75504 2712-8172 Magazine of Civil Engineering 18 7 139 2025
RAR RUS 13901-13901 Department of Structures and Water Resources Engineering, Faculty of Engineering, University of Kufa Alkraidi Afrah afrraha.alkridy@uokufa.edu.iq
Najaf, Iraq
 Department of Civil Engineering, Faculty of Engineering, University of Kufa Aljazaari Rasha rashaa.aljazaari@uokufa.edu.iq
Najaf, Iraq
 Department of Structures and Water Resources Engineering, Faculty of Engineering, University of Kufa Aldikheeli Mohammed mohammedr.aldikheeli@uokufa.edu.iq
Najaf, Iraq
 0000-0001-6244-7965 University of Kufa Alasadi Layth Abdulrasool laitha.alasadi@uokufa.edu.iq
Al Najaf, Iraq
 Department of Structures and Water Resources Engineering, Faculty of Engineering, University of Kufa Almusawi Thaaer thaaer.almusawi@uokufa.edu.iq
Najaf, Iraq
 Department of Civil Engineering, Faculty of Engineering, University of Kufa Alatiya Qusay qusay.alatiya@uokufa.edu.iq
Najaf, Iraq
 Mechanical properties of concrete made with waste fine and coarse ceramic aggregates This study aims to produce a new type of waste aggregate concrete by using fine and coarse waste ceramic as aggregate; the waste ceramic used in this study was in 2 types: red ceramic, which has a red color and is produced from waste ceramic tiles, and white ceramic, which produced from the waste of tableware. Replacing ordinary fine and coarse aggregate with a ceramic waste aggregate improved the mechanical properties of concrete, compressive, tensile, flexural strength, and modulus of elasticity of normal concrete by using waste ceramic as aggregates. 20, 40, 60, 80, and 100 % replacement by weight of aggregates are studied. Total replacement of normal aggregate with white ceramic aggregates led to an increase in compressive strength from 42.2 to 52.1 MPa; tensile strength also increased from 2.9 to 4.8 MPa, flexural strength increased from 4.3 to 8.7 MPa, and static modulus of elasticity has risen from 25.6 to 32.8 GPa.The mechanical properties of red ceramic increased until 60 % replacement; a slight decrement in mechanical properties was found after 60 % replacement. Studies show that waste white ceramic has better mechanical properties than red clay ceramic. 10.34910/MCE.139.1 69 waste aggregate waste fine coarse ceramic compressive tensile flexural strength modulus of elasticity https://engstroy.spbstu.ru/article/2025.139.1/
RAR RUS 13902-13902 24332324000 0000-0003-3714-2996 Peter the Great St. Petersburg Polytechnic University Mostovykh Pavel mostovykh_ps@spbstu.ru
St. Peterburg, Russian Federation
 Peter the Great St. Petersburg Polytechnic University Dontsova Anna anne.dontsoova@gmail.com
29 Politechnicheskaya St., St. Petersburg, 195251, Russia
 57189345350 0000-0002-8380-0067 Peter the Great St. Petersburg Polytechnic University Koriakovtseva (Musorina) Tatiana
29 Politechnicheskaya St., St. Petersburg, 195251, Russia
 Peter the Great Saint Petersburg Polytechnic University Stolyarov Oleg oleg.stolyarov@rambler.ru
Polytechnicheskay, 29
 Stress relaxation behavior of glass and carbon fiber reinforcements in prestressed concrete applications High-performance fibrous materials offer advantages such as high strength and low weight, making them promising for use in prestressed concrete. This work investigates the stress relaxation behavior of glass and carbon fiber reinforcements. Stress relaxation tests were conducted at load levels ranging from 10 % to 40 % of the materials’ tensile strength. A mathematical model was developed to describe this behavior, and the model parameters were determined. The stress relaxation of the fiber reinforcements was simulated and the resulting prestress loss was compared with that of traditional steel reinforcement. It was found that stress relaxation is more pronounced in glass and carbon fiber reinforcements than in steel. It was shown that the observed stress loss is primarily caused by the slippage of the fibrous reinforcement. Based on the findings, practical recommendations are provided for the application of these results in prestressed concrete design. 10.34910/MCE.139.2 624.012.45:539.376 prestressed concrete stress relaxation fiber reinforcement roving viscoelasticity modeling https://engstroy.spbstu.ru/article/2025.139.2/
RAR RUS 13903-13903 0000-0002-3565-5942 Badji Mokhtar Annaba University Otmani-Benmehidi Nadia nadia.otmani@univ-annaba.dz
Annaba, Algérie
 0009-0000-9772-1194 Badji Mokhtar Annaba University Boudjadja Marwa boudjadjamarwa1@gmail.com
Annaba, Algérie
 0000-0001-8316-1843 National Higher School of Technology and Engineering, Department of Process and Energy Engineering Otmani Abdessalem a.otmani@ensti-annaba.dz
Annaba, Algeria
 Behavior of white wood at elevated temperatures: insights from numerical and experimental studies This study investigates the fire behavior of white wood, a commercially dominant softwood in Algerian construction (cf. Picea abies). Using a combined experimental and numerical approach, the thermo-mechanical degradation of 8×8×32 cm specimens was analyzed. Experiments involved heating samples in an electric oven at 200 °C and 300 °C, with complementary simulations performed using the SAFIR software. The results confirm that elevated temperatures induce significant mass loss and a pronounced thermal gradient, with the core lagging behind the surface. This thermal degradation directly compromises mechanical properties, notably stiffness. Furthermore, the study establishes a clear link between physical phenomena – charring, smoke emission, mass loss – and the underlying degradation mechanisms. A critical finding was the failure of adhesive bonds at high temperatures, revealing a key vulnerability in assembled wooden structures under fire conditions. These findings provide essential data for modeling the fire performance of a vital local material, thereby informing safer regional construction practices. 10.34910/MCE.139.3 69 wood specimen high temperature oven properties white wood SAFIR https://engstroy.spbstu.ru/article/2025.139.3/
RAR RUS 13904-13904 Kalashnikov Izhevsk State Technical University Alexandrov Alexandr aleksandrov2332@yandex.ru
Izhevsk, Russian Federation
 7006888927 0000-0002-2754-3967 Kalashnikov Izhevsk State Technical University Yakovlev Grigorij gyakov@istu.ru
Izhevsk, Russia
 0000-0002-3331-9443 Moscow State University of Civil Engineering (MGSU) National Research University Buryanov Aleksandr rga-service@mail.ru
Moscow, Russia
 Kalashnikov Izhevsk State Technical University Bekmansurov Marat bekmansurov2@mail.ru
Izhevsk, Russian Federation
 National Research Tomsk Polytechnic University Martyushev Nikita martjushev@tpu.ru
Tomsk, Russian Federation
 M-6585-2013 6508103761 0000-0002-1196-8004 Peter the Great Saint Petersburg Polytechnic University Vatin Nikolai vatin@mail.ru
Polytechnicheskay, 29
 57189716281 0000-0003-3287-3298 Moscow State University of Civil Engineering Karlina Antonina karlinat@mail.ru
Moscow, Russia
 Use of fluorohydride as a binder for stabilization of weak soils in road construction In the conditions of growing attention to resource saving and environmental safety in road construction, the search for new binding materials for soil stabilisation is topical. This work is devoted to the study of the possibility of using fluoranhydride, a waste product of hydrofluoric acid production, as a binder for road base stabilisation. The object of the study is a composite material based on fluoranhydride, clay, and activator – sodium phosphate solution. The influence of fluorohydride activation on the physical and mechanical characteristics of the composite, including compressive strength, water absorption, and softening coefficient, has been studied. Fluoranhydrite is activated by 3 % sodium phosphate solution, which increases the strength of the obtained material. The physical and mechanical properties of composites consisting of fluorangydrite, loam, and sodium phosphate have been investigated. X-ray phase and IR spectral analyses were carried out, as well as scanning electron microscopy and energy dispersive X-ray spectroscopy. The results show that the optimum ratio of loam to fluorohydrite is 40/60 as it provides the highest economic efficiency. The compressive strength of this composition at the age of 28 days is also favourable: 8.9 MPa in the dry state and 7.3 MPa in the wet state, while the water absorption is 6.82 % and the softening coefficient is 0.82. The study confirms that fluorohydrite can be used as a binder to stabilize weak soils, which helps to reduce the cost of works and reuse waste materials, reducing the environmental load. 10.34910/MCE.139.4 691.3 soil stabilization strengthening fluoroanhydrite IR spectroscopy differential thermal analysis microstructure https://engstroy.spbstu.ru/article/2025.139.4/
RAR RUS 13905-13905 0009-0000-7574-9313 Islamic Azad University, Lahijan Branch Mohammadalizadeh Saeid saeidmhmdalizadeh74@gmail.com
Lahijan, Iran
 Islamic Azad University, Lahijan Branch, Department of Civil Engineering Yasaei Ali aliyasaei5@gmail.com
Lahijan, Iran
 0000-0001-8054-8209 Islamic Azad University, Lahijan Branch, Department of Civil Engineering Mardookhpour Alireza AR.mardookhpour@iau.ac.ir
Lahijan, Iran
 Flow turbulence conditions and sensitivity of bucket-type spillway geometry parameters in energy dissipation Energy dissipation downstream of dams is considered one of the important issues in these structures. Various structures have been employed to perform this function. Among them, bucket-type spillways are of great importance, where the outflow jet from these structures faces complex issues, including jet diffusion and downstream erosion. With the hardware and software advancement of numerical simulation systems, the evaluation of this phenomenon is possible at a lower cost compared to laboratory conditions. In this research, using FLOW-3D software and the RNG turbulence model, the effects of various geometric and hydraulic parameters related to the bucket-type spillway on the outflow jet have been investigated. The results of the RNG turbulence model show better agreement with laboratory results compared to the (k-ε) turbulence model. The relative error in energy reduction between laboratory results and numerical model results is less than 5 %, and the error related to maximum jump length is less than 7 %. The changes in spillway geometry include changes in the spillway angle from 52 to 32 ° and changes in the spillway arc radius from 12 to 19 cm. 10.34910/MCE.139.5 624.12 bucket spillway energy dissipation throw length throw height throw angle RNG turbulence model (k-ε) turbulence model Flow-3D software https://engstroy.spbstu.ru/article/2025.139.5/
RAR RUS 13906-13906 6506150284 0000-0003-1139-3164 Moscow State University of Civil Engineering (National Research University) Sainov Mikhail mp_sainov@mail.ru
Moscow, Russia
 National Research University “Moscow Power Engineering Institute” Zuzov Alexey zuzuv3@yandex.ru
Moscow, Russian Federation
 Variation of stress-strain state of rockfill dam affected by creeping Rockfill is subject to creeping and this phenomenon has negative consequences for rockfill dam stress-strain state (SSS). Recently, rockfill creeping attracts more and more attention in China where a great number of embankment dams are constructed. Chinese scientists fulfilled tests of rockfill in stabilometers. However, for SSS numerical modeling, there are used other empirical rheological models whose parameters are determined by the method of SSS back analysis of existing rockfill dams. For studying the effect of creeping on rockfill dam SSS, the authors fulfilled back analysis for Tianshengqiao-I dam in China. Modeling the dam SSS was carried out with the aid of software package MIDAS. Two analyses were performed: without consideration of creeping and with consideration of it. Mohr–Coulomb model was used for description of rockfill deformation. For consideration of creeping, it was added by Maxwell–Kelvin rheological model. Reliability of SSS modeling was provided by selection of soil model parameters from condition of approximate correspondence between design and field displacements. Comparison of two design alternatives of analysis permitted making conclusions on the role of rockfill creeping in formation of the dam SSS. There was determined the share of displacements reached during construction due to time-dependent component of rockfill deformation. For settlements, it was amounted to approximately 20–30 %, and for horizontal displacements, it was higher. Creeping affects the character of settlement distribution in a complicated way. This is related to the fact that it causes growth of deformation of two types: shear deformations toward the downstream side and deformations of lateral expansion. In the lower part of the dam, deformations of lateral expansion prevail and in the upper part – share deformations. Such character of displacements may affect reinforced concrete face. Effect of creeping on rockfill stress state is not great and it is mainly related to rather small increase of tangent stresses. 10.34910/MCE.139.6 626.01 concrete faced rockfill dam stress-strain state creep numerical analysis rheological model long-term deformation settlement displacement https://engstroy.spbstu.ru/article/2025.139.6/
RAR RUS 13907-13907 0000-0002-6113-1237 Universiti Malaysia Pahang Al-Sultan Abdullah Shen Ng Jun jshenng98@gmail.com
Pekan, Pahang, Malaysia
 49361423900 0000-0002-2700-236X Universiti Malaysia Pahang Hasan Muzamir muzamir@ump.edu.my
Pahang, Malaysia
 Universiti Malaysia Pahang Al-Sultan Abdullah Er Yap Wan muzamir@umpsa.edu.my
Pahang, Malaysia
 0000-0002-7160-3015 Khulna University of Engineering & Technology Hoque Md. Ikramul ikramul3300@becm.kuet.ac.bd
Khulna, Bangladesh
 Advancing geotechnical engineering via sustainable biomass-based soil stabilization This research investigates the potential influence of mixing biomass resources, cow bone ash, in various percentages into the untreated kaolinitic soil in altering the geotechnical parameters. The nature of clayey soil frequently triggers the prevailing issues, such as uneven settlement, insufficient soil-bearing capacity, and abnormal compressibility coefficient. Several fundamental laboratory approaches were deployed to obtain information on grain size distribution, consistency limits, proctor behaviors, and specific gravity. The optimum moisture content of kaolin stabilized with cow bone ash was discovered at 6 %, and this value was utilized for the assessment of unconfined compression data. The examination of shear strength parameters was implemented via the fabrication of a cylindrical sample, dimensioned at 38 mm in diameter and 76 mm in height. The kaolin samples were altered using 3 %, 6 %, 9 %, and 12 % of cow bone ash content, and cured for periods of 7 and 14 days, respectively. The discoveries revealed that associating all portions of cow bone ash enhanced the kaolin shear strength significantly, ranging from 81.15 % to 578.10 %. The accuracy was verified by the utilization of the correlation technique, where all the curing periods of the samples possess a coefficient of determination greater than 0.9. Furthermore, the establishment of cost-analysis calculation generates a thorough framework for optimizing the total cost of stabilization, with the efficiency reaching 49.56 %. In short, using cow bone ash in soil stabilization resulted in positive implications that advance the technology of the geotechnical industry, proposing a promising development practice via the application of sustainable material. 10.34910/MCE.139.7 624 cow bone soil stabilization sustainability soil-bearing capacity kaolin clay https://engstroy.spbstu.ru/article/2025.139.7/
RAR RUS 13908-13908 0009-0000-0813-8133 Kuban State Technological University Abuizeih Yousef Q.Y. yousef.qasem1993@gmail.com
Krasnodar, Russian Federation
 57205126163 0000-0001-8235-2314 Kuban State Technological University Tamov Murat murat.tamov@gmail.com
Krasnodar, Russia
 Structural behavior of ultra-high performance concrete beams with different rebar and fiber reinforcement ratios This experimental study comprehensively analyzes the flexural performance of ultra-high performance concrete (UHPC) beams with combined rebar and fiber reinforcement. The study examines the synergistic effects of longitudinal reinforcement ratio  (varying from 0.31 to 5.13 %), steel fiber content (0–2 % by volume), and fiber geometry (comparing straight and wavy shapes) through testing of seventeen beam specimens under four-point bending conditions. Results demonstrate that steel fiber incorporation significantly enhances structural performance by improving crack control, with maximum crack widths remaining below 0.25 mm at service load levels (65–70 % of ultimate capacity). The benefits of fiber reinforcement show strong dependence on longitudinal rebar reinforcement ratio, with maximum strength improvements reaching 47 % for beams containing 2 % fibers at the lowest reinforcement ratio (0.31 %). Comparative analysis reveals the superior performance of wavy fibers, which provide up to 25 % greater strength enhancement compared to straight fibers in lightly reinforced specimens. The study identifies two distinct failure modes: abrupt failure after crack localization in lightly reinforced beams ( ≤ ≤ 0.87 %) versus gradual strength gain at post-localization stage in highly reinforced specimens ( ≥ ≥ 2.56 %). Fiber effectiveness diminishes significantly in highly reinforced beams due to rebar dominance and fiber distribution challenges in congested tensile zones. These findings provide quantitative evidence for optimizing fiber-rebar combinations in UHPC design, particularly highlighting the importance of fiber geometry selection and dispersion quality. The research establishes clear relationships between reinforcement parameters and structural performance, offering practical guidance for engineers while identifying key areas for future investigation, including advanced fiber dispersion techniques and hybrid reinforcement strategies for improved structural efficiency. 10.34910/MCE.139.8 69.07 ultra-high performance concrete steel fibers flexural behavior crack control hybrid reinforcement https://engstroy.spbstu.ru/article/2025.139.8/
RAR RUS 13909-13909 57196438866 0000-0002-1035-887X Tambov State Technical University Erofeev Alexander AV.Erofeev@yandex.ru
Tambov, Russia
 Durability prediction method for building materials The prediction of durability can be approached from the perspective of the thermal fluctuation concept of fracture and deformation of solids. One of the drawbacks of this concept is the high labor intensity involved in determining the thermal fluctuation constants of the generalized Zhurkov equation, as well as the significant errors that may occur in their determination. The aim of this study is to develop methodologies that address and mitigate these shortcomings. The main scientific approaches employed are the hypothetical method and experimental studies (determining the durability of solids under non-destructive stress conditions). A description is provided of a developed methodology for determining thermal fluctuation constants based on a single straight line and one control point. The advantage of this approach is that it reduces the number of required experimental investigations by almost a factor of three. In the classical case, 15 points must be determined, whereas the proposed method requires only six. The main disadvantage of the method is the reduction in the accuracy of determining thermal fluctuation constants. Therefore, it is recommended for cases where approximate values are sufficient and minimal labor costs are desired. A description is also provided of the so-called “reference beam” method. This methodology is based on bringing the obtained fan-shaped family of straight lines converging at a single point (pole) to a selected reference family and determining thermal fluctuation constants using a system of conversion coefficients. Another proposed methodology makes it possible to determine the durability of solids without explicitly determining the thermal fluctuation constants. This method is based on a theoretically derived formula from the generalized Zhurkov equation for direct durability evaluation. The latter two methodologies increase the reliability of durability prediction for solids from the standpoint of the thermal fluctuation concept of fracture and deformation. The first of these methodologies significantly reduces the labor intensity of determining the thermal fluctuation constants of the generalized Zhurkov equation. 10.34910/MCE.139.9 691 building materials durability efficiency forecasting generalized Zhurkov equation thermal fluctuation constants thermal fluctuation https://engstroy.spbstu.ru/article/2025.139.9/
RAR RUS 13910-13910 University of Anbar Raoof Ban Z ban22e1008@uoanbar.edu.iq
Ramadi, Iraq
 University of Anbar Abdulkareem Ahmed ahm1973ed@uoanbar.edu.iq
Ramadi, Iraq
 0000-0003-4420-0576 University of Anbar Rajab Ahmed Rahomi ahmed.rahomi2@uoanbar.edu.iq
Ramadi, Iraq
 Implementation of geopolymer for stabilizing granular soil River sand, despite being an available material, a low-cost, but loose sandy soil, cannot be used as a construction material in civil engineering works due to its poor grain size distribution and low bearing capacity. Geopolymer is recently considered a novel eco-friendly alternative to conventional soil enhancement and stabilization materials, such as ordinary Portland cement (OPC) and lime, which harm the environment in terms of high CO2 emissions and energy consumption. Hence, this study investigated the potential strengthening of loose sandy soil using geopolymer. Different alkaline activator (AA) solution ratios were used with varying curing temperatures for producing the river-sand geopolymer. The river sand-geopolymer specimens were matured in the oven at different temperatures for 48 hours. A series of unconfined compressive strength (UCS) tests were carried out on the 3, 7, 14, and 28 days of curing. The results show that the UCS of the river-sand geopolymer matrix significantly increased with increasing the main ingredient of its activator solution (sodium silicate) as well as the temperature. The UCS reached 13.42 MPa when the AA solution ratio was 0, whereas it decreased up to 1.15 MPa when the AA solution ratio became 1.5 at a temperature of 60 °C and 28 days of curing. Therefore, geopolymer is feasible and sustainable material to improve problematic soil for different applications. 10.34910/MCE.139.10 624 Granular soil geopolymer soil stabilization sustainable material https://engstroy.spbstu.ru/article/2025.139.10/