Hello everyone!
I still don't really get how multiple general static steps actually work in Abaqus . According to the documentation, "The starting point for each general step is the end of the last general step. Therefore, the state of the model evolves in a sequence of general steps as it responds to the loads defined in each step." and "the state of the model (stresses, strains, temperatures, etc.) is updated throughout all general analysis steps, the effects of previous history are always included in the response in each new analysis step". However, it seems that it's not always the case. For example, linear analysis of a beam subjected to different load in each step (axial, bending, torsion) gives the same results when multiple general static steps are used and when multiple static perturbation steps are used (assuming that load is reset in each step of an analysis with general steps using OP=NEW). Another example is an approach recommended for issues with analyses involving contact and force control - it's often advised to establish contact using displacement control in the first step and apply the actual load in the second step. But, assuming no other nonlinearities than contact (so no NLGEOM or plasticity), won't the stresses accumulate in both steps and thus the results in the second step (with desired force load) will be affected by the results from the first step? Is it the case that the aforementioned quotes from the documentation are true only when NLGEOM or plasticity is included and otherwise the state of the model is not updated and general steps work like perturbation ones?