الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Residual deformations of buckling restrained braced frames (BRBFs) are expected to be excessive under seismic loading owing to the low post-yield axial stiffnesses of the buckling restrained braces (BRBs). Recent studies have suggested shortening the BRB yielding-core lengths to improve their axial stiffnesses. The purpose of this study is to evaluate the seismic responses of low- and medium-rise BRBFs with different BRB yielding-core lengths. Static pushover and dynamic time-history analyses were performed on 3-, 6-, and 9-story prototype buildings equipped with BRBs with short, medium, and long yielding-core lengths. The performance parameters evaluated in this study include the maximum and residual roof drift ratio (RDR), the maximum and residual story drift ratio (SDR), and the BRB axial strain demands. The results of this study reveal that short-core BRBs have the potential to enhance the seismic response of BRBFs because they are shorter in length and possess higher pre- and post-yield stiffnesses. The mean maximum and residual lateral drift parameters of short-core BRBFs calculated under strong earthquakes are generally lower than those of long- and medium-core BRBFs. With respect to the axial-strain demands, the results showed that short-core BRBs generally exhibit higher strain demands than long- and medium-core BRBs.