Investigating the Interaction of Concrete Moment Frame with Double-K Buckling Restrained Brace and Reducing Residual Deformation as a Dual System

Due to the mechanical behavior of brb braces and concrete frames differing, combining these shows complex behavior in a seismic. It can be used to dual system Brb-Rcf in a concrete moment frame to Improve structural responses. Considering that the behavior of the BRB brace in compression and tension is similar; It can solve the unbalanced force in the Double-K bracing system. The desirability of the Double-K arrangement and its combination with the RCF system as a dual system should be investigated in order to investigate the possibility of using Double-K braces in the RCF system and reducing residual deformations in the case of the dual system. For this purpose, a series of buildings have been analyzed and designed in three structural systems: Rcf, dual frame with brb brace, and bare frame with brb brace according to relevant valid regulations. The pushover and time history analysis have been done, and the capacity curves, base shear, and residual deformation have been investigated and studied. Adding brb braces to the concrete moment frame and dually using them increased the structure's capacity. In the studied structures, from 84% increase capacity in 4-story structure to 94% increase capacity in 12-story structure. This increase is due to the interaction of the concrete moment frame and the brb braces in a dual system. Also, the use of brb braces has made the structure repairable. Because in the concrete structure of the moment frame and the bare frame, the failures were concentrated in the beams and a little in the columns, respectively, but in the structure with Brb-Rcf, the losses were mainly transferred to the braces, which are easily replaceable. Also, the reduction of residual deformation of the structure reduces causes the cost of repair and reconstruction in the structure. Investigations on the formation of hinge showed Due to the Double-K brace that no hinge was formed in the middle of the columns. the losses were mainly transferred to the braces, which are easily replaceable. Also, the reduction of residual deformation of the structure reduces causes the cost of repair and reconstruction in the structure. It was also observed that the structure in combination with the brace in the Brb-Rcf system is designed more economically and with fewer consumables. It is shown in the structure of 8, 4 & 12 story; that the base shear has increased in the frames with brb braces and this increase has been greater in the dual system due to the bending frame and the brb braces. Also, in the hinge, it was observed that the failures of the double structure were less and the types of failures were better according to the replaceability. In general, due to less failure and more base shear that the dual system  structure has, it can be said that the stiffness and resistance due to the interaction of the bending frame and the non-buckling brace has increased, which is the result of the good performance of the dual structure. By comparing the base shear, the suitability of these values ​​with the bearing analysis is clear, so that there also the results showed the increase of the base shear due to the interaction of the frame and the non-buckling brace.