چكيده لاتين :
Concentric bracing is one of the most common lateral load resistant systems in building fram es. and are
applied to many structures due to their manufacturing simplicity and economics. An important defi ciency in the
bracing members is their irregular hysteretic loops under cyclic loading. In order to overcome this problem. it is
advised to restrain braces against buckling under compression. since buckling restrained fram es dissipat e a large
amount of energy. One method to restrain braces against buckling is to cover them with concrete. A proper covering
can prevent the core from buckling and provide similar capacities whether in tension or compression which would
produce regular hysteri c curves. In this study, the behavior ofbuckling restrained braces (BRB) has been investigated
by considering different types of surrounding covers. The steel core is encased in concrete with different coverings. The
cove ring types include steel tubes, PVC pipes. and FRP rolled sheets. Experimental and numerical analyses were
implemented. According to the results, PVC pipes and FRP sheets are suitab le alternati ves to steel pipes. Furthermore.
the behavior of several types ofsteel cores was assessed; since, applying steel with high ductility promot es the energy
dissipation of the brace. Finally. the effect of the separating layer between the steel core and the concrete on the
performance (if bracing was evaluated.
