Evaluation of Uniaxial Material Models in Predicting Hysteresis Response of Hollow Structural Section Braces

This paper aims to evaluate the accuracy and efficiency of four uniaxial OpenSees material models, including Giuffré–Menegotto–Pinto, Ramberg–Osgood, Bouc–Wen, and updated Voce–Chaboche, in predicting cyclic inelastic response of hollow structural section braces used in steel concentrically braced frames. A fibre-based numerical model of two hollow structural section braces that have been experimentally tested is constructed and is used to evaluate the capability of these material models in predicting brace cyclic response. In particular, hysteresis response and out-of-plane lateral deformation of the braces are presented and interrogated. The results show a superior performance of the Giuffré-Menegotto-Pinto material model in predicting brace strain-hardening response, first buckling load, post-buckling response, and reloading stiffness. Furthermore, this material model requires a lower computational cost to perform nonlinear analysis.