How Big can you go?

[david_peterson]

I have a new project that we will be starting in a few weeks and I'm wondering what's the best way to go about it.
the main building footprint is roughly 1500'x550' with a total sqft of "usable" space in the area of 1.6million sqft.
I'm wondering if anyone has some advice as to how to split something like that up or if Revit can even handle a footprint that big. Not to mention the site which is something like 1 mile by 3 miles.
Specifically I'm wondering how well the model will interact when it comes to joining footings and wall. I have a hard enough time getting revit to model my concrete structures they way they should vs the way revit wants to do them.
I know that I may want to split up the building based on expansion joint locations, but I'm not sure how much help that's going to get me.
There's going to be plenty of things that will complicate this process including construction phasing and package phasing (these may not be the same)
All I know is that this project is going to be run at light speed since someone thinks they can get a foundation package by the end of Oct. (We haven't even picked a site yet)
I'm looking for for input on the structural side.
If anyone has any good ideas or thoughts, they would be much appreciated.
Thanks in advance.

[damon.sidel]

How big have you gone before and at what point have you had problems that would lead you to suspect this will be a problem? To what level of detail are you going to get?

I don't have experience with a project in Revit of that size... the largest I've worked on is about 700,000 sf, but we put A LOT of detail into it with. The file size is about 480MB and it includes high-res images, lots and lots of ACAD for coordination, and some serious modeled detail. It can get slow dealing with certain issues, but in general works very well.

I'm curious to know what other people have to say because we have a potential project that is on a similar scale to yours that we might do in Revit... the office's reservation is that training staff, not the program itself.

[david_peterson]

We are shooting for somewhere between level 200 and 300.
I don't think I'll be modeling rebar, but I would be modeling gusset plates, concrete reveals, curbs, braces, outriggers... and other misc steel, base plates, anchor rods, foundations, footings, columns, beams.... slabs, slab edges, bent plates, pits, sloped slabs, trenches......basically everything but rebar, bolts and connection plates and angles.

On the upside, they've ordered us new workstations with i7 chips and SSD drives, so..... that should help.
How much ram were you using on the 480mb model. I really don't think I'd get up to that kind of file size in a structural model, but you never know.

I did talk to a few other people around our office and was told that splitting into multiple models isn't a good idea for many reasons. Just think about changing a title block or having to update a family or shared parameters....now instead of one place you'll have many. That was just one reason.

Any additional info would be a great help

[damon.sidel]

We are using i7 960 @ 3.2GHz processors with 12.0GB RAM on Windows 7. Our graphics cards are terrible, so I assume some of our slowness (navigation related) could be improved with better cards.

I agree with your colleagues that splitting it up would be quite problematic. Unless there was a natural split, like multiple "buildings" connected only by walkways/bridges or something.

[david_peterson]

Well if you were able to get that to work with only 12gb of ram I should be OK assuming Revit doesn't stat getting those error with the "Point is to far from origin" kind of things.

Expansion joints along the MFL walls would be the point to separate them. But I really don't want to have to do that. Besides along the expansion joints I'll have double rows of columns, but they'll be on combined footings.

Since I would need to link them all together in order to create the documents, I'm thinking I'm going to try to keep it all in one model until it breaks or becomes super unstable and then split it up at that point.

[damon.sidel]

Yeah, maybe that "too far from origin" stuff. But I bet it won't get unstable so much as just slow. Let me know how it goes.