Efficient integration technique for generalized viscoplasticity coupled to damage

✍ Scribed by Magnus Johansson; Rolf Mahnken; Kenneth Runesson

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 264 KB
• Volume: 44
• Category: Article
• ISSN: 0029-5981
• DOI: 10.1002/(sici)1097-0207(19990420)44:11<1727::aid-nme568>3.0.co;2-p

✦ Synopsis

A generalized viscoplasticity theory, with kinetic coupling to damage, was presented by Johansson and Runesson. 1 This theory, which is based on the Duvaut-Lions' concept of viscoplastic reguralization, includes the (unconventional) concept of dynamic yield surface that is approached asymptotically at inÿnite loading rate. In this paper, we extend the model concept to include Microcrack-Closure-Reopening (MCR) e ects. Primarily, we deal with the issue of e cient integration and iteration for computing the stress (and other state variables) within an strain-driven format. In particular, we demonstrate the e ciency of a novel 'multi-level' Newton-like iteration algorithm for the model problem involving von Mises quasistatic yield surface with non-linear mixed hardening. The Algorithmic Tangent Sti ness (ATS) tensor is derived and the model is implemented in the commercial FE code ABAQUS.