Substructuring/Superelement and nonlinear analysis

[irq]

Hi,

I recently had a discussion about FE static nonlinear model reduction and I would like to ask you for the state of the art methods concerning this matter. It is well known that the use of substructuring or sometimes called superelements can significantly save the development and calculation time. The drawback: it is valid for a linear regime. During the nonlinear analysis as the loading increase the stiffness matrices are repeadly revised and the concept of superelement will not work.

What are the current methods to be used for dealing with the boundaries of the substructure for the large assemblies in case of a complete nonlinear project?

Assume:
- the model can not be simplified to a linear case
- there are several teams working on the assembly
- each team is responsible for its own substructure independly.
- the communication follows by exchanging of substructure boundary information.
- we are talking about milions degrees of freedom

Thank you for sharing your experience.

Kind regards,
irq