Simplified Elastic-Plastic Analysis of Stiffened Plates and Space Frames

In this paper two algorithms are presented for approximate nonlinear analysis of stiffened plates subjected to lateral and/or in-plane loads. The stiffened plate is treated either as an equivalent orthotropic plate or as a space frame. The last case corresponds to a discrete beam idealization in which the plate is represented by effective flanges acting together with the stiffeners according to simple beam theory. For plane cases local buckling phenomena are incorporated into the frame model.Three points are believed to be new in this paper:—comparisons between the two models in nonlinear range are made and as a conclusion the necessity of application of both models of real structure is confirmed because of very different results obtained in elastic and elastic-plastic range.—the additivity of elastic and plastic parts of the total generalized displacement is discussed and some error estimates in terms of known Timoshenko beam hypothesis are given,—formulas for modification of effective breadth values tre...