عنوان مقاله [English]
The choice of lateral forces resistance system type depends on the composition of the loading, structural behavior, gravity loads transition to the base, architectural design, geometric dimensions, building code restrictions, the amount of lateral forces, the maximum displacement and, etc. Today, the use of concrete dual frames has become very common in many modern structures, including high-rise buildings and building retrofitting. In this study, RC frames with X-shaped steel braces and Concrete X-Shape braces Strengthened with CFRP under Cyclic seismic loading have been investigated. Initially an RC frame in 3 manners such as RC frame, RC frame with concrete X-shaped braces and RC frame with X-shaped steel braces previously tested by Haddad et al. (2015) modeled and analyzed in ABACUS finite element software. Then the results of numerical analysis and laboratory study were compared. The results were fairly well-matched. Finally, after verification of the ABACUS software results, the proper composition of the carbon fiber reinforced polymer (CFRP) retrofitting was studied, and the load-displacement hysteresis diagrams, load-displacement and final load ratios for the proposed samples were compared.