Large topo site/job: Advice please

[gbrowne]

I am embarking on a very large job, (for me anyway), over 100 acres, with 5 linked files, 22 buildings in total on a sloping site. One of the buildings is repeated 18 times, and as we have previously built a couple of them, we have all the drawings and details in CAD externally. Do the Revit Jedi have any advice for me as I set the whole thing up? Although the site will be large, it won't be terribly detailed. Should it be worksetted for example? Will this assist in regen times?

Your thoughts please. Thank you in advance!

[Elmo]

Site separate and link in the buildings to the site. That would be my process, I don't even think worksets will be necessary at all.

[gbrowne]

So far thats how I have it set up! At the moment the topo is the biggest drag, everything takes a while to do unfortunately..

[sbrown]

In 2008 you can make groups, change them to links work on them and reload them. So I have a large site and you can't possibly do any grading on the site as a whole, so the solution I came up with is to create a grid over the site(I make a level called site overlay which is far above the topo) this is where I draw the site plan so it will "drape" over the topo and not get hidden by it. Anyway. with your grid created you can now split your surface along these lines, group a piece, link it, then open the file, do your grading and reload it, then at some point merge them back into one piece. There is a downside to this you will have a line around each split area until you merge and sub regions can't span over 2 pieces of topo.

so anyway. If you can work on the site as one model leave it as one, if not the method I describe will improve performance. Also use the simplify surface tool to help speed things up too.

[gbrowne]

Thanks for that interesting explanation, quite a technique/workaround you have there!

I think for the time being I will try and leave the site model as a single model, as I said before its not terribly complex and I find that once settled they rarely change a great deal.

[pfschuyler]

If you intend to do a fair amount of site grading, especially detailed site grading (as required, I am sure), do NOT use the Revit tools for this. That is my sincere recommendation after plenty of hours of hard earned frustration.

I would recommend instead that you parallel your Revit models with Autocad and/or specialized civil or site building software. When you need to grade the model, do the actual modelling in that other system, and bring that data back into Revit as needed and rebuild new topos which you can keep in various phases or in separate files. Building a topo from imported data is relatively fast and efficient, editing a topo is not. Yes, that's an awful pain, but better than the alternative.

The Revit site tools are a dangerous lure unless you are dealing with a simple site. When you start to get into grading it seems very workable, but the larger the model the less efficient you will become. You will spend 8-10 hours trying to edit a couple of basic driveway entries to be reasonably accurate...things like that. On my large site model for example, there is a 20-30 second delay every single time I add, move or delete any point. The same goes with editing pads. And that with my Athlon 64bit X2 6000+ CPU with plenty of excess ram. There is no paging to disk...Revit just does not allow you to edit the site without regenerating the entire model during every editing operation. Your productivity will be totally consumed by the site model if you are not careful to just steer clear of it.

Until Autodesk fits a fix into their expansion scheme for Revit I would highly advise against using these site tools for anything other than abstract representations of a site.

Paul Schuyler

[sbrown]

Paul is absolutely correct. I should have clarified that I'm only using the site tools to site the building and get the rough grading for sections. I wouldn't think of attempting to grad roads, etc. Thats why the site overlay level is important, its where I draft(yes draft) the site plan.

[gbrowne]

I had a feeling someone was going to advise me not to use Revit for the site information. Good advice I am sure, but I don't really have a great deal of choice, so I will have to use Revit in the most efficient, in terms of both time and processessing power.

As it happens I rough draft the roads etc in LT, then import the information in using the overlay idea at the moment.

My personal opinion is that these problems aren't going away or getting dealt with. If Autodesk wan't people to jump on board and support a platform, issues like this are going to have to be addressed. I work in an office where we are mostly, but not fully Reviting. Its issues like this that keep us away from being 100%.

[archjake]

I would agree w/ everything said here. The site tools are such a pain. I just finished a 1 acre site where I did all the grading in Revit and it was such a pain. My site had a road, multi level pads, drainage swales and retaining walls. Can I say it was a huge headache and would prefer not to have to do it in revit next time, but we only use Revit. I would recommend that you put in a service request. Its the only way we will get the attention that we need. What building does not sit on the ground? Very few!