Fundamental Elasto-Plastic Finite Element Benchmarks

This paper on "Fundamental Elasto-Plastic Finite Element Benchmarks" was presented at the International Conference on Quality Assurance and Standards in Finite Element Analysis - 22-25 May 1989, Stratford-upon-Avon, England.

Summary

One of the products of the NAFEMS Non-linear Working Group has been the specification of a set of fundamental benchmark tests for elasto-plasticity. The tests involve very simple geometric specimens in two dimensional plane stress and strain, axisymmetry and three dimensions. Loading is by prescribed displacement over, in most tests, all the degrees of freedom so that the resulting equilibrium solution is well-posed, and so the tests concentrate on the constitutive models: geometric non-linearities, rate and temperature effects are excluded. Different hardening models are considered, as perfect plasticity, isotropic and kinematic hardening.
Target solutions are identified in all cases and a reappraisal of the usefulness of these tests is made. Two finite element programs are used in the above evaluations, one from Swansea University plus BERSAFE, a commercially-available non-linear code developed at BNL.