Improvement and Retrofitting of Reinforced Concrete Buildings by Using Steel Bracing

In our country, most of the existing concrete buildings were designed and implemented based on the old regulations and given the tendency of researchers and experts in designing based on performance (PBD), the issue of whether concrete building that are designed based on the first edition of the 2800 Regulation in terms of performance level meet the criteria of adoption of 273 and 356 FEMA instruction and consequently the improvement instruction of Iran or they need retrofitting, reveals to use the importance of seismic evaluation of concrete structures more than in the past. Accordingly, in this article as well, first concrete buildings in a mold of ductile frame system with medium ductility, on the basis of the first edition of 2800 Regulation were designed and based on 273 and 356 FEMA instructions and improvement instructions of Iran were in terms of being seismic evaluated.