IFC export File Dimension

Jacopo

We work with BricsCAD BIM, mainly with 3D solids objets. We have a problem of file dimensions: we need to not exceed 250 MB by contract. This starts to be really challanging since our models are growing and gaining detail along the project. We even try to use some specific IFC compressors but the result is somenthing around 90-95% of the original dimenstion, that is not resolutive.

We work already with splitted model. (one model for piping, one for structures, one for equipements, one for instrumentations etc etc). Further model division could be a problem.
On "settings-->BIM-->Import and Export-->IFC-->Level of tassellation" we already set the option to LOW. But that is not sufficient anymore.

We did several export trial to understand what is the critical factor that makes file dimensions grow. We didn't find any particular dependence on number of surfaces, numbers of nots or number of solids. It looks like everythink contibute to file dimenstion grow.

On the other hand we have collegue that works with Tekla and Revit: a "same level of complexity" ifc model have a much much smaller dimension.

Does anyone know:
1) Which are the best settings in BricsCAD BIM in terms of file dimension export? Any suggestions?
2) What are the critical factors in 3D modelling in BricsCAD BIM that makes the dimensions grow?
3) Why other software have best performance in terms of file dimension export?
4) Any other miracle?

Many Many Thanks!
Jacopo

Hans Lammerts

What i could think of is IFC4 in stead of IFC2x3. Geometry wise this has major advantages. Maybe blockify has a positive effect. Split up the model at levels of parts. But a 250 mb limit is a strange demand to begin with. Why?

Jacopo

Yeah, it is a client demand to limit file dimension for management reasons. We have also to share and exchange a lot these files so it is reasonable that they are limited to a proper size. At the beginning was even 200 Mb.

Tiemen

Hello Jacopo,

There are different reasons why the file size could grow: indeed, complex geometry is one possible answer, but it could also be related to property sets and properties (which you might not always need). Please feel free to send us a few examples so we can further investigate where the size is coming from. You can submit a support request here: https://www.bricsys.com/protected/support/NewSupportRequest.do?categoryID=115

Michael Mayer

@Tiemen said:
Hello Jacopo,

There are different reasons why the file size could grow: indeed, complex geometry is one possible answer, but it could also be related to property sets and properties (which you might not always need).

Hmmh,
that sounds like an interesting item for a Brickscad Blog entry ....

You are not talking about basic properties like Layer and Material assignments
but things like BIM Tags and information that we can also see and access by
Property Palette ?
And those can seriously grow file size ?

At first I thought of "Attributes".
I don't really need or want them but get these from other Apps DWG exports,
which pack in all kind of former BIM Information.

Jacopo

Thanks @Tiemen i am going to open a ticket with Chiara Rinaldi Profile.
In this period we "kind of" understood that curved surfaces has a much higher impact than flat surfaces. That is obvious but our BricsCAD provider told us that Flat/Curve factor have much higher impact than in a normal dwg file because of the mech method of IFC export. (That sound realistic?)

@Michael Mayer
We have huge list of custom properties sets, liked to each BIM object (kind of 80 field per object) , but at the moment any of these is filled so they have no impact on file size. We did some trials (full/empty property) and we determined that all full could impact something about 5-10% of total file size. In any case I will keep you updated when we will massively insert information in the model.

Michael Mayer

OK,
5-10% sounds reasonable.

At first when I read this I thought about 2-5 times or so ....