IFC 4.3.x development

5.4.3.54 IfcRelReferencedInSpatialStructure

Change log

IFC4

additions where_rules AllowedRelatedElements
deletions where_rules WR31
modificationsattributes RelatingStructure definitionChanged from IfcSpatialStructureElement to IfcSpatialElement

IFC4X1

additionswhere_rulesAllowedRelatedElements
deletionswhere_rulesAllowedRelatedElements

IFC4X2

additionswhere_rulesAllowedRelatedElements
deletionswhere_rulesAllowedRelatedElements

IFC4X3_RC3

additions where_rules AllowedRelatedElements
deletions where_rules AllowedRelatedElements
modificationsattributes RelatedElements definitionChanged from set[1:?] of IfcProduct to set[1:?] of IfcSpatialReferenceSelect

5.4.3.54.1 Semantic definitions at the entity

The objectified relationship, IfcRelReferencedInSpatialStructure is used to assign elements in addition to those levels of the project spatial structure, in which they are referenced, but not primarily contained. It is also used to connect a system to the relevant spatial element that it serves.

NOTE  The primary containment relationship between an element and the spatial structure is handled by IfcRelContainedInSpatialStructure.

Any element can be referenced to zero, one or several levels of the spatial structure. Whereas the IfcRelContainedInSpatialStructure relationship is required to be hierarchical (an element can only be contained in exactly one spatial structure element), the IfcRelReferencedInSpatialStructure is not restricted to be hierarchical.

EXAMPLE  A wall might be normally contained within a storey, and since it does not span through several stories, it is not referenced in any additional storey. However a curtain wall might span through several stories, in this case it can be contained within the ground floor, but it would be referenced by all additional stories, it spans.

Predefined spatial structure elements to which elements can be assigned are

Elements can also be references in a spatial zone that is provided as IfcSpatialZone.

Figure 1 shows the use of IfcRelContainedInSpatialStructure and IfcRelReferencedInSpatialStructure to assign an IfcCurtainWall to two different levels within the spatial structure. It is primarily contained within the ground floor, and additionally referenced within the first and second floor.

"reference and containment"

HISTORY  New entity in IFC2x3.

5.4.3.54.1 Attributes

#Attribute Type Description
IfcRoot
1GlobalId IfcGloballyUniqueId Assignment of a globally unique identifier within the entire software world.
2OwnerHistory 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 in stored - either as addition, deletion or modification.

> IFC4 CHANGE  The attribute has been changed to be OPTIONAL.
3Name 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.
4Description OPTIONAL IfcText Optional description, provided for exchanging informative comments.
IfcRelationship
IfcRelConnects
IfcRelReferencedInSpatialStructure
5RelatedElements SET [1:?] OF IfcSpatialReferenceSelect
6RelatingStructureIfcSpatialElement

5.4.3.54.2 Entity inheritance

dot_inheritance IfcRelReferencedInSpatialStructure IfcRelReferencedInSpatialStructure IfcRelConnects IfcRelConnects IfcRelReferencedInSpatialStructure->IfcRelConnects IfcRelConnects_children 15 more... IfcRelConnects_children->IfcRelConnects IfcRelationship IfcRelationship IfcRelConnects->IfcRelationship IfcRelationship_children 5 more... IfcRelationship_children->IfcRelationship IfcRoot IfcRoot IfcRelationship->IfcRoot IfcObjectDefinition IfcObjectDefinition IfcObjectDefinition->IfcRoot IfcPropertyDefinition IfcPropertyDefinition IfcPropertyDefinition->IfcRoot

5.4.3.54.3 Definitions applying to General Usage

5.4.3.54.3.1 Identity

IfcRoot assigns the globally unique ID. In addition it may provide for a name and a description about the concept.

5.4.3.54.3.2 Revision Control

Ownership, history, and merge state is captured using IfcOwnerHistory.

5.4.3.54.4 Formal representations

ENTITY IfcRelReferencedInSpatialStructure
 SUBTYPE OF (IfcRelConnects);
	RelatedElements : SET [1:?] OF IfcSpatialReferenceSelect;
	RelatingStructure : IfcSpatialElement;
 WHERE
	AllowedRelatedElements : SIZEOF(QUERY(temp <* RelatedElements | ('IFC4X3_DEV_a1492713.IFCSPATIALSTRUCTUREELEMENT' IN TYPEOF(temp)) AND (NOT ('IFC4X3_DEV_a1492713.IFCSPACE' IN TYPEOF(temp)))
)) = 0;
END_ENTITY;