6.3.3.1 IfcBuildingElementPart

Partie d'élément de construction
Teil eines Bauelements

IfcBuildingElementPart represents major components as subordinate parts of a building element. Typical usage examples include precast concrete sandwich walls, where the layers may have different geometry representations. In this case the layered material representation does not sufficiently describe the element. Each layer is represented by an own instance of the IfcBuildingElementPart with its own geometry description.

The kind of building element part is further specified by a corresponding instance of IfcBuildingElementPartType, referred to by IfcRelDefinesByType.

HISTORY  New entity in IFC2x2.
IFC4 CHANGE  Moved from IfcStructuralElementsDomain schema to IfcSharedComponentElements schema, compatible change of supertype, attribute PredefinedType added.

XSD Specification:

 <xs:element name="IfcBuildingElementPart" type="ifc:IfcBuildingElementPart" substitutionGroup="ifc:IfcElementComponent" nillable="true"/>
 <xs:complexType name="IfcBuildingElementPart">
  <xs:complexContent>
   <xs:extension base="ifc:IfcElementComponent">
    <xs:attribute name="PredefinedType" type="ifc:IfcBuildingElementPartTypeEnum" use="optional"/>
   </xs:extension>
  </xs:complexContent>
 </xs:complexType>

EXPRESS Specification:

ENTITY IfcBuildingElementPart
SUBTYPE OF IfcElementComponent;
PredefinedType : OPTIONAL IfcBuildingElementPartTypeEnum;
WHERE
CorrectPredefinedType : NOT(EXISTS(PredefinedType)) OR (PredefinedType <> IfcBuildingElementPartTypeEnum.USERDEFINED) OR ((PredefinedType = IfcBuildingElementPartTypeEnum.USERDEFINED) AND EXISTS (SELF\IfcObject.ObjectType));
CorrectTypeAssigned : (SIZEOF(IsTypedBy) = 0) OR ('IFCSHAREDCOMPONENTELEMENTS.IFCBUILDINGELEMENTPARTTYPE' IN TYPEOF(SELF\IfcObject.IsTypedBy[1].RelatingType));
END_ENTITY;

Link to EXPRESS-G diagram EXPRESS-G diagram

Attribute Definitions:

PredefinedType : Subtype of building element part

Formal Propositions:

CorrectPredefinedType : Either the PredefinedType attribute is unset (e.g. because an IfcBuildingElementPartType is associated), or the inherited attribute ObjectType shall be provided, if the PredefinedType is set to USERDEFINED.
CorrectTypeAssigned : If this occurrence is defined by a type object, the latter has to be an IfcBuildingElementPartType.

Inheritance Graph:

ENTITY IfcBuildingElementPart
ENTITY IfcRoot
GlobalId : IfcGloballyUniqueId;
OwnerHistory : OPTIONAL IfcOwnerHistory;
Name : OPTIONAL IfcLabel;
Description : OPTIONAL IfcText;
ENTITY IfcObjectDefinition
INVERSE
HasAssignments : SET OF IfcRelAssigns FOR RelatedObjects;
Nests : SET [0:1] OF IfcRelNests FOR RelatedObjects;
IsNestedBy : SET OF IfcRelNests FOR RelatingObject;
HasContext : SET [0:1] OF IfcRelDeclares FOR RelatedDefinitions;
IsDecomposedBy : SET OF IfcRelAggregates FOR RelatingObject;
Decomposes : SET [0:1] OF IfcRelAggregates FOR RelatedObjects;
HasAssociations : SET OF IfcRelAssociates FOR RelatedObjects;
ENTITY IfcObject
ObjectType : OPTIONAL IfcLabel;
INVERSE
IsDeclaredBy : SET [0:1] OF IfcRelDefinesByObject FOR RelatedObjects;
Declares : SET OF IfcRelDefinesByObject FOR RelatingObject;
IsTypedBy : SET [0:1] OF IfcRelDefinesByType FOR RelatedObjects;
IsDefinedBy : SET OF IfcRelDefinesByProperties FOR RelatedObjects;
ENTITY IfcProduct
ObjectPlacement : OPTIONAL IfcObjectPlacement;
Representation : OPTIONAL IfcProductRepresentation;
INVERSE
ReferencedBy : SET OF IfcRelAssignsToProduct FOR RelatingProduct;
ENTITY IfcElement
Tag : OPTIONAL IfcIdentifier;
INVERSE
FillsVoids : SET [0:1] OF IfcRelFillsElement FOR RelatedBuildingElement;
ConnectedTo : SET OF IfcRelConnectsElements FOR RelatingElement;
IsInterferedByElements : SET OF IfcRelInterferesElements FOR RelatedElement;
InterferesElements : SET OF IfcRelInterferesElements FOR RelatingElement;
HasProjections : SET OF IfcRelProjectsElement FOR RelatingElement;
ReferencedInStructures : SET OF IfcRelReferencedInSpatialStructure FOR RelatedElements;
HasOpenings : SET OF IfcRelVoidsElement FOR RelatingBuildingElement;
IsConnectionRealization : SET OF IfcRelConnectsWithRealizingElements FOR RealizingElements;
ProvidesBoundaries : SET OF IfcRelSpaceBoundary FOR RelatedBuildingElement;
ConnectedFrom : SET OF IfcRelConnectsElements FOR RelatedElement;
ContainedInStructure : SET [0:1] OF IfcRelContainedInSpatialStructure FOR RelatedElements;
ENTITY IfcElementComponent
ENTITY IfcBuildingElementPart
PredefinedType : OPTIONAL IfcBuildingElementPartTypeEnum;
END_ENTITY;

Link to this page  Link to this page