6.1.3.28 IfcRelConnectsPathElements

6.1.3.28.1 Semantic definition

The IfcRelConnectsPathElements relationship provides the connectivity information between two elements, which have path information.

The objectified relationship provides the additional information required to describe the connection between two path based elements that might have single or multiple layers of material. The connection type specifies where at the path based element a connection is given (at the start, in the middle or at the end).

The connection is described by a connection geometry, given within the object coordinate systems of the RelatingElement and of the RelatedElement. In case of layered IfcWall elements as the RelatingElement and RelatedElement the connection geometry is provided by the subtype IfcConnectionCurveGeometry. Both curves indicate the so called "end cap", i.e. the curve that trims the wall outer edges (being parallel along the wall axis) at the end.

wall connection — Figure 6.1.3.28.A — Path connection geometry

Figure 6.1.3.28.A shows the application of IfcRelConnectsPathElements with the ConnectionGeometry of type IfcConnectionCurveGeometry. The example shows the connection relationship between two instances of layered IfcWall elements using the IfcRelConnectsPathElements relationship. The ConnectionCurveGeometry defines the CurveOnRelatingElement and CurveOnRelatedElement, both are of type IfcPolyline.

Figure 6.1.3.28.B illustrates using the IfcRelConnectsPathElements for a "T" type connection between two instances of layered IfcWall elements.

Figure 6.1.3.28.C illustrates using the IfcRelConnectsPathElements for a "L" type connection between two instances of layered IfcWall elements.

6.1.3.28.2 Entity inheritance

6.1.3.28.3 Attributes

#	Attribute	Type	Description
IfcRoot (4)
1	GlobalId	IfcGloballyUniqueId	Assignment of a globally unique identifier within the entire software world.
2	OwnerHistory	OPTIONAL IfcOwnerHistory	Assignment of the information about the current ownership of that object, including owning actor, application, local identification and information captured about the recent changes of the object, NOTE Only the last modification is stored - either as addition, deletion or modification. IFC4-CHANGE The attribute has been changed to be OPTIONAL.
3	Name	OPTIONAL IfcLabel	Optional name for use by the participating software systems or users. For some subtypes of IfcRoot the insertion of the Name attribute may be required. This would be enforced by a where rule.
4	Description	OPTIONAL IfcText	Optional description, provided for exchanging informative comments.
IfcRelConnectsElements (3)
5	ConnectionGeometry	OPTIONAL IfcConnectionGeometry	The geometric shape representation of the connection geometry that is provided in the object coordinate system of the RelatingElement (mandatory) and in the object coordinate system of the RelatedElement (optionally). NOTE ConnectionGeometry does not consider shape and position of the realizing element.
6	RelatingElement	IfcElement	Reference to a subtype of IfcElement that is connected by the connection relationship in the role of RelatingElement.
7	RelatedElement	IfcElement	Reference to a subtype of IfcElement that is connected by the connection relationship in the role of RelatedElement.
Click to show 7 hidden inherited attributes
IfcRelConnectsPathElements (4)
8	RelatingPriorities	LIST [0:?] OF IfcInteger	Overriding priorities at this connection. It overrides the standard priority given at the wall layer provided by IfcMaterialLayer.Priority. The list of RelatingProperties corresponds to the list of IfcMaterialLayerSet.MaterialLayers of the element referenced by RelatingObject.
9	RelatedPriorities	LIST [0:?] OF IfcInteger	Overriding priorities at this connection. It overrides the standard priority given at the wall layer provided by IfcMaterialLayer.Priority. The list of RelatedProperties corresponds to the list of IfcMaterialLayerSet.MaterialLayers of the element referenced by RelatedObject.
10	RelatedConnectionType	IfcConnectionTypeEnum	Indication of the connection type in relation to the path of the RelatedObject.
11	RelatingConnectionType	IfcConnectionTypeEnum	Indication of the connection type in relation to the path of the RelatingObject.

Table 6.1.3.28.E

6.1.3.28.4 Formal propositions

Name Description

NormalizedRelatedPriorities

The RelatedProperties shall all be given as a normalized integer range [0..100], where 0 is the lowest and 100 the highest priority of the material layers.

 (SIZEOF(RelatedPriorities) = 0)
OR
(SIZEOF (QUERY (temp <* RelatedPriorities
  | {0 <= temp <= 100}
  )) = SIZEOF(RelatedPriorities))

NormalizedRelatingPriorities

The RelatingProperties shall all be given as a normalized integer range [0..100], where 0 is the lowest and 100 the highest priority of the material layers.

 (SIZEOF(RelatingPriorities) = 0)
OR
(SIZEOF (QUERY (temp <* RelatingPriorities
  | {0 <= temp <= 100}
  )) = SIZEOF(RelatingPriorities))

Table 6.1.3.28.F

6.1.3.28.5 Concept usage

Concept	Usage	Description
IfcRoot (2)
Revision Control	General	Ownership, history, and merge state is captured using IfcOwnerHistory.
Software Identity	General	IfcRoot assigns the globally unique ID. In addition it may provide for a name and a description about the concept.
Click to show 2 hidden inherited concepts

Table 6.1.3.28.G

6.1.3.28.6 Examples

Figure 6.1.3.28.D

Construction Scheduling Task

6.1.3.28.7 Formal representation

 ENTITY IfcRelConnectsPathElements
 SUBTYPE OF (IfcRelConnectsElements);
	RelatingPriorities : LIST [0:?] OF IfcInteger;
	RelatedPriorities : LIST [0:?] OF IfcInteger;
	RelatedConnectionType : IfcConnectionTypeEnum;
	RelatingConnectionType : IfcConnectionTypeEnum;
 WHERE
	NormalizedRelatedPriorities : (SIZEOF(RelatedPriorities) = 0)
OR
(SIZEOF (QUERY (temp <* RelatedPriorities
  | {0 <= temp <= 100}
  )) = SIZEOF(RelatedPriorities));
	NormalizedRelatingPriorities : (SIZEOF(RelatingPriorities) = 0)
OR
(SIZEOF (QUERY (temp <* RelatingPriorities
  | {0 <= temp <= 100}
  )) = SIZEOF(RelatingPriorities));
END_ENTITY;

6.1.3.28.8 References

IfcRelConnectsElements