Performance Levels of Tall and Irregular RC Structures, before and after Reinforcing by Steel Bracing, under Nonlinear Static and Dynamic Analysis

A building may need retrofitting, based on change of occupancy, change in design codes or deficiencies in design or performance. One method used early years for seismic retrofitting of reinforced concrete frame is by using steel bracing. In this article, first, the formation of plastic hingesand performance levels provided by RC structures are determined by nonlinear static and dynamic analysis; then, these structures reinforced by steel bracing and re-evaluate for performance levels and contrast with first condition. Structures are selected of two different plans in 10- and 15-story. Moreover, the structures of this study, in addition to being tall, are selected irregular in plans to evaluate the effects of the irregularity in results, too. Results show that using steel bracing promoteperformance level and seismic capacity of structures, significantly.