I have a large structural steel and concrete model that was modeled in AutoCAD 2010 as solids.  It's been years since I last used AutoCAD but this does not seem like the appropriate platform for such a large solid project.  My system is more than adequate for AutoCAD but the geometry is so bulky that I can't do anything with it.  Any suggestions?  Is there a way to make my geometry more manageable within AutoCAD or should I move it to another application?  I have Revit but from what I've read, it does not seem feasible to move the geometry to Revit.

Hello bfackrell, if you want to work with big 3D files and your computer is slow you will have to use :
BLOCKS on each component with adequate names to manage them with their aflabetic numbering.
PURGE, SCALELISTDELALL.
If all this doesn't work you will have to go to XREF like with Solidworks for example that's to say drawing each component in different files and be very carefull with the names and places of each files and directory not to move rename, etc...
If you go to XREF each time you will insert a component in your "assembly" file you will get more and more layers with a complex name ( don't know if this can be "cuted off" ).
Tell us if this helped or not, your tests and results.philippe JOSEPH2014-11-05 07:55:03

What kind of file size are you dealing with?What are the full specs of your computer?My initial suggestion would be twofold.First.  Use Overkill, -Purge (Regapps first; All second) and Audit on the drawing.  Twice.  Then save.  Does the file size reduce at all?Second.  Make use of Xrefs.

Thanks for the tips.  I purged, with no change.  Then I did a bind of the XREF's (still slow) then opened it in Microstation did some things and re-opened in AutoCAD and it works great!  Not sure what Microstation did but it fixed the problem.

I'd be very careful going back and forth between Microstation and
AutoCAD primarily because when you import a Microstation drawing into
AutoCAD the linetypes will cause the file size to balloon out of
control.  It is such a bad problem that AutoDesk released a hotfix that
deletes the linetypes so as to reduce the file size.