Orthotropic elasticity in @Implicitgenericbehaviour

[yy74774]

Hi!
I am a beginner in mfront and would like to ask you about the code in the case of implicitgenericbehavior.
I would like to use mfront to describe the transversely isotropic thermo-poro-mechanical elasto-plastic behavior of Callovo-Oxfordian claystone.

I have written an isotropic elastoplastic model that considers mechanical and temperature loads (in the case of implicitgenericbehavior), and it has proven to be very effective!
Next I would like to extend this model to the anisotropic case, and I would like to start with anisotropic elasticity.

In the implicit case, I successfully modeled using @ComputeStiffnessTensor. But when I use implicitgenericbehavior, this function does not work, so I calculated the items of the stiffness matrix myself and assembled them. This time mfront can create the material behavior, but mtest does not complete the calculation.
In the attachment you can find me my current mfront and mtest code.
Orthotropic_elasticity.zip

For this case, I have the following questions:

1. Is it possible to modify my current code to achieve anisotropic elasticity under implicitgenericbehavior?
2. Is it possible to consider pore mechanics in the implicit case, if this is feasible I think I can do the full material mechanics behavior in the implicit case.

Thanks in advance,
Junfeng

[thelfer]

Dear Junfeng,

Thanks for your interest for MFront.

You may want to use directly the computeOrthotropicStiffnessTensor which is defined in the TFEL/Material/Stiffness.hxx header. I rapidly modified your code to do so, you'll have to adapt the definition of the elastic properties.

I also corrected a mistake in @TangentOperator (you wrote De = De;).

Thomas

ela_ani_generic.zip