remove BCs at later phases

[rwendner]

We have successfully used the

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Read `FileName' atTime 10. ms
Read `FileName' atStep 10000

commands to add boundary conditions or constraints at a later stage.

Is it possible to remove a defined constraint or contact, e.g. removing the initial formwork support with friction along a beam ?
If so, can you please give an example of the required command ?

How would one delete a beam element / tet list that initially contributes to the system response ?

[zhouxinwei]

At this moment, MARS can not deactivate a contact/constraint/element list at a later stage. We will add it in the next release.

[zhouxinwei]

While we are adding the feature, can you please give a simple example where we can test the logic?

It matters how you define the tet list (e.g. whether it shares nodes with other lists or not).

What's the reason you want to delete just one beam element? due to failure?

[rwendner]

Thank you for your support.

I am thinking about construction stages in modelling certain types of structures. Sometimes, in an early construction stage of e.g. bridges support columns, support beams or even temporary external ties are used which are removed later.

An other example would be multi-physics simulations in which we first want to model the curing conditions with formwork and insulation material etc. At later stages this material is removed and different boundary conditions act on different surfaces (e.g. sun on concrete surface.

[rwendner]

Can you please give an example how you deactivate a mechanical BC.

The read command allows adding BCs but how can I remove one.
For example: I want to apply a mechanical load by describing a displacement (velo) history. After some time the load is removed from support point 1 and applied somewhere else. After that point in time the system should be free to deform in point 1....

a deactivate at time / at step command would be useful - similar to what you introduced for the X LDPM.