en Research Paper Research Paper <font size="1" face="Times-Italic"><font size="1" face="Times-Italic"><p align="left">Concentric bracing is one of the most common lateral load resistant systems in building frames, and are</p><p align="left">applied to many structures due to their manufacturing simplicity and economics. An important deficiency in the</p><p align="left">bracing members is their irregular hysteretic loops under cyclic loading. In order to overcome this problem, it is</p><p align="left">advised to restrain braces against buckling under compression, since buckling restrained frames dissipate a large</p><p align="left">amount of energy. One method to restrain braces against buckling is to cover them with concrete. A proper covering</p><p align="left">can prevent the core from buckling and provide similar capacities whether in tension or compression which would</p><p align="left">produce regular hysteric curves. In this study, the behavior of buckling restrained braces (BRB) has been investigated</p><p align="left">by considering different types of surrounding covers. The steel core is encased in concrete with different coverings. The</p><p align="left">covering types include steel tubes, PVC pipes, and FRP rolled sheets. Experimental and numerical analyses were</p><p align="left">implemented. According to the results, PVC pipes and FRP sheets are suitable alternatives to steel pipes. Furthermore,</p><p align="left">the behavior of several types of steel cores was assessed since, applying steel with high ductility promotes the energy</p><p align="left">dissipation of the brace. Finally, the effect of the separating layer between the steel core and the concrete on the</p><p align="left">performance of bracing was evaluated.</p></font></font> Buckling restrained brace, cyclic behavior, Cumulative ductility, energy dissipation, PVC pipe, and FRP sheets 0 0 http://ijce.iust.ac.ir/browse.php?a_code=A-10-145-7&slc_lang=en&sid=1 A.R. Rahai rahai@aut.ac.ir 180031947532846006045 180031947532846006045 Yes M.M. Alinia m.alinia@aut.ac.ir 180031947532846006046 180031947532846006046 No S.M.F Salehi sanam_salehi_m@yahoo.com 180031947532846006047 180031947532846006047 No