Journal of Civil Engineering Researchers (original) (raw)
Papers by Journal of Civil Engineering Researchers
Namā, Mar 28, 2024
Nanotechnology has emerged as a transformative force in the construction industry, revolutionizin... more Nanotechnology has emerged as a transformative force in the construction industry, revolutionizing traditional building materials and methods. This paper delves into the multifaceted applications of nanotechnology in construction, focusing on its impact on building coatings, materials, colors, insulation, and sensors. By incorporating nanoparticles like carbon nanotubes and titanium dioxide, construction materials gain enhanced mechanical properties and durability. Nano-coatings applied to surfaces such as glass, wood, and concrete offer benefits like water repellence, UV resistance, and antibacterial properties, contributing to energy efficiency and cost savings. Furthermore, advancements in selfhealing concrete, fire-resistant glass, and smart surfaces demonstrate the potential of nanotechnology to address longstanding challenges in construction. The paper also explores the use of nanotechnology in paints, insulation, and sensors, highlighting innovations such as self-cleaning paints, antistatic coatings, and nano-acoustic insulators. Overall, the integration of nanotechnology into the construction sector promises improved product quality, energy efficiency, and longevity, heralding a new era of sustainable and resilient built environments.
Namā, Mar 28, 2024
Floods are natural disasters that can result in significant social, economic, and environmental i... more Floods are natural disasters that can result in significant social, economic, and environmental impacts. Timely and accurate flood detection is crucial for effective disaster management and mitigation. This paper addresses the importance of water segmentation in flood detection and water engineering applications, emphasizing the need for precise delineation of water areas in flood-hit regions. Accurate water segmentation not only aids in assessing the extent of flooding but also plays a vital role in predicting and preventing potential flood events. This study explores the application of advanced deep learning models, namely SegNet, UNet, and FCN32 for automated flood area segmentation. Leveraging a dataset comprising 290 images depicting flood-affected areas, the models are trained to accurately delineate water regions within the images. The experiment results demonstrate the efficacy of these models in effectively segmenting floodwaters. Among the tested models, SegNet emerges as the top performer, achieving an impressive precision rate of 88%. This superior performance underscores the potential of deep learning techniques in enhancing flood detection and response capabilities, paving the way for more efficient and reliable flood prediction systems.
Namā, Apr 21, 2024
Due to the important role that bridges play in rescue operations after an earthquake, it is neces... more Due to the important role that bridges play in rescue operations after an earthquake, it is necessary that these structures have a higher level of protection against seismic attacks. Earthquake identifies the weak points of the structure and causes the most damage there. Bridges are very vulnerable to these attacks due to their low degree of uncertainty. All bridges built before 1971 were designed with the elastic design method (permissible stress). In this method, the effects of plasticity, section cracking, and plastic deformation are not taken into account. The change of seismic locations based on the principles of elastic design is much less. It is because the structure experiences in a real earthquake, one of the consequences of which is the falling of the decks due to the loss of the support surface. The decision to strengthen the bridge was made when there were many bending and shear cracks on the king beams. The bridge was created. The use of FRP profiles can significantly prevent the damage caused by corrosion and is a good alternative to the traditional methods of strengthening the structure. In this study, a design for the deck of a steel bridge with I beams is presented. The shape of reinforcement using FRP fibers with vinyl ester resins has also been investigated, the effect of the geometry of FRP profiles has been investigated. The presented specifications are optimized to obtain a lasting shape and section, especially for the pultrusion process. FRP materials are light, resistant to corrosion and have high tensile strength. These materials come in different forms and range from multi-layer factory sheets to dry sheets that can be twisted on various structural forms before adding resin, is available. The durability and high tensile strength of FRP materials are among the advantages of these materials. The durability and long-term performance of FRP requires more research, which is ongoing and continues.
Journal of Civil Engineering Researchers, Oct 28, 2023
Seismic Strengthening offers a cost-effective and sustainable solution for constructing bridges i... more Seismic Strengthening offers a cost-effective and sustainable solution for constructing bridges in seismic zones. In these rehabilitation interventions, Fiber Reinforced Polymer (FRP) composites are often used instead of steel members due to their lightweight nature, high strength, and excellent corrosion resistance. Researchers are now focusing on creating innovative FRPconcrete hybrid structures. This study specifically investigates the numerical modeling of the response of a hybrid FRP-concrete jacket bridge pier subjected to quasi-static tests. The Finite Element Method (FEM) results demonstrated a significant correlation with the experimental response, particularly in terms of the load-displacement curve failure mode. Once the model was validated, various alternative designs were numerically tested to evaluate the impact of each model on the load-bearing capacity. These designs included altering the height of the CFRP sheet, adjusting the height and congestion of the CFRP bar, and comparing the performance of the concrete jacket with and without the CFRP sheet. After reinforcing the CFRP sheets and incorporating Near-Surface-Mounted (NSM)-CFRP bars, the reinforcement system, along with the new concrete jacket, effectively transferred the integrity of the broken pier area and maintained a constant load-bearing capacity for the bridge pier. However, when the CFRP sheet was added to the aforementioned system, the load capacity of the bridge pier increased by more than 60%. Therefore, it can be concluded that seismic enhancement techniques utilizing CFRP sheets and mounted NSM-CFRP bars are successful in enhancing the strength and resilience of the concrete bridge pier.
Journal of Civil Engineering Researchers, Oct 28, 2023
Flood drainage ditches serve as critical infrastructure, directing and managing floodwaters to pr... more Flood drainage ditches serve as critical infrastructure, directing and managing floodwaters to prevent indiscriminate flow, reduce flooding risks, and curb erosion. Vegetation plays a crucial role in enhancing the effectiveness of these ditches. It acts as a natural barrier, mitigating floodwater speed and impact while stabilizing soil and preventing erosion. Furthermore, vegetation aids in water quality improvement by filtering pollutants and nutrients, making it safer for humans, animals, and plants. It also reduces peak flows and attenuates floodwaters, thereby minimizing urban flooding risks. Additionally, the presence of vegetation in floodplains provides extra storage capacity for excess water, supporting floodplain management and biodiversity conservation. The study emphasizes the importance of carefully considering vegetation type, characteristics, and management practices to optimize flood drainage ditch performance. Selection of suitable plant species and morphological optimization significantly enhances drainage capacity and infiltration rates. Proper maintenance and management practices are vital to ensure unimpeded water flow and prevent obstruction.
Namā, Mar 28, 2024
In this study, geopolymer concrete made from fly ash was utilized, with different proportions of ... more In this study, geopolymer concrete made from fly ash was utilized, with different proportions of cement (0%, 10%, and 20%) replacing fly ash to examine the influence of cement presence in geopolymer concrete. To increase tensile strength and impact resistance, 0.5 and 1 percent steel fibers were used. Adding 0.5 percent fibers improved compressive strength by 9 percent, and for 1 percent fibers, it was 26 percent. The tensile strength also significantly increased with the addition of fibers. Adding 0.5% fibers, on average, increased the tensile strength by 25%, with the increase being 34% for 1% fibers. It was also noted that substituting cement for fly ash had little effect on compressive strength, but replacing 10% cement could be considered as the optimal substitution level in terms of tensile strength in the samples. The test results for impact resistance indicated a significant effect of steel fibers on the number of impacts until the first crack appeared and the complete rupture of the samples. Adding fibers increased the resistance to complete rupture by 12 to 22 percent with 0.5 percent fibers, and between 49 to 64 percent for 1 percent fibers. Replacing 10 percent rubber crumbs improved the impact energy of concrete, increasing the energy until the first crack by 10 percent on average and the energy until complete rupture by 15 percent.
Sigma mühendislik ve fen bilimleri dergisi, 2024
Ductile end diaphragms have been suggested as an appropriate device in the past to improve the se... more Ductile end diaphragms have been suggested as an appropriate device in the past to improve the seismic response of steel girder bridges. This paper investigates the efficiency of the seismic design strategy that utilized a slab-connected steel plate as a ductile diaphragm in the superstructure. Protecting the main girder from typically reported damage and mitigating the transferred lateral load to the non-ductile substructures are the main objectives of this study. The results show that a slab-connected thin steel plate with low yielding stress (LYS) can mitigate the force demand on the non-ductile substructures and act as a structural fuse. It can also reduce the transverse displacement of the superstructure and, consequently, prevent the end of the main girder from buckling and/or yielding. Cite this article as: Jamshidi M. LYS semi-supported plate as a ductile end-diaphragm in steel girder bridges.
Nanotechnology has emerged as a transformative force in the construction industry, revolutionizin... more Nanotechnology has emerged as a transformative force in the construction industry, revolutionizing traditional building materials and methods. This paper delves into the multifaceted applications of nanotechnology in construction, focusing on its impact on building coatings, materials, colors, insulation, and sensors. By incorporating nanoparticles like carbon nanotubes and titanium dioxide, construction materials gain enhanced mechanical properties and durability. Nano-coatings applied to surfaces such as glass, wood, and concrete offer benefits like water repellence, UV resistance, and antibacterial properties, contributing to energy efficiency and cost savings. Furthermore, advancements in selfhealing concrete, fire-resistant glass, and smart surfaces demonstrate the potential of nanotechnology to address longstanding challenges in construction. The paper also explores the use of nanotechnology in paints, insulation, and sensors, highlighting innovations such as self-cleaning paints, antistatic coatings, and nano-acoustic insulators. Overall, the integration of nanotechnology into the construction sector promises improved product quality, energy efficiency, and longevity, heralding a new era of sustainable and resilient built environments.
In this study, geopolymer concrete made from fly ash was utilized, with different proportions of ... more In this study, geopolymer concrete made from fly ash was utilized, with different proportions of cement (0%, 10%, and 20%) replacing fly ash to examine the influence of cement presence in geopolymer concrete. To increase tensile strength and impact resistance, 0.5 and 1 percent steel fibers were used. Adding 0.5 percent fibers improved compressive strength by 9 percent, and for 1 percent fibers, it was 26 percent. The tensile strength also significantly increased with the addition of fibers. Adding 0.5% fibers, on average, increased the tensile strength by 25%, with the increase being 34% for 1% fibers. It was also noted that substituting cement for fly ash had little effect on compressive strength, but replacing 10% cement could be considered as the optimal substitution level in terms of tensile strength in the samples. The test results for impact resistance indicated a significant effect of steel fibers on the number of impacts until the first crack appeared and the complete rupture of the samples. Adding fibers increased the resistance to complete rupture by 12 to 22 percent with 0.5 percent fibers, and between 49 to 64 percent for 1 percent fibers. Replacing 10 percent rubber crumbs improved the impact energy of concrete, increasing the energy until the first crack by 10 percent on average and the energy until complete rupture by 15 percent.
Journals&Researcher, 2024
Due to the important role that bridges play in rescue operations after an earthquake, it is neces... more Due to the important role that bridges play in rescue operations after an earthquake, it is necessary that these structures have a higher level of protection against seismic attacks. Earthquake identifies the weak points of the structure and causes the most damage there. Bridges are very vulnerable to these attacks due to their low degree of uncertainty. All bridges built before 1971 were designed with the elastic design method (permissible stress). In this method, the effects of plasticity, section cracking, and plastic deformation are not taken into account. The change of seismic locations based on the principles of elastic design is much less. It is because the structure experiences in a real earthquake, one of the consequences of which is the falling of the decks due to the loss of the support surface. The decision to strengthen the bridge was made when there were many bending and shear cracks on the king beams. The bridge was created. The use of FRP profiles can significantly prevent the damage caused by corrosion and is a good alternative to the traditional methods of strengthening the structure. In this study, a design for the deck of a steel bridge with I beams is presented. The shape of reinforcement using FRP fibers with vinyl ester resins has also been investigated, the effect of the geometry of FRP profiles has been investigated. The presented specifications are optimized to obtain a lasting shape and section, especially for the pultrusion process. FRP materials are light, resistant to corrosion and have high tensile strength. These materials come in different forms and range from multi-layer factory sheets to dry sheets that can be twisted on various structural forms before adding resin, is available. The durability and high tensile strength of FRP materials are among the advantages of these materials. The durability and long-term performance of FRP requires more research, which is ongoing and continues.
Journal of Civil Engineering Researchers , 2024
Floods are natural disasters that can result in significant social, economic, and environmental i... more Floods are natural disasters that can result in significant social, economic, and environmental impacts. Timely and accurate flood detection is crucial for effective disaster management and mitigation. This paper addresses the importance of water segmentation in flood detection and water engineering applications, emphasizing the need for precise delineation of water areas in flood-hit regions. Accurate water segmentation not only aids in assessing the extent of flooding but also plays a vital role in predicting and preventing potential flood events. This study explores the application of advanced deep learning models, namely SegNet, UNet, and FCN32 for automated flood area segmentation. Leveraging a dataset comprising 290 images depicting flood-affected areas, the models are trained to accurately delineate water regions within the images. The experiment results demonstrate the efficacy of these models in effectively segmenting floodwaters. Among the tested models, SegNet emerges as the top performer, achieving an impressive precision rate of 88%. This superior performance underscores the potential of deep learning techniques in enhancing flood detection and response capabilities, paving the way for more efficient and reliable flood prediction systems.
Journal of Civil Engineering Researchers , 2023
Nanotechnology is poised to offer a viable solution for achieving high performance in future cons... more Nanotechnology is poised to offer a viable solution for achieving high performance in future construction projects. Among the innovative technologies being explored, smart concrete has garnered significant attention and undergone extensive research in reputable scientific centers worldwide in recent years. A notable advancement within this field is the development of selfhealing concrete. Concrete structures are undeniably susceptible to cracking, primarily due to natural processes. These cracks serve as pathways for harmful substances to infiltrate and corrode the reinforcement bars, ultimately leading to the degradation of the concrete. Traditional approaches to address this issue involve the use of repair materials, particularly various polymers. However, these materials not only complicate the repair process but also have adverse environmental consequences. In light of these challenges, scientists have discovered an alternative method that involves incorporating bacteria into concrete production to create self-healing properties. This method not only reduces maintenance and repair costs but also minimizes environmental impact, thereby enhancing the durability and performance of the concrete while extending its service life. By harnessing the power of bacteria, self-healing concrete represents a significant breakthrough in sustainable construction practices.
Journal of Civil Engineering Researchers , 2024
In the use of non-linear structural performance models, including models that consider the critic... more In the use of non-linear structural performance models, including models that consider the critical over-performance at the failure stage, is very important when performing seismic calculations of reinforced concrete buildings and structures.The use of such models is especially important if the structures have primary damage caused by fire or corrosion, as well as mechanical damage caused by force factors. The purpose of this study is to develop an analytical model of the deformation of eccentrically compressed reinforced concrete columns by considering the failure stage, which includes processes such as peeling of the protective layer, reduction of the stability of the compressed reinforcement and softening of the encased concrete after reaching the design strength. , the existing models that describe the residual behavior of reinforced concrete structures under low cycle loading have been investigated. The models are analyzed considering monotonic curves, which are cyclic deformation boundaries. The model proposed in the research is constructed by analyzing the stages of the stress-strain state of a reinforced concrete column. At each stage, formulas are found for determining moment and curvature by solving equations of equilibrium of internal forces. Calculations based on the obtained model for a particular reinforced concrete column are carried out, monotonous diagrams are obtained, and a conclusion about the significant influence of the level of axial load on the character of deformation is made. On the basis of the obtained model, the construction of hysteresis diagrams under low-cycle loading is expected in the future.
Journal of Civil Engineering Researchers , 2023
Flood drainage ditches serve as critical infrastructure, directing and managing floodwaters to pr... more Flood drainage ditches serve as critical infrastructure, directing and managing floodwaters to prevent indiscriminate flow, reduce flooding risks, and curb erosion. Vegetation plays a crucial role in enhancing the effectiveness of these ditches. It acts as a natural barrier, mitigating floodwater speed and impact while stabilizing soil and preventing erosion. Furthermore, vegetation aids in water quality improvement by filtering pollutants and nutrients, making it safer for humans, animals, and plants. It also reduces peak flows and attenuates floodwaters, thereby minimizing urban flooding risks. Additionally, the presence of vegetation in floodplains provides extra storage capacity for excess water, supporting floodplain management and biodiversity conservation. The study emphasizes the importance of carefully considering vegetation type, characteristics, and management practices to optimize flood drainage ditch performance. Selection of suitable plant species and morphological optimization significantly enhances drainage capacity and infiltration rates. Proper maintenance and management practices are vital to ensure unimpeded water flow and prevent obstruction.
Flood drainage ditches serve as critical infrastructure, directing and managing floodwaters to pr... more Flood drainage ditches serve as critical infrastructure, directing and managing floodwaters to prevent indiscriminate flow, reduce flooding risks, and curb erosion. Vegetation plays a crucial role in enhancing the effectiveness of these ditches. It acts as a natural barrier, mitigating floodwater speed and impact while stabilizing soil and preventing erosion. Furthermore, vegetation aids in water quality improvement by filtering pollutants and nutrients, making it safer for humans, animals, and plants. It also reduces peak flows and attenuates floodwaters, thereby minimizing urban flooding risks. Additionally, the presence of vegetation in floodplains provides extra storage capacity for excess water, supporting floodplain management and biodiversity conservation. The study emphasizes the importance of carefully considering vegetation type, characteristics, and management practices to optimize flood drainage ditch performance. Selection of suitable plant species and morphological optimization significantly enhances drainage capacity and infiltration rates. Proper maintenance and management practices are vital to ensure unimpeded water flow and prevent obstruction.
Journal of Civil Engineering Researchers , 2033
Seismic Strengthening offers a cost-effective and sustainable solution for constructing bridges i... more Seismic Strengthening offers a cost-effective and sustainable solution for constructing bridges in seismic zones. In these rehabilitation interventions, Fiber Reinforced Polymer (FRP) composites are often used instead of steel members due to their lightweight nature, high strength, and excellent corrosion resistance. Researchers are now focusing on creating innovative FRPconcrete hybrid structures. This study specifically investigates the numerical modeling of the response of a hybrid FRP-concrete jacket bridge pier subjected to quasi-static tests. The Finite Element Method (FEM) results demonstrated a significant correlation with the experimental response, particularly in terms of the load-displacement curve failure mode. Once the model was validated, various alternative designs were numerically tested to evaluate the impact of each model on the load-bearing capacity. These designs included altering the height of the CFRP sheet, adjusting the height and congestion of the CFRP bar, and comparing the performance of the concrete jacket with and without the CFRP sheet. After reinforcing the CFRP sheets and incorporating Near-Surface-Mounted (NSM)-CFRP bars, the reinforcement system, along with the new concrete jacket, effectively transferred the integrity of the broken pier area and maintained a constant load-bearing capacity for the bridge pier. However, when the CFRP sheet was added to the aforementioned system, the load capacity of the bridge pier increased by more than 60%. Therefore, it can be concluded that seismic enhancement techniques utilizing CFRP sheets and mounted NSM-CFRP bars are successful in enhancing the strength and resilience of the concrete bridge pier.
Namā, Mar 28, 2024
Nanotechnology has emerged as a transformative force in the construction industry, revolutionizin... more Nanotechnology has emerged as a transformative force in the construction industry, revolutionizing traditional building materials and methods. This paper delves into the multifaceted applications of nanotechnology in construction, focusing on its impact on building coatings, materials, colors, insulation, and sensors. By incorporating nanoparticles like carbon nanotubes and titanium dioxide, construction materials gain enhanced mechanical properties and durability. Nano-coatings applied to surfaces such as glass, wood, and concrete offer benefits like water repellence, UV resistance, and antibacterial properties, contributing to energy efficiency and cost savings. Furthermore, advancements in selfhealing concrete, fire-resistant glass, and smart surfaces demonstrate the potential of nanotechnology to address longstanding challenges in construction. The paper also explores the use of nanotechnology in paints, insulation, and sensors, highlighting innovations such as self-cleaning paints, antistatic coatings, and nano-acoustic insulators. Overall, the integration of nanotechnology into the construction sector promises improved product quality, energy efficiency, and longevity, heralding a new era of sustainable and resilient built environments.
Namā, Mar 28, 2024
Floods are natural disasters that can result in significant social, economic, and environmental i... more Floods are natural disasters that can result in significant social, economic, and environmental impacts. Timely and accurate flood detection is crucial for effective disaster management and mitigation. This paper addresses the importance of water segmentation in flood detection and water engineering applications, emphasizing the need for precise delineation of water areas in flood-hit regions. Accurate water segmentation not only aids in assessing the extent of flooding but also plays a vital role in predicting and preventing potential flood events. This study explores the application of advanced deep learning models, namely SegNet, UNet, and FCN32 for automated flood area segmentation. Leveraging a dataset comprising 290 images depicting flood-affected areas, the models are trained to accurately delineate water regions within the images. The experiment results demonstrate the efficacy of these models in effectively segmenting floodwaters. Among the tested models, SegNet emerges as the top performer, achieving an impressive precision rate of 88%. This superior performance underscores the potential of deep learning techniques in enhancing flood detection and response capabilities, paving the way for more efficient and reliable flood prediction systems.
Namā, Apr 21, 2024
Due to the important role that bridges play in rescue operations after an earthquake, it is neces... more Due to the important role that bridges play in rescue operations after an earthquake, it is necessary that these structures have a higher level of protection against seismic attacks. Earthquake identifies the weak points of the structure and causes the most damage there. Bridges are very vulnerable to these attacks due to their low degree of uncertainty. All bridges built before 1971 were designed with the elastic design method (permissible stress). In this method, the effects of plasticity, section cracking, and plastic deformation are not taken into account. The change of seismic locations based on the principles of elastic design is much less. It is because the structure experiences in a real earthquake, one of the consequences of which is the falling of the decks due to the loss of the support surface. The decision to strengthen the bridge was made when there were many bending and shear cracks on the king beams. The bridge was created. The use of FRP profiles can significantly prevent the damage caused by corrosion and is a good alternative to the traditional methods of strengthening the structure. In this study, a design for the deck of a steel bridge with I beams is presented. The shape of reinforcement using FRP fibers with vinyl ester resins has also been investigated, the effect of the geometry of FRP profiles has been investigated. The presented specifications are optimized to obtain a lasting shape and section, especially for the pultrusion process. FRP materials are light, resistant to corrosion and have high tensile strength. These materials come in different forms and range from multi-layer factory sheets to dry sheets that can be twisted on various structural forms before adding resin, is available. The durability and high tensile strength of FRP materials are among the advantages of these materials. The durability and long-term performance of FRP requires more research, which is ongoing and continues.
Journal of Civil Engineering Researchers, Oct 28, 2023
Seismic Strengthening offers a cost-effective and sustainable solution for constructing bridges i... more Seismic Strengthening offers a cost-effective and sustainable solution for constructing bridges in seismic zones. In these rehabilitation interventions, Fiber Reinforced Polymer (FRP) composites are often used instead of steel members due to their lightweight nature, high strength, and excellent corrosion resistance. Researchers are now focusing on creating innovative FRPconcrete hybrid structures. This study specifically investigates the numerical modeling of the response of a hybrid FRP-concrete jacket bridge pier subjected to quasi-static tests. The Finite Element Method (FEM) results demonstrated a significant correlation with the experimental response, particularly in terms of the load-displacement curve failure mode. Once the model was validated, various alternative designs were numerically tested to evaluate the impact of each model on the load-bearing capacity. These designs included altering the height of the CFRP sheet, adjusting the height and congestion of the CFRP bar, and comparing the performance of the concrete jacket with and without the CFRP sheet. After reinforcing the CFRP sheets and incorporating Near-Surface-Mounted (NSM)-CFRP bars, the reinforcement system, along with the new concrete jacket, effectively transferred the integrity of the broken pier area and maintained a constant load-bearing capacity for the bridge pier. However, when the CFRP sheet was added to the aforementioned system, the load capacity of the bridge pier increased by more than 60%. Therefore, it can be concluded that seismic enhancement techniques utilizing CFRP sheets and mounted NSM-CFRP bars are successful in enhancing the strength and resilience of the concrete bridge pier.
Journal of Civil Engineering Researchers, Oct 28, 2023
Flood drainage ditches serve as critical infrastructure, directing and managing floodwaters to pr... more Flood drainage ditches serve as critical infrastructure, directing and managing floodwaters to prevent indiscriminate flow, reduce flooding risks, and curb erosion. Vegetation plays a crucial role in enhancing the effectiveness of these ditches. It acts as a natural barrier, mitigating floodwater speed and impact while stabilizing soil and preventing erosion. Furthermore, vegetation aids in water quality improvement by filtering pollutants and nutrients, making it safer for humans, animals, and plants. It also reduces peak flows and attenuates floodwaters, thereby minimizing urban flooding risks. Additionally, the presence of vegetation in floodplains provides extra storage capacity for excess water, supporting floodplain management and biodiversity conservation. The study emphasizes the importance of carefully considering vegetation type, characteristics, and management practices to optimize flood drainage ditch performance. Selection of suitable plant species and morphological optimization significantly enhances drainage capacity and infiltration rates. Proper maintenance and management practices are vital to ensure unimpeded water flow and prevent obstruction.
Namā, Mar 28, 2024
In this study, geopolymer concrete made from fly ash was utilized, with different proportions of ... more In this study, geopolymer concrete made from fly ash was utilized, with different proportions of cement (0%, 10%, and 20%) replacing fly ash to examine the influence of cement presence in geopolymer concrete. To increase tensile strength and impact resistance, 0.5 and 1 percent steel fibers were used. Adding 0.5 percent fibers improved compressive strength by 9 percent, and for 1 percent fibers, it was 26 percent. The tensile strength also significantly increased with the addition of fibers. Adding 0.5% fibers, on average, increased the tensile strength by 25%, with the increase being 34% for 1% fibers. It was also noted that substituting cement for fly ash had little effect on compressive strength, but replacing 10% cement could be considered as the optimal substitution level in terms of tensile strength in the samples. The test results for impact resistance indicated a significant effect of steel fibers on the number of impacts until the first crack appeared and the complete rupture of the samples. Adding fibers increased the resistance to complete rupture by 12 to 22 percent with 0.5 percent fibers, and between 49 to 64 percent for 1 percent fibers. Replacing 10 percent rubber crumbs improved the impact energy of concrete, increasing the energy until the first crack by 10 percent on average and the energy until complete rupture by 15 percent.
Sigma mühendislik ve fen bilimleri dergisi, 2024
Ductile end diaphragms have been suggested as an appropriate device in the past to improve the se... more Ductile end diaphragms have been suggested as an appropriate device in the past to improve the seismic response of steel girder bridges. This paper investigates the efficiency of the seismic design strategy that utilized a slab-connected steel plate as a ductile diaphragm in the superstructure. Protecting the main girder from typically reported damage and mitigating the transferred lateral load to the non-ductile substructures are the main objectives of this study. The results show that a slab-connected thin steel plate with low yielding stress (LYS) can mitigate the force demand on the non-ductile substructures and act as a structural fuse. It can also reduce the transverse displacement of the superstructure and, consequently, prevent the end of the main girder from buckling and/or yielding. Cite this article as: Jamshidi M. LYS semi-supported plate as a ductile end-diaphragm in steel girder bridges.
Nanotechnology has emerged as a transformative force in the construction industry, revolutionizin... more Nanotechnology has emerged as a transformative force in the construction industry, revolutionizing traditional building materials and methods. This paper delves into the multifaceted applications of nanotechnology in construction, focusing on its impact on building coatings, materials, colors, insulation, and sensors. By incorporating nanoparticles like carbon nanotubes and titanium dioxide, construction materials gain enhanced mechanical properties and durability. Nano-coatings applied to surfaces such as glass, wood, and concrete offer benefits like water repellence, UV resistance, and antibacterial properties, contributing to energy efficiency and cost savings. Furthermore, advancements in selfhealing concrete, fire-resistant glass, and smart surfaces demonstrate the potential of nanotechnology to address longstanding challenges in construction. The paper also explores the use of nanotechnology in paints, insulation, and sensors, highlighting innovations such as self-cleaning paints, antistatic coatings, and nano-acoustic insulators. Overall, the integration of nanotechnology into the construction sector promises improved product quality, energy efficiency, and longevity, heralding a new era of sustainable and resilient built environments.
In this study, geopolymer concrete made from fly ash was utilized, with different proportions of ... more In this study, geopolymer concrete made from fly ash was utilized, with different proportions of cement (0%, 10%, and 20%) replacing fly ash to examine the influence of cement presence in geopolymer concrete. To increase tensile strength and impact resistance, 0.5 and 1 percent steel fibers were used. Adding 0.5 percent fibers improved compressive strength by 9 percent, and for 1 percent fibers, it was 26 percent. The tensile strength also significantly increased with the addition of fibers. Adding 0.5% fibers, on average, increased the tensile strength by 25%, with the increase being 34% for 1% fibers. It was also noted that substituting cement for fly ash had little effect on compressive strength, but replacing 10% cement could be considered as the optimal substitution level in terms of tensile strength in the samples. The test results for impact resistance indicated a significant effect of steel fibers on the number of impacts until the first crack appeared and the complete rupture of the samples. Adding fibers increased the resistance to complete rupture by 12 to 22 percent with 0.5 percent fibers, and between 49 to 64 percent for 1 percent fibers. Replacing 10 percent rubber crumbs improved the impact energy of concrete, increasing the energy until the first crack by 10 percent on average and the energy until complete rupture by 15 percent.
Journals&Researcher, 2024
Due to the important role that bridges play in rescue operations after an earthquake, it is neces... more Due to the important role that bridges play in rescue operations after an earthquake, it is necessary that these structures have a higher level of protection against seismic attacks. Earthquake identifies the weak points of the structure and causes the most damage there. Bridges are very vulnerable to these attacks due to their low degree of uncertainty. All bridges built before 1971 were designed with the elastic design method (permissible stress). In this method, the effects of plasticity, section cracking, and plastic deformation are not taken into account. The change of seismic locations based on the principles of elastic design is much less. It is because the structure experiences in a real earthquake, one of the consequences of which is the falling of the decks due to the loss of the support surface. The decision to strengthen the bridge was made when there were many bending and shear cracks on the king beams. The bridge was created. The use of FRP profiles can significantly prevent the damage caused by corrosion and is a good alternative to the traditional methods of strengthening the structure. In this study, a design for the deck of a steel bridge with I beams is presented. The shape of reinforcement using FRP fibers with vinyl ester resins has also been investigated, the effect of the geometry of FRP profiles has been investigated. The presented specifications are optimized to obtain a lasting shape and section, especially for the pultrusion process. FRP materials are light, resistant to corrosion and have high tensile strength. These materials come in different forms and range from multi-layer factory sheets to dry sheets that can be twisted on various structural forms before adding resin, is available. The durability and high tensile strength of FRP materials are among the advantages of these materials. The durability and long-term performance of FRP requires more research, which is ongoing and continues.
Journal of Civil Engineering Researchers , 2024
Floods are natural disasters that can result in significant social, economic, and environmental i... more Floods are natural disasters that can result in significant social, economic, and environmental impacts. Timely and accurate flood detection is crucial for effective disaster management and mitigation. This paper addresses the importance of water segmentation in flood detection and water engineering applications, emphasizing the need for precise delineation of water areas in flood-hit regions. Accurate water segmentation not only aids in assessing the extent of flooding but also plays a vital role in predicting and preventing potential flood events. This study explores the application of advanced deep learning models, namely SegNet, UNet, and FCN32 for automated flood area segmentation. Leveraging a dataset comprising 290 images depicting flood-affected areas, the models are trained to accurately delineate water regions within the images. The experiment results demonstrate the efficacy of these models in effectively segmenting floodwaters. Among the tested models, SegNet emerges as the top performer, achieving an impressive precision rate of 88%. This superior performance underscores the potential of deep learning techniques in enhancing flood detection and response capabilities, paving the way for more efficient and reliable flood prediction systems.
Journal of Civil Engineering Researchers , 2023
Nanotechnology is poised to offer a viable solution for achieving high performance in future cons... more Nanotechnology is poised to offer a viable solution for achieving high performance in future construction projects. Among the innovative technologies being explored, smart concrete has garnered significant attention and undergone extensive research in reputable scientific centers worldwide in recent years. A notable advancement within this field is the development of selfhealing concrete. Concrete structures are undeniably susceptible to cracking, primarily due to natural processes. These cracks serve as pathways for harmful substances to infiltrate and corrode the reinforcement bars, ultimately leading to the degradation of the concrete. Traditional approaches to address this issue involve the use of repair materials, particularly various polymers. However, these materials not only complicate the repair process but also have adverse environmental consequences. In light of these challenges, scientists have discovered an alternative method that involves incorporating bacteria into concrete production to create self-healing properties. This method not only reduces maintenance and repair costs but also minimizes environmental impact, thereby enhancing the durability and performance of the concrete while extending its service life. By harnessing the power of bacteria, self-healing concrete represents a significant breakthrough in sustainable construction practices.
Journal of Civil Engineering Researchers , 2024
In the use of non-linear structural performance models, including models that consider the critic... more In the use of non-linear structural performance models, including models that consider the critical over-performance at the failure stage, is very important when performing seismic calculations of reinforced concrete buildings and structures.The use of such models is especially important if the structures have primary damage caused by fire or corrosion, as well as mechanical damage caused by force factors. The purpose of this study is to develop an analytical model of the deformation of eccentrically compressed reinforced concrete columns by considering the failure stage, which includes processes such as peeling of the protective layer, reduction of the stability of the compressed reinforcement and softening of the encased concrete after reaching the design strength. , the existing models that describe the residual behavior of reinforced concrete structures under low cycle loading have been investigated. The models are analyzed considering monotonic curves, which are cyclic deformation boundaries. The model proposed in the research is constructed by analyzing the stages of the stress-strain state of a reinforced concrete column. At each stage, formulas are found for determining moment and curvature by solving equations of equilibrium of internal forces. Calculations based on the obtained model for a particular reinforced concrete column are carried out, monotonous diagrams are obtained, and a conclusion about the significant influence of the level of axial load on the character of deformation is made. On the basis of the obtained model, the construction of hysteresis diagrams under low-cycle loading is expected in the future.
Journal of Civil Engineering Researchers , 2023
Flood drainage ditches serve as critical infrastructure, directing and managing floodwaters to pr... more Flood drainage ditches serve as critical infrastructure, directing and managing floodwaters to prevent indiscriminate flow, reduce flooding risks, and curb erosion. Vegetation plays a crucial role in enhancing the effectiveness of these ditches. It acts as a natural barrier, mitigating floodwater speed and impact while stabilizing soil and preventing erosion. Furthermore, vegetation aids in water quality improvement by filtering pollutants and nutrients, making it safer for humans, animals, and plants. It also reduces peak flows and attenuates floodwaters, thereby minimizing urban flooding risks. Additionally, the presence of vegetation in floodplains provides extra storage capacity for excess water, supporting floodplain management and biodiversity conservation. The study emphasizes the importance of carefully considering vegetation type, characteristics, and management practices to optimize flood drainage ditch performance. Selection of suitable plant species and morphological optimization significantly enhances drainage capacity and infiltration rates. Proper maintenance and management practices are vital to ensure unimpeded water flow and prevent obstruction.
Flood drainage ditches serve as critical infrastructure, directing and managing floodwaters to pr... more Flood drainage ditches serve as critical infrastructure, directing and managing floodwaters to prevent indiscriminate flow, reduce flooding risks, and curb erosion. Vegetation plays a crucial role in enhancing the effectiveness of these ditches. It acts as a natural barrier, mitigating floodwater speed and impact while stabilizing soil and preventing erosion. Furthermore, vegetation aids in water quality improvement by filtering pollutants and nutrients, making it safer for humans, animals, and plants. It also reduces peak flows and attenuates floodwaters, thereby minimizing urban flooding risks. Additionally, the presence of vegetation in floodplains provides extra storage capacity for excess water, supporting floodplain management and biodiversity conservation. The study emphasizes the importance of carefully considering vegetation type, characteristics, and management practices to optimize flood drainage ditch performance. Selection of suitable plant species and morphological optimization significantly enhances drainage capacity and infiltration rates. Proper maintenance and management practices are vital to ensure unimpeded water flow and prevent obstruction.
Journal of Civil Engineering Researchers , 2033
Seismic Strengthening offers a cost-effective and sustainable solution for constructing bridges i... more Seismic Strengthening offers a cost-effective and sustainable solution for constructing bridges in seismic zones. In these rehabilitation interventions, Fiber Reinforced Polymer (FRP) composites are often used instead of steel members due to their lightweight nature, high strength, and excellent corrosion resistance. Researchers are now focusing on creating innovative FRPconcrete hybrid structures. This study specifically investigates the numerical modeling of the response of a hybrid FRP-concrete jacket bridge pier subjected to quasi-static tests. The Finite Element Method (FEM) results demonstrated a significant correlation with the experimental response, particularly in terms of the load-displacement curve failure mode. Once the model was validated, various alternative designs were numerically tested to evaluate the impact of each model on the load-bearing capacity. These designs included altering the height of the CFRP sheet, adjusting the height and congestion of the CFRP bar, and comparing the performance of the concrete jacket with and without the CFRP sheet. After reinforcing the CFRP sheets and incorporating Near-Surface-Mounted (NSM)-CFRP bars, the reinforcement system, along with the new concrete jacket, effectively transferred the integrity of the broken pier area and maintained a constant load-bearing capacity for the bridge pier. However, when the CFRP sheet was added to the aforementioned system, the load capacity of the bridge pier increased by more than 60%. Therefore, it can be concluded that seismic enhancement techniques utilizing CFRP sheets and mounted NSM-CFRP bars are successful in enhancing the strength and resilience of the concrete bridge pier.