Parametes from J2 plasticity model

[Ashok]

Hi,
Can somebody tell me about the parameters in J2 plasticity.
nDMaterial('J2Plasticity', matTag, K, G, sig0, sigInf, delta, H)

What are delta and H ?
How to calibrate them from experimental stress-strain curve ?

[mhscott]

The math equations do not render, but delta is an exponential strain hardening parameter and H is a linear strain hardening parameter

https://opensees.berkeley.edu/wiki/inde ... y_Material

For linear strain hardening, you can set delta=0 then select H to match a desired plastic stiffness like what's described here:

https://portwooddigital.com/2021/05/19/ ... libration/

[Ashok]

Thanks a lot !
I tried it - but it shows the message:
"More than 25 iterations in constituive subroutine J2-plasticity "