Most compatible conflict checking program with ArchiCAD

[Anonymous]

I've just started some research in searching for which "conflict-checking" program or add-on would be most compatible with ArchiCAD?

I've noticed that Solibri provides a conflict checking program for the IFC models in addition to its Solibri Model Viewer. I do not know much of this at the moment, but wanted to check in and see if anyone else has done any kind of "conflict-checking" with their ArchiCAD BIM model.

Thanks!

[Anonymous]

NavisWorks files can only be exported from ArchiCAD 12 right now. AC13 will presumably be supported in NW2011 - so I expect we will have that around June or so. You can also use DWG and IFC files from ArchiCAD in Navis but DWG loses a lot of information compared to NWC and Navis' IFC import was quite poor last I checked.

Solibri works very well with ArchiCAD IFCs so it probably rates as the most compatible, especially since IFC export from AC13 seems to be significantly improved (I am just getting around to serious testing right now). The main drawback is that IFC export can be quite slow and the files quite large. On the plus side Solibri offer much that Navis does not.

Both of these programs represent a substantial commitment of time and money so you need to be sure that they will serve your needs.

Keep in mind also that it is better to do as much interference checking/clash detection as possible in ArchiCAD before sending it out. This is made more difficult due to ArchiCAD's very limited 3D import capabilities, but I still go to the trouble since it is so much easier than going back and forth between the different programs. I believe the MEP add on has clash detection capabilities but I haven't had time to check this out yet. I suspect it may only be useful with models from AutoCAD MEP which would be quite limiting if true.

[Laszlo Nagy]

Matthew wrote:
I believe the MEP add on has clash detection capabilities but I haven't had time to check this out yet. I suspect it may only be useful with models from AutoCAD MEP which would be quite limiting if true.

Yes, the MEP Modeler has Clash Detection. It creates Mark-UP entries of the Clashes it has found so you can visually check where MEP stuff intersects itself or other structures.
The new Collaboration ITG Part 2 has a Section in it which demonstrates its use.

[Anonymous]

Since this clash detection has been incorporated into MEP Modeler, does that by any chance pave way for future possibility of having that built-in in the next AC release? (AC14) Although, I can imagine it being complicated to program (how will it know the difference between intersecting walls or beams by design or error?) it may not make sense to come with ArchiCAD.

Would be a nice feature since some BIM project submittals have guidelines that include running conflict-checking programs or application through the BIM model.

Anyway, I will have to check out that Collaboration ITG Part 2. Thanks for your comments, Laszlo and Matthew.

[Anonymous]

Detecting the clashes would be, I suspect, a rather trivial issue. All it has to do is search for overlapping elements. Since ArchiCAD can already automatically detect and resolve beam intersections with slabs it would seem that most of the code for this is already written. Remember that intersecting walls don't overlap. Their geometry is trimmed to fit by ArchiCAD.

A little more difficult would be constraining the clash detection. It is generally useless to just clash everything with everything. In Navis this typically generates thousands of meaningless results. For example, expansion anchors that are modeled with the MEP hangers but not subtracted from the structural decks will all show up as clashes. In ArchiCAD this could probably be done rather easily by leveraging the layers and selection tools and just running the clashes between specified layers on the current selection.

I think the biggest chore in developing this function would be making the UI. Specifying how the various users might want to interact with this function and then putting it together with well designed tools and dialogs is quite a job.

Of course, as I think I've said before, I have been making a large part of my income doing this sort of stuff over the last couple years and I find I rarely use the clash detection tools. Visual inspection is usually more effective and this works in ArchiCAD right now (obviously).

The biggest obstacle to meaningful clash detection in ArchiCAD is the inability to link the external geometry from Revit, CADmep, and so on. This seems to be improving with IFC import but DWG is tedious and error prone and can only be done as library parts (making automatic clash detection impossible).

[Anonymous]

Also, ArchiCAD being a modeling software, it taxes the system much more than non modeling ones, like Solibri, VICO, or AtLantis.

I suspect it will always be faster to check this kind of stuff on a non modeling software, as it is always faster to render in a non modeling software.

[Anonymous]

Krippahl wrote:
Also, ArchiCAD being a modeling software, it taxes the system much more than non modeling ones, like Solibri, VICO, or AtLantis.

I suspect it will always be faster to check this kind of stuff on a non modeling software, as it is always faster to render in a non modeling software.

I'm not so sure about this.

If you are speaking just of the automatic clash detection rules you are probably right, but because of procedural rather than a structural difference between the Model Builders and the Model Checkers. Since this is a core function of the Checkers it will be a priority for development whereas it would always be a secondary function in the Modelers. I see no reason in principle that efficient clash detect couldn't be built into ArchiCAD or Revit if the programming resources were dedicated to it. The parallel to rendering is quite apt.

On the other hand, I find using a dedicated program for clash detection can be quite tedious methodologically. Since any corrections have to be made in the modeling software going back and forth between the two can be quite onerous. This is why I often import the mechanical models (at least the ductwork) into ArchiCAD to eliminate most of the clashes before the model is exported to Navis or Solibri.

[Anonymous]

I am not saying that clash detection can not be done inside a modeler, only that it will probably be faster on a checker/viewer, because there are less things going on (like renderings).

I agree that, for now, checking stuff manually is less error prone and produces less redundant information, but my guess is that this happens because checkers are on their infancy.

Your experience (like mine) stems from being a one man show, and then it is easy to verify as you model.

From a complex model team structure point of view, where you have someone doing architecture, another structure, another H VAC, and so on, having a team leader who verifies everything outside a modeler makes sense. This way you can keep each role independent, with much better quality control.

[Anonymous]

Krippahl wrote:
From a complex model team structure point of view, where you have someone doing architecture, another structure, another H VAC, and so on, having a team leader who verifies everything outside a modeler makes sense. This way you can keep each role independent, with much better quality control.

I think we are pretty much on the same page with all of this. There are two distinct aspects to clash detection/coordination. One is trying to get the model right in the first place by linking other trades into the authoring programs. The other is checking all the results together independently in the checkers. This is the most thorough and effective approach and probably always will be.

[Anonymous]

Matthew wrote:
Solibri works very well with ArchiCAD IFCs so it probably rates as the most compatible, especially since IFC export from AC13 seems to be significantly improved (I am just getting around to serious testing right now). The main drawback is that IFC export can be quite slow and the files quite large. On the plus side Solibri offer much that Navis does not.

Solibri provides also a direct link between ArchiCAD and Solibri Model Checker as an ArchiCAD plugin. The user can send model to Solibri without exporting an IFC file. It is faster than ArchiCAD IFC export and the user can also transfer selections between Solibri and ArchiCAD. AC11/12/13 for Windows and Mac is supported in the latest plugin release.