Seismic evaluation of reinforced concrete moment frames retrofitted with steel braces using IDA and Pushover methods in the near-fault field

Document Type : Research Article

Authors

1 استاد دانشگاه سمنان

2 Phd Candidate, civil faculty, semnan university

Abstract

One of the methods for seismic retrofitting in reinforced concrete structures is the use of steel braces. In this paper, the effect of concentric and eccentric bracing systems on the seismic performance of dual reinforced concrete building systems was investigated under seven near-fault earthquake records. Following this, two reinforced concrete frames with 10-story and five spans were designed and analyzed using the incremental dynamical analysis (IDA) method, where the braces were placed in the 1st and 5th spans. The results indicated that the bearing capacity of the reinforced concrete frame by using CBF and EBF braces increases up to 2.3 and 2 times, respectively. The use of EBF brace in a reinforced concrete frame reduces the amount of the base shear applied to the structure up to 7 times compared with the CBF frame. Approximately, the displacement of the roof in the EBF frame is less than the CBF frame. Furthermore, the ductility of the EBF frame against earthquake records causes an increase in the performance level of structure to the immediate occupancy (IO).

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References

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Amirkabir Journal of Civil Engineering
Volume 52, Issue 5
August 2020
Pages 1127-1142

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