Importing 3D Topograhy Into Revit

[kim.74445]

I have a student in one of my classes who is unable to import his 3D topography (which included mass buildings, hard surfaces and topo) into Revit. He has the information in both an AutoCAD file and a SketchUp file and has purged everything out that is not needed. Every time he goes to import the file his computer freezes up and he is not able to get the geometry into Revit. It would be very time consuming for him to redo everything in Revit. Is there a better way he should be importing the 3D topo file (for example, creating a family of it first and then loading the family)? Can anyone help with this dilemma?

Thanks!

[sbrown]

Typically 3d topo would be created directly in revit using the topography tools or an imported dwg file containing contour lines at the appropriate z elevation. My guess is the dwg is just too big or complicated for revit to import. Try wblocking it into sep. pieces. and bringing in sep chunks.

[cliff collins]

Autocad 3D: Purge the file 1st. Delete any unneeded info. Only import the 3D topo as a separate file. Revit should be able to do this very well, even with large sites. Watch out for Origins in the Autocad file which are extremely far away from the site--Revit has limits of about 2 miles (?) for remote origins. BTW, Revit's "origin" is right in the middle of the default template's elevation tags in a plan view. Make sure to export from Autocad from a 3D view!!

If using Sketchup--you must import into a new Mass family 1st, then load into Revit project. I do not recommend it, but it can be done. Mass must be turned on in any view you want to see the topo in.

I would suggest using the 3D polylines from the Cad file to import, and then convert to a toposurface in Revit, as another approach.

Good luck!!

[saeborne]

Autocad 3D: Purge the file 1st. Delete any unneeded info. Only import the 3D topo as a separate file. Revit should be able to do this very well, even with large sites. Watch out for Origins in the Autocad file which are extremely far away from the site--Revit has limits of about 2 miles (?) for remote origins. BTW, Revit's "origin" is right in the middle of the default template's elevation tags in a plan view. Make sure to export from Autocad from a 3D view!!

One more thing about importing a DWG file as a basis for topography... For some reason, you can't import the DWG file as a "Link." Don't know why, but Revit won't generate the topo from a linked revit file. Instead, you have to import with link unchecked.

Hope this helps.

Bryan

[kim.74445]

Thank you all so much for the info. I will pass it along to the student and hopefully he will able to now import his file.

Thanks!!!

[patricks]

One more thing about importing a DWG file as a basis for topography... For some reason, you can't import the DWG file as a "Link." Don't know why, but Revit won't generate the topo from a linked revit file. Instead, you have to import with link unchecked.

Hope this helps.

Bryan

Of course it will work with linked files. I pretty much always generate topo from linked CAD files, as I never do a straight import of a CAD file because of possible performance issues.

[kim.74445]

Ok, the student has tried everything suggested and still cannot get the topo to load into Revit. There is too much work to just recreate it. The CAD file with the topo is 18MB and the SketchUp file with the same topo is 19MB. Does anyone have any other suggestions or do you know if it is possible to upload the files to a Revit Tech for them to explore a possible problem? If we expect the students to use Revit, it needs to work with the project requirements we have set forth...we can't keep running into snags!!!

Also, I was able to use the Create Mass tool and import the SketchUp model into a new mass, but then when I went to finish the mass I got this error message: "This family instance has too many edges and faces. Remove unnecessary geometry or split the instance into multiple instances." I cannot explode it because everything gets deleted except for a few lines. HELP!!!

Thanks so much!!!