IFC 4.3.1.0 (IFC4X3_ADD1)

4.4.1.2 Element Decomposition

Provision of an aggregation structure where the element, representing the composite, is decomposed into parts represented by other elements.

The composite then provides, if such concepts are in scope of the Model View Definition, exclusively the following:

  • Product Placement — the common object coordinate system to which the parts are placed relative

By default the following constraints apply to an element being decomposed by Element Decomposition:

  • Body Geometry — composite is constructed from the sum of the Body Geometry of the parts;
  • the composite shall not have an own Body Geometry, body geometry is provided at the parts;
  • the composite shall not have an own Material assignment, material is assigned to the parts.

The following diagram shows the generic classes and relationships used when applying this concept. In addition, concepts may have particular importance to common or standardised industry practices and scenarios. For these specific usage scenarios, the tables below shows a recommended list of general usage patterns that users may adopt.

G IfcElement_0 IfcElement 1. GlobalId [1:1] 2. OwnerHistory [0:1] 3. Name [0:1] 4. Description [0:1]      HasAssignments [0:?]      Nests [0:1]      IsNestedBy [0:?]      HasContext [0:1] IsDecomposedBy      IsDecomposedBy [0:?]      Decomposes [0:1]      HasAssociations [0:?] 5. ObjectType [0:1]      IsDeclaredBy [0:1]      Declares [0:?]      IsTypedBy [0:1]      IsDefinedBy [0:?] 6. ObjectPlacement [0:1] 7. Representation [0:1]      ReferencedBy [0:?]      PositionedRelativeTo [0:?]      ReferencedInStructures [0:?] 8. Tag [0:1]      FillsVoids [0:1]      ConnectedTo [0:?]      IsInterferedByElements [0:?]      InterferesElements [0:?]      HasProjections [0:?]      HasOpenings [0:?]      IsConnectionRealization [0:?]      ProvidesBoundaries [0:?]      ConnectedFrom [0:?]      ContainedInStructure [0:1]      HasCoverings [0:?]      HasSurfaceFeatures [0:?] IfcRelAggregates IfcRelAggregates 1. GlobalId [1:1] 2. OwnerHistory [0:1] 3. Name [0:1] 4. Description [0:1] 5. RelatingObject [1:1] RelatedObjects 6. RelatedObjects [1:?] IfcElement_0:IsDecomposedBy1->IfcRelAggregates:RelatingObject0 IfcElement_1 IfcElement 1. GlobalId [1:1] 2. OwnerHistory [0:1] PartName 3. Name [0:1] 4. Description [0:1]      HasAssignments [0:?]      Nests [0:1]      IsNestedBy [0:?]      HasContext [0:1]      IsDecomposedBy [0:?]      Decomposes [0:1]      HasAssociations [0:?] 5. ObjectType [0:1]      IsDeclaredBy [0:1]      Declares [0:?]      IsTypedBy [0:1]      IsDefinedBy [0:?] 6. ObjectPlacement [0:1] 7. Representation [0:1]      ReferencedBy [0:?]      PositionedRelativeTo [0:?]      ReferencedInStructures [0:?] 8. Tag [0:1]      FillsVoids [0:1]      ConnectedTo [0:?]      IsInterferedByElements [0:?]      InterferesElements [0:?]      HasProjections [0:?]      HasOpenings [0:?]      IsConnectionRealization [0:?]      ProvidesBoundaries [0:?]      ConnectedFrom [0:?]      ContainedInStructure [0:1]      HasCoverings [0:?]      HasSurfaceFeatures [0:?] IfcRelAggregates:RelatedObjects1->IfcElement_1:IfcElement0 IfcLabel IfcLabel IfcElement_1:Name1->IfcLabel:IfcLabel0
Figure 4.4.1.2.A

General Usage

ApplicableEntity
RelatedObjects
IfcRelAggregates.RelatedObjects
IfcRamp IfcRampFlight
IfcRamp IfcSlab
IfcRamp IfcRailing
IfcRoof IfcSlab
IfcSlab IfcBuildingElementPart
IfcSlab IfcBeam
IfcSlab IfcCovering
IfcSlab IfcPlate
IfcStair IfcStairFlight
IfcStair IfcSlab
IfcStair IfcRailing
IfcWall IfcMember
IfcWall IfcMechanicalFastener
IfcWall IfcElementAssembly
IfcWall IfcBuildingElementPart
Table 4.4.1.2.B