FEM-computation of load carrying capacity of highly loaded passive components by direct methods

Limit and shakedown theorems are exact theories of classical plasticity for the direct computation of safety factors or of the load carrying capacity under constant and varying loads. Simple versions of limit and shakedown an alysis are the basis of all design codes for pressure vessels and pipings. Using finite element methods (FEM), more realistic modeling can be used for a more rational design. The methods can be extended towards optimum plasti c design. In this paper, we present a first implementation of limit and sha kedown analyses for perfectly plastic material into a general purpose FEM p rogram. Limit and shakedown loads are obtained for a square plate with a ho le and for a thin tube. Interaction diagrams are calculated and the results are compared with known analytic solutions. (C) 1999 Elsevier Science S.A. All rights reserved.