On the meaning of the "yielded in past" state

General
1

Hi all,

I have long reflected on the meaning of “yielded in past” state and on how I should interpret it in my analyses.
Thanks to this discussion Problems with yielded in past zones, I understood that such state expresses that during the explicit calculation process the zone marked as yielded in past has experienced a stress condition outside of the yield surface. Some stress corrections are involved in the calculation, so the stress point is dragged back to the elastic guess that’s consistent with the plastic criteria. That zone is labeled as yield in the past, but it’s now in elastic state.
I often find this condition reached in almost all the zones of my domain when I switch from an elastic to a plastic model.
Does the achievement of this condition indicate incorrectness in my model? And how should I interpret it if the yielded in past state is attributed to almost all zones of my model?

Thanks a lot for your help.

2

It doesn’t necessarily mean your model is wrong, but it could mean that the properties you set aren’t compatible with your initial stresses. In an in-situ analysis, the yielded elements should be minimal, in most cases.

3

Thank you so much Felipe!
Do you therefore suggest increasing the properties and making the model stronger?