An Application of the Hardening Rule to Plastic Failure Surface Model of Steel Structures

Abstract

Global safety domain against plastic collapse of a perfectly elastic-plastic structure becomes a convex polyhedron, and its whole figure is approximated also by a hyper-ellipsoidal yield surface from a few reference points on the surface. And then, to simplify the non-linear dynamic design procedure, the response analysis with the yield surface models is performed. On the other hands, the response of a bilinear material can be described by a hardening rule, specifying the modification of the yield condition. In this paper, the hardening rule is applied to capture the dynamic behavior of global yield surface model of plastic collapse of bilinear steel frames. And then, the formularization of the hardening rule for yield surface model of structure is represented. The validity of proposed method is checked by comparison with the results of earthquake response analysis usually adopted. And also, this paper provides a new vision of an application of the hardening rule.