Slab underneath imported IFC

Geometry
1

Hello all.

Ok, so I’ve got myself a real challenge here. I have an IFC file which I need to create a slab, or some kind of mass underneath it.

The IFC is all curvy and bumpy, and I need the slab to cover the whole file, but not go above it, if that made any sence. The reason being, is that I need to be able to export the created mass as an IFC, eventually create a hole/void in it, and then be able to calculate how much of that total mass the hole/void is. (For digging purposes, volume calculations).

Any idea how to solve this? I’ve tried all day with different soloutions on the internet, but I can’t really get it to work.

image.png1063×805 35 KB

Thanks in advance,

-Patrick

2

Added another picture if the question remains confusing (which is totally understandable):

image.png1063×805 40.2 KB

3

Hi Patrick.
See if my blogpost here can help you in any matter: http://jbdynamo.blogspot.no/2017/04/ammo-excavations-with-revit-and-dynamo.html

Maybe you can also post the file here and show us something of what you have already tried and not succeeded with?

4

Hi Jostein.

I’ve not saved any of the files with the things I’ve tried to work this out, but:

  • I’ve tried opening the IFC in Revit - Exporting it as a DWG - Importing the DWG and making it a topography surface.

After this, I’ve ran various scripts, with no success, and a lot of crashes.

I looked at your blog, and tried to do it with mine, but I couldn’t quite work it out. Does the surface HAVE to be a topography surface? Is there no possible way of creating a solid mass UNDER the curved/bumpy IFC? Does it require any special format ect?

I’m quite new to this, so I must appologize if I sound like a total noob.

Thanks

5

I need to be able to export whatever mass I create to IFC, doesn’t matter how deep it is, as long as the top of that mass matches the imported IFC terrain.

6

I’ll take the bait, fellow countryman and all. :slight_smile:

Here’s one way of doing it:
I’ve opened the IFC in Revit and selected the surfacemodel with Select Model Element, then this:

image.png1919×509 43.6 KB

image.png1808×557 62.5 KB

image.png1490×531 51.7 KB

Please mind that I offsetted the boundarycurve 1 cm or so inwards in order to be sure that the solid will be cut by the “topography”.
Here’s a link to the script: https://www.dropbox.com/s/gtwmuwcj86bdpxl/TopoSolid.ByIFC.dyn?dl=0

7

Ok, some progress, but still a few faults:

image.png1237×686 34.6 KB

image.png1013×805 27.9 KB

The solid creates the outer shape, but doesnt cut at the top of the IFC. Any ideas?

8

The Point.Z node will be yellow since it’s part of a function. Have you tried reversing the offset of the boundary curve? ie give it a positive value?

9

Jostein, thank you so much! It worked. I think my main problem was with how I opened the IFC in Revit.

For this to work, the IFC must be opened directly to Revit. No linking, in other words.

You are a champ dude!