Cyclic Elastoplastic Large Deflection Analysis of Thin Steel Plates

Abstract

This paper deals with the elastoplastic large deflection analysis of thin steel plates subjected to in-plane cyclic compression and tension using the finite element method. The modified two-surface plasticity model, recently developed by the authors, and the approximate updated Lagrangian description of motion are employed, respectively, for material and geometrical nonlinearities in the elastoplastic finite element formulation for plates. The plate element is implemented in the computer program FEAP used in the analysis. The formulation accounts for important cyclic characteristics of structural steel within the yield plateau and hardening regime, such as the decrease and disappearance of the yield plateau, reduction of the elastic range, and cyclic strain hardening, as well as the spread of plasticity through the thickness and plane of the plate. The cyclic elastoplastic performance of the formulation was found to be good when compared with the results obtained from other material models. Based on the results of an extensive parametric study, the effect of loading history and some important plate parameters on the hysteretic behavior of thin plates is discussed and evaluated.