Multi-step analysis of thin shell

[FEAnalyst]

@JimmyLee1004

The F_initial position is reset when a new step starts.
I currently need to manually reposition it using displacement/rotation boundary conditions and amplitude definitions.
Is there a way to continue the analysis using the deformed configuration from the previous step without redefining boundary conditions?

Check this thread (especially the last point there): Understanding multistep analyses

@JimmyLee1004

However, I could not find a way to change rigid body constraints between steps.

There’s no such option. Only contact pairs can be deactivated.

@JimmyLee1004

Additionally, I suspect the film may exhibit bistable buckling behavior depending on the fixed position. Can PrePoMax handle this kind of problem?

Yes, but you need to enable Nlgeom for that and avoid shells + rigid body constraints + Nlgeom because it leads to non-convergence. As a workaround, you can just use solid elements at least for the regions with rigid body constraints, but it seems that you already did that.

@JimmyLee1004

Unfortunately, due to company security policies, I cannot upload the PMX file.

Even via a private message ?