عنوان مقاله [English]
The experience of past earthquakes has shown that most reinforced concrete structures have been damaged by earthquake-bending frame systems. Also, existing reinforced concrete structures that are designed in accordance with previous editions of seismic regulations are not retrofit in terms of seismic improvement instructions and current valid seismic design codes. Stiffness and less strength of the flexural frame compared to the bracing, shear wall and dual systems require that the increase of the strength and stiffness of the structure as a rehabilitation technical strategy with the strategy of adding steel bracing to the economic, administrative and administrative aspects of the use of the building during the upgrade. To improve the performance and to provide the desired performance level. Steel braces for internal, external and large scale external applications that are used extensively in high-rise buildings are of interest to researchers. In this research, the nonlinear behavior of reinforced concrete structures rehabilitated with steel braces in the form of internal, external and large scale with a number of floors of 4,8,12 and 15 floors (samples of short, medium and high rise buildings) through the pushover analysis has been studied. The results show a significant increase in the stiffness, absorption of the shear and ductility of reinforced concrete structures rehabilitated with large-scale bracing compared to reinforced concrete structures rehabilitated with internal and external braces and less relative displacement.