Convert IFC objects into native Tekla Structures objects
You can convert most linear IFC reference objects such as beams, columns, braces, plates, slabs, footings and walls into native Tekla Structures objects. Conversion also supports polybeams that have curved sections, and have originally been exported from Tekla Structures, and string, int and double type UDAs. The purpose of converting IFC objects in Tekla Structures is to help in the creation of the structural model and to avoid rework in an early modeling phase.
In IFC object conversion, IFC objects are converted either as items or as extrusions. Conversion as item means that an IFC object is converted as a Tekla Structures item, where the 3D shape defines the geometry of the item. Conversion as extrusion means that an IFC object is converted as a part (column, beam, plate, etc.) that has a profile extruded to create the length of the part.
In IFC object conversion you need to do the following:
- Before converting, check that the profiles and units in the IFC reference model are compatible with your environment.
- Check the object conversion settings in the IFC object conversion settings dialog box and change them, if needed.
- Convert the IFC objects to native
Tekla Structures objects. There are two alternative ways available in object conversion:
- Converting all selected reference model objects at one go using the Convert IFC objects command on the Manage tab.
- Converting using the IFC object conversion change management. You can also perform an update conversion with a new reference model revision using the change management.
For more information about the profile conversion logic, see section "Profile conversion logic" below. Limitations are listed in section "Limitations in IFC object conversion" below.
Is object conversion always necessary?
In Tekla Structures, reference model objects can be used in a way similar to the native objects, for example, in clash detection, reporting and scheduling. There is no need to have everything as native, because the reference model objects can also be used in many ways. For example, reference model objects can be shown in drawings and they can be listed in reports.
The reference files have the benefit compared to the copied files that the content of the files is automatically updated by the designer of that design discipline.
Check and change the IFC object conversion settings
Before you start converting, check the conversion settings and change them if necessary.
Convert selected IFC objects at one go
You can convert all imported IFC objects at one go using the current object conversion settings. You need to have at least two or more revisions of the same model.
Convert IFC objects using conversion change management - first conversion
Object conversion change management provides change detection and change management on object level. Conversion change management is needed in the initial data change management to reduce the challenges in construction projects. Objects are not converted automatically but you need to convert the objects using the conversion changes list.
Convert IFC objects using conversion change management - update conversion
If a previously converted reference object has changed in a newer reference model revision, you can compare the older and newer revisions of the reference model and update the conversion.
Macro for selecting converted IFC objects
The Select Converted Objects BasedOn Ifc Objects Selection macro selects the objects that have been converted to native Tekla Structures objects. You may want to select the converted objects to check the properties of the native Tekla Structures objects, for example. This macro is located in the Applications section of the Applications & components catalog.
Class values
The status of the converted object is reported in the changes list in the Class column. Sometimes the input data in the IFC model is not adequate to successfully create the converted object. The following table explains what the class values mean.
Class value | IFC object data | Converted object description |
---|---|---|
990 |
Parametric profile with a name |
There is enough information in the IFC model to convert the object successfully. |
991 |
Parametric profile without a name |
Tekla Structures determines the name of the object based on the objects profile. |
992 |
Arbitrary profile with a name |
The profile of the converted object may be incorrectly rotated because there is no parametrized profile data in the IFC model. |
993 |
Arbitrary profile without a name |
The profile of the converted object may be incorrectly rotated because there is no parametrized profile data in the IFC model. The profile name is set to
|
994 |
B-rep piece with a name |
The profile may be an extrema box due to the lack of profile data in the IFC model. |
995 |
B-rep piece without a name |
The profile may be an extrema box due to the lack of profile data in the IFC model. The profile name is set to
|
996 |
B-rep piece |
The object is converted using the Convert B-rep object option in converter settings. The converted B-rep object is either an item or a concrete item and is added to the shape catalog. |
Example: Convert IFC objects into Tekla Structures objects at one go
In this example, an IFC model is used as a basis for your structural model. The beams and columns are converted into native Tekla Structures objects.
Below is an image of converted beams and columns.
Profile conversion logic in IFC object conversion
You can map an IFC part profile name with a Tekla Structures profile. If a profile is not mapped, Tekla Structures uses a certain logic in converting profiles in the IFC object conversion.
When a parametric profile is used in the IFC model, the I, L, U, C, T, Z, Rectangle and Circular type profiles can be defined parametrically:
- If the IFC file has been created with Tekla Structures, the original profile name is used.
- If a profile with the same name is found from the the profile catalog, that profile will be used.
- Otherwise, Tekla Structures checks the parameter values to find a corresponding profile. If found, that will be used.
- Otherwise, a default parametric profile is used.
When an arbitrary profile used in the IFC model, the profile shape is defined with polygon:
- If the IFC file has been created with Tekla Structures, the original profile name is used.
- If the shape is detected and found from Tekla Structures profile catalog, that profile will be used. The shape detection supports the standard types of hot rolled profiles.
- Otherwise, a new profile is created based on the description of the arbitrary profile.
When B-rep geometry used in the IFC model, the object is defined with surfaces, and profile geometry information is not available:
- If corresponding item exists in Tekla Structures model, it will be used.
- Otherwise, a new item will be created and used.
If Conversion as item is used for extrusion type of part, a new item is always created.
Limitations in IFC object conversion
Tekla Structures converts most linear IFC objects to native Tekla Structures objects. However, there are some limitations in the conversion.
Tekla Structures is dependent on the quality of the IFC model, because it uses information available in the model when converting objects.
The following limitations exist in the IFC object conversion:
- The IFC4.0, IFC4.1, and any newer IFC4 formats are not supported in the IFC object conversion.
- If the IFC model does not comply with the IFC standard, it might not be converted as expected.
- Bolts, reinforcement and welds cannot be converted to native Tekla Structures objects.
- The following physical elements are currently supported: IfcBeam, ifcColumn, ifcMember, ifcPile, ifcFooting, ifcPlate, ifcDiscreteAccessory, ifcSlab, ifcWall, ifcWallStandardCase, ifcRailing and ifcBuildingElementPart.
- Only SweptSolid, Brep, CSG and Clipping representations are supported.
- Multiple representations for one object are not supported.
- Profile offset is not supported.
- Sometimes, chamfers may be converted incorrectly.