IfcSlabType

Natural language names
deDecke / Dachfläche / Bodenplatte - Typ
enSlab Type
frType de dalle
Change log
ItemSPFXMLChangeDescription
IFC2x3 to IFC4
    IfcSlabType
      OwnerHistoryMODIFIEDInstantiation changed to OPTIONAL.
      ApplicableOccurrenceMODIFIEDType changed from IfcLabel to IfcIdentifier.
Semantic definitions at the entity
Entity definition

The element type IfcSlabType defines commonly shared information for occurrences of slabs. The set of shared information may include:

NOTE  It is illegal to share shape representations as representation maps for occurrences of IfcSlabStandardCase.

It is used to define a slab specification (i.e. the specific product information, that is common to all occurrences of that product type). Slab types may be exchanged without being already assigned to occurrences.

NOTE  The product representations are defined as representation maps (at the level of the supertype IfcTypeProduct, which gets assigned by an element occurrence instance through the IfcShapeRepresentation.Item[1] being an IfcMappedItem.

The occurrences of the IfcSlabType within building models are represented by instances of IfcSlabStandardCase if the IfcSlabType has a single associated IfcMaterialLayerSet; otherwise they are represented by instances of IfcSlab, or IfcSlabElementedCase.

HISTORY  New entity in IFC2x2.

Informal Propositions:

  1. The material assignment, if provided using the IfcRelAssociatesMaterial relationship, shall not reference the IfcMaterialLayerSetUsage.
Attribute definitions
#AttributeTypeCardinalityDescription C
10PredefinedTypeIfcSlabTypeEnum[1:1] Identifies the predefined types of a slab element from which the type required may be set.X
Formal Propositions
RuleDescription
CorrectPredefinedTypeThe inherited attribute ElementType shall be provided, if the PredefinedType is set to USERDEFINED.
Inherited definitions from supertypes
Entity inheritance IfcBuildingElementType IfcElementType IfcTypeProduct IfcTypeObject IfcObjectDefinition IfcRoot
Attribute inheritance
#AttributeTypeCardinalityDescriptionC
IfcRoot
1GlobalIdIfcGloballyUniqueId[1:1] Assignment of a globally unique identifier within the entire software world. X
2OwnerHistoryIfcOwnerHistory[0:1] 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 - either as addition, deletion or modification.
X
3NameIfcLabel[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
4DescriptionIfcText[0:1] Optional description, provided for exchanging informative comments.X
IfcObjectDefinition
HasAssignmentsIfcRelAssigns
@RelatedObjects		S[0:?]Reference to the relationship objects, that assign (by an association relationship) other subtypes of IfcObject to this object instance. Examples are the association to products, processes, controls, resources or groups.X
NestsIfcRelNests
@RelatedObjects		S[0:1]References to the decomposition relationship being a nesting. It determines that this object definition is a part within an ordered whole/part decomposition relationship. An object occurrence or type can only be part of a single decomposition (to allow hierarchical strutures only). X
IsNestedByIfcRelNests
@RelatingObject		S[0:?]References to the decomposition relationship being a nesting. It determines that this object definition is the whole within an ordered whole/part decomposition relationship. An object or object type can be nested by several other objects (occurrences or types). X
HasContextIfcRelDeclares
@RelatedDefinitions		S[0:1]References to the context providing context information such as project unit or representation context. It should only be asserted for the uppermost non-spatial object. X
IsDecomposedByIfcRelAggregates
@RelatingObject		S[0:?]References to the decomposition relationship being an aggregation. It determines that this object definition is whole within an unordered whole/part decomposition relationship. An object definitions can be aggregated by several other objects (occurrences or parts). X
DecomposesIfcRelAggregates
@RelatedObjects		S[0:1]References to the decomposition relationship being an aggregation. It determines that this object definition is a part within an unordered whole/part decomposition relationship. An object definitions can only be part of a single decomposition (to allow hierarchical strutures only). X
HasAssociationsIfcRelAssociates
@RelatedObjects		S[0:?]Reference to the relationship objects, that associates external references or other resource definitions to the object.. Examples are the association to library, documentation or classification.X
IfcTypeObject
5ApplicableOccurrenceIfcIdentifier[0:1] The attribute optionally defines the data type of the occurrence object, to which the assigned type object can relate. If not present, no instruction is given to which occurrence object the type object is applicable. The following conventions are used:
  • The IFC entity name of the applicable occurrence using the IFC naming convention, CamelCase with IFC prefix
  • It can be optionally followed by the predefined type after the separator "/" (forward slash), using uppercase
  • If one type object is applicable to many occurrence objects, then those occurrence object names should be separate by comma "," forming a comma separated string.
EXAMPLE Refering to a furniture as applicable occurrence entity would be expressed as 'IfcFurnishingElement', refering to a brace as applicable entity would be expressed as 'IfcMember/BRACE', refering to a wall and wall standard case would be expressed as 'IfcWall, IfcWallStandardCase'.
X
6HasPropertySetsIfcPropertySetDefinitionS[1:?] Set list of unique property sets, that are associated with the object type and are common to all object occurrences referring to this object type. X
TypesIfcRelDefinesByType
@RelatingType		S[0:1]Reference to the relationship IfcRelDefinedByType and thus to those occurrence objects, which are defined by this type.X
IfcTypeProduct
7RepresentationMapsIfcRepresentationMap~L[1:?] List of unique representation maps. Each representation map describes a block definition of the shape of the product style. By providing more than one representation map, a multi-view block definition can be given.X
8TagIfcLabel[0:1] The tag (or label) identifier at the particular type of a product, e.g. the article number (like the EAN). It is the identifier at the specific level.X
ReferencedByIfcRelAssignsToProduct
@RelatingProduct		S[0:?]Reference to the IfcRelAssignsToProduct relationship, by which other products, processes, controls, resources or actors (as subtypes of IfcObjectDefinition) can be related to this product type. X
IfcElementType
9ElementTypeIfcLabel[0:1] The type denotes a particular type that indicates the object further. The use has to be established at the level of instantiable subtypes. In particular it holds the user defined type, if the enumeration of the attribute 'PredefinedType' is set to USERDEFINED. X
IfcBuildingElementType
IfcSlabType
10PredefinedTypeIfcSlabTypeEnum[1:1] Identifies the predefined types of a slab element from which the type required may be set.X
Definitions applying to Common Use Definitions

 Instance diagram

Concept usage

Material Layer Set

The Material Layer Set concept applies to this entity.

The material of the IfcSlabType is defined by the IfcMaterialLayerSet or as fall back by IfcMaterial and attached by the IfcRelAssociatesMaterial.RelatingMaterial. It is accessible by the inverse HasAssociations relationship.

NOTE  It is illegal to assign an IfcMaterial to an IfcSlabType, if there is at least one occurrences. of IfcSlabStandardCase for this type.

The shared material layer set definition is defined by assigning an IfcMaterialLayerSet (see material use definition above). The IfcMaterialLayer refers to one or several of IfcMaterial that is the common for all slab occurrence, if used. It is only applicable if the IfcSlabType has only occurrences of type IfcSlabStandardCase (see definition of IfcSlabStandardCase for further information).

NOTE  Since each individual instance of IfcSlabStandardCase defines its own IfcMaterialLayerSetUsage including the offset from the reference plane, the same IfcSlabType can be used independently of the reference plane alignment of its occurrences.


Type Body Geometry

The Type Body Geometry concept applies to this entity.



Concept inheritance

#ConceptModel View
IfcRoot
Software IdentityCommon Use Definitions
Revision ControlCommon Use Definitions
IfcTypeProduct
Product Type ShapeCommon Use Definitions
IfcSlabType
Material Layer SetCommon Use Definitions
Type Body GeometryCommon Use Definitions
Examples
Formal representations
XSD Specification
 <xs:element name="IfcSlabType" type="ifc:IfcSlabType" substitutionGroup="ifc:IfcBuildingElementType" nillable="true"/>
 <xs:complexType name="IfcSlabType">
  <xs:complexContent>
   <xs:extension base="ifc:IfcBuildingElementType">
    <xs:attribute name="PredefinedType" type="ifc:IfcSlabTypeEnum" use="optional"/>
   </xs:extension>
  </xs:complexContent>
 </xs:complexType>
EXPRESS Specification
ENTITY IfcSlabType
 SUBTYPE OF (IfcBuildingElementType);
  PredefinedType : IfcSlabTypeEnum;
 WHERE
  CorrectPredefinedType : (PredefinedType <> IfcSlabTypeEnum.USERDEFINED) OR ((PredefinedType = IfcSlabTypeEnum.USERDEFINED) AND EXISTS(SELF\IfcElementType.ElementType));
END_ENTITY;

Link to EXPRESS-G diagram EXPRESS-G diagram

Link to this page  Link to this page