA with weight proportions of 0, 10, and 20%. The experimental investigation results showed that changing stirrup spacing and WGA proportion affected the fracture and shear properties of reinforced-concrete-beams (R-C-Bs). Furthermore, the findings of the test results revealed that the proportion of WGA could be efficiently consumed as 20% of the partial replacement of FA. With the addition of FA to the mixture, the load carrying capacity of R-C-Bs increases. On the other hand, increasing the WGA ratio by more than 10% using CA, together with increasing the stirrup spacing, can significantly reduce the capacity of R-C-Bs. It was observed that the calculated shear strengths of R-C-Bs with inadequate stirrup spacing, based on ACI 318 and EC2 design codes, can be up to 52 and 79% higher than the experimental results for R-C-Bs containing coarse glass aggregate and 21 and 56% higher for R-C-Bs containing fine glass aggregate, respectively. Additionally, an image processing method was applied to describe the damages/microdamages in R-C-Bs. At that point, the findings obtained from the experimental part of the study were confirmed by the results of the image processing method. Although the strains obtained with the image processing method are reliable, it has not been determined exactly where the crack will occur due to the very sudden development of the shear crack at the moment of beam failure.
Sustainable Concrete with Waste Tire Rubber and Recycled Steel Fibers: Experimental Insights and Hybrid PINN-CatBoost Prediction
(MDPI, 2025) Ecemis, Ali Serdar; Yildizel, Sadik Alper; Beskopylny, Alexey N.; Stel'makh, Sergey A.; Shcherban', Evgenii M.; Aksoylu, Ceyhun; Ozkilic, Yasin Onuralp
The growing environmental concern over waste tire accumulation necessitates innovative recycling strategies in construction materials. Therefore, this study aims to develop and evaluate sustainable concrete by integrating waste tire rubber (WTR) aggregates of different sizes and recycled waste tire steel fibers (WTSFs), assessing their combined effects on the mechanical and microstructural performance of concrete through experimental and analytical approaches. WTR aggregates, consisting of fine (0-4 mm), small coarse (5-8 mm), and large coarse (11-22 mm) particles, were used at substitution rates of 0-20%; WTSF was used at volumetric dosages of 0-2%, resulting in a total of 40 mixtures. Mechanical performance was evaluated using density and pressure resistance tests, while microstructural properties were assessed using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). The findings indicate systematic decreases in density and compressive strength with increasing WTR ratio; the average strength losses were approximately 12%, 20%, and 31% at 5%, 10%, and 20% for WTR substitution, respectively. Among the WTR types, the most negative effect occurred in fine particles (FWTR), while the least negative effect occurred in coarse particles (LCWTR). The addition of WTSF compensated for losses at low/medium dosages (0.5-1.0%) and increased strength by 2-10%. However, high dosages (2.0%) reduced strength by 20-40% due to workability issues, fiber clumping, and void formation. The highest strength was achieved in the 5LCWTR-1WTSF mixture at 36.98 MPa (approximate to 6% increase compared to the reference/control concrete), while the lowest strength was measured at 16.72 MPa in the 20FWTR-2WTSF mixture (approximate to 52% decrease compared to the reference/control). A strong positive correlation was found between density and strength (r, Pearson correlation coefficient, approximate to 0.77). SEM and EDX analyses confirmed the weak matrix-rubber interface and the crack-bridging effect of steel fibers in mixtures containing fine WTR. Additionally, a hybrid prediction model combining physics-informed neural networks (PINNs) and CatBoost, supported by data augmentation strategies, accurately estimated compressive strength. Overall, the results highlight that optimized integration of WTR and WTSF enables sustainable concrete production with acceptable mechanical and microstructural performance.
Citation - WoS: 14
Citation - Scopus: 17
Utilizing Recycled Glass Powder in Reinforced Concrete Beams: Comparison of Shear Performance
(Nature Portfolio, 2025) Karalar, Memduh; Basaran, Bogachan; Aksoylu, Ceyhun; Zeybek, Ozer; Althaqafi, Essam; Beskopylny, Alexey N.; Ozkilic, Yasin Onuralp
In this research, the effect of using waste glass powder (WGP) as a partial replacement for cement on the flexural behavior of reinforced-concrete-beams (R-C-Bs) was investigated. For this aim, a total of 9 specimens were produced, and investigational experimentations were conducted to evaluate the flexural performances of R-C-Bs. Subsequently, the cement was partially replaced with WGP with weight percentages of 0%, 10%, 20% and 30%. Furthermore, the influence of stirrup spacing (SS) in the longitudinal reinforcement on productivity was also examined. The results presented indicate that the efficient WGP percentage might be considered as 10% of the partial replacement of cement. Increasing the WGP percentage within the cement by more than 10% may considerably reduce the ability of the R-C-Bs, noticeably when the lengthwise reinforcement proportion is high. Additionally, the experimental shear strengths of R-C-Bs attained from the flexural tests were compared with the shear capacities estimated using Eurocode 2 and ACI 318 - 19 regulations. It was concluded that the shear capacities calculated with ACI318-19 are much lower than the values calculated with EC2. Furthermore, it may be observed that ACI318-19 calculates the shear capacities of R-C-Bs to be 15-51% higher than those of the experimental results. Furthermore, the Digital Image Correlation (DIC) was used to study the flexural cracks/micro-cracks in R-C-Bs. Comparisons indicate that DIC has similar deformations and fracture properties for the R-C-Bs as the experimental tests. Finally, it was considered that the optimum consumption quantities determined by the results of the present research would be a guide for future investigation.