List of Articles ashkan khodabandehlou

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  1 - The effect of far and near field earthquakes on the collapse capacity of performance base optimization RC moment frames
  ashkan khodabandehlou siamak saboonchi
  10.30495/civil.2023.1972417.1297
  Performance-based design is a new approach to the topics of seismic design of structures, which is based on changing the location of the structure, unlike the traditional methods of force-based design. The use of this approach in the process of structures design leads t More

  Performance-based design is a new approach to the topics of seismic design of structures, which is based on changing the location of the structure, unlike the traditional methods of force-based design. The use of this approach in the process of structures design leads to the achievement of structures with proper performance and an acceptable level of reliability. The main goal of this research is to investigate the impact of near and far field earthquakes on the collapse capacity and fragility of performance base optimization RC moment frames using the center of mass meta-heuristic algorithm. Push over analysis has been used in the optimization process to control the responses of the studied frames at performance levels and incremental dynamic analysis has been used to evaluate the fragility of the obtained optimal frames. According to the obtained results for the collapse margin ratio and the adjusted collapse margin ratio for the 3, 6, and 12-story frames, we can see that the collapse margin ratio and therefore the seismic safety under far field earthquakes 7%, 16% and 8%, higher than from collapse margin ratio and seismic safety under near field earthquakes respectively. In other words, the optimal frames in this study against near-field earthquakes have low seismic safety and more fragility than far field earthquakes. Manuscript profile
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  2 - Evaluation of Nonlinear Seismic Behavior of Reinforced Concrete moment Frames with Special Ductility with and without Viscous Dampers on the Floors Level
  ashkan khodabandehlou siamak barmaki
  10.30495/civil.2023.1974310.1311
  The main goal of this research is to evaluate the nonlinear seismic behavior of special RC moment with and without viscous dampers at the floor level. In this research, 2 high-rise three-dimensional RC building frames of 12 and 16 stories, each frame with 8 models, 4 mo More

  The main goal of this research is to evaluate the nonlinear seismic behavior of special RC moment with and without viscous dampers at the floor level. In this research, 2 high-rise three-dimensional RC building frames of 12 and 16 stories, each frame with 8 models, 4 models with and 4 models without viscous damper at the floor level, located in the area with High seismicity on type 3 soil is considered. In order to seismic analysis of frames with and without viscous dampers, nonlinear static analysis method was used according to the second appendix of Iran earthquake regulations, fourth edition. The initial dimensions of the structural elements of the studied frames and the thickness of the roof slabs have been determined in ETABS-V15 and SAFE2014 software, respectively, and finally, modeling, gravity and lateral loading, and nonlinear static analysis of the studied frames have been performed in the SAP2000-V19 software. The results show that the change in the sections of beams and columns from square to rectangle in frames with and without viscous damper causes an increase in the relative lateral displacement of the floors, as well as an increase in the number of openings along the Y axis (model 1 compared to 3), and an increase in the length of the opening along the Y axis (model 1 Compared to 4), in frames with and without viscous damper, it reduces the absolute lateral displacement of floors. Manuscript profile
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  3 - The Influence of The Interaction of Soil And Structure on Rein forced Concrete Tall Buildings With Flat Slabs And Internal Resistant Core of Tube in Tube System With Consideration of Nonlinear Dynamic Analysis
  Reza Hoseini ashkan khodabandehlou
  20.1001.1.23456310.1398.16.2.1.8
  In this study, 2 reinforced concrete 3D building frames for a 28-storey building are going to be considered and analyzesThese frames are in both X andYdirections with tube in tube structural system and a flat plate roof with rigid internal core in the shape of H, in a r More

  In this study, 2 reinforced concrete 3D building frames for a 28-storey building are going to be considered and analyzesThese frames are in both X andYdirections with tube in tube structural system and a flat plate roof with rigid internal core in the shape of H, in a relatively high risk zone (A=0.3 g) on two kinds of soil, with and without soil-structure interaction.The goal of this study is to determine the maximum drift and displacement of the storeys under gravity loads(dead  live) and lateral load of earthquake. A discrete model based on a buried footing Cone Model in homogeneous half space of volf and meek is used to model the soil under the foundation and also to determine dynamic stiffness coefficient and Soil damping cofficient and a substructure method with the footing rigidity assumption is used to analyze the frames with the soil-structure intraction  effect. A dynamic analysis of the nonlinear timeline history of seven accelerograms is used to analyze earthquake load and geometric modeling of all  frames with internal core has been done in sap2000-V17software.The results show that the maximum drift and displacement of the storeys with soil-structure interaction in X and Ydirection was not different with the one without interaction and that they are equal. By changing the type of soil with and without soil-structure interaction, the maximum drift of storeys in X direction had a descending increment process of 22 percent and in Y direction, had 25 percent is increment. Manuscript profile
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  4 - Investigating the Effect of Using Seismic Separators on Seismic Improvement of Steel frames
  ashkan khodabandehlou hamid saeidian
  20.1001.1.23456310.1397.15.4.1.5
  The idea that a building can be uncoupled from the damaging effects of the ground movement produced by a strong earthquake has appealed to inventors and engineers for more than a century. Seismic isolation is effective in reducing seismic demand for buildings and decrea More

  The idea that a building can be uncoupled from the damaging effects of the ground movement produced by a strong earthquake has appealed to inventors and engineers for more than a century. Seismic isolation is effective in reducing seismic demand for buildings and decreasing seismic damage costs. Today the concept has matured into a practical reality and is taking its place as a viable alternate to conventional (fixed base) seismic resistant construction. This study, three bracing frame and three spacial moment frame were modeled and analyzed and the capacity curve wase plotted.The finaly, response modification Factors  for steel frames equipped with base isolation were compiled as a table.Finally, based on the results of the analysis, it was observed that the structures equipped with the surface separator have a more obtuse curve than the non-separating state. Manuscript profile
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  5 - Spatial Analysis and Handling of High-rise Buildings from Reinforced Concrete Core Internal Resistant Pipe System under Dynamic Loads on the Tube
  Saeed Ghani Shayesteh Ashkan khodaBandehLou
  20.1001.1.23456310.1398.16.3.2.1
  The construction of high-rise structures around the world is rapidly increasing and this trend has been accelerated following the rapid economic growth and expansion of cities and increasing demand for space in populated areas. As these skyscrapers reach higher heights, More

  The construction of high-rise structures around the world is rapidly increasing and this trend has been accelerated following the rapid economic growth and expansion of cities and increasing demand for space in populated areas. As these skyscrapers reach higher heights, they become a symbol of the power and superiority of technology advancement and economic development. Therefore, the use of new structural systems and modern construction technologies with the aim of reaching taller buildings considered by designers and engineers. In this study, a 26-story structure with 3-story underground with retaining walls is required to design against the lateral soil force of the surrounding area, that has a dual core system with tubular core modelled and dynamic analysis was performed under the influence of earthquake lateral force, and extent of lateral displacement of the structure and changes in force applied to its components were investigated in Sap2000 software. The tube in tube system indicated good performance against gravity and lateral forces and the maximum lateral displacement of the floors was within the permissible range due to the code and height of the structure concerned. Manuscript profile
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  6 - Investigation of seismic Fragility and collapse capacity of RC Moment Frames Considering the increase of stiffness of the column relative to the beam under far and near field earthquakes
  siamak saboonchi ashkan khodabandehlou
  10.30495/civil.2023.699218
  20.1001.1.28210999.1401.19.4.4.1
  In the present research, the seismic fragility and collapse capacity of concrete moment frames have been investigated by considering different ratios for the weak beam-strong column rule in the optimization process in the performance-based design framework. In order to More

  In the present research, the seismic fragility and collapse capacity of concrete moment frames have been investigated by considering different ratios for the weak beam-strong column rule in the optimization process in the performance-based design framework. In order to implement performance-based optimization, the center of mass metaheuristic algorithm has been applied in this research. The philosophy of design approach based on performance and even traditional design methods allows the structure to suffer damage facing strong and relatively strong earthquakes. Therefore, in order to estimate the level of safety of the structure against earthquakes, it seems necessary to use quantitative indicators of seismic safety and the collapse capacity of the structure. In order to predict the collapse capacity of each optimal structure, using incremental dynamic analysis, the modified collapse safety margin ratio under far and near fault earthquakes has been calculated. Two examples, 3-span three and six floor frames have been studied in this research, which are designed in the performance-based optimization framework and considering the coefficients of 0.8, 1.2 and 1.6 to control the weak beam-strong column rule in the optimization process. The results indicate that increasing the rigidity of the column compared to the beam in this research actually affects the ductility of the structure, and by choosing structures with greater rigidity of the column compared to the beam, it leads to an increase in the collapse capacity and a decrease in the fragility of the structure. Manuscript profile
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  7 - Investigation of Nonlinear Seismic Behavior of High-rise Reinforced Concrete Buildings and their Improvement by Viscoelastic Dampers
  Faraz Kazemi ashkan khodabandehlou
  10.30495/civil.2022.689974
  20.1001.1.23456310.1400.18.4.6.1
  Owing to the destruction of high-rise buildings during recent earthquakes, the use of a structural system of reinforced concrete moment frame with viscoelastic damper causes a loss of seismic energy and consequently reduces lateral displacement. In this study a high-Ris More

  Owing to the destruction of high-rise buildings during recent earthquakes, the use of a structural system of reinforced concrete moment frame with viscoelastic damper causes a loss of seismic energy and consequently reduces lateral displacement. In this study a high-Rise, 20-Storey, three-dimensional reinforced concrete frame with 8 Models, of which 4 models with moment frame structural system and 4 models with moment frame + viscoelastic damping system in two directions of X, Y located in the high seismic zone (A=0.3g) on the soil type III is considered. The aim of the present study is to investigate the horizontal lateral displacement (absolute and relative) of the stories, the base shear of frames under gravity loads, and lateral loads of the earthquake.  In order to modeling the viscoelastic materials, the Kelvin-Voigt model and to determine damping ratio(ζ) of frames with viscoelastic damper, stiffness coefficient (Kv) and damping coefficient (Cv) of viscoelastic dampers, the modal strain energy method have been applied. For seismic analysis of models without and with dampers, dynamic analysis of nonlinear time history via direct integration and modal (FNA) methods have been utilized, respectively.  Geometric modeling of all frames was done using the SAP2000-V15 software. The results indicate that with increasing span length (model 2 compared to model 1 and model 4 compared to model 3) and increasing the height of stories (model 3 compared to model 1 and Model 4 compared to model 2), the maximum absolute lateral and relative displacement of stories, and base shear along with X, Y without and with viscoelastic damper have an increasing trend. Also, the maximum percentage increase of the mentioned models with damper compared to without damper along with X, Y has decreased Manuscript profile
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  8 - The Effect Of Soil And Structure Interaction On High-Rise Reinforced Concrete Buildings With Internal Resistant Core Tube In Tube System And With To Consider Nonlinear Dynamic Analysis
  Armin Razzaghi ashkan khodabandehlou
  20.1001.1.23456310.1399.17.3.6.2
  This research are considered and analyzed threedimensional  high rise building three frames of 28-story reinforcedconcrete in each direction X,Y structural structure of a tube in tube,In the zone of high relative risk(A=0.3g),With fixed number and  bays the le More

  This research are considered and analyzed threedimensional  high rise building three frames of 28-story reinforcedconcrete in each direction X,Y structural structure of a tube in tube,In the zone of high relative risk(A=0.3g),With fixed number and  bays the length,different heights and types of soil(I, III), Once without affecting soil-structure interaction Once again, the effects of soil-structure interaction are considered and analyzed. The purpose of the present study is to determine the maximum lateral displacement frames floors of gravity loads(dead,live)and earthquake loads. In order to analyze the structure of the structurethe soil-structureintraction impact of the substructure is assumed to be used for the  modeling of the sub-surface soil from the cone model,the structure of the structure and the determination of the dynamic hardening coefficient and  damping coefficient  soil of the discrete model based on the cone model in the homogeneous space stream.In order to analyze earth quake loads  in the studied models,a  dynamic analysis of the nonlinear time history of the modal method under seven  accelerations accelerations.The geometric modeling of the all frames with shear walls in the SAP 2000-V17 software package was performed.The results show that with increasing elevation of floors(model 1 to 3),the maximum lateral displacment floors on type I soil in the direction of X increase in the direction Y is significant increase,in model ,in the model 2 to 1by changing the type of soil type, the maximum lateral displacment floors with out and with Soil-Structure intraction in the each two direction is dramatic increase Manuscript profile
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  9 - Evaluation of Nonlinear Seismic Behavior of Reinforced Concrete Flexural Frames with Special Ductility with and without Viscous Dampers on the Floors Level
  siamak barmaki ashkan khodabandehlou
  10.30495/civil.2023.708011
  The main goal of this research is to evaluate the nonlinear seismic behavior of special RC moment with and without viscous dampers at the floor level. In this research, 2 high-rise three-dimensional RC building frames of 12 and 16 stories, each frame with 8 models, 4 mo More

  The main goal of this research is to evaluate the nonlinear seismic behavior of special RC moment with and without viscous dampers at the floor level. In this research, 2 high-rise three-dimensional RC building frames of 12 and 16 stories, each frame with 8 models, 4 models with and 4 models without viscous damper at the floor level, located in the area with High seismicity on type 3 soil is considered. In order to seismic analysis of frames with and without viscous dampers, nonlinear static analysis method was used according to the second appendix of Iran earthquake regulations, fourth edition. The initial dimensions of the structural elements of the studied frames and the thickness of the roof slabs have been determined in ETABS-V15 and SAFE2014 software, respectively, and finally, modeling, gravity and lateral loading, and nonlinear static analysis of the studied frames have been performed in the SAP2000-V19 software. The results show that the change in the sections of beams and columns from square to rectangle in frames with and without viscous damper causes an increase in the relative lateral displacement of the floors, as well as an increase in the number of openings along the Y axis (model 1 compared to 3), and an increase in the length of the opening along the Y axis (model 1 Compared to 4), in frames with and without viscous damper, it reduces the absolute lateral displacement of floors. Manuscript profile
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  10 - The effect of far- and near-field earthquakes on the collapse capacity of performance based optimization of RC moment frames
  siamak saboonchi ashkan khodabandehlou
  10.30495/civil.2023.701926
  20.1001.1.28210999.1402.20.1.7.5
  Performance-based design is a new approach to topics of the seismic design of structures, which unlike the traditional methods of force-based design, is based on changing the location of the structure. The use of this approach in the process of structure design results More

  Performance-based design is a new approach to topics of the seismic design of structures, which unlike the traditional methods of force-based design, is based on changing the location of the structure. The use of this approach in the process of structure design results in the access to structures with proper performance and an acceptable level of reliability. The main goal of this contribution is to investigate the impact of near- and far- field earthquakes on the collapse capacity and fragility of performance based optimization of RC moment frames using the center of mass meta-heuristic algorithm. Push over analysis has been utilized in the optimization process to control the responses of the studied frames at functional levels and incremental dynamic analysis has been used to evaluate the fragility of the obtained optimal frames. According to the results for the collapse margin ratio and the adjusted collapse margin ratio for the 3-, 6-, and 12-story frames, it is indicated that the collapse margin ratio and therefore the seismic safety under far-field earthquakes are 7%, 16%, and 8% higher than those of the near-field earthquakes, respectively. In other words, the optimized frames in this study against near-field earthquakes have low seismic safety and more fragility than far-field earthquakes. Manuscript profile