ARCHICAD IFC export. Wall connection problem

[Anonymous]

Hello all. I have a problem with IFC export, and I need your help. Here is a question:
After exporting IFC some walls have incorrect connection in Solibri Model Viewer. In Model in ARCHICAD 19 everything is OK. Why after exporting with standard export properties we have connection problems of some walls corners?

[Barry Kelly]

I don't know if there is another solution to your problem but I see your wall reference lines are on the inside of the walls.
Technically a wall is only as long as its reference line so there is really no wall in the corner.
Archicad automatically fills in the gap so you see a true corner but it seems that this is not being translated in your IFC model (I don't know if there is an option to fix this in the translator maybe?).
Turn "Clean Wall & Beam Intersections" off in Archicad and you will see the same thing.

However if you move the reference lines to the outside of the walls I think you will find it will look better in the IFC model.

Barry.

[Anonymous]

Barry wrote:
Turn "Clean Wall & Beam Intersections" off in Archicad and you will see the same thing.
Barry.

Nice! Your recommendation is true. Now Walls and Beams corners have right connection in Solibri Model Viewer. Thank you!

[Laszlo Nagy]

The IFC format is based on extruded geometry and normally this is how geometries are exported as IFC. A wall is exported as a profile that is extruded along a path.

However, preservation of the exact geometry has always been an important point. This is why there are BREP definition options when exporting IFC.
If you go to the IFC Translation Setup Dialog, go to the Export Options panel and click the Conversion Options button, you will see that you can set the BREP option for various element types, like Elements participating in SEOs, Elements with junctions (like a Wall corner), Slabs with slanted edges, and IFC Site geometry.

Also, if you use the "Coordination View (surface geometry) IFC Model View Definition, everything will be saved as BREP and your exact geometry will be preserved in the exported IFC file.