Evaluation of Performance of Reinforced Concrete Frame Retrofitted Using Concentric Steel Bracing

One of seismic retrofitting approach of reinforced concrete (RC) frames is using structural steel brace elements. In current paper some existing moment resisting RC frames with intermediate ductility was designed to withstand seismic loads which were predicted by second edition of Standard No. 2800. In other to evaluate rehabilitated RC frames, models were loaded according to third edition of Standard No. 2800. Analyses of frames show stress ratio in most of columns were exceeded allowable value. Selected RC frames were rehabilitated using concentric inverted V-brace elements. Retrofitted frames were evaluated based on Seismic Rehabilitation Code for Existing Building in Iran. Also formation of plastic hinges and provided performance levels were investigated. Displacement control plastic hinges and performance levels of nonlinear modeling criteria were extracted from Seismic Rehabilitation Code. Results present formed plastic hinges with their performance levels and discus about used seismic retrofitting approach efficiency for hazard level of 10% earthquake probability of acceptance in 50 years.