jcer_1786735479 20260814192439000 CMV Verlag khoffman@cmv-verlag.com In collaboration with Golestan University and Assoc. Prof. Dr. Morteza Jamshidi Journal of Civil Engineering Researchers jcer 2538-516X 2538-516X 12 01 2025 7 4 Shadzi Rezaei Hakim Sabzevari University https://ror.org/00zyh6d22 Rasoul Shadnia Hakim Sabzevari University https://ror.org/00zyh6d22 Mojtaba Lezgi Nazarghah Hakim Sabzevari University https://ror.org/00zyh6d22 Concrete is one of the most widely used construction materials globally; however, its production contributes significantly to carbon dioxide emissions. In the Middle East, annual date production is substantial, and date seeds, as a byproduct, are typically discarded. This study investigates three methods for incorporating date seeds into concrete: (1) Cement replacement: Using powdered date seeds (PDS) as a partial substitute for cement at 5%, 10%, 15%, and 20% levels; (2) Aggregate replacement: Replacing coarse aggregates with crushed date seeds (CDS) at 10%, 20%, and 30% ratios and (3) Hybrid approach: Combining PDS (0%, 5%, 10%, and 20%) with fly ash (fixed at 20%). Mechanical tests revealed that replacing cement with up to 10% PDS had no significant impact on compressive strength, whereas higher replacement levels reduced strength. Similarly, increasing the aggregate replacement percentage led to a decline in concrete strength. In contrast, the hybrid approach—combining PDS with 20% fly ash—enhanced compressive strength. Based on these findings, the third method emerged as the most effective for improving both the strength and sustainability of concrete. The optimized hybrid mixture was selected for further comprehensive evaluation, including tests for tensile strength, flexural strength, water absorption (porosity), sulfate resistance, and freeze-thaw durability. These assessments aimed to verify not only the mechanical properties but also the long-term durability of the modified concrete under diverse environmental conditions. 12 01 2025 1 11 https://creativecommons.org/licenses/by/4.0 10.61186/JCER.7.4.1 https://www.journals-researchers.com/ojs/index.php/jcer/article/view/180 https://www.journals-researchers.com/ojs/index.php/jcer/article/download/180/222 https://www.journals-researchers.com/ojs/index.php/jcer/article/download/180/222 Journal of Civil Engineering Researchers jcer 2538-516X 2538-516X 12 01 2025 7 4 Mohammadreza Oliaei Department of Civil Engineering, Ramsar Branch, Islamic Azad University, Ramsar, Iran MohammadHadi Moallemi Department of Civil Engineering, Ramsar Branch, Islamic Azad University, Ramsar, Iran Conventional steel braces increase the risk of structural damage during earthquakes due to compressive buckling. In this study, the performance of a steel frame equipped with a memory alloy cable brace with a central cylinder is investigated through numerical modeling in ABAQUS. This system is expected to exhibit superior seismic performance compared to traditional braces due to characteristics such as superelasticity, self-centering, and energy dissipation, and to return to its initial state after an earthquake. It can significantly enhance the seismic performance of steel frames with minimal construction interference and reduced construction time. After model validation, this study evaluates the effects of cable type, memory alloy properties, and cable diameter on the lateral performance of the steel frame with central cylinder cable braces. The results indicate that even using steel cables in this system significantly increases strength, stiffness, and energy absorption compared to a frame without braces, although ductility decreases by 25%. Replacing the steel cable with a memory alloy cable simultaneously improves strength, stiffness, energy absorption, and ductility (by 10%) compared to the steel-cable specimen, compensating for the ductility reduction. Furthermore, enhancing the superelastic properties of the memory alloy increases the load-bearing capacity and absorbed energy, while increasing the memory alloy cable diameter (from 6 to 16 mm) improves all performance indicators, especially stiffness and strength, without significant loss of ductility. Overall, the results demonstrate that using memory alloy cables, along with optimizing their properties and diameter, is an effective approach for simultaneously improving strength, stiffness, ductility, energy dissipation, and seismic behavior of structures. 12 01 2025 12 22 https://creativecommons.org/licenses/by/4.0 10.61186/JCER.7.4.12 https://www.journals-researchers.com/ojs/index.php/jcer/article/view/212 https://www.journals-researchers.com/ojs/index.php/jcer/article/download/212/217 https://www.journals-researchers.com/ojs/index.php/jcer/article/download/212/217 Journal of Civil Engineering Researchers jcer 2538-516X 2538-516X 12 01 2025 7 4 Saleh Aminyavari Department of Civil Engineering, Chalous Branch, Islamic Azad University, Chalous, Iran This study presents the first application of gamma quantile mapping to bias-correct ensemble precipitation forecasts from seven global NWP models (ECMWF, NCEP, UKMO, CMA, JMA, ECCC, NCMRWF) in the data-scarce Saliyan Basin, Iran. The integration of these models with advanced bias correction techniques significantly improves flood forecasting accuracy. To address systematic biases in the raw forecasts, gamma quantile mapping was applied, significantly enhancing the reliability of the precipitation inputs. These bias-corrected forecasts were then used as inputs for the GR4J hydrological model to simulate river flow and predict flood events. The study period included a major flood event in March 2019, which was used to evaluate the performance of the ensemble forecasting system. Results demonstrated that bias correction using gamma quantile mapping substantially improved the accuracy of flood forecasts, with the ECMWF and UKMO models showing the highest skill scores. The ensemble approach effectively captured the uncertainty in flood predictions, providing valuable insights for risk assessment and decision-making. This research highlights the importance of bias correction in ensemble forecasting and offers a robust framework for flood prediction in data-scarce regions. The findings have significant implications for improving flood early warning systems and mitigating flood-related damages in similar basins worldwide. 12 01 2025 23 33 https://creativecommons.org/licenses/by/4.0 10.61186/JCER.7.4.23 https://www.journals-researchers.com/ojs/index.php/jcer/article/view/208 https://www.journals-researchers.com/ojs/index.php/jcer/article/download/208/218 https://www.journals-researchers.com/ojs/index.php/jcer/article/download/208/218 Journal of Civil Engineering Researchers jcer 2538-516X 2538-516X 12 01 2025 7 4 Saeed Fallahian Department of Civil Engineering, Shomal University, Amol, Iran Seyed Mohammad Seyedpoor Department of Civil Engineering, Shomal University, Amol, Iran Himan Khodaei Department of Civil Engineering, Shomal University, Amol, Iran Identifying the location and severity of structural damage represents one of the most critical challenges in civil engineering. The ability to identify damage in its earliest stages cannot be overstated in terms of importance. Among the most powerful tools available for damage detection and generally structural health monitoring can name signal data processing. This study uses a two-step procedure based on wavelet theory and an optimization method to identify the location and severety of damage in beams and plates. The damage simulates through the introduction of cracks at targeted locations. Acceleration responses obtained from a dynamic analysis using finite element method undergo wavelet transformation, enabling detailed analysis of the dynamic response signals. Through filtering processes, the structural response signal details are extracted. Disturbances appearing in the signal detail plots indicate the presence of damage, leading to the development of a quantitative index for determining probable damage locations. The second phase is used to properly determine the location and  magnitude of the damage using firefly optimization algorithm. To assess the effectiveness of the proposed method, five numerical examples including three beams with varying characteristics and 16, 27, and 20 elements, respectively, and two plates with different support conditions—one with two-edge fixed supports and another with four-edge fixed supports are considered. Different damage scenarios are considered for structures. The findings indicate that the proposed method shows outstanding results in terms of identifying the location and severity of damage using acceleration responses with considering noise interferences. 12 01 2025 34 67 https://creativecommons.org/licenses/by/4.0 10.61186/JCER.7.4.34 https://www.journals-researchers.com/ojs/index.php/jcer/article/view/190 https://www.journals-researchers.com/ojs/index.php/jcer/article/download/190/219 https://www.journals-researchers.com/ojs/index.php/jcer/article/download/190/219 Journal of Civil Engineering Researchers jcer 2538-516X 2538-516X 12 01 2025 7 4 Mahdi Mashhadiyan Department of Civil Engineering, Ramsar Branch, Islamic Azad University, Ramsar, Iran Jalal AkbarKamali Department of Civil Engineering, Ramsar Branch, Islamic Azad University, Ramsar, Iran Esmaeil Mousapoor Department of Civil Engineering, Ramsar Branch, Islamic Azad University, Ramsar, Iran Re-centering dampers, developed using shape memory alloy (SMA)-based dampers and their superelasticity capability, absorb earthquake energy and provide a re-centering capability for the structure. In this study, the laboratory sample of Zhang's re-centering damper was first validated using ABAQUS software, followed by parametric analysis involving changes in the number and diameter of SMA rods, the friction coefficient of the wedges, and the placement configuration of two dampers, which were numerically investigated. The results indicated that increasing the diameter and number of rods, as well as the friction coefficient, enhances seismic resistance and stiffness but reduces ductility; excessive increase in friction only boosts the stiffness and ductility of the damper's compressive section while reducing seismic resistance. A friction coefficient of approximately 0.12 is recommended, whereas Zhang assumed 0.09. Additionally, the results showed: in parallel configuration, resistance and stiffness are higher but ductility is lower, whereas in series configuration, all three parameters decrease. 12 01 2025 68 77 https://creativecommons.org/licenses/by/4.0 10.61186/JCER.7.4.68 https://www.journals-researchers.com/ojs/index.php/jcer/article/view/213 https://www.journals-researchers.com/ojs/index.php/jcer/article/download/213/214 https://www.journals-researchers.com/ojs/index.php/jcer/article/download/213/214 Journal of Civil Engineering Researchers jcer 2538-516X 2538-516X 12 01 2025 7 4 A.R. Gorji Department of Civil Engineering, Faculty of Engineering, Hakim Sabzevari University, Sabzevar 9617976487-397, Iran M. Lezgy-Nazargah Hakim Sabzevari University https://ror.org/00zyh6d22 Department of Civil Engineering, Faculty of Engineering, Hakim Sabzevari University, Sabzevar 9617976487-397, Iran A. Ghafourian-Mojaver Department of Civil Engineering, Faculty of Engineering, Hakim Sabzevari University, Sabzevar 9617976487-397, Iran M. Tayebinia Department of Civil Engineering, Faculty of Engineering, Hakim Sabzevari University, Sabzevar 9617976487-397, Iran Until now, various mathematical models have been proposed to characterize the behavior of viscoelastic materials and facilitate their implementation in finite element software. However, it remains unclear which configuration of the viscoelastic layer along the thickness and length of the beam yields the lowest creep deflection and highest damping effect under applied forces. To fill this literature gap, efforts are undertaken in this study to identify the optimal placement of the viscoelastic layers in the sandwich beam. To reach this aim, the creep and dynamic behaviors of sandwich beams with different boundary conditions and various configurations of the viscoelastic layer along the thickness and length were investigated using a finite element model. The obtained results indicate that the damping capability and creep deformations of the sandwich beam are strongly affected by the position of the viscoelastic layers. 12 01 2025 78 87 https://creativecommons.org/licenses/by/4.0 10.61186/JCER.7.4.78 https://www.journals-researchers.com/ojs/index.php/jcer/article/view/184 https://www.journals-researchers.com/ojs/index.php/jcer/article/download/184/220 https://www.journals-researchers.com/ojs/index.php/jcer/article/download/184/220 Journal of Civil Engineering Researchers jcer 2538-516X 2538-516X 12 01 2025 7 4 Abdolah Ataeifar Department of Civil Engineering, BaA.C., Islamic Azad University, Bandar Anzali, Iran Ata Jafary Shalkoohy Department of Civil Engineering, BaA.C., Islamic Azad University, Bandar Anzali, Iran Payam Eshghi Department of Civil Engineering, BaA.C., Islamic Azad University, Bandar Anzali, Iran Hamidreza Ghaderi Niri Department of Civil Engineering, Qa.C., Islamic Azad University, Qazvin, Iran Expansive clay soils are characterized by their high water affinity and significant volume changes, which frequently result in structural issues such as swelling, settlement, and cracking, particularly under freeze–thaw (F–T) conditions. This study investigates a dual-stabilization method using fly ash (FA: 5–15%) and graphene oxide (GO: 0.05–0.15%) to enhance the mechanical strength and durability of such soils. After 28 days of curing, samples underwent 3, 6, and 9 F–T cycles, followed by unconfined compressive strength (UCS) testing. Results show that the GO–FA combination significantly improved soil performance, with the optimal mix (10% FA + 0.1% GO) achieving a 76% increase in UCS at zero cycles and reducing strength loss after nine cycles by over 45% compared to untreated soil. These outcomes demonstrate the promise of GO–FA stabilization as a sustainable and effective solution for expansive soils in cold-region geotechnical engineering. 12 01 2025 88 99 https://creativecommons.org/licenses/by/4.0 10.61186/JCER.7.4.88 https://www.journals-researchers.com/ojs/index.php/jcer/article/view/189 https://www.journals-researchers.com/ojs/index.php/jcer/article/download/189/221 https://www.journals-researchers.com/ojs/index.php/jcer/article/download/189/221