List of Articles near-fault earthquake

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  1 - Estimation of Behavior Coefficient of steel eccentrically braced frames (EBFs) under Near-fault Pulse-type Earthquakes using Particle Swarm algorithm
  Seyed Abdonnabi Razavi Navid Siahpolo Mehdi Mahdavi Adeli
  Elastic analysis of structures creates basic shearing forces and stresses that are significantly larger than the actual responses of the structures. By entering the inelastic domain, the structure can absorb and resist a large amount of earthquake energy. On the other h More

  Elastic analysis of structures creates basic shearing forces and stresses that are significantly larger than the actual responses of the structures. By entering the inelastic domain, the structure can absorb and resist a large amount of earthquake energy. On the other hand, nonlinear analysis of structures requires time-consuming and voluminous computational operations, so in most of the codes, a simple and appropriate method called equivalent static method is presented to achieve a reasonable answer to the nonlinear behavior of the structure (without performing a nonlinear analysis). Therefore, due to the importance of ductility in the absorption of seismic energy, the computational forces caused by the earthquake are reduced by introducing the coefficient of structural behavior, R. In this paper, an extensive database consisting of 12,960 eccentrically braced frame (EBF) structures with varying story numbers of 3, 6, 9, 12, 15 and 20, three types of column stiffness and three degrees of bracing slenderness was designed and analyzed under 20 near-faults pulse-like earthquakes. To generate the estimated relation R, 6769 data were interpreted using particle swarm algorithm. The results of a correlation of 0.86 in the test data presented the accuracy of the proposed relation. Manuscript profile
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  2 - Extension of Genetic Algorithm Relationships for Estimating the Global Ductility of EBFs under Near-fault Pulse-type Earthquake
  Seyed Abdonnabi Razavi Navid Siahpolo Mehdi Mahdavi Adeli Mohamad Bahmani Seyed Afshin Mohebi Bahram Barri
  10.30495/civil.2021.686510
  Ductility of the structure is the ability to withstand trans-elastic deformations of the structure without a significant drop in strength. Examining the results of past earthquakes and the damage to structures makes its ductility and supply in the structure an important More

  Ductility of the structure is the ability to withstand trans-elastic deformations of the structure without a significant drop in strength. Examining the results of past earthquakes and the damage to structures makes its ductility and supply in the structure an important issue. In this paper, in order to take advantage of the strengths of the design method based on the performance and computational ease of force design methods, frames with 3, 6, 9, 12, 15 and 20 floors have been considered. Then, a large database consisting of 12960 data was generated and designed with the purpose of 3 types of column stiffness and 3 degrees of bracing thinness and analyzed against 20 earthquakes near pulsed faults for 4 different performance levels. Finally, using the genetic algorithm, the experimental relationships corresponding to the coefficients of behavior, global ductility and link beam ductility are presented. The proposed relationships are influenced by geometric characteristics such as the number of floors, the stiffness ratio of the columns, the slenderness of the braces, the length of link beam, and the ductility levels. The results of seismic design using the proposed relationships on structures outside the range of the defined database, in comparison with the force methods, show the accuracy of this method in estimating the seismic needs of divergent bracing frames. It can be concluded that based on the production relations of the database, and the validation of the production relations, the results of the structural design by the resulting relations have an acceptable validity. Manuscript profile
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  3 - Seismic Performance of RC Frames Equipped with Zipper Braces Subjected to the Near-field and Far-field Earthquakes
  Seyyed Ramin Abtahi Babak Behforouz
  10.30495/civil.2021.687433
  In recent years, near-fault earthquakes have received more attention due to their variable frequency nature, pulsing motion, and causing incremental damage. On the other hand, due to the abundance of concrete structures in Iran, more than any other structures, they are More

  In recent years, near-fault earthquakes have received more attention due to their variable frequency nature, pulsing motion, and causing incremental damage. On the other hand, due to the abundance of concrete structures in Iran, more than any other structures, they are at risk of damages caused by near-fault earthquakes. This issue clearly indicates the necessity of using new lateral bracing systems in RC structures. One of the lateral bracing systems is the combination of Chevron braces with zipper elements. Owing to this issue, the main purpose of this study is to investigate the seismic performance of RC frames equipped with zipper braced elements under near-fault earthquakes. Therefore, seven far-fault and seven near-fault earthquake records and three RC frames of 3, 6, and 9 floors with and without considering zipper elements were selected. Then, RC frames were designed using linear static analysis, after which all frames were analyzed by dynamic nonlinear time history analysis. After performing the analysis, the results such as total displacement, relative displacement, story shear, and plastic hinge formation were compared. The results of this study present that the zip-shaped elements have significantly succeeded in transferring asymmetric loads of the lower story braces to the upper stories and have prevented the creation of a soft story in the first height level of the structure. Finally, the comparison of the results ehibits the significant effect of the distance from the fault on the overall and relative deformations of the structures with increasing the height of the stories Manuscript profile
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  4 - Evaluation of the Performance of Visco-elastic Dampers in Near-fault Earthquakes using Nonlinear Time-history Analysis
  Rasoul Sabe-ahd Kolsum Jafarzadeh Mohammad Ali Lotfollahi-Yaghin
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