Engineering Transactions, 33, 1-2, pp. 173-203, 1985

Тhе Post-Yield Analysis of Rigid Plastic Beams Columns and Frames

M.K. Duszek
Institute of Fundamental Technological Research, Warszawa
Poland

T. Łodygowski
Institute of Fundamental Technological Research, Warszawa
Poland

In: the paper the influence of second-order geometrical effects on the post-yield behaviour of plastic structures is considered. The presentation is limited to the purely mechanical (isothermal) theory and quasi-static deformation processes. The problem considered is illustrated by means of the examples of rigid-plastic beams with various kinds of partial end fixity, the rigid-plastic columns loaded by vertical and horizontal forces and multi-story portal frames. It is demonstrated that plastic deformations may result in changing the boundary conditions in such a way that the stabilizing effect of tensile axial forces is reduced. By making the proper choice of sonie factors unstable mechanisms and catastrophic collapse can be avoided.
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