Multiple load cases in different steps

[VaidehiChennubhotla]

Hi,

I have 4 load cases which I want to run in 4 steps in the same model of abaqus. While activating and deactivating necessary loads, contact pairs and boundary conditions. I am running a static linear analysis. Should I have the 4 load cases in 4 consecutive steps or have unloading steps in between? So that total of 8 steps . Will consecutive steps affect the deformation value in each step?

 

[Mustaine3]

Assuming the boundary conditions are not different in it's location for all loadcases, then it is the best to create one linear step and create 4 loadcases within that step.

 

[FEA way]

General static step uses the state of the model from the previous general static step as initial state. You can use static linear perturbation steps instead. Such step uses the state of the model only from the previous general static step. So an analysis with 4 linear perturbation steps will work in the same way as Load Case feature available in the Load module. You can use one of these two approaches but the latter should solve faster.

 

[VaidehiChennubhotla]

Thank you guys for the quick reply.
Hi Mustaine,
I have different load plates. So the contact pairs also should be changed. The linear perturbation seems to allow choosing only the load and boundary conditions but not the contacts. Is there any way to apply selected contact pairs even within the linear perturbation load cases ?

Will linear perturbation with load case feature carry the loads from one load case to the next ? or will it be independent results ?

 

[VaidehiChennubhotla]

Hi FEA way,

The 4 static linear perturbations doesn't seem to allow me to deactivate the contact pairs in successive load cases. And it is showing as built into base state both in interaction module and step module. Will the load cases give results independent of previous load case ?

 

[FEA way]

In static linear perturbation steps contact status is assumed to remain unchanged (otherwise it would be a source of nonlinearity). Settings specified outside of load cases apply to all load cases.

Load cases give independent results. But you can do the linear combination of results from load cases in postprocessing (using Tools —> Create Field Output —> From Frames).