Farzad Hatami | AmirKabir University Of Technology (original) (raw)

Papers by Farzad Hatami

Iran National Standards Organization, 2023

This standard is a part of a set of standards with the general title of organization and digitiza... more This standard is a part of a set of standards with the general title of organization and digitization of building information and civil engineering activities, including information modeling. This document is designed to enable an appointing party (such as an asset owner, asset operator or outsourced asset management provider) to establish their requirements for information during the operational phase of an asset. This document is also designed to enable them to provide the appropriate collaborative environment to fulfill commercial goals. Within this environment, multiple appointed parties can produce information in an effective and efficient manner.
If this document is being applied in relation to a particular asset then this should be reflected in the relevant appointments.
This document is applicable to assets of all sizes and all levels of complexity. This includes portfolios of buildings, campuses, infrastructure networks, individual buildings and pieces of infrastructure such as roads, bridges, footpaths, streetlights, water pipes or sewers. The requirements in this document should be applied in a way that is proportionate and appropriate to the scale and complexity of the asset.
Continuity of information management over the lifetime of an asset is important and it is recommended that all feasible steps (including transfer of the asset information model) are taken to ensure this whenever an asset is transferred from one owner to another.

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Amirkabir Journal of Civil Engineering, 2024

Eccentrically braced frames are one type of lateral load bearing systems due to their acceptable ... more Eccentrically braced frames are one type of lateral load bearing systems due to their acceptable ductility and proportional stiffness. However, they have some limitations that need improvement. One limitation is insufficient architectural space creation especially for short spans which leads to using link beams with medium and long lengths that have weaker energy absorption compared to links with short lengths. Another limitation is their costly and time-consuming replacement. To address these limitations, this research proposes removing diagonal elements from eccentrically braced frames and increasing beam depth outside links which provides more proportional stiffness and improved architectural space for designers. Additionally, using replaceable connections between links and main beams reduces repair costs after earthquakes. Numerical modeling was used to investigate this idea along with laboratory studies. The ratio between increased beam depth outside links and frame stiffness was found through numerical modeling samples with gradual increases in beam depth without braces. Finally, a relationship between increased beam depth outside links and increased frame stiffness was proposed to improve energy absorption amount and system ductility.

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Iranian Journal of Science and Technology - Transactions of Civil Engineering, 2023

The beam is well known as one of the most important members of reinforced concrete structures, wh... more The beam is well known as one of the most important members of reinforced concrete structures, which requires employing new materials due to several reasons. Substituting commonly used materials with new materials is a practical method to increase the bearing resistance (BR) of reinforced concrete beams. Fiber-reinforced polymer (FRP) rebar is one of the new materials with less weight and higher resistance than common rebar, which can better resist shear cracks and reduce concrete implementation costs. The present study utilized glass fiber-reinforced polymer (GFRP) for building concrete beams with cross-sectional dimensions of 200 × 300 mm and a length of 2000 mm. For this purpose, the four-point loading test method was utilized. The results of regression models revealed that concrete beams with GFRP rebar and a steel joint had the highest correlation coefficient (0.988) and the lowest error (0.48411), indicating that the proposed model is more accurate than other investigated concrete beams. Moreover, it could be concluded that the applied load has the highest effect on the displacement of beams without rebar and a GFRP joint, where longitudinal rebar could affect the longitudinal strain in addition to the applied load if substituted with GFRP rebar. Additionally, if the beam is replaced by GFRP joints instead of normal joints, the rotational strain can be considered one of the significant variables. Other results indicated that using GFRP rebar instead of steel bar decreased the load-bearing capacity by 55%, increased beam deflection by 28%, reduced energy absorption by 64%, and raised longitudinal and rotational strains by 32% and 20%, respectively. Furthermore, the simultaneous use of GFRP rebar and joint instead of a steel bar and joint results in a 49% decrease in load-bearing capacity, 45% increase in deflection, 59% reduction in energy absorption, 164% increase in longitudinal strain, and 50% increase in rotational strain.

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Smart Materials and Structures, 2023

In this study two types of SMAs (NiTi and Cu-Al-Mn) are used in this paper to reinforce nine diff... more In this study two types of SMAs (NiTi and Cu-Al-Mn) are used in this paper to reinforce nine different concrete bridge piers in which Engineered Cementitious Composite (ECC) is also used for enhancing ductility in the plastic hinge region. Each of the piers is subjected to 56 near-field ground motions and the collapse capacity of the piers is evaluated probabilistically using Incremental Dynamic Analysis (IDA).

DOI 10.1088/1361-665X/acbcb0

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ACI Materials Journal

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Solid State Technology, Apr 1, 2021

publication description Extensive research has long been conducted on the corrosion of steel bars... more publication description Extensive research has long been conducted on the corrosion of steel bars in reinforced concrete structures. Recently, to prevent damage caused by this problem, the use of non-steel bars has been proposed as an alternative material. Barriers such as low modulus of elasticity (rigidity), low ultimate strain (or failure), low ductility, and low resistance to the environmental conditions of the Alkaline, have left their use as a definitive alternative shrouded in mystery. To solve some of these problems, a new generation of bars has been introduced as composite hybrid bars. These bars are made of a combination of different fibers in bars’ cross-section, and according to the calculations, this combination should give these bars a pseudo-ductile behavior. In this research project, 2 composite hybrid bars were made of glass composite fibers and steel bars and the results of tensile tests in these bars showed the pseudo-ductile behavior. Moreover, their elastic modulus and tensile strength were about 96 Gpa and 99Mpa, respectively.

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World Academy of Science, Engineering and Technology, International Journal of Civil and Environmental Engineering, Aug 6, 2015

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Advanced Steel Construction, 2022

In this study, two novel steel connections are introduced by replacements in the conventional end... more In this study, two novel steel connections are introduced by replacements in the conventional end-plate connection with an H-or I-shaped cross-section as a Short Stub Column (SSC). In the first connection, the SSC flange is bolted to the column flange, and the beam is welded to the stub flange. In the second connection, after welding the SSC flange to the column flange and welding the beam to an end-plate, the end-plate is bolted to the SSC flange. The flange and web of the stub are reinforced using horizontal stiffeners to transfer the beam moment. Stiffeners could be employed with various thicknesses and configurations such that the strength and ductility of the joint could be adjusted. In this study, the Finite Element Model (FEM) model of a conventional welded and bolted end-plate connection, subjected to cyclic loading, is primarily calibrated using experimental data from previous studies. After confirming the model's performance, the behavior of the two proposed connections, in comparison with it, has been studied. The hysteresis diagrams have been obtained for each case, followed by extracting the effective parameters and comparing them. The results show that the two Proposed Connections reduce the stress in the panel zone and increase the ductility compared to the previously confirmed end-plates. All the samples in this study satisfy the fundamental requirements for rigid beam-to-column connections, according to AISC.

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International Journal of Sustainable Construction Engineering and Technology, 2015

Nowadays, because of the steel desired tensile, compressive strength, and light weight especially... more Nowadays, because of the steel desired tensile, compressive strength, and light weight especially in the large spans, it has been widely popular in the bridge construction. On the other hand, there are some disadvantages including corrosion, buckling and weaknesses in the higher temperatures, and unsuitable weld which would be resolved using Fibres Reinforced Polymer (FRP) profiles. The FRP is a remarkable class of composite polymers that can improve structural elements behaviours like as resistance against corrosion, fire, electricity, and magnetic fields. In this paper, composite GFRP & UHF beams along with the behaviour of I-shaped beam were studied and discussed under the point loads using numerical models, results were compared and verified with the experimental tests whereas two different beams were modelled and verified under static progressive loading performed with ABAQUS as an FEM base software. Finally, Moddares-Haqqani that is a steel girder bridge has been modeled by SA...

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Sharif Journal of Civil Engineering (SJCE), 2022

This paper puts forward a new dual system to dissipate energy and presents its numerical studies.... more This paper puts forward a new dual system to dissipate energy and presents its numerical studies. Though moment-resisting frames have a good ductility performance, they suffer from low stiffness as, a matter of fact, engineers try to increase the stiffness by reducing the span length of these frames. On the other hand, in order to ensure the formation of plastic hinges at the two ends of the beam, the codes suggest a minimum limit for the clear span-to-depth ratio of such frames.
To solve this problem, this paper proposes a new dual system. The proposed dual system includes a moment resting frame and a frame with a replaceable beam with a smaller cross-section than that of the main beam which is placed at the mid-span of the beam and designed to act as a shear fuse. This shifts the location of the plastic hinge from the ends of the beam to its middle since the shear fuse yields in shear prior to the flexural yielding of the main beam. This dual system eliminates the need to comply with the rigorous limitation on the beam clear span to the depth ratio that is proposed by seismic design codes. Moreover, this system enjoys an increase in the amount of stiffness. It is worth mentioning that this dual system increases the resilience of the building as the shear fuse is readily replaceable after an earthquake.
With the verification of an experimental model, finite element numerical models are produced. The ABAQUS numerical models show that system that includes both moments resisting frame and shear link frame functions much better than the moment-resisting frames system. As a result, by enjoying this dual system, as well as using the ductility of moment-resisting frames, the stiffness of the building does not decrease noticeably.
Keywords: Moment resisting frame, Dual System, Shear Link, Low span to depth ratio.

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https://civil-ferdowsi.um.ac.ir/article\_42024.html, 2022

In this research, an investigation and comparison between steel rebars and stirrups with GFRP reb... more In this research, an investigation and comparison between steel rebars and stirrups with GFRP rebars and stirrups wa made by making several concrete beams in which the main variables were rebars and stirrups. Therefore, to achieve this goal, three concrete beams with cross-sectional dimensions of 200 by 300 mm with a length of 2000 mm were constructed. The main variables in these beams are rebars and stirrups so that the first beam be reinforced by steel rebars and stirrups, the second beam by GFRP rebars and steel stirrups, and the third beam by GFRP rebars and stirrups. The resistance of concrete in all three beams was assumed to be constant. These beams were subjected to a four-point loading in the laboratory, and the four beams were compared based on the P-delta curve and the obtained results of the strain gauge data that were installed on the beams.

The article could be freely accessed through the doi link below:
10.22067/JFCEI.2022.75533.1125

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ACI MATERIALS JOURNAL, 2022

I am excited to announce that our new research paper, entitled "Seismic Fragility Assessment of B... more I am excited to announce that our new research paper, entitled "Seismic Fragility Assessment of Bridge Pier Reinforced by High-Performance Fiber-Reinforced Concrete and Shape Memory Alloys” has been recently published in the ACI MATERIALS JOURNAL.

In this study, nine samples of bridge piers are reinforced by two types of SMA (NiTi and Cu-Al-Mn) in plastic hinge regions where highperformance fiber-reinforced concrete (HPFRC) is additionally used to enhance the ductility of piers. Shape memory alloys (SMAs), with their unique ability to undergo large deformations and recover to their initial shapes through the removal of stress without significant residual strain, have become attractive materials in bridge engineering. To investigate the effects of SMAs and HPFRC on seismic performance of concrete bridge piers, 28 near-field ground-motion record pairs are selected. Then, the models are analyzed using the incremental dynamic analysis (IDA) method and fragility curves are derived. The results show that using SMAs leads to the reduction of residual drift. Also, using HPFRC increases the capacity of the models. Furthermore, the model with HPFRC and NiTi shows the best performance in terms of capacity and residual drift reduction.
It was a great pleasure to work with Professor Mesbah Saybani and Eng. Amirmozafar Benshams.

The article could be freely accessed through the doi link below:
doi: 10.14359/51734685

Bookmarks Related papers MentionsView impact

Bookmarks Related papers MentionsView impact

Cleaner Materials, 2022

In this experimental study, the impact of using waste materials such as ground granulated blast f... more In this experimental study, the impact of using waste materials such as ground granulated blast furnace slag (GGBFS), waste rubber powder (WRP), and recycled concrete aggregate (RCA) were evaluated on the compressive, tensile and, flexural strengths and durability test of rapid chloride migration test (RCMT) of concrete. It was observed that the mechanical properties of concrete decreased by raising the proportions of recycled materials in all replacement ratios. Because of the adverse effects of the WRP and RCA on the cement matrix and the interfacial transition zone, the reduction of the mechanical properties is higher for the concrete specimens with both recycled materials. In the case of durability, the migration rate of chloride ions in concrete is reduced by increasing the WRP rates due to the blockage of micro-pores connections. However, adding the RCA has a negative effect on the durability performance of concrete. Regarding the simultaneous effect of slag, rubber powder, and recycled aggregate on the migration of chloride ions, it can be derived that durability of samples containing 20% slag, 2.5% rubber powder, and 25% recycled aggregate at the age of 7 days on average is 14.8% higher compared to the reference sample. As the age of the samples increases to 28 days, the migration of chloride ions in the samples reduced 9.5% compared to 7 days.

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ASAS (Journal of Iranian Society of Civil Engineering), 2022

This paper studies the seismic behavior of rectangular and cylindrical tanks under near-fault and... more This paper studies the seismic behavior of rectangular and cylindrical tanks under near-fault and far-fault ground motions. To compare the seismic response of these tanks, the plan dimensions of them are chosen in such a way that the volume of liquid stored in the tanks remains virtually constant at the same liquid heights. Two near-fault and three far-fault ground motions with different frequency content are applied to the tanks. The sloshing, wall pressure, and hydrodynamic pressure responses of these tanks were discussed. The critical locations of the mentioned responses are also studied. ALE-based finite element method is employed using ABAQUS software to model the liquid-tank system. The accuracy of this modeling technique is evaluated using some experimental results available in the literature. The results indicate that the tank’s shape and earthquake characteristics significantly affect the seismic response of liquid storage tanks.

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Advanced Steel Construction, 2022

In this study, two novel steel connections are introduced by replacements in the conventional end... more In this study, two novel steel connections are introduced by replacements in the conventional end-plate connection with an H-or I-shaped cross-section as a Short Stub Column (SSC). In the first connection, the SSC flange is bolted to the column flange, and the beam is welded to the stub flange. In the second connection, after welding the SSC flange to the column flange and welding the beam to an end-plate, the end-plate is bolted to the SSC flange. The flange and web of the stub are reinforced using horizontal stiffeners to transfer the beam moment. Stiffeners could be employed with various thicknesses and configurations such that the strength and ductility of the joint could be adjusted. In this study, the Finite Element Model (FEM) model of a conventional welded and bolted end-plate connection, subjected to cyclic loading, is primarily calibrated using experimental data from previous studies. After confirming the model's performance, the behavior of the two proposed connections, in comparison with it, has been studied. The hysteresis diagrams have been obtained for each case, followed by extracting the effective parameters and comparing them. The results show that the two Proposed Connections reduce the stress in the panel zone and increase the ductility compared to the previously confirmed end-plates. All the samples in this study satisfy the fundamental requirements for rigid beam-to-column connections, according to AISC.

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Journal of Renewable Materials

In this experimental study, the impact of Portland cement replacement by ground granulated blast ... more In this experimental study, the impact of Portland cement replacement by ground granulated blast furnace slag (GGBFS) and micronized rubber powder (MRP) on the compressive, flexural, tensile strengths, and rapid chloride migration test (RCMT) of concrete were assessed. In this study, samples with different binder content and water to binder ratios, including the MRP with the substitution levels of 0%, 2.5% and 5%, and the GGBFS with the substitution ratios of 0%, 20% and 40% by weight of Portland cement were made. According to the results, in the samples containing slag and rubber powder in the early ages, on average, a 12.2% decrease in the mechanical characteristics of concrete was observed, nonetheless with raising the age of the samples, the impact of slag on reducing the porosity of concrete lowered the negative impact of rubber powder. Regarding durability characteristics, the RCMT results of the samples were enhanced by using rubber powder because of its insulation impact. Moreover, adding slag into the MRP-included mixtures results in a 23% reduction in the migration rate of the chloride ion averagely. At last, four mathematical statements were derived for the mechanical and durability of concrete containing the MRP and GGBFS utilizing the genetic programming method. KEYWORDS Micronized rubber powder; ground granulated blast furnace slag; waste materials; mechanical properties; durability Ground granulated blast furnace slag is one of the by-products of the steel plant that does not react if water is added to it. Unlike pozzolans, which react with and consume calcium hydroxide from cement This work is licensed under a Creative Commons Attribution 4.0 International License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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Iran National Standards Organization, 2023

This standard is a part of a set of standards with the general title of organization and digitiza... more This standard is a part of a set of standards with the general title of organization and digitization of building information and civil engineering activities, including information modeling. This document is designed to enable an appointing party (such as an asset owner, asset operator or outsourced asset management provider) to establish their requirements for information during the operational phase of an asset. This document is also designed to enable them to provide the appropriate collaborative environment to fulfill commercial goals. Within this environment, multiple appointed parties can produce information in an effective and efficient manner.
If this document is being applied in relation to a particular asset then this should be reflected in the relevant appointments.
This document is applicable to assets of all sizes and all levels of complexity. This includes portfolios of buildings, campuses, infrastructure networks, individual buildings and pieces of infrastructure such as roads, bridges, footpaths, streetlights, water pipes or sewers. The requirements in this document should be applied in a way that is proportionate and appropriate to the scale and complexity of the asset.
Continuity of information management over the lifetime of an asset is important and it is recommended that all feasible steps (including transfer of the asset information model) are taken to ensure this whenever an asset is transferred from one owner to another.

Bookmarks Related papers MentionsView impact

Amirkabir Journal of Civil Engineering, 2024

Eccentrically braced frames are one type of lateral load bearing systems due to their acceptable ... more Eccentrically braced frames are one type of lateral load bearing systems due to their acceptable ductility and proportional stiffness. However, they have some limitations that need improvement. One limitation is insufficient architectural space creation especially for short spans which leads to using link beams with medium and long lengths that have weaker energy absorption compared to links with short lengths. Another limitation is their costly and time-consuming replacement. To address these limitations, this research proposes removing diagonal elements from eccentrically braced frames and increasing beam depth outside links which provides more proportional stiffness and improved architectural space for designers. Additionally, using replaceable connections between links and main beams reduces repair costs after earthquakes. Numerical modeling was used to investigate this idea along with laboratory studies. The ratio between increased beam depth outside links and frame stiffness was found through numerical modeling samples with gradual increases in beam depth without braces. Finally, a relationship between increased beam depth outside links and increased frame stiffness was proposed to improve energy absorption amount and system ductility.

Bookmarks Related papers MentionsView impact

Iranian Journal of Science and Technology - Transactions of Civil Engineering, 2023

The beam is well known as one of the most important members of reinforced concrete structures, wh... more The beam is well known as one of the most important members of reinforced concrete structures, which requires employing new materials due to several reasons. Substituting commonly used materials with new materials is a practical method to increase the bearing resistance (BR) of reinforced concrete beams. Fiber-reinforced polymer (FRP) rebar is one of the new materials with less weight and higher resistance than common rebar, which can better resist shear cracks and reduce concrete implementation costs. The present study utilized glass fiber-reinforced polymer (GFRP) for building concrete beams with cross-sectional dimensions of 200 × 300 mm and a length of 2000 mm. For this purpose, the four-point loading test method was utilized. The results of regression models revealed that concrete beams with GFRP rebar and a steel joint had the highest correlation coefficient (0.988) and the lowest error (0.48411), indicating that the proposed model is more accurate than other investigated concrete beams. Moreover, it could be concluded that the applied load has the highest effect on the displacement of beams without rebar and a GFRP joint, where longitudinal rebar could affect the longitudinal strain in addition to the applied load if substituted with GFRP rebar. Additionally, if the beam is replaced by GFRP joints instead of normal joints, the rotational strain can be considered one of the significant variables. Other results indicated that using GFRP rebar instead of steel bar decreased the load-bearing capacity by 55%, increased beam deflection by 28%, reduced energy absorption by 64%, and raised longitudinal and rotational strains by 32% and 20%, respectively. Furthermore, the simultaneous use of GFRP rebar and joint instead of a steel bar and joint results in a 49% decrease in load-bearing capacity, 45% increase in deflection, 59% reduction in energy absorption, 164% increase in longitudinal strain, and 50% increase in rotational strain.

Bookmarks Related papers MentionsView impact

Smart Materials and Structures, 2023

In this study two types of SMAs (NiTi and Cu-Al-Mn) are used in this paper to reinforce nine diff... more In this study two types of SMAs (NiTi and Cu-Al-Mn) are used in this paper to reinforce nine different concrete bridge piers in which Engineered Cementitious Composite (ECC) is also used for enhancing ductility in the plastic hinge region. Each of the piers is subjected to 56 near-field ground motions and the collapse capacity of the piers is evaluated probabilistically using Incremental Dynamic Analysis (IDA).

DOI 10.1088/1361-665X/acbcb0

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ACI Materials Journal

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Solid State Technology, Apr 1, 2021

publication description Extensive research has long been conducted on the corrosion of steel bars... more publication description Extensive research has long been conducted on the corrosion of steel bars in reinforced concrete structures. Recently, to prevent damage caused by this problem, the use of non-steel bars has been proposed as an alternative material. Barriers such as low modulus of elasticity (rigidity), low ultimate strain (or failure), low ductility, and low resistance to the environmental conditions of the Alkaline, have left their use as a definitive alternative shrouded in mystery. To solve some of these problems, a new generation of bars has been introduced as composite hybrid bars. These bars are made of a combination of different fibers in bars’ cross-section, and according to the calculations, this combination should give these bars a pseudo-ductile behavior. In this research project, 2 composite hybrid bars were made of glass composite fibers and steel bars and the results of tensile tests in these bars showed the pseudo-ductile behavior. Moreover, their elastic modulus and tensile strength were about 96 Gpa and 99Mpa, respectively.

Bookmarks Related papers MentionsView impact

World Academy of Science, Engineering and Technology, International Journal of Civil and Environmental Engineering, Aug 6, 2015

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Advanced Steel Construction, 2022

In this study, two novel steel connections are introduced by replacements in the conventional end... more In this study, two novel steel connections are introduced by replacements in the conventional end-plate connection with an H-or I-shaped cross-section as a Short Stub Column (SSC). In the first connection, the SSC flange is bolted to the column flange, and the beam is welded to the stub flange. In the second connection, after welding the SSC flange to the column flange and welding the beam to an end-plate, the end-plate is bolted to the SSC flange. The flange and web of the stub are reinforced using horizontal stiffeners to transfer the beam moment. Stiffeners could be employed with various thicknesses and configurations such that the strength and ductility of the joint could be adjusted. In this study, the Finite Element Model (FEM) model of a conventional welded and bolted end-plate connection, subjected to cyclic loading, is primarily calibrated using experimental data from previous studies. After confirming the model's performance, the behavior of the two proposed connections, in comparison with it, has been studied. The hysteresis diagrams have been obtained for each case, followed by extracting the effective parameters and comparing them. The results show that the two Proposed Connections reduce the stress in the panel zone and increase the ductility compared to the previously confirmed end-plates. All the samples in this study satisfy the fundamental requirements for rigid beam-to-column connections, according to AISC.

Bookmarks Related papers MentionsView impact

International Journal of Sustainable Construction Engineering and Technology, 2015

Nowadays, because of the steel desired tensile, compressive strength, and light weight especially... more Nowadays, because of the steel desired tensile, compressive strength, and light weight especially in the large spans, it has been widely popular in the bridge construction. On the other hand, there are some disadvantages including corrosion, buckling and weaknesses in the higher temperatures, and unsuitable weld which would be resolved using Fibres Reinforced Polymer (FRP) profiles. The FRP is a remarkable class of composite polymers that can improve structural elements behaviours like as resistance against corrosion, fire, electricity, and magnetic fields. In this paper, composite GFRP & UHF beams along with the behaviour of I-shaped beam were studied and discussed under the point loads using numerical models, results were compared and verified with the experimental tests whereas two different beams were modelled and verified under static progressive loading performed with ABAQUS as an FEM base software. Finally, Moddares-Haqqani that is a steel girder bridge has been modeled by SA...

Bookmarks Related papers MentionsView impact

Bookmarks Related papers MentionsView impact

Bookmarks Related papers MentionsView impact

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Sharif Journal of Civil Engineering (SJCE), 2022

This paper puts forward a new dual system to dissipate energy and presents its numerical studies.... more This paper puts forward a new dual system to dissipate energy and presents its numerical studies. Though moment-resisting frames have a good ductility performance, they suffer from low stiffness as, a matter of fact, engineers try to increase the stiffness by reducing the span length of these frames. On the other hand, in order to ensure the formation of plastic hinges at the two ends of the beam, the codes suggest a minimum limit for the clear span-to-depth ratio of such frames.
To solve this problem, this paper proposes a new dual system. The proposed dual system includes a moment resting frame and a frame with a replaceable beam with a smaller cross-section than that of the main beam which is placed at the mid-span of the beam and designed to act as a shear fuse. This shifts the location of the plastic hinge from the ends of the beam to its middle since the shear fuse yields in shear prior to the flexural yielding of the main beam. This dual system eliminates the need to comply with the rigorous limitation on the beam clear span to the depth ratio that is proposed by seismic design codes. Moreover, this system enjoys an increase in the amount of stiffness. It is worth mentioning that this dual system increases the resilience of the building as the shear fuse is readily replaceable after an earthquake.
With the verification of an experimental model, finite element numerical models are produced. The ABAQUS numerical models show that system that includes both moments resisting frame and shear link frame functions much better than the moment-resisting frames system. As a result, by enjoying this dual system, as well as using the ductility of moment-resisting frames, the stiffness of the building does not decrease noticeably.
Keywords: Moment resisting frame, Dual System, Shear Link, Low span to depth ratio.

Bookmarks Related papers MentionsView impact

https://civil-ferdowsi.um.ac.ir/article\_42024.html, 2022

In this research, an investigation and comparison between steel rebars and stirrups with GFRP reb... more In this research, an investigation and comparison between steel rebars and stirrups with GFRP rebars and stirrups wa made by making several concrete beams in which the main variables were rebars and stirrups. Therefore, to achieve this goal, three concrete beams with cross-sectional dimensions of 200 by 300 mm with a length of 2000 mm were constructed. The main variables in these beams are rebars and stirrups so that the first beam be reinforced by steel rebars and stirrups, the second beam by GFRP rebars and steel stirrups, and the third beam by GFRP rebars and stirrups. The resistance of concrete in all three beams was assumed to be constant. These beams were subjected to a four-point loading in the laboratory, and the four beams were compared based on the P-delta curve and the obtained results of the strain gauge data that were installed on the beams.

The article could be freely accessed through the doi link below:
10.22067/JFCEI.2022.75533.1125

Bookmarks Related papers MentionsView impact

ACI MATERIALS JOURNAL, 2022

I am excited to announce that our new research paper, entitled "Seismic Fragility Assessment of B... more I am excited to announce that our new research paper, entitled "Seismic Fragility Assessment of Bridge Pier Reinforced by High-Performance Fiber-Reinforced Concrete and Shape Memory Alloys” has been recently published in the ACI MATERIALS JOURNAL.

In this study, nine samples of bridge piers are reinforced by two types of SMA (NiTi and Cu-Al-Mn) in plastic hinge regions where highperformance fiber-reinforced concrete (HPFRC) is additionally used to enhance the ductility of piers. Shape memory alloys (SMAs), with their unique ability to undergo large deformations and recover to their initial shapes through the removal of stress without significant residual strain, have become attractive materials in bridge engineering. To investigate the effects of SMAs and HPFRC on seismic performance of concrete bridge piers, 28 near-field ground-motion record pairs are selected. Then, the models are analyzed using the incremental dynamic analysis (IDA) method and fragility curves are derived. The results show that using SMAs leads to the reduction of residual drift. Also, using HPFRC increases the capacity of the models. Furthermore, the model with HPFRC and NiTi shows the best performance in terms of capacity and residual drift reduction.
It was a great pleasure to work with Professor Mesbah Saybani and Eng. Amirmozafar Benshams.

The article could be freely accessed through the doi link below:
doi: 10.14359/51734685

Bookmarks Related papers MentionsView impact

Bookmarks Related papers MentionsView impact

Cleaner Materials, 2022

In this experimental study, the impact of using waste materials such as ground granulated blast f... more In this experimental study, the impact of using waste materials such as ground granulated blast furnace slag (GGBFS), waste rubber powder (WRP), and recycled concrete aggregate (RCA) were evaluated on the compressive, tensile and, flexural strengths and durability test of rapid chloride migration test (RCMT) of concrete. It was observed that the mechanical properties of concrete decreased by raising the proportions of recycled materials in all replacement ratios. Because of the adverse effects of the WRP and RCA on the cement matrix and the interfacial transition zone, the reduction of the mechanical properties is higher for the concrete specimens with both recycled materials. In the case of durability, the migration rate of chloride ions in concrete is reduced by increasing the WRP rates due to the blockage of micro-pores connections. However, adding the RCA has a negative effect on the durability performance of concrete. Regarding the simultaneous effect of slag, rubber powder, and recycled aggregate on the migration of chloride ions, it can be derived that durability of samples containing 20% slag, 2.5% rubber powder, and 25% recycled aggregate at the age of 7 days on average is 14.8% higher compared to the reference sample. As the age of the samples increases to 28 days, the migration of chloride ions in the samples reduced 9.5% compared to 7 days.

Bookmarks Related papers MentionsView impact

ASAS (Journal of Iranian Society of Civil Engineering), 2022

This paper studies the seismic behavior of rectangular and cylindrical tanks under near-fault and... more This paper studies the seismic behavior of rectangular and cylindrical tanks under near-fault and far-fault ground motions. To compare the seismic response of these tanks, the plan dimensions of them are chosen in such a way that the volume of liquid stored in the tanks remains virtually constant at the same liquid heights. Two near-fault and three far-fault ground motions with different frequency content are applied to the tanks. The sloshing, wall pressure, and hydrodynamic pressure responses of these tanks were discussed. The critical locations of the mentioned responses are also studied. ALE-based finite element method is employed using ABAQUS software to model the liquid-tank system. The accuracy of this modeling technique is evaluated using some experimental results available in the literature. The results indicate that the tank’s shape and earthquake characteristics significantly affect the seismic response of liquid storage tanks.

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Advanced Steel Construction, 2022

In this study, two novel steel connections are introduced by replacements in the conventional end... more In this study, two novel steel connections are introduced by replacements in the conventional end-plate connection with an H-or I-shaped cross-section as a Short Stub Column (SSC). In the first connection, the SSC flange is bolted to the column flange, and the beam is welded to the stub flange. In the second connection, after welding the SSC flange to the column flange and welding the beam to an end-plate, the end-plate is bolted to the SSC flange. The flange and web of the stub are reinforced using horizontal stiffeners to transfer the beam moment. Stiffeners could be employed with various thicknesses and configurations such that the strength and ductility of the joint could be adjusted. In this study, the Finite Element Model (FEM) model of a conventional welded and bolted end-plate connection, subjected to cyclic loading, is primarily calibrated using experimental data from previous studies. After confirming the model's performance, the behavior of the two proposed connections, in comparison with it, has been studied. The hysteresis diagrams have been obtained for each case, followed by extracting the effective parameters and comparing them. The results show that the two Proposed Connections reduce the stress in the panel zone and increase the ductility compared to the previously confirmed end-plates. All the samples in this study satisfy the fundamental requirements for rigid beam-to-column connections, according to AISC.

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Journal of Renewable Materials

In this experimental study, the impact of Portland cement replacement by ground granulated blast ... more In this experimental study, the impact of Portland cement replacement by ground granulated blast furnace slag (GGBFS) and micronized rubber powder (MRP) on the compressive, flexural, tensile strengths, and rapid chloride migration test (RCMT) of concrete were assessed. In this study, samples with different binder content and water to binder ratios, including the MRP with the substitution levels of 0%, 2.5% and 5%, and the GGBFS with the substitution ratios of 0%, 20% and 40% by weight of Portland cement were made. According to the results, in the samples containing slag and rubber powder in the early ages, on average, a 12.2% decrease in the mechanical characteristics of concrete was observed, nonetheless with raising the age of the samples, the impact of slag on reducing the porosity of concrete lowered the negative impact of rubber powder. Regarding durability characteristics, the RCMT results of the samples were enhanced by using rubber powder because of its insulation impact. Moreover, adding slag into the MRP-included mixtures results in a 23% reduction in the migration rate of the chloride ion averagely. At last, four mathematical statements were derived for the mechanical and durability of concrete containing the MRP and GGBFS utilizing the genetic programming method. KEYWORDS Micronized rubber powder; ground granulated blast furnace slag; waste materials; mechanical properties; durability Ground granulated blast furnace slag is one of the by-products of the steel plant that does not react if water is added to it. Unlike pozzolans, which react with and consume calcium hydroxide from cement This work is licensed under a Creative Commons Attribution 4.0 International License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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Original method for steel production, which is implemented for close up to 90 percent of steel pr... more Original method for steel production, which is implemented for close up to 90 percent of steel production, is the transformation of iron ore into iron in the blast furnace after the formation of steel in basic oxygen furnace. Today, the high volume of steel slags has become a critical problem in waste management. However, blast furnace slag due to its pozzolanic properties can be used for partial replacement of Portland cement. The purpose of this article is to process blast furnace slag and turn it into an effective material in the cement industry. The results showed that the physical processing of slag by grinding it into 75 microns and increasing alkalinity state by adding lime can lead to an increase of 117 percent in 11-day compressive strength of slag cement against unprocessed one. This conclusion is achieved through experiments conducted on 18 different samples.

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Amirkabir University Publication

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Iran National Standards Organizations, 2023

Organization and digitization of buildings and civil engineering works including standard informa... more Organization and digitization of buildings and civil engineering works including standard information modeling- Construction information management using construction information modeling - Part 5: Security approach to information management, which is drafted in the relevant commissions based on the acceptance of international or regional standards As the national standard of Iran, according to the method mentioned in item A, paragraph 7, the national standard of Iran No. 5 was prepared has been compiled.

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Iran National Standards Organization, 2023

Organization and digitization of buildings and civil engineering works including standard informa... more Organization and digitization of buildings and civil engineering works including standard information modeling- Management of construction information using construction information modeling - Part 2: The stage of delivery of construction assets, which is drafted in the relevant commissions based on the acceptance of international or regional standards.
As the national standard of Iran, according to the method mentioned in item A, paragraph 7, the national standard of Iran No. 5 was prepared has been compiled.

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Iran National Standards Organization, 2023

This standard is a part of a set of standards with the general title of organization and digitiza... more This standard is a part of a set of standards with the general title of organization and digitization of building information and civil engineering activities, including information modeling. This document is designed to enable an appointing party (such as an asset owner, asset operator or outsourced asset management provider) to establish their requirements for information during the operational phase of an asset. This document is also designed to enable them to provide the appropriate collaborative environment to fulfill commercial goals. Within this environment, multiple appointed parties can produce information in an effective and efficient manner.
If this document is being applied in relation to a particular asset then this should be reflected in the relevant appointments.
This document is applicable to assets of all sizes and all levels of complexity. This includes portfolios of buildings, campuses, infrastructure networks, individual buildings and pieces of infrastructure such as roads, bridges, footpaths, streetlights, water pipes or sewers. The requirements in this document should be applied in a way that is proportionate and appropriate to the scale and complexity of the asset.
Continuity of information management over the lifetime of an asset is important and it is recommended that all feasible steps (including transfer of the asset information model) are taken to ensure this whenever an asset is transferred from one owner to another.

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ACECR Publication, Amirkabir University of Technology Branch, 2023

It is an honour to present my book on "Application of FRP composite materials in structural engin... more It is an honour to present my book on "Application of FRP composite materials in structural engineering" It combines theoretical formulation and experimental models about the Fiber Reinforcement Polymer Application in structural engineering.

This Book has 5 chapters which are:
· Introduction
· Introduction of FRP composite materials, their characteristics and applications
· Numerical studies and software modeling
· Investigating the use of FRP fibers in buildings
· Investigating the use of FRP fibers in bridges
Many thanks to my distinguished co-author Professor Mesbah Sayehbani and cooperation of Eng. Amirmozafar Benshams.

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Iran National Standards Organization, 2023

This document is designed to enable an appointing party (such as an asset owner, asset operator o... more This document is designed to enable an appointing party (such as an asset owner, asset operator or outsourced asset management provider) to establish their requirements for information during the operational phase of an asset. This document is also designed to enable them to provide the appropriate collaborative environment to fulfil commercial goals. Within this environment, multiple appointed parties can produce information in an effective and efficient manner.
This document is primarily intended for use by the following:
— those involved in the management of an asset and facility (see 0.2);
— those involved in the specification of appointments and the facilitation of collaborative working during the entire life cycle of an asset;
— those involved in delivering asset management and facility management during the operational phase of an asset (see 0.2); and
— those involved in specifying the information required for operational purposes that needs to be captured during the delivery phase of an asset.
If this document is being applied in relation to a particular asset then this should be reflected in the relevant appointments.
This document is applicable to assets of all sizes and all levels of complexity. This includes portfolios of buildings, campuses, infrastructure networks, individual buildings and pieces of infrastructure such as roads, bridges, footpaths, streetlights, water pipes or sewers. The requirements in this document should be applied in a way that is proportionate and appropriate to the scale and complexity of the asset.
Continuity of information management over the lifetime of an asset is important and it is recommended that all feasible steps (including transfer of the asset information model) are taken to ensure this whenever an asset is transferred from one owner to another.

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Research Center of Technical and Engineering Science of the Passive Defense Organization of Iran, 2021

Passive Defense Requirements and Considerations in High-Rise Buildings

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Hormozgan University, 2019

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Hormozgan University, 2019

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ISBN: 978-600-168-264-3

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ISBN: 978-600-168-265-0 This Book was written in Persian Language.

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Steel and Composite Shear Wall; Principles and Application of New Ideas, Principles and Philosoph... more Steel and Composite Shear Wall; Principles and Application of New Ideas, Principles and Philosophy of Design

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Amirkabir University of Technology and Iranian National Building Cod center, Jan 21, 2014

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Amirkabir University of Technology and Iranian National Building Cod center, Nov 16, 2013

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5th International Conference on Bridges (5IBC2019), 2019

Measurement uncertainties were regarded in this work through the introduction of Gaussian white n... more Measurement uncertainties were regarded in this work through the introduction of Gaussian white noise and axle load error into the numerically simulated accelerations, before using them to train the networks. The outcome revealed to be noise sensitive, as expected, but the method seems to be robust and to perform well within typical levels of noise. It is a general conclusion that damage is more effectively detected in the measured signal is less disturbed by the variability of operational and environmental conditions. The operating service loads generally provide the dynamic excitation in ambient vibration testing on the structure. The dynamic excitation must be implicit in being stationary and uncorrelated white noise. Since white noise is a broadband input, a structure's modes of vibration that lie within its sufficient bandwidth can be identified from the output measurements. The white noise excitation is also assumed to be spatially well-distributed over the entire structure, effectively making ambient vibration testing a multiple-input, multiple-output test. In this study, two frames as undamaged and a damaged beam of steel bridge were modeled to evaluate damage detection methods by white noise excitation. In the damaged frame of a steel bridge, one of the beams of steel deck was weakened by a decrease in the modulus of elasticity. These frames were analyzed under the comparable record of the Tabas earthquake and the displacement responses and acceleration of the classes were extracted. The results of the signal analysis and processing showed that the best indicator for evaluating the difference between the dynamic properties of the two frames and the damage detection is the ANN, since any damage, along with significant energy absorption at a specified frequency, can be varied. Also, the natural frequency of both structural obtained by with noise excitation with the ANN algorithm.

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5th International Conference on Bridges (5IBC2019), 2019

The concrete as a brittle material in the construction industry plays an important role in bridge... more The concrete as a brittle material in the construction industry plays an important role in bridge construction and includes one of the important mechanical concepts called "size effect". Besides the improvement in the flexural strength of concrete, the use of fibers has an impressive effect on the size effect. Due to unknown properties of recycled concrete and ignorance of its benefits many aggregates, national reserves are disappearing. The present paper investigates the effect of size effect on the flexural strength of recycled steel fiber concretes. The recycled concretes were made with 30% recycled coarse aggregate and steel fiber volume fraction of 1.5%. After the casting and curing of prisms specimens, the flexural strength test was done. The maximum flexural strength and flexural post-peak behavior of prisms were recorded using LVDT. Compression of all specimens showed that the increment of concrete specimen's size of steel fiber recycled concrete, lead to flexural strength reduction. Furthermore, the influence of size effect on the reduction of flexural strength of recycled concrete is greater than that of recycled concrete steel fiber.

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5th International Conference on Bridges (5IBC2019), 2019

Because of the importance of road communication, bridges are one of the most important arterial s... more Because of the importance of road communication, bridges are one of the most important arterial structures under development in any country that has many research backgrounds. Checking the condition of bridges before the operation and during operation is important to ensure the proper performance of the bridge according to the design in different periods. Besides, transportation development in many cases, requires the use of an existing route for heavy loads as well as higher speeds. Therefore, it is necessary to study the behavior of the bridge during its lifetime and to consider the necessary arrangements for its maintenance and repair. Detecting breakdowns in early stages in structural systems during their service life has attracted the attention of many researchers in recent decades and has been the subject of many research articles in the fields of civil, mechanical, and aerospace engineering. Therefore, the present article presents a methodology for performing bridge health monitoring in order to reach the location and severity of the damage, determining the service life-prediction of the bridge. For this purpose, the accessibility cable bridge of Tehran Milad Tower on Sheikh Fazlollah Nouri highway will be investigated, and numerical simulations will be performed, the types of sensors required as well as the sensor layout architecture and the service life-prediction of the bridge will be evaluated.

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In order to reduce the structural responses under dynamic loading, numerous methods have been pro... more In order to reduce the structural responses under dynamic loading, numerous methods have been proposed. Tuned Mass dampers (TMD) are considered as the most useful tools in the field of vibration control of flexible structures. TMD is a device consisting of mechanical components such as mass, spring and a dashpot implemented on the primary structure to reduce the dynamic responses of the structure. The way of choosing these parameters is one of the main challenges in using TMD. In the present research, the optimum design of tuned mass dampers installed in MDOF structures is studied. Two objective functions are considered and the improved harmony search algorithm are used for optimization of TMD parameters, namely location, mass, stiffness and damping. The numerical simulation was conducted on two 10-story shear structures. Based on the numerical results, the reduction of transfer functions of controlled structures is efficient when the excitation frequency is close to the critical frequency of the uncontrolled structure for both objective functions. Responses of structures under different earthquakes revealed that TMD dampers obtained from both objective functions are effective in reducing the kinetic energy, strain energy and the energy dissipated by the structure. However, the maximum displacement of TMD and force exerted by TMD on structure for in all investigated earthquakes are considerably less for our methods as compared with corrected results of Bekdas and Nigdeli [14]. Finally, it is shown that TMD structures do not necessarily have classical damping despite the classical damping in uncontrolled structure. Therefore, it is recommended that modal analysis method should not be used to calculate the responses of such systems. Therefore, the results of Bekdas and Nigdeli [14] are rectified because of using modal method.

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Original method for steel production, which is implemented for close up to 90 percent of steel pr... more Original method for steel production, which is implemented for close up to 90 percent of steel production, is the transformation of iron ore into iron in the blast furnace after the formation of steel in basic oxygen furnace. Today, the high volume of steel slags has become a critical problem in waste management. However, blast furnace slag due to its pozzolanic properties can be used for partial replacement of Portland cement. The purpose of this article is to process blast furnace slag and turn it into an effective material in the cement industry. The results showed that the physical processing of slag by grinding it into 75 microns and increasing alkalinity state by adding lime can lead to an increase of 117 percent in 11-day compressive strength of slag cement against unprocessed one. This conclusion is achieved through experiments conducted on 18 different samples.

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