The Influence of the Semi-rigid Behaviour of Column Base Plates and Beam-to-Column Joints on the Non-linear Dynamical Response of Steel Portal Frames

摘要

This paper presents a semi-rigid low-rise portal frame non-linear dynamic analysis.rnOne of the main objectives of this work is to propose a modelling strategy tornproperly represent the semi-rigid joint response under dynamic loads implementedrnon the ANSYS finite element software. The developed finite element modelrnincluded the geometrical non-linearity and considered the influence of non-linearrnand hysteretic connections. The updated Lagrangean formulation was used to modelrnthe geometrical non-linearity. Another important investigated issue concerned thernassessment of the structure dynamical behaviour due to the presence of symmetricalrnand non-symmetrical beam-to-column semi-rigid joints and, especially, the columnrnbase plates. The results indicated that the resonance physical phenomenon was notrnreached in the non-linear semi-rigid frames dynamic response. This fact was due tornthe hysteretic damping induced by the energy dissipation of the non-linear hystereticrnloops associate to the modelled non-linear joints.