ABSTRACT
An efficient seismic force resisting system should possess enough strength such that member forces are lower than the factored resistance, supply adequate stiffness to limit the system’s deformation, and should exhibit sufficient ductility. Thus, concentrically braced frames (CBF) are characterized by a very high stiffness-to-weight ratio and limited ductility. As stated in the Canadian standard CSA/ S16-2009, the dissipative zones of the classical CBF systems are located in the brace members which are designed to yield in tension and buckle in compression. However, during the hysteresis response, braces on the verge of buckling lose their buckling strength, which causes deterioration in storey shear resistance.
