I didn't know you're doing stress analysis on your frameworks. I don't have stress analysis in my Inventor. I've never used it over the years, and did all my calcs by hand. But we always had a PE check our calcs and sign-off on them for the state/county/city, etc. So I can't offer any suggestions on that piece of your project.
Your video card looks like it's a monster, so it should work well. I've run AMD processors in my internet computers over he years, but they don't do so well w/Inventor and other CAD heavy weights. I'm not saying your 4.8ghz processor isn't up to the task. But it may not be as powerful as an Intel i7 or better. When I used an equivalent AMD w/Inventor I noticed it was 1/2 to 2/3 the speed of an Intel. Anyway, I assume you're not going to change computers any time soon.
For a STRUCTURAL STEEL project there's a few different ways I would approach it, depending on the level of detail you need.
If you're going to go from analysis to fabrication drawings, and if you do these STRUCTURES frequently, then Inventor is DEFINITELY NOT the software you want to use. Instead, depending on the size and complexity of your structures, you are going to want to use one of the STRUCTURAL STEEL programs, such as ParaBuild, AdvanceSteel, Tekla (in ascending order of price-point) or any of the other contenders. Only thing is, they're quite pricey. If you've never used any of them before now, you can download and trial a student version of Tekla for free. It's pretty easy to model in, but doing drawings and the other stuff is a real PITA (steep leraning curve). I did a trial on ParaBuild up to intermediate level skill, and it was a bit better, but didn't have the full functionality that Tekla does. I don't know about AS or any of the others. Tekla has this amazing concrete/rebar module that beats everything I've seen! In any case, 'you have to pay to play'. You'll know what I mean when you see the prices. If I did a lot of STRUCTURAL jobs, I would get Parabuild for the level that I 'play' at.
Assuming you're not interested in STRUCTURAL programs, this is how I would approach your project:
1. The first thing to note is, Inventor SUCKS at STRUCTURAL work, primarily b/c of 3 factors:
a) It has no CONNECTIONS
b) It can't make AUTOMATIC DRAWINGS (esp. BEAM/COLUMN weldments & DETAIL drawings)
c) It can't make BOMS like it needs to, and customizing it to do so is a LOT of work
(Example: One project I did in Inventor had 70 D-sized sheets of drawings. It was UNBEARABLE doing it in Inventor compared to if I had a STRUCTURAL STEEL program!)
2. there are 3 basic ways I found to approach this kind of work:
a) One gigantic FG (FrameGenerator) assembly with all details inside it that you break apart at the very end when you're all finished using the DEMOTE command to create individual assemblies of all the weldments or assemblies that the GA (general arrangement/top-level) assembly contains.
b) A structured FG assembly containing weldments and assemblies that you make on an individual basis and place into the GA assembly
c) A structured NON-FG assembly like 'b)' above.
I prefer a combination of b) & c) above. There's a LONG thread in this forum on 'a)' above, but I can't find it to link you to it, sorry. But you have to invest an unbelievable amount of time into a LIBRARY of CONNECTIONS and PARTS to do it that way.
In your case, since you're using Inventor to do calcs, you may want one model to do calcs, and then make another model for detailing/fabrication. That way you can keep your FEA model SIMPLE and then dress-out your DETAILING model to the last nut and bolt. The level of detail in your DETAILING model will KILL your FEA processing overhead.
Any way you do this kind of STRUCTURAL project will be a drain on your computer resources. But I found if you structure the GA properly, you will cut way down on the computing overhead. For example:
1. You can make one GA 'master sketch' for the entire structure (like you did), but don't use any 3D Sketches (like @gcoombridge says), b/c they really KILL processor power). Also, don't use any Surfaces for the same reason. Use as few Work features as possible, and keep all 2D sketches a simple as possible.
2. Identify all your individual WELDMENTS and ASSEMBLIES (e.g., stairs, railings, x-braces, beams, columns, etc.) and Derive your GA ipt file into an iam file and make each weldment/assembly as a stand-alone part in the GA, then Ground it in your GA assembly when finished.
3. Combine all weldments and assemblies that belong together into a single assembly so you cut down on the number of assemblies in your GA assembly. Example: stairs + l.h. railing + r.h. railing + supports = one STAIRS assembly. That's 4 assemblies reduced down to 1 assembly. That means you have only 1 assembly instead of 4 in your GA Assembly.
4. The idea behind '3.' is to think about this in terms of PHASES of construction and/or FABRICATION. You're setting your model up for easier drawing production for the shop, and for CONSTRUCTION phases. You can segment out your project for easier building and construction.
5. Make one beam and column assembly for all duplicates, and copy them and constrain them where they belong in the GA assembly. Some of them you may be able to use assembly Arrays. That cuts WAY down on computing overhead.
6. Connections are tricky. You can combine welded clips/knife_plates/etc. w/the beams or braces into an assembly, as well as combining bolted clips/knife_plates/etc. w/the beams or braces into an assembly/weldment, b/c that's how you detail them. Or, you can do it the hard way and put ALL loose clips (etc.) into the GA assembly and use ViewReps to represent the assembly (this may not work in 2020 and newer, I don't know b/c I don't use it). I use ViewReps as a LAST RESORT b/c of the down-stream headaches when making drawings.
7. Add all fasteners to a separate assembly, or add all fasteners to the GA assembly. But make sure you can turn them off in your GA assembly, due to the computing overhead they cause. Same w/all small details, esp. the ones that are hidden (like clips).
That's a general overview of how I would approach your project. It's possible the reason you have such bad overhead is that you're doing FEA inside Inventor, and the computing overhead is kicking your butt. In that case, you may want to try to close the program and reopen it. If that doesn't help, I would try closing the program and shutting down the computer, then restarting and reopening Inventor. That way you can DUMP the memory and SEVER all processing threads. If someone else in here can open your assembly, they'd be able to tell you what level of overhead it has, so you'll get an idea of how much drag it puts on your their system in comparison.
There's much more to be said on this subject, but I'll leave it at that for now. I have many years of ANGST against Autodesk for NEGLECTING the STRUCTURAL DETAILING aspect of Inventor. Like I said, if I had a steady flow of structural work, I'd use ParaBuild to do it. But from what I've seen in ParaBuild and Tekla, they are not very good at MISCELLANEOUS structural work. By 'MISCELLANEOUS structural work' I mean custom stairs, railings, awnings, and things like that. And I certainly wouldn't use them for ARCHITECTURAL miscellaneous structural work!
Hope this helps...
... Chris
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