الفهرس 
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Abstract
In the past few decades, buckling-restrained braces (BRBs) have become increasingly popular as a lateral force resisting system because of their capability to provide strength, stiffness and energy dissipation to building structures. Up to date, the Egyptian code has no specifications for estimating the response modification factor (R-factor) of structures equipped with BRBs. The only available alternative for BRB design is to use the R-factor of conventional bracing which is equal to 4.5. This study evaluates the R-factors for low to mid-rise buckling restrained braced frames (BRBFs) designed according to the Egyptian code. Three BRBFs with 3, 6 and 12 stories are designed with R-factor of 4.5. The actual R-factors of the frames are evaluated by conducting static pushover and earthquake time history analyses. The results obtained in this study indicate that the R-factor values for the braced frames considered in this study vary from 5.0 to 13.5 in case of static pushover analysis and from 6.7 to 9.1 in case of earthquake analysis. These static and dynamic ranges of R-factor are higher than the Rfactor of 4.5 specified by the Egyptian code for the design of braced steel frames. The Rfactor for all the design cases is equal to 5.5 under earthquake loadings and 6.1 for the case of static loading conditions. It is recommended to use R of 5.5 for the design of steel BRBFs in Egypt.