Buckling Capabilities of Geos

[imanook]

Hello GEOS team and community,

I am working on simulating a lab experiment and would like to confirm the best approach for modeling it in GEOS.
I am working on a 2D axisymmetric model of a core sample (porous medium). The goal is to perform a stability (buckling) analysis to find the critical axial load under mechanical effects. The model is subjected to a mechanical axial load and in terms of the boundary condition, the system is undrained (no-flow).

My questions are:

1. Is there a recommended solver structure for this type of non-linear buckling analysis?
2. Are there any best practices or specific considerations we should be aware of when setting this up?

Given the slender geometry of our sample, we anticipate that geometric nonlinearity (i.e., the change in stiffness as the core deforms) could be significant. A linear analysis might overestimate the critical load.

Thanks,

Regards,
Iman