The Earthquake Engineering Online Archive

Computational procedure for inelastic finite element analysis

Chi, Hung-Ming; Powell, Graham H.

UCB/SESM-1973/02, Dept. of Civil Engineering, University of California, Berkeley, 1973-01, 183 pages

This report is concerned with the effects of material nonlinearity. The aim of the research is to explore computational procedures, to determine which procedures are likely to be most efficient and most accurate, and to provide detailed documentation of the computational sequence. A variety of solution procedures accounting for plasticity are reviewed but no new theoretical principles are established herein. The flow theory of plasticity is reviewed and incremental stress-strain relationships are derived. The application of the incremental stress-strain relationships in the formulation of the tangent stiffness matrix for an axisymmetric solid is considered along with the "state determination" problem. In addition, the unbalanced load on the structure, which is a measure of the accuracy of the solution, is determined. The logic of a computer program to apply the proposed solution procedure is described. The results of analyses of an extensive series of example structures are presented and conclusions on the relative efficiency of several alternative computational procedures are drawn.

Available online: http://nisee.berkeley.edu/documents/SEMM/SEMM-73-02.pdf (6 MB)