I am trying to understand the details of the fully implicit backward Euler return algorithm that is often used when integrating the elastic-plastic constitutive equations. There is a nice explanation in the book of Ted Belytschko and a few papers on the subject (I liked mainly Dorgan & Voyiadjis, Arch. Mech. 59, 2007). I managed to rederive it on the paper and so I understand the concept well. Now I face the problem of reducing this algorithm to the plane strain case. There is a paper of Simo & Taylor (Int. J. Num. Meth. Eng. 22, 1986), where they mention at the bottom of the first page that this can be done trivially and give reference to a report which I could not find. At the same time, they argue that plane stress puts non-trivial constraints on the algorithm, which is something I would anticipate also for plane strain. I would be grateful for any comments or links to web/papers where I could find some help. Also, does somebody have the report of Hallquist: Rep. UCID-19677 of the LLNL (1984) in pdf ?
Roman