Seismic Performance of Reinforced Concrete Braced Frames under Far- and Near-Fault Earthquakes

In this study, the seismic performance of reinforced concrete (RC) frames equipped with two different kinds of braces, i.e. special concentric braces (SCB) and buckling restrained braces (BRB), was investigated. Eight frames with various numbers of stories (four-, eight-, 12- and 16-story for each dual system) were designed on the basis of a code-design method for a high risk seismic zone. Nonlinear static and dynamic analyses of the frames have been performed using OpenSees software. To consider different ground motion characteristics, an array of time-series from ordinary far-fault records to near-fault motions with forward-directivity and fling-step effects was employed. Results from the analytical study indicate that the utilized design method for both dual systems was reasonable and the mean maximum drift of the frames under all ground motion sets were in acceptable range. Near-fault motions, especially records with forward-directivity effects, imposed higher demands than far-faults. For low-rise frames structural system of RC-SCBshowed better performance than RC-BRB, while better performance of the other frames were shown for RC-BRB system.