Incremental Dynamic Analysis of Mid-Rise Buildings with Buckling Restrained Brace Frame System under Pulse-Like Near-Fault Ground Motions

Buckling Restrained Braced Frames (BRBFs) are frequently utilized as seismic force-resisting systems due to their considerable ductility and energy dissipation capacity. While BRBFs have shown reliable seismic performance in extensive experimental and numerical studies under far-field ground motions, research on their performance under near-fault ground motions is limited. near-fault ground motions, characterized by short-duration pulses with high amplitudes, impose greater seismic demands on structures. This study conducts Incremental Dynamic Analysis (IDA) on two ۸- and ۱۲-story BRBF structures under far-fault and near-fault ground motions. Comparison involves confidence intervals of average IDA curves rather than direct curve comparisons due to record selection uncertainty. At ۹۹% confidence, no significant differences are observed. At ۹۵% confidence, a minor difference is noted, while at ۹۰%, substantial differences emerge, with confidence intervals indicating about a ۲۵% difference for the ۸-story and ۷۵% for the ۱۲-story structure. Residual drift comparisons show no significant difference at ۹۹% confidence, a slight difference for the ۱۲-story structure at ۹۵%, and significant differences for both structures at ۹۰% confidence. This suggests the importance of considering near-fault ground motions in assessing BRBF seismic performance, particularly for taller structures.

کلیدواژه ها:

Buckling restrained braced frame ، near-field ground motion ، nonlinear dynamic analysis ، Incremental Dynamic Analysis