buildingSMART Forums

Does these attributes are defined by buildingSMART or not?

common-schema
ifc2x3
#1

Good evening everyone.
i was working on IFC export , and faced certain new issue in finding some data in IFC files.
ISSUE1: which Attribute/Entitie store the clear cover or side cover etc. Means covers provided during reinforcement of members like column, beam, slab etc.
ISSUE1: The spacing between the rebars i.e if we provide 10 dia @100c/c where this 100 will store in IFC,
Some software transfer then in proxy or ifcpropertysinglevalue but it is not extracted or connected to any members so impossible to use them.

Major issue : We give material to Structure members as M 20, M25 etc for concrete and Fe500 for Rebars
But again nothing is exported to IFC . we get concrete as label in IFCMATERIAL and again some software give M25 in proxy.
we have attritube like IfcMechanicalMaterialProperties , IfcMechanicalConcreteMaterialProperties etc Why software’s are not using these to store the properties of materials.
Thank you.

#2

Good morning @Tandeep - do you mind attaching an IFC file that you have exported as an example, and also clarifying BIM authoring tool you are using to model your building?

#3

Good Evening
I am sending you a slab (ifc) which is having reinforcement in it.
This file is model in FreeCAD.
I also tried in revit and tekla, results were same.
123.ifc (602.4 KB)

#4

Anyone here having any knowledge about this.
Please help.

#5

AFAIK, it’s not IFC that is to blame, but most viewers don’t show you material information, apart from their name. I know for a fact that I can export the full information about the material from ARCHICAD into IFC, especially now for IFC4, and I can confirm that the IFC file contains this information. But there is no way I can see these properties in e.g. Solibri or BIMcollab Zoom, alas.

1 Like
#6

I am not blaming IFC.
Its software which are not doing there work.
buildingsmart must take strict action against them because they are causing too much problems during export/import.
I had also used the ARCHICAD but nothing good found in IFC about materiel, just i got is name nothing else.
Can you share me a small file where material and all its properties are exported by ARCHICAD in IFC

But if we talk about spacing of rebars, i had not found any entity/attributes in IFC schema which store spacing between 2 or more bars.

#7

Here is a fragment of Material Properties as exported from ARCHICAD into IFC4, with the translator set to export Material Properties

#228= IFCMATERIAL('Reinforced Concrete - Structural',$,$);
#235= IFCMATERIALPROPERTIES('Pset_MaterialThermal',$,(#239,#246),#228);
#239= IFCPROPERTYSINGLEVALUE('ThermalConductivity',$,IFCTHERMALCONDUCTIVITYMEASURE(2.5),$);
#246= IFCPROPERTYSINGLEVALUE('SpecificHeatCapacity',$,IFCSPECIFICHEATCAPACITYMEASURE(1000.),$);
#247= IFCMATERIALPROPERTIES('Pset_MaterialCommon',$,(#249),#228);
#249= IFCPROPERTYSINGLEVALUE('MassDensity',$,IFCMASSDENSITYMEASURE(2400.),$);
#250= IFCMATERIALPROPERTIES('AC_Pset_MaterialCustom',$,(#252,#253,#254,#255,#256,#257,#258,#259,#260),#228);
#252= IFCPROPERTYSINGLEVALUE('Embodied Energy',$,IFCTEXT('2.33 (MJ/kg)'),$);
#253= IFCPROPERTYSINGLEVALUE('Embodied Carbon',$,IFCTEXT('0.242 (kgCO\X2\2082\X0\/kg)'),$);
#254= IFCPROPERTYSINGLEVALUE('ID',$,IFCTEXT('ST-06'),$);
#255= IFCPROPERTYSINGLEVALUE('Description',$,IFCTEXT('Description'),$);
#256= IFCPROPERTYSINGLEVALUE('Manufacturer',$,IFCTEXT('Manufacturer'),$);
#257= IFCPROPERTYSINGLEVALUE('Participates in Collision Detection',$,IFCBOOLEAN(.T.),$);
#258= IFCPROPERTYSINGLEVALUE('Name',$,IFCLABEL('My Name'),$);
#259= IFCPROPERTYSINGLEVALUE('Category',$,IFCLABEL('My Category'),$);
#260= IFCPROPERTYSINGLEVALUE('Description',$,IFCLABEL('My Description'),$);

AC23_concretemorph_IFC4Materials.ifc (8.7 KB)

#8

And here is a fragment in IFC2x3… Properties are there in the IFC export.

#236= IFCMATERIAL('Reinforced Concrete - Structural');
#239= IFCSTYLEDITEM($,(#191),$);
#241= IFCSTYLEDREPRESENTATION(#136,$,$,(#239));
#243= IFCMATERIALDEFINITIONREPRESENTATION($,$,(#241),#236);
#247= IFCRELASSOCIATESMATERIAL('1prswmCKtd8CDhgsEfCIVS',#12,$,$,(#217),#236);
#250= IFCPROPERTYSINGLEVALUE('Renovation Status',$,IFCLABEL('New'),$);
#254= IFCPROPERTYSET('20n$Y4ocGFyd$cEFhrKhFB',#12,'AC_Pset_RenovationAndPhasing',$,(#250));
#259= IFCRELDEFINESBYPROPERTIES('1bWoYR_9S5uFHcyLAgC1MI',#12,$,$,(#217),#254);
#263= IFCPROPERTYSINGLEVALUE('ThermalConductivity',$,IFCTHERMALCONDUCTIVITYMEASURE(2.5),$);
#264= IFCPROPERTYSINGLEVALUE('SpecificHeatCapacity',$,IFCSPECIFICHEATCAPACITYMEASURE(1000.),$);
#265= IFCPROPERTYSINGLEVALUE('MassDensity',$,IFCMASSDENSITYMEASURE(2400.),$);
#266= IFCPROPERTYSINGLEVALUE('Embodied Energy',$,IFCTEXT('2.33 (MJ/kg)'),$);
#267= IFCPROPERTYSINGLEVALUE('Embodied Carbon',$,IFCTEXT('0.242 (kgCO\X2\2082\X0\/kg)'),$);
#268= IFCPROPERTYSINGLEVALUE('Name',$,IFCTEXT('Reinforced Concrete - Structural'),$);
#269= IFCPROPERTYSINGLEVALUE('ID',$,IFCTEXT('ST-06'),$);
#270= IFCPROPERTYSINGLEVALUE('Description',$,IFCTEXT('Description'),$);
#271= IFCPROPERTYSINGLEVALUE('Manufacturer',$,IFCTEXT('Manufacturer'),$);
#272= IFCPROPERTYSINGLEVALUE('Participates in Collision Detection',$,IFCBOOLEAN(.T.),$);
#273= IFCPROPERTYSINGLEVALUE('Name',$,IFCLABEL('My Name'),$);
#274= IFCPROPERTYSINGLEVALUE('Category',$,IFCLABEL('My Category'),$);
#275= IFCPROPERTYSINGLEVALUE('Description',$,IFCLABEL('My Description'),$);

AC23_concretemorph_IFC2x3Materials.ifcxml (38.1 KB)

#9

Firstly your IFC is Zero , it not having having any member to whom material was assigned.

The values which are in IFCPROPERTYSINGLEVALUE are only for this ifc file and software we imported from.
It will not import in any other software and not viewed in viewers.
building smart have a particular entity for material properties but they are not used by any software’s.
as i already told

we have attritube like IfcMechanicalMaterialProperties , IfcMechanicalConcreteMaterialProperties etc

why they are not used by software or ARCHICAD you are talking about.

#10

Hi @tandeep, sorry for the late reply. I see you are using FreeCAD. I can help you with this, but I will need more information, but this forum is not the right place for detailed individual vendor support.

Can you please post here: https://forum.freecadweb.org/viewforum.php?f=39

Please include:

  1. A copy of your FreeCAD file that we can use to replicate the issue
  2. Which version of FreeCAD you are using
  3. Attach the IFC you have exported from it
  4. Explain the issue again on that forum post for completeness.

Please also send me an email (I have messaged you my email address) with the thread link, and I will help you debug your issue and make sure that FreeCAD authors the IFC file as expected.

#11

Hi @Moult
I am not just talking about FreeCAD.
I had examined this in Revit, ArchiCAD, FreeCAD, AecoSIM, etc , basically i checked these on main BIM softwares but no one is providing me that information.
If we talk about spacing between the 2 bars, i checked and find no ifc attribute which can store spacing between 2 bars.
For Materials properties we have attributes but no software is using that attributes, so why building smart is not taking any action on them.

Well i am also there on FreeCAD forum and will discuss there also.