الفهرس 
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Abstract
This research investigates the seismic response of buckling restrained braces (BRB) in comparison with hybrid buckling restrained braces (HBRB) under near fault earthquakes known with its extensive structural damages because of the velocity pulses and high frequency contents. Both systems use a bracing that consists of a steel core with a buckling restraining component such as a mortar filled steel tube which leads to a good energy dissipation behavior. The problem of the BRB is the residual displacement after earthquakes because of the yielding of the braces. The HBRB uses a combination of low yield point steel with high strain hardening and high-performance steel which counteracts the low post yield stiffness of BRB. A complex non-linear finite element model (FEM) was used to simulate the real behavior of structures under the combination of both vertical and lateral loads
A parametric study was performed on 3 buildings with different heights -5-, 7-, and 9-story- and different bracing compositions using standard and 2 hybrid combinations. Each building was designed and subjected to pushover analysis and incremental dynamic time history analysis. Time history analysis was performed under 7 near fault ground motions with velocity pulses after scaling and rotating them in fault normal and fault parallel directions.
Seismic code factors such as response modification factor and over strength factor were computed based on the analysis results and compared with design codes. Another comparison was made between the standard bracing and the two hybrid bracing compositions in regard of the max roof drift, residual displacement and inter story drift ratio. Finally, the difference between the effect of fault normal and fault parallel on the structure was illustrated. Based on these comparisons number of considerations were recommended to be taken in dealing with BRB and HBRB and generally for building near active faults.