Substructure saving

[medo]

On a large RC model with more than 230.000 FE which consist of Bars and Panels (Slabs and Walls) the design of RC elements according EC2 last 'forever' or more than 6 hours. I noticed that if I save a substructure from that model (e.g. bars only) the design finishes in less than 5 minutes.

When trying to save substructure with all panels only the Status bar displays Results: Out-of date although the results are available in the original model and in the substructure with bars only.
If I save sustructure with one panel thickness, then the Status bar displays Results: Available which is Ok. Then during the design almost half of the panels have errors: 'Incomplete results for panel no.xx' and 'Incorrect reinforcement direction for panel no.xx' Also, after the design finishes, the Status bar displays Results:none and no Reinforcement Maps can be presented.

When design is perfomed on the original model for the panels which were marked as with errors I do not obtain any problems.

Why this happens? Is there any way to speed up calculation of plates and shells?

[medo]

Any resolution to this?

[length zero]

Why do you want to devide model in two parts which conains panelas in one side and bars in other side.
If u have make calculations of global model ( bars and panels) for calculations of elements jou select some of desired elements (panels or bars) and design that for required or provided reinforcements.

"""I im curious to know how do you divide model in two parts.
If u leave the bars only in model or panels only in model this two models are totally different from physical real model."""

As for me wen i have large FE models i use this aproach:
To perform an globala analysis, like eigen values, modal,RS spectrum or to obtain results for global displacements of structure , and oother type of global results , i reduce the size of FE in slabs or panels and ( especially in slabs) an finally i have reduced number of Finite elements.My model performs so fast,\.

When i Want to analysis or design Flor panels i make an seperate model with only geometry of slab with walls of one story, in that case i increase the number of Finite elements and also is lika as detailed analysis of slab.

The reason for it is that the results from global analysis do not afect any great change into results( Moments, shears,.., reinforcements ) of slabs.

Sinclery i thing that is not good idea to divide bars from panels and to design elements from to diferent models.

If i have understood you, i think so.

Feel free to discuss i can help you.

Regards
Z.G.

[length zero]

Im curious also to know which type of buildin are u analysing.
Because my post havew ro concern with typical buildings with slabs walls and frames.

[medo]

I divide the structure model by selecting the elements that I wish to separate and click on 'Substructure save'. In this way I want to perform only design of selected elements because the designing time is reduced substainally.
I am not performing structure analysis on divided structural elements. The substructure saving should save the results from the global analysis, but in my case it does not for the panels.