Amirkabir University of TechnologyAUT Journal of Civil Engineering2588-289910320260701A Goal Programming-Based Framework for Multi-Objective Optimization of Sustainable Concrete Pavements Mix Design193210605810.22060/ajce.2026.25066.5962ENAli AkbarShirzadi JavidAssociate Professor, School of Civil Engineering, Iran University of Science and Technology, P.O. Box 16765-163, Narmak, Tehran, Iran.0000-0002-6105-5991Mohammad AliEtebari GhasbehM.Sc. graduate, School of Civil Engineering, Iran University of Science and TechnologyJournal Article20251108The use of concrete pavement has significantly increased due to its advantages over asphalt pavement. Determining the concrete mix ratio for asphalt is a vital and crucial step in the construction process. Concrete should be strong, durable, and resistant to environmental degrading factors. This means it needs to withstand freezing, thawing, shrinkage, and harsh environmental conditions (such as heat and cold. These characteristics result in concrete having a longer lifespan and creating robust structures). One of the challenges in design is balancing quality and cost, which comes with its own complexities.. Over the past few years, the application of models and algorithms for multi-objective problems has been a focus of research. This study introduces adaptive neuro-fuzzy inference system goal programming (NFGPM) and fuzzy-goal programming model (FGPM) as expanded variants of basic goal programming models, as alternative tools for allocating asphalt concrete pavement mixtures proportions with multiple, varied objectives. The actual data laboratory experiment datasets were generated and used to develop proposed models. The outcomes of the proposed NFGPM’s mixture proportions and its prediction of concrete properties —such as slump, flexural strength, abrasion resistance, shrinkage and freeze–thaw behavior— are compared with experimental data. The study confirms that the adaptive neuro-fuzzy inference system goal programming model proposed herein can deliver the most cost-effective and optimally performing concrete pavement mixture proportions.https://ajce.aut.ac.ir/article_6058_5b8e9841e87fb8fc590434f5d933c92c.pdfAmirkabir University of TechnologyAUT Journal of Civil Engineering2588-289910320260701Effect of nano magnesium oxide and microsilica on the mechanical behavior of fiber reinforced concrete211226607610.22060/ajce.2026.24740.5946ENMojtabaEtemadiDepartment of Civil Engineering, Mahdishahr Branch, Islamic Azad University, Mahdishahr, IranHamidBeiraghiDepartment of Civil Engineering, Mahdishahr Branch, Islamic Azad University, Mahdishahr, IranJournal Article20250914This study investigates the synergistic influence of nano magnesium oxide (nMgO), microsilica (silica fume), and polypropylene (PP) fibers on both fresh and hardened properties of concrete, aiming to propose an optimized hybrid mixture for structural applications. The novelty lies in the integrated, multi-scale approach—combining nano (nMgO), micro (microsilica) and macro (PP fibers) constituents—and a systematic experimental program covering 16 mix variants. Specimens were prepared with nMgO dosages of 0–2% and PP fibers of 0–1.4% by cement weight, while microsilica was kept at 4% replacement of cement. Mechanical tests (compressive, splitting tensile, flexural) were performed at 7, 28 and 90 days; water absorption was measured at 28 days. All reported values are the mean of replicates (n=3) and statistical dispersion is reported alongside mean values (raw data available upon request). The optimum performance was observed for the mix containing 0.5% nMgO and 0.8% PP fibers, which produced improvements up to 18% in compressive strength, 22% in splitting tensile strength and 20% in flexural strength relative to the control mix, while reducing water absorption from 4.3% to 3.1%. Mechanistic interpretation attributes these gains to combined pore-filling and nucleation effects of nMgO, pozzolanic reaction of microsilica improving C–S–H content, and fiber-bridging improving post-crack behavior. Limitations and reproducibility (replicates, statistical reporting) are discussed.https://ajce.aut.ac.ir/article_6076_beb22abb9ec56c0cf7ec7d811dd91a56.pdfAmirkabir University of TechnologyAUT Journal of Civil Engineering2588-289910320260701Progressive Collapse Assessment of Steel Moment Frames with the RBS Connections by Considering Different Seismicity and Ductility Levels227242607710.22060/ajce.2026.24128.5919ENBehzadRezaieDepartment of Civil Engineering, Amirkabir university of technology, Tehran, IranPayamTehraniDepartment of Civil Engineering, Amirkabir university of technology, Tehran, Iran0000-0001-5171-4239BehrouzBehnamDepartment of Civil Engineering, Amirkabir university of technology, Tehran, Iran0000-0002-8348-4711Journal Article20250505Extreme events such as earthquakes can damage vertical load-bearing elements, particularly columns, potentially triggering progressive collapse in building systems. This vulnerability is more pronounced in steel moment-resisting frames due to their relatively limited redundancy. Although previous studies have investigated the progressive collapse behavior of moment frames under different seismicity and ductility levels, the influence of key seismic design parameters—such as reduced beam section (RBS) connections, ductility level, and the strong column–weak beam (SC–WB) principle—remains insufficiently understood, with conflicting findings reported in the literature. This study aims to systematically evaluate the role of these seismic design parameters in the progressive collapse response of steel moment frames. To this end, 5-, 10-, and 15-story buildings were designed for low, medium, and high seismicity levels, considering both intermediate and special moment frames with RBS connections. A total of 340 column removal scenarios were analyzed using nonlinear dynamic analysis in OpenSees, employing a lumped plasticity modeling approach. Structural performance was assessed in terms of damage percentage index (DPI), ductility demand, and vertical nodal displacement. The results indicate that ductility demands in all cases remained within code-prescribed performance limits, suggesting that RBS connections provide adequate robustness against progressive collapse under column removal scenarios. However, neglecting the SC–WB principle significantly increases ductility demand and vertical displacement, by up to 1.83 and 1.56 times, respectively, in critical cases. Furthermore, the ductility level of the lateral-resisting system strongly influences structural response, particularly in medium seismicity conditions, where weaker member sizes lead to reduced robustness and amplified deformation demands.https://ajce.aut.ac.ir/article_6077_58182b82110146887c02dbd78719e3d5.pdfAmirkabir University of TechnologyAUT Journal of Civil Engineering2588-289910320260701Evaluation of In-situ Concrete Strength using Maturity-Based Strength Modification Factor (SMF): A Field Study in Various Climatic Conditions243254607810.22060/ajce.2026.24163.5924ENSasanMotaghedDepartment of Civil Engineering, Faculty of Civil engineering and architecture, Shahid Chamran University of Ahvaz, Ahvaz, Iran0000-0001-7062-0457AminMashhadiBehbahan Khatam Alanbia University of TechnologyAbbasHosseiniYasouj UniversityMohammad SadeghShahidzadehBehbahan Khatam Alanbia University of TechnologyHadiSayadpourYasouj UniversityJournal Article20250515Accurate estimation of in-situ concrete compressive strength is vital for structural safety and optimizing construction schedules. However, significant discrepancies often exist between standard laboratory-cured specimens and actual field performance due to varying on-site temperature and curing conditions. This study proposes a practical approach to bridge this gap by employing the maturity method to derive a site-specific strength modification factor (SMF). The proposed method was rigorously validated using extensive data collected from five active construction sites in southern Iran, which encompassed a wide range of concrete mix designs and local climatic conditions. A total of twelve experimental series were conducted, directly comparing the compressive strength development of standard laboratory-cured specimens with companion field-cured samples at 7 and 28 days of age.The results establish a significant and quantifiable correlation between the calculated SMF and the ambient curing temperature. Specifically, the SMF at 7 days averaged 1.30 during colder seasons, indicating lower early strength in the field, and 0.86 during warmer seasons. By applying this temperature-dependent SMF to standard laboratory results, the mean prediction error for in-situ strength was substantially reduced from approximately 14% to less than 4%. These findings demonstrate that the SMF approach provides a reliable, quantitatively robust framework for adjusting controlled laboratory data to accurately reflect real-world curing environments. Consequently, this method offers a powerful tool for enhancing on-site quality control protocols and enabling safer, more efficient, and data-driven decisions regarding formwork removal and subsequent construction activities.https://ajce.aut.ac.ir/article_6078_5f8a7deb15235a128fcd99ad6bfde11e.pdfAmirkabir University of TechnologyAUT Journal of Civil Engineering2588-289910320260701Experimental Evaluation of Asphalt Concrete Interlayer Shear Strength: Role of Thermal, Bonding, and Structural Factors255268607910.22060/ajce.2026.24563.5938ENAliDehqaniDepartment of Civil and Environmental Engineering, Amirkabir University of Technology, Tehran, IranMahdiShojaeiDepartment of Civil and Environmental Engineering, Amirkabir University of Technology, Tehran, Iran0000-0002-2897-3395FereidoonMoghadas NejadDepartment of Civil and Environmental Engineering, Amirkabir University of Technology, Tehran, IranJournal Article20250814Bonding characteristics between asphalt concrete layers have been a major concern for decades, as poor adhesion can lead to premature pavement distress, including cracking and fatigue. Hence, this study investigates the individual and interactive effects of temperature, tack coat application rate, confinement load, aggregate interlock, surface preheating, and geocomposite reinforcement on interlayer shear strength. The results showed that temperature is the most detrimental factor, reducing the strength overall by more than 2.5 times as it increased from 10°C to 40°C. Meanwhile, confinement load and aggregate interlock are the most important contributors to strength. Applying a 100 kPa confinement pressure boosted average strength by 60%, and aggregate interlock increased strength by 28% at high temperatures. Furthermore, statistical analysis revealed that surface preheating has no significant impact on the final strength. Importantly, critical interactions between confinement load and tack coat rate, as well as a negative interaction between aggregate interlock and the geocomposite, were recognised. Specifically, while aggregate interlock significantly increased strength by 28% at 40°C, the addition of geocomposites introduced a negative interaction, reducing the shear strength by approximately 17%. This finding quantifies the trade-off, demonstrating that geocomposites can partially negate the mechanical benefits of interlock. These results provide a robust framework for optimising pavement design by prioritising synergistic factor combinations.https://ajce.aut.ac.ir/article_6079_b1b20d09041289e6c3fbb81850c5da54.pdfAmirkabir University of TechnologyAUT Journal of Civil Engineering2588-289910320260701Post-Cyclic Fire Response of Buckling-Restrained Braced Frames269288608010.22060/ajce.2026.24779.5948ENHosseinParasteshDepartment of Civil Engineering, University of Science and Culture, Tehran, Iran0000-0002-5828-2552RaminMohammadzadeh SargheinAshrafi E esfahani Blv., Sadeghiyeh Sq.Journal Article20250920In this study, after validating the numerical simulation procedures, a three-dimensional model of a regular steel moment-resisting frame equipped with buckling-restrained braces (BRBs) was developed using Abaqus. A coupled displacement-thermal analysis was conducted on the frame under fire exposure following cyclic lateral loading. The effects of fire temperature, loading amplitude, and BRB geometric parameters on the frame's behavior were investigated. Results showed that increasing the fire temperature applied to the bottom-story columns and braces (from 777°C to 1067°C) raised the lateral force, bending moment, and rotation of the frame during fire exposure after cyclic loading. This increase highlights the sensitivity of steel moment frames (including those with BRBs) to fire temperature, especially at higher temperatures. Furthermore, under various fire temperatures, raising the cyclic lateral loading amplitude from 30 mm to 60 mm led to significant increases in lateral force (60%), bending moment (60%), and rotation (116%) during fire exposure. This demonstrates the high sensitivity of frame behavior to fire temperature at large loading amplitudes. Finally, reducing the BRB core thickness from 6 mm to 2 mm (particularly from 6 mm to 4 mm) under different fire temperatures decreased lateral force (67%), bending moment (67%), and rotation (56%) during fire exposure. This reduction indicates the strong sensitivity of BRB behavior, and consequently of the braced steel moment frame, to fire temperature and BRB geometric parameters, especially core thickness.https://ajce.aut.ac.ir/article_6080_940392f5f32a7ade1cc201767cf83e31.pdf