An efficient beam-column element for nonlinear 3D frame analysis

Abstract

A three-dimensional nonlinear beam-column element for the simulation of the global and local response of frames under monotonic and cyclic loading conditions is pre-sented. The element belongs to the group of concentrated plasticity models, with plastic hinges located at the ends of the element and described with yield and limit surfaces. The concept of generalized plasticity, originally developed for material plasticity, is extended to force resultants in the element formulation. The element takes into account the interaction of the axial force and the bending moments about the principal axes of the cross section and the hardening behavior. The gradual yielding of the cross section is described by the asymptoti-cal approaching of the limit surface.