Seismic Performance of Steel-Braced Frames with an All-Steel Buckling Restrained Brace

In terms of weight and curing of mortar in the brace core, an all-steel buckling-restrained brace is considered an improved type of common buckling-restrained brace. In this study, a new type of all-steel buckling-restrained brace was introduced; it was made up of three parallel plates that were connected through a Z-shaped profile. Cyclic analysis was conducted through a software program for finite-element analysis. First, the numerical model was validated through an experimental sample, and the finite-element numerical model was introduced after achieving a desirable match with the behavior of the model. The variable parameters of this analysis were the overlap length of the plates and the section depth of the brace. Determination of the nonlinear modeling parameters of the brace was followed by comparison of two modes of the frame with typical convergent X-shaped braces and buckling-restrained braces for 5-, 10-, and 15-story structures through pushover and nonlinear time-history analyses. The obtained results suggest that the new buckling-restrained brace maintained the structural-life safety performance level.