IfcRelConnectsElements

Semantic definitions at the entity

Entity definition

The IfcRelConnectsElements objectified relationship provides the generalization of the connectivity between elements. It is a 1 to 1 relationship. The concept of two elements being physically or logically connected is described independently from the connecting elements. The connectivity may be related to the shape representation of the connected entities by providing a connection geometry.

In this case the geometrical constraints of the connection are provided by the optional relationship to the IfcConnectionGeometry. The connection geometry is provided as a point, curve or surface within the local placement coordinate systems of the connecting elements.
If the connection geometry is omitted then the connection is provided as a logical connection. Under this circumstance, the connection point, curve or surface has to be recalculated by the receiving application.

HISTORY New entity in IFC Release 1.0.

Attribute definitions

#	Attribute	Type	Cardinality	Description	A
5	ConnectionGeometry	-		This attribute is out of scope for this model view definition and shall not be set.
6	RelatingElement	IfcElement	[1:1]	Reference to an Element that is connected by the objectified relationship.	X
7	RelatedElement	IfcElement	[1:1]	Reference to an Element that is connected by the objectified relationship.	X

Formal Propositions

Rule	Description
WR31	The instance of the relating element shall not be the same instance as the related element.

Inherited definitions from supertypes

Entity inheritance

Attribute inheritance

#	Attribute	Type	Cardinality	Description	A
IfcRoot
1	GlobalId	IfcGloballyUniqueId	[1:1]	Assignment of a globally unique identifier within the entire software world.	X
2	OwnerHistory	IfcOwnerHistory	[1:1]	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 in stored.	X
3	Name	IfcLabel	[0:1]	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.	X
4	Description	IfcText	[0:1]	Optional description, provided for exchanging informative comments.	X
IfcRelationship
IfcRelConnects
IfcRelConnectsElements
5	ConnectionGeometry	-		This attribute is out of scope for this model view definition and shall not be set.
6	RelatingElement	IfcElement	[1:1]	Reference to an Element that is connected by the objectified relationship.	X
7	RelatedElement	IfcElement	[1:1]	Reference to an Element that is connected by the objectified relationship.	X

Formal representations

XSD Specification

 <xs:element name="IfcRelConnectsElements" type="ifc:IfcRelConnectsElements" substitutionGroup="ifc:IfcRelConnects" nillable="true"/>

 <xs:complexType name="IfcRelConnectsElements">

  <xs:complexContent>

   <xs:extension base="ifc:IfcRelConnects">

    <xs:sequence>

     <xs:element name="RelatingElement" type="ifc:IfcElement" nillable="true"/>

     <xs:element name="RelatedElement" type="ifc:IfcElement" nillable="true"/>

    </xs:sequence>

   </xs:extension>

  </xs:complexContent>

 </xs:complexType>

EXPRESS Specification


ENTITY IfcRelConnectsElements

 SUPERTYPE OF(IfcRelConnectsWithRealizingElements)

 SUBTYPE OF (IfcRelConnects);

  ConnectionGeometry : OPTIONAL IfcStrippedOptional;

  RelatingElement : IfcElement;

  RelatedElement : IfcElement;

 WHERE

  WR31 : RelatingElement :<>: RelatedElement;
END_ENTITY;

 EXPRESS-G diagram