Importance of Isotropic Hardening in the Modeling of Buckling Restrained Braces

Abstract

The seismic response of buckling-restrained braces has often been modeled as elastic plastic with kinematic hardening or, even more simplistically, as elastic perfectly plastic. The use of these models has not raised particular criticism because of the lack of models able to represent isotropic hardening with acceptable accuracy and reliability. In recent years, the effect of isotropic hardening has been included in some more refined models of the seismic response of buckling-restrained braces. One of these refined models is considered in this paper to assess the effectiveness of some common models in which the effect of the isotropic hardening is not taken into account. A comparison is made on single-story and multistory structures subjected to natural and artificial accelerograms.