Hi Hamid Reza Attar,

I didn't understand the sign of which value you meant. Suppose that it is one of the abaqus variables, say PE11. Then you can create new field output via Tools->Cteate Field Output->From Fields... Schematically (the actual expression in the expression text field will be more complex) it looks like

PEEQ *PE11/(abs(PE11)+1E-15).

You can visualise this field using the temporary step of the current ODB named "Session Step". Of course, PE11 is taken just for example.

Hi Victor, thanks very much for your reply. Which variable to select to provide the sign was precisely what I was asking in my question.

I have a feeling that the Pressure stress might be a suitable variable, but if I multiply the sign of this by PEEQ, does that give any physical meaning to the signed PEEQ?

Could you identify a suitable variable to use as the sign, applied to PEEQ? Such that PEEQ goes from positive to negative through the thickness but still maintains it's physical meaning.

Thanks very much.

The value of (1+MAX_PRINCIPAL)*(1+MID_PRINCIPAL)*(1+MIN_PRINCIPAL)-1 for LE could be considered as an indicator of relative volume change (>0 for expansion and

Since the U-channel seems to generate strains in 1 direction mainly a simple interpretation with strain output "E" can be appropriate (as far as I see from the screenshot)?

PEEQ is a measure for the equivalent strain, a similar measure as von Mises stress for stresses hence it is just better to take for example the output "E" for small strains in Abacus if you need to show contraction and expansion.

As far as I can guess, a contraction and expansion by a change in sheet thickness or geometric length of the U-channel are not relevant to consider.