University of QomCivil Infrastructure Researches2783-140X11120250522Investigating Uncertainty in Seismic Design Maps Based on Hazard and Fragility CurvesInvestigating Uncertainty in Seismic Design Maps Based on Hazard and Fragility Curves114321410.22091/cer.2024.11285.1572FAAlirezaZarrineghbalAssistant Professor, Department of Civil Engineering, Faculty of Technology and Engineering, Qom University of Technology, Qom, Iran.0009-0007-2572-5218HamidZafaraniProfessor of Earthquake Engineering & Engineering Seismology, IIEES, Tehran, IR IRAN.0000-0002-4431-9692Journal Article20240901All engineering measurements carry inherent uncertainty, whether acknowledged or not. If we add a type of risk metric as well as uncertainty quantification in the procedure of establishing the seismic design load applied to the structures, we will have a risk-informed approach for the resulting design load referred to as the risk-based seismic design hazard. For example, ASCE/SEI 43-05 standard uses a risk-based approach to prepare the seismic design spectra to be applied to the nuclear power plants (NPPs). This approach necessitates the propagation of uncertainty in ground motion model (i.e., the hazard curve), as well as probabilistic distribution of structural capacity levels (i.e., the fragility curve). The present research begins with the specifics of this approach, in particular the whole shape of the earthquake hazard curve and its integration with the structural fragility curve for estimating the seismic design load. The aim is to identify for a probabilistic model that can estimate the uncertainty of seismic design loads for a variety of engineering structures. This paper presents the estimated uncertainties of seismic design loads across the Iran map using the developed probabilistic model. The uncertainty, according to the study's assumptions, is at least 45% in terms of the coefficient of variation, indicating a significant value. The estimated variability in seismic design loads in the Iran region ranges from 45% to 90%.All engineering measurements carry inherent uncertainty, whether acknowledged or not. If we add a type of risk metric as well as uncertainty quantification in the procedure of establishing the seismic design load applied to the structures, we will have a risk-informed approach for the resulting design load referred to as the risk-based seismic design hazard. For example, ASCE/SEI 43-05 standard uses a risk-based approach to prepare the seismic design spectra to be applied to the nuclear power plants (NPPs). This approach necessitates the propagation of uncertainty in ground motion model (i.e., the hazard curve), as well as probabilistic distribution of structural capacity levels (i.e., the fragility curve). The present research begins with the specifics of this approach, in particular the whole shape of the earthquake hazard curve and its integration with the structural fragility curve for estimating the seismic design load. The aim is to identify for a probabilistic model that can estimate the uncertainty of seismic design loads for a variety of engineering structures. This paper presents the estimated uncertainties of seismic design loads across the Iran map using the developed probabilistic model. The uncertainty, according to the study's assumptions, is at least 45% in terms of the coefficient of variation, indicating a significant value. The estimated variability in seismic design loads in the Iran region ranges from 45% to 90%.https://cer.qom.ac.ir/article_3214_20694516fe26a2ae9c485d1878c5e240.pdfUniversity of QomCivil Infrastructure Researches2783-140X11120250522Evaluation of Location and Development Plan Management in New Settlements in Areas with Potential Flood Risk: A Case Study of the 560-Hectare Pardisan Site in QomEvaluation of Location and Development Plan Management in New Settlements in Areas with Potential Flood Risk: A Case Study of the 560-Hectare Pardisan Site in Qom1534332910.22091/cer.2025.11685.1586FASeyed Mohammad HosseinDehnadDepartment of Civil Engineering, Faculty of Engineering, University of Qom, Qom, Iran.0000-0001-5045-8499AbolfazlFaraji MondaredFaculty of Planning and Environmental Sciences, University of Tabriz, Tabriz, Iran.0009-0005-6122-2082MohammadAghazadehDoctor of Geography and Urban Planning, Tehran University of Science and Research,Municipal Research Department, Qom, Iran0009-0001-6224-5201Journal Article20241122Due to their susceptibility to flooding, alluvial fan surfaces present unique challenges for development. The scope of Pardisan is also expanded in these areas, necessitating a comprehensive location and development plan. To address this, a robust methodology was employed, incorporating flood risk modeling using HEC-RAS and the Soil Conservation Service (SCS) method to calculate the flow rate of a 100-year flood event. In addition to the flood factor, 13 other criteria were included based on expert opinions to assess the suitability of the land for development. These criteria were analyzed using the Analytical Hierarchy Process (AHP) in conjunction with fuzzy logic, facilitating an accurate comparison of potential sites for expansion. The findings reveal that, despite existing watershed management efforts, the current residential areas in Pardisan remain vulnerable to flooding and inadequately address the volume and sediment challenges posed by potential flood events. This research underscores the deficiencies in current flood prevention measures and highlights the necessity for enhanced strategies and further studies. The results of the Fuzzy Analytical Hierarchy Process (FAHP) model identified the southeastern part of Pardisan as the most suitable area for development, which contradicts the current development plan. This recommendation is based on a thorough evaluation of the specified criteria and indicates significant potential for targeted and optimal urban development. Finally, it is important to note that the integrated HEC-RAS-SCS-FAHP model can serve as a valuable roadmap for urban area development.Due to their susceptibility to flooding, alluvial fan surfaces present unique challenges for development. The scope of Pardisan is also expanded in these areas, necessitating a comprehensive location and development plan. To address this, a robust methodology was employed, incorporating flood risk modeling using HEC-RAS and the Soil Conservation Service (SCS) method to calculate the flow rate of a 100-year flood event. In addition to the flood factor, 13 other criteria were included based on expert opinions to assess the suitability of the land for development. These criteria were analyzed using the Analytical Hierarchy Process (AHP) in conjunction with fuzzy logic, facilitating an accurate comparison of potential sites for expansion. The findings reveal that, despite existing watershed management efforts, the current residential areas in Pardisan remain vulnerable to flooding and inadequately address the volume and sediment challenges posed by potential flood events. This research underscores the deficiencies in current flood prevention measures and highlights the necessity for enhanced strategies and further studies. The results of the Fuzzy Analytical Hierarchy Process (FAHP) model identified the southeastern part of Pardisan as the most suitable area for development, which contradicts the current development plan. This recommendation is based on a thorough evaluation of the specified criteria and indicates significant potential for targeted and optimal urban development. Finally, it is important to note that the integrated HEC-RAS-SCS-FAHP model can serve as a valuable roadmap for urban area development.https://cer.qom.ac.ir/article_3329_0374973a939b023afba96866b2eb4144.pdfUniversity of QomCivil Infrastructure Researches2783-140X11120250522Effects of NaOH Concentration and Na2SiO3/NaOH Ratio on the Performance of Self-Compacted Geopolymer Concrete Containing ScoriaEffects of NaOH Concentration and Na2SiO3/NaOH Ratio on the Performance of Self-Compacted Geopolymer Concrete Containing Scoria3550332710.22091/cer.2025.11254.1570FAAmir RezaShamsiFaculty of Engineering, Department of Civil Engineering, Golestan University, Gorgan, Iran.0009-0004-8586-4613S. YasinMousaviFaculty of Engineering, Department of Civil Engineering, Golestan University, Gorgan, Iran.0000-0001-6966-0443Ali RezaTabarsaFaculty of Engineering, Department of Civil Engineering, Golestan University, Gorgan, Iran.0000-0001-5475-122XJournal Article20240924Understanding the key variables that affect the performance of lightweight self-compacting geopolymer concrete (LSGPC) is essential for harnessing its technical and environmental benefits in real-world applications. This study aims to investigate the effect of NaOH concentration (6, 8 and 10M) and Na2SiO3/NaOH ratio (0.5, 1.5 and 2.5) on the performance of LSGPC containing scoria. For this purpose, 10 LSGPCs were produced and tested for slump flow, T50, visual stability index, V- funnel and J-ring in the fresh state and compressive strength, splitting tensile strength and water absorption in the hardened state. Results showed that using 100% scoria as a substitution of coarse aggregate reduces slump flow and increases T50 and V- funnel times due to the reduction in the weight of the mixture. Moreover, NaOH concentration and Na2SiO3/NaOH ratio with a change in the viscosity of the mixture are the factors influencing the fresh state performance of LSGPC. Microstructure observation of LSGPC samples by using SEM images revealed a stronger interfacial transition zone between the geopolymer paste and aggregate which improves the mechanical properties as the NaOH concentration increases from 6M to 10M. Furthermore, Na2SiO3/NaOH ratio of 1.5 in LSGPC mixture had the best performance in terms of increasing mechanical properties and reducing water absorption. In general, considering optimum concentration of NaOH and Na2SiO3/NaOH ratio, it is possible to produce LSGPC containing 100% scoria with acceptable fresh state properties as well as compressive strength categorized as lightweight structural concrete.Understanding the key variables that affect the performance of lightweight self-compacting geopolymer concrete (LSGPC) is essential for harnessing its technical and environmental benefits in real-world applications. This study aims to investigate the effect of NaOH concentration (6, 8 and 10M) and Na2SiO3/NaOH ratio (0.5, 1.5 and 2.5) on the performance of LSGPC containing scoria. For this purpose, 10 LSGPCs were produced and tested for slump flow, T50, visual stability index, V- funnel and J-ring in the fresh state and compressive strength, splitting tensile strength and water absorption in the hardened state. Results showed that using 100% scoria as a substitution of coarse aggregate reduces slump flow and increases T50 and V- funnel times due to the reduction in the weight of the mixture. Moreover, NaOH concentration and Na2SiO3/NaOH ratio with a change in the viscosity of the mixture are the factors influencing the fresh state performance of LSGPC. Microstructure observation of LSGPC samples by using SEM images revealed a stronger interfacial transition zone between the geopolymer paste and aggregate which improves the mechanical properties as the NaOH concentration increases from 6M to 10M. Furthermore, Na2SiO3/NaOH ratio of 1.5 in LSGPC mixture had the best performance in terms of increasing mechanical properties and reducing water absorption. In general, considering optimum concentration of NaOH and Na2SiO3/NaOH ratio, it is possible to produce LSGPC containing 100% scoria with acceptable fresh state properties as well as compressive strength categorized as lightweight structural concrete.https://cer.qom.ac.ir/article_3327_55c511368292f4ce742b79acd5ef5112.pdfUniversity of QomCivil Infrastructure Researches2783-140X11120250522Assessing Flexural Behavior of Stabilized and Reinforced ClayAssessing Flexural Behavior of Stabilized and Reinforced Clay5167342110.22091/cer.2025.12150.1596FAMahmood RezaAbdiFaculty of Civil Engineering, K.N. Toosi University of Technology, Tehran, Iran.0000-0002-3473-9677ElhamAbbasiFaculty of Civil Engineering, K. N. Toosi University of Technology, Tehran, Iran.0009-0007-2549-9679MahdiSafdari Seh GonbadFaculty of Civil Engineering, K. N. Toosi University of Technology, Tehran, Iran.0000-0003-0612-535XJournal Article20250118In this study, the flexural behavior of stabilized and reinforced clay was investigated. For this purpose, kaolinite, lime at weight dosages of 1%, 3%, and 5%, as well as polypropylene fibers of 6 mm and 12 mm in length, and weight contents of 0.15%, 0.25%, and 0.35% were utilized. Samples were cured in a laboratory environment at 20-25°C for periods of 7 and 28 days. For quantitative and qualitative evaluations, three-point bending tests and scanning electron microscopy were employed. Results indicated that stabilization increased the flexural strength and brittleness of kaolinite, while simultaneous reinforcement and stabilization improved both strength and ductility. Furthermore, findings demonstrated that flexural strength and strain at maximum stress are directly related to fiber content, fiber length, lime dosage, and curing time. Specifically, increasing fiber content from 0.15% to 0.35%, fiber length from 6 mm to 12 mm, raising lime dosage from 1% to 5%, and extending curing period from 7 days to 28 days improved the flexural strength of the stabilized and reinforced samples by 6%-18%, 20%-43%, 141%-178%, and 5%-17%, respectively. Similarly, strain corresponding to maximum stress was enhanced by 10%-25%, 28%-74%, 88%-161%, and 10%-34%. Qualitative analyses revealed that stabilization improves interactions at soil-fibers interfaces.In this study, the flexural behavior of stabilized and reinforced clay was investigated. For this purpose, kaolinite, lime at weight dosages of 1%, 3%, and 5%, as well as polypropylene fibers of 6 mm and 12 mm in length, and weight contents of 0.15%, 0.25%, and 0.35% were utilized. Samples were cured in a laboratory environment at 20-25°C for periods of 7 and 28 days. For quantitative and qualitative evaluations, three-point bending tests and scanning electron microscopy were employed. Results indicated that stabilization increased the flexural strength and brittleness of kaolinite, while simultaneous reinforcement and stabilization improved both strength and ductility. Furthermore, findings demonstrated that flexural strength and strain at maximum stress are directly related to fiber content, fiber length, lime dosage, and curing time. Specifically, increasing fiber content from 0.15% to 0.35%, fiber length from 6 mm to 12 mm, raising lime dosage from 1% to 5%, and extending curing period from 7 days to 28 days improved the flexural strength of the stabilized and reinforced samples by 6%-18%, 20%-43%, 141%-178%, and 5%-17%, respectively. Similarly, strain corresponding to maximum stress was enhanced by 10%-25%, 28%-74%, 88%-161%, and 10%-34%. Qualitative analyses revealed that stabilization improves interactions at soil-fibers interfaces.https://cer.qom.ac.ir/article_3421_c9f9bbb0d2c2dffcd6f2cdb6bf24d172.pdfUniversity of QomCivil Infrastructure Researches2783-140X11120250522Developing Relationships for Determining the Optimal Shape Parameter in the Multiquadric Meshless MethodDeveloping Relationships for Determining the Optimal Shape Parameter in the Multiquadric Meshless Method6986346010.22091/cer.2025.12181.1598FAHaniehTalebi KalanDepartment of Civil Engineering, Faculty of Engineering, University of Qom, Qom, Iran0009-0006-1178-9045SaraMohsenzadeh GolafzaniDepartment of Civil Engineering, Faculty of Engineering, University of Qom, Qom, Iran0009-0006-6332-6229RezaBabaeeDepartment of Civil Engineering, Faculty of Engineering, University of Qom, Qom, Iran0000-0002-3068-3602EhsanJabbariDepartment of Civil Engineering, Faculty of Engineering, University of Qom, Qom, Iran0000-0002-6345-8567Journal Article20250122The accuracy and efficiency of the Multiquadric Radial Basis Function (MQ-RBF) method are highly sensitive to the choice of the shape parameter. This study aims to identify optimal relationships for determining the shape parameter in solving common partial differential equations (PDEs) encountered in water engineering. To this end, the procedure for reconstructing and solving PDEs using the MQ-RBF method is first outlined. Then, optimal values for the shape parameter are derived based on domain length and the number of computational centers. Based on these findings, empirical formulas for the optimal shape parameter are proposed, which significantly reduce computational cost. The performance of the proposed formulas is compared with exact solutions and existing empirical relations. Results show that, unlike previous approaches, the new formulas offer high accuracy, with negligible errors across different examples-sometimes approaching zero. Moreover, compared to optimization-based techniques, the proposed method dramatically improves computational speed by eliminating the need for iterative algorithms. The study also investigates stability conditions, showing that for diffusion, advection-diffusion, and Burgers’ equations, the maximum allowable time step depends on the diffusion coefficient, flow velocity, and Reynolds number.The accuracy and efficiency of the Multiquadric Radial Basis Function (MQ-RBF) method are highly sensitive to the choice of the shape parameter. This study aims to identify optimal relationships for determining the shape parameter in solving common partial differential equations (PDEs) encountered in water engineering. To this end, the procedure for reconstructing and solving PDEs using the MQ-RBF method is first outlined. Then, optimal values for the shape parameter are derived based on domain length and the number of computational centers. Based on these findings, empirical formulas for the optimal shape parameter are proposed, which significantly reduce computational cost. The performance of the proposed formulas is compared with exact solutions and existing empirical relations. Results show that, unlike previous approaches, the new formulas offer high accuracy, with negligible errors across different examples-sometimes approaching zero. Moreover, compared to optimization-based techniques, the proposed method dramatically improves computational speed by eliminating the need for iterative algorithms. The study also investigates stability conditions, showing that for diffusion, advection-diffusion, and Burgers’ equations, the maximum allowable time step depends on the diffusion coefficient, flow velocity, and Reynolds number.https://cer.qom.ac.ir/article_3460_4babf7576642f832ed4d6272aa165018.pdfUniversity of QomCivil Infrastructure Researches2783-140X11120250522Identification of Damage and Model Updating Using Residual Force Modal Analysis and Optimization AlgorithmsIdentification of Damage and Model Updating Using Residual Force Modal Analysis and Optimization Algorithms87104336110.22091/cer.2025.11502.1584FARezaAghajaniPh.D. Student, Department of Civil Engineering, Urmia Branch, Islamic Azad University, Urmia, Iran.0009-0005-0437-0417OmidAzizpour MiandoabAssistant Professor, Department of Civil Engineering, Urmia Branch, Islamic Azad University, Urmia, Iran.0009-0004-1073-3344Seyed SinaKourehliAssociate Professor, Department of Civil Engineering, Azarbaijan Shahid Madani University, Tabriz, Iran.0000-0001-7599-8053AshkanKhodabandehlouAssociate Professor, Department of Civil Engineering, Urmia Branch, Islamic Azad University, Urmia, Iran.0009-0005-0997-3508Journal Article20241110Currently, detecting structural failures is considered a highly vital and essential method in all branches of engineering. This method assists in improving the quality of life and safety by providing the necessary conditions to increase the useful life of structures and prevent the spread of damage. One of the efficient and widely used methods for detecting failures is to utilize their effects on the dynamic or static responses of structures. This method can serve as a key indicator for detecting and analyzing failures and vulnerable points in structures. In this article, a model updating approach has been employed to detect and determine possible damaged locations in structures. Additionally, a new objective function has been proposed to evaluate the extent of damage based on the combination of residual modal forces and natural frequencies. This objective function, using equilibrium algorithms, differential evolution, cluster analysis, and ant colony optimization, determines the location and severity of existing damages. To assess the accuracy and validity of the presented theory, two numerical examples have been conducted, involving two three-dimensional footings with 25 and 72 elements. These examples cover dual and quadruple damage scenarios in the elements, demonstrating that this theory is capable of accurately detecting the locations and severity of damages in the presence of noisy data and effectively contributing to the correction and improvement of the quality and safety of structures.Currently, detecting structural failures is considered a highly vital and essential method in all branches of engineering. This method assists in improving the quality of life and safety by providing the necessary conditions to increase the useful life of structures and prevent the spread of damage. One of the efficient and widely used methods for detecting failures is to utilize their effects on the dynamic or static responses of structures. This method can serve as a key indicator for detecting and analyzing failures and vulnerable points in structures. In this article, a model updating approach has been employed to detect and determine possible damaged locations in structures. Additionally, a new objective function has been proposed to evaluate the extent of damage based on the combination of residual modal forces and natural frequencies. This objective function, using equilibrium algorithms, differential evolution, cluster analysis, and ant colony optimization, determines the location and severity of existing damages. To assess the accuracy and validity of the presented theory, two numerical examples have been conducted, involving two three-dimensional footings with 25 and 72 elements. These examples cover dual and quadruple damage scenarios in the elements, demonstrating that this theory is capable of accurately detecting the locations and severity of damages in the presence of noisy data and effectively contributing to the correction and improvement of the quality and safety of structures.https://cer.qom.ac.ir/article_3361_a9aef5ee9215dad4d7ee060e7c755d10.pdfUniversity of QomCivil Infrastructure Researches2783-140X11120250522Innovative Approach to Sustainable Construction: Utilization of Refined Travertine Processing By-products as Partial Cement Replacement in
Eco-friendly ConcreteInnovative Approach to Sustainable Construction: Utilization of Refined Travertine Processing By-products as Partial Cement Replacement in
Eco-friendly Concrete105125349610.22091/cer.2025.11940.1588FAPedramHosseiniFaculty of Engineering, Mahallat Institute of Higher Education, Mahallat, Iran.0000-0002-3573-6339AliNaghianFaculty of Engineering, Mahallat Institute of Higher Education, Mahallat, Iran0009-0002-7350-8035AmirAbediFaculty of Engineering, Mahallat Institute of Higher Education, Mahallat, Iran0009-0000-4450-5017Journal Article20241218The construction industry faces significant environmental challenges, with cement production being a major contributor to global CO₂ emissions, while the stone processing industry generates substantial waste material, particularly travertine sludge, creating disposal problems and environmental hazards. This research investigates the potential of Refined Travertine Waste Material (RTWM) as a partial cement replacement in concrete production, with various mixtures prepared using 0% to 50% RTWM replacing cement by mass, and evaluating their mechanical properties and durability characteristics through comprehensive testing at 7, 28, and 90 days. Results demonstrate that RTWM can effectively replace up to 40% of cement without significant strength loss, with optimal performance observed in the 35-40% substitution range, attributed to physical filling effects, improved particle packing, and limited chemical interactions within the cementitious matrix. Water permeability decreased consistently with increasing RTWM content, indicating enhanced durability, and statistical analysis confirmed these findings with regression models providing reliable strength prediction tools. Environmental assessment revealed that optimal RTWM incorporation could reduce CO₂ emissions by up to 32% and energy consumption by approximately 25% in concrete production while maintaining or improving key performance characteristics.The construction industry faces significant environmental challenges, with cement production being a major contributor to global CO₂ emissions, while the stone processing industry generates substantial waste material, particularly travertine sludge, creating disposal problems and environmental hazards. This research investigates the potential of Refined Travertine Waste Material (RTWM) as a partial cement replacement in concrete production, with various mixtures prepared using 0% to 50% RTWM replacing cement by mass, and evaluating their mechanical properties and durability characteristics through comprehensive testing at 7, 28, and 90 days. Results demonstrate that RTWM can effectively replace up to 40% of cement without significant strength loss, with optimal performance observed in the 35-40% substitution range, attributed to physical filling effects, improved particle packing, and limited chemical interactions within the cementitious matrix. Water permeability decreased consistently with increasing RTWM content, indicating enhanced durability, and statistical analysis confirmed these findings with regression models providing reliable strength prediction tools. Environmental assessment revealed that optimal RTWM incorporation could reduce CO₂ emissions by up to 32% and energy consumption by approximately 25% in concrete production while maintaining or improving key performance characteristics.https://cer.qom.ac.ir/article_3496_9cf6f8e9b8c6119b762bd996847ac322.pdfUniversity of QomCivil Infrastructure Researches2783-140X11120250522Effect of Sewage Pollution on Cyclic and Post-Cyclic Behavior of Qom MarlEffect of Sewage Pollution on Cyclic and Post-Cyclic Behavior of Qom Marl127144357210.22091/cer.2025.12093.1594FAMohammad JavadSadeghpourDepartment of Civil Engineering, Faculty of Engineering, University of Qom, Qom, Iran.0009-0006-4051-8092MajidYazdandoustDepartment of Civil Engineering, Faculty of Engineering, University of Qom, Qom, Iran.0000-0003-4355-118XMahdiKhodaparastDepartment of Civil Engineering, Faculty of Engineering, University of Qom, Qom, Iran.0000-0002-4007-4093Journal Article20250118Given the expansion of urban areas, the production of environmental pollutants, such as urban wastewater, has seen significant growth. The complex interaction between environmental pollutants and the geotechnical properties of soil emphasizes the importance of preventive interventions. Therefore, in this study, a series of tests were conducted to investigate the effect of urban wastewater pollution on the monotonic behavior of Qom marl soil, and to explore how the cyclic and post-cyclic behavior of the soil is affected when exposed to a detergent solution as a representative of urban wastewater compounds. Analysis of the results from the simple shear tests showed that the addition of the pollutant led to a reduction in maximum shear strength, cohesion, internal friction angle, and the secant shear modulus, as well as an increase in the soil's damping ratio. On the other hand, cyclic loading resulted in an increase in the maximum shear strength of the soil. Scanning electron microscope (SEM) images revealed that cyclic loading reduced the voids between the soil particles, leading to better particle interlocking. Furthermore, consolidation test results indicated a decrease in the compression index as a result of cyclic loading.Given the expansion of urban areas, the production of environmental pollutants, such as urban wastewater, has seen significant growth. The complex interaction between environmental pollutants and the geotechnical properties of soil emphasizes the importance of preventive interventions. Therefore, in this study, a series of tests were conducted to investigate the effect of urban wastewater pollution on the monotonic behavior of Qom marl soil, and to explore how the cyclic and post-cyclic behavior of the soil is affected when exposed to a detergent solution as a representative of urban wastewater compounds. Analysis of the results from the simple shear tests showed that the addition of the pollutant led to a reduction in maximum shear strength, cohesion, internal friction angle, and the secant shear modulus, as well as an increase in the soil's damping ratio. On the other hand, cyclic loading resulted in an increase in the maximum shear strength of the soil. Scanning electron microscope (SEM) images revealed that cyclic loading reduced the voids between the soil particles, leading to better particle interlocking. Furthermore, consolidation test results indicated a decrease in the compression index as a result of cyclic loading.https://cer.qom.ac.ir/article_3572_f5d890576c7c305d77dd64f5bd3ea6f8.pdfUniversity of QomCivil Infrastructure Researches2783-140X11120250522Development of a Laboratory-Scale Deep Soil Mixing Device for Assessing the Influential Factors on Strength of DSM ColumnsDevelopment of a Laboratory-Scale Deep Soil Mixing Device for Assessing the Influential Factors on Strength of DSM Columns145166346110.22091/cer.2025.12467.1606FAMahdiSafdari Seh GonbadFaculty of Civil Engineering, K.N. Toosi University of Technology, Tehran, Iran.0000-0003-0612-535XMahmood RezaAbdiFaculty of Civil Engineering, K.N. Toosi University of Technology, Tehran, Iran.0000-0002-3473-9677Journal Article20250301The wide range of applications of deep soil mixing has attracted the attention of many researchers to this ground improvement method. Although large-scale field tests are known as the most reliable method for investigating the strength characteristics of DSM columns, the high cost and time-consuming nature of these tests are challenging. To overcome these issues, some researchers have utilized laboratory-scale deep soil mixing devices. However, limited information is available on the design and construction of these apparatuses. Enhancing knowledge in the design and manufacture of this equipment will eliminate the weaknesses of previous devices, increase the capabilities of future apparatuses, optimize construction time and cost, expand studies related to the deep soil mixing method, and ultimately raise awareness of this ground improvement technique. Therefore, this study first fully describes the development of a laboratory-scale deep soil mixing device. Then, the compressive strength of two groups of small-scale DSM columns, both constructed using the developed device and having the same dimensions and installation method, was investigated. The first group had identical cement content and water/cement ratio, while these factors varied in the second group. The low strength variability and good mixing quality of the first group confirmed the performance and accuracy of the developed device for constructing DSM columns. Strength evaluation of the second group showed that by reducing the water/cement ratio and increasing the cement content, the compressive strength of the columns increased. The wide range of applications of deep soil mixing has attracted the attention of many researchers to this ground improvement method. Although large-scale field tests are known as the most reliable method for investigating the strength characteristics of DSM columns, the high cost and time-consuming nature of these tests are challenging. To overcome these issues, some researchers have utilized laboratory-scale deep soil mixing devices. However, limited information is available on the design and construction of these apparatuses. Enhancing knowledge in the design and manufacture of this equipment will eliminate the weaknesses of previous devices, increase the capabilities of future apparatuses, optimize construction time and cost, expand studies related to the deep soil mixing method, and ultimately raise awareness of this ground improvement technique. Therefore, this study first fully describes the development of a laboratory-scale deep soil mixing device. Then, the compressive strength of two groups of small-scale DSM columns, both constructed using the developed device and having the same dimensions and installation method, was investigated. The first group had identical cement content and water/cement ratio, while these factors varied in the second group. The low strength variability and good mixing quality of the first group confirmed the performance and accuracy of the developed device for constructing DSM columns. Strength evaluation of the second group showed that by reducing the water/cement ratio and increasing the cement content, the compressive strength of the columns increased. https://cer.qom.ac.ir/article_3461_e7a5cfbbabff67ac9d2c7c3c32dd857a.pdfUniversity of QomCivil Infrastructure Researches2783-140X11120250522Experimental Evaluation of Seismic Performance of Pile-to-Deck Connections: A Case Study of Common Pile Caps in IranExperimental Evaluation of Seismic Performance of Pile-to-Deck Connections: A Case Study of Common Pile Caps in Iran167183361610.22091/cer.2025.12047.1592FARouhollahPourmirzaDepartment of Civil Engineering, Faculty of Engineering, University of Qom, Qom, Iran0009-0002-8401-8357RouhollahAmirabadiDepartment of Civil Engineering, Faculty of Engineering, University of Qom, Qom, Iran0000-0003-3953-7246MahdiSharifiDepartment of Civil Engineering, Faculty of Engineering, University of Qom, Qom, Iran0000-0001-8166-1668Journal Article20250312This study investigates the seismic behavior and experimental analysis of two common types of pile caps used in infrastructure projects for port construction in Iran. The objective of this research is to evaluate the mechanical and energy performance of these pile caps under cyclic loading, particularly in the pile-to-deck connection regions. Two pile cap samples, namely PRC and PEST, were subjected to bending and shear loads in laboratory conditions. The results revealed that the PRC sample experienced reinforcement yielding and concrete cover cracking under similar loading conditions, whereas the PEST sample failed primarily at the welding joint between the pile and deck bolt connection. Additionally, compared to the PRC sample, the PEST sample exhibited higher stiffness, attributed to the use of steel pipes and grout in its construction. On the other hand, the energy absorption capacity and hysteretic damping in the PRC sample were higher, especially at higher drifts, than in the PEST sample. These findings have direct implications for the design and performance of port structures under seismic loads. The results of this study can contribute to improving the design of pile-to-deck connections and enhancing the performance of structures against seismic forces.This study investigates the seismic behavior and experimental analysis of two common types of pile caps used in infrastructure projects for port construction in Iran. The objective of this research is to evaluate the mechanical and energy performance of these pile caps under cyclic loading, particularly in the pile-to-deck connection regions. Two pile cap samples, namely PRC and PEST, were subjected to bending and shear loads in laboratory conditions. The results revealed that the PRC sample experienced reinforcement yielding and concrete cover cracking under similar loading conditions, whereas the PEST sample failed primarily at the welding joint between the pile and deck bolt connection. Additionally, compared to the PRC sample, the PEST sample exhibited higher stiffness, attributed to the use of steel pipes and grout in its construction. On the other hand, the energy absorption capacity and hysteretic damping in the PRC sample were higher, especially at higher drifts, than in the PEST sample. These findings have direct implications for the design and performance of port structures under seismic loads. The results of this study can contribute to improving the design of pile-to-deck connections and enhancing the performance of structures against seismic forces.https://cer.qom.ac.ir/article_3616_63e160c7f87066c59002cf0788d5740d.pdfUniversity of QomCivil Infrastructure Researches2783-140X11120250522Investigation of the Combined Effect of Nano Copper Oxide and Polypro-Pylene Fibers in Asphalt Mixtures to Prevent RuttingInvestigation of the Combined Effect of Nano Copper Oxide and Polypro-Pylene Fibers in Asphalt Mixtures to Prevent Rutting185201332810.22091/cer.2025.11451.1582FARezaJalalkamaliDepartment of Civil Engineering, Faculty of Engineering, Shahid Bahonar University of Kerman, Kerman, Iran.0000-0002-6750-847XNimaRoostaDepartment of Civil Engineering, Faculty of Engineering, Shahid Bahonar University of Kerman, Kerman, Iran.0009-0002-0990-915XMohammad HossainJalal KamaliDepartment of Civil and Mining Engineering, University of Gonabad, Razavi Khorasan, Iran.0000-0001-7897-0056Journal Article20241008Rutting is one of the most common failures in asphalt pavements, typically caused by inadequate compaction, loss of materials, or insufficient shear resistance of the asphalt mixture. In this study, the effect of combining nano-copper oxide and polypropylene fibers on improving the resistance of asphalt mixtures to rutting was investigated. First, the optimal percentage of nano-copper oxide was determined using resilient modulus and dynamic creep tests. The results showed that adding 2% nano-copper oxide increased the resilient modulus of the asphalt mixture by up to 50%. Subsequently, 0.1, 0.3 and 0.5% polypropylene fibers were added to the asphalt mixture containing 2% nano-copper oxide. The results indicated that adding 0.3% polypropylene fibers improved the Marshall stability of the asphalt mixture by up to 5.2%. However, increasing the fiber content beyond 0.3% negatively impacted the Marshall stability due to reduced adhesion between the bitumen and aggregate. Additionally, the addition of polypropylene fibers decreased the Marshall flow of the asphalt mixture. Nano-copper oxide alone also increased the flow of the mixture. Overall, the combination of 2% nano-copper oxide and 0.3% polypropylene fibers increased the resistance of the asphalt mixture by up to 8.1% and created a balance between flow and stiffness. These results suggest that the simultaneous use of these two additives can be an effective solution for enhancing the performance of asphalt mixtures against rutting and improving mechanical resistance.Rutting is one of the most common failures in asphalt pavements, typically caused by inadequate compaction, loss of materials, or insufficient shear resistance of the asphalt mixture. In this study, the effect of combining nano-copper oxide and polypropylene fibers on improving the resistance of asphalt mixtures to rutting was investigated. First, the optimal percentage of nano-copper oxide was determined using resilient modulus and dynamic creep tests. The results showed that adding 2% nano-copper oxide increased the resilient modulus of the asphalt mixture by up to 50%. Subsequently, 0.1, 0.3 and 0.5% polypropylene fibers were added to the asphalt mixture containing 2% nano-copper oxide. The results indicated that adding 0.3% polypropylene fibers improved the Marshall stability of the asphalt mixture by up to 5.2%. However, increasing the fiber content beyond 0.3% negatively impacted the Marshall stability due to reduced adhesion between the bitumen and aggregate. Additionally, the addition of polypropylene fibers decreased the Marshall flow of the asphalt mixture. Nano-copper oxide alone also increased the flow of the mixture. Overall, the combination of 2% nano-copper oxide and 0.3% polypropylene fibers increased the resistance of the asphalt mixture by up to 8.1% and created a balance between flow and stiffness. These results suggest that the simultaneous use of these two additives can be an effective solution for enhancing the performance of asphalt mixtures against rutting and improving mechanical resistance.https://cer.qom.ac.ir/article_3328_86d60f73a1d0a26832d5961316a5ced8.pdfUniversity of QomCivil Infrastructure Researches2783-140X11120250522In-plane Behavior of Steel Frames with Various Infill Materials; A Parametric Finite Element StudyIn-plane Behavior of Steel Frames with Various Infill Materials; A Parametric Finite Element Study203215358010.22091/cer.2025.11867.1587FAHamzehOmidvarDepartment of Civil Engineering, Faculty of Engineering, Arak University, Arak, Iran0009-0008-1232-9213Seyed JafarHashemiDepartment of Civil Engineering, Faculty of Engineering, Arak University, Arak, Iran0000-0003-0528-2572MahdiYazdaniDepartment of Civil Engineering, Faculty of Engineering, Arak University, Arak, Iran0000-0001-8574-9667Journal Article20241208With development of new technologies in recent years, traditional masonry infills have gradually been replaced by modern one like Concrete Sandwich Panels (CSP). In the present paper, the seismic in-plane behavior of steel frame infilled with CSP has been compared with masonry-infilled frames. To this end, two widely used masonry infill types, i.e. clay brick and Autoclaved Aerated Concrete (AAC) block, were selected to investigate and compare with the behavior of CSP-infilled steel frames. First, numerical models were created through finite element (FE) method and then validated against experimental results for single bay bare and infilled frames. Afterwards, by considering the factors affecting the lateral behavior of infilled frames, i.e. the infill material, aspect ratio and number of spans, a parametric study was carried out on the infilled frames. The results showed that the steel frame infilled with CSP has higher initial stiffness and maximum lateral strength than masonry-infilled frames. The initial stiffness of the infilled frame with CSP was computed to be 1.90 and 2.95 times that of the steel frame infilled with brick and AAC block, respectively. Also, the maximum lateral strength of the CSP-infilled frame was 1.48 and 1.80 times, respectively, of the frame with brick and AAC block. The results of infilled frames with various aspect ratios displayed that the effect of increasing the span length on the in-plane behavior of the CSP-infilled frame is more significant than that of the masonry models.With development of new technologies in recent years, traditional masonry infills have gradually been replaced by modern one like Concrete Sandwich Panels (CSP). In the present paper, the seismic in-plane behavior of steel frame infilled with CSP has been compared with masonry-infilled frames. To this end, two widely used masonry infill types, i.e. clay brick and Autoclaved Aerated Concrete (AAC) block, were selected to investigate and compare with the behavior of CSP-infilled steel frames. First, numerical models were created through finite element (FE) method and then validated against experimental results for single bay bare and infilled frames. Afterwards, by considering the factors affecting the lateral behavior of infilled frames, i.e. the infill material, aspect ratio and number of spans, a parametric study was carried out on the infilled frames. The results showed that the steel frame infilled with CSP has higher initial stiffness and maximum lateral strength than masonry-infilled frames. The initial stiffness of the infilled frame with CSP was computed to be 1.90 and 2.95 times that of the steel frame infilled with brick and AAC block, respectively. Also, the maximum lateral strength of the CSP-infilled frame was 1.48 and 1.80 times, respectively, of the frame with brick and AAC block. The results of infilled frames with various aspect ratios displayed that the effect of increasing the span length on the in-plane behavior of the CSP-infilled frame is more significant than that of the masonry models.https://cer.qom.ac.ir/article_3580_aba5ed8874a3e75272a93259458ceeee.pdf