Boundary, Fixed options

[FEAnalyst]

OP=NEW only affects a given type of feature (*BOUNDARY, *CLOAD and so on). Stress/deformation state may not be preserved in subsequent steps just because the deformation wasn’t permanent (plastic).

Multi-step analysis always maintains previous step deformation?

Yes, that’s how it works in Abaqus and CalculiX. Non-perturbation steps use the state of the model from their predecessors. It’s visible when plasticity is involved. The OP parameter is just to control the boundary conditions, loads and other step-dependent features. When set to NEW (always in PrePoMax), all those features that are supposed to be still working have to be redefined in each step. The remaining ones are removed. When set to MOD, they are carried over automatically and there’s no ne…