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 IFC1.0.

Attribute definitions

#	Attribute	Type	Cardinality	Description	G
5	ConnectionGeometry	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).	X
6	RelatingElement	IfcElement		Reference to a subtype of IfcElement that is connected by the connection relationship in the role of RelatingElement.	X
7	RelatedElement	IfcElement		Reference to a subtype of IfcElement that is connected by the connection relationship in the role of RelatedElement.	X

Formal Propositions

Rule	Description
NoSelfReference	The instance of the RelatingElement shall not be the same instance as the RelatedElement.

Inherited definitions from supertypes

Entity inheritance

Attribute inheritance

#	Attribute	Type	Cardinality	Description	G
IfcRoot
1	GlobalId	IfcGloballyUniqueId		Assignment of a globally unique identifier within the entire software world.	X
2	OwnerHistory	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 in stored - either as addition, deletion or modification. IFC4 CHANGE The attribute has been changed to be OPTIONAL.	X
3	Name	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.	X
4	Description	IfcText	?	Optional description, provided for exchanging informative comments.	X
IfcRelationship
IfcRelConnects
IfcRelConnectsElements
5	ConnectionGeometry	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).	X
6	RelatingElement	IfcElement		Reference to a subtype of IfcElement that is connected by the connection relationship in the role of RelatingElement.	X
7	RelatedElement	IfcElement		Reference to a subtype of IfcElement that is connected by the connection relationship in the role of RelatedElement.	X

#	Concept	Template	Model View
IfcRoot
	Identity	Software Identity	General Usage
	Revision Control	Revision Control	General Usage

Formal representations

XML 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="ConnectionGeometry" type="ifc:IfcConnectionGeometry" nillable="true" minOccurs="0"/>

     <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(ONEOF(IfcRelConnectsPathElements, IfcRelConnectsWithRealizingElements))

 SUBTYPE OF (IfcRelConnects);

  ConnectionGeometry : OPTIONAL IfcConnectionGeometry;

  RelatingElement : IfcElement;

  RelatedElement : IfcElement;

 WHERE

  NoSelfReference : RelatingElement :<>: RelatedElement;
END_ENTITY;

 EXPRESS-G diagram

Item	Change	Description
IFC2x3 to IFC4
IfcRelConnectsElements
OwnerHistory	MODIFIED	Instantiation changed to OPTIONAL.

	Verbindet Elemente - Relation
	Rel Connects Elements
	Connection d'éléments

IfcRelConnectsElements

Semantic definitions at the entity

Inherited definitions from supertypes

Definitions applying to General Usage

Formal representations