IfcPlate

Semantic definitions at the entity

Entity definition

An IfcPlate is a planar and often flat part with constant thickness. A plate may carry loads between or beyond points of support, or provide stiffening. The location of the plate (being horizontal, vertical or sloped) is not relevant to its definition (in contrary to IfcWall and IfcSlab (as floor slab)).

NOTE Definition according to ISO 6707-1: thin, rigid, flat, metal product, of a thickness greater than that of a sheet.

Plates are normally made of steel, other metallic material, or by glass panels. However the definition of IfcPlate is material independent and specific material information shall be handled by using IfcAssociatesMaterial to assign a material specification to the IfcPlate.

NOTE Although not necessarily, plates are often add-on parts. This is represented by the IfcRelAggregates decomposition mechanism used to aggregate parts, such as IfcPlate, into a container element such as IfcElementAssembly or IfcCurtainWall.

NOTE The representation of a plate in a structural analysis model is provided by IfcStructuralSurfaceMember being part of an IfcStructuralAnalysisModel.

An instance IfcPlate should preferably get its geometric representation and material assignment through the type definition by IfcPlateType assigned using the IfcRelDefinesByType relationship. This allows identical plates in a construction to be represented by the same instance of IfcPlateType.

A plate may have openings, such as voids or recesses. They are defined by an IfcOpeningElement attached to the plate using the inverse relationship HasOpenings pointing to IfcRelVoidsElement. The position number of a plate as often used in steel construction is assigned through the attribute IfcElement.Tag

The IFC specification provides two entities for plate occurrences:

IfcPlateStandardCase used for all occurrences of plates, that are prismatic and where the thickness parameter can be fully described by the IfcMaterialLayerSetUsage. These plates are always represented geometrically by a 'SweptSolid' geometry (or by a 'Clipping' geometry based on 'SweptSolid'), if a 3D geometric representation is assigned. In addition they have to have a corresponding IfcMaterialLayerSetUsage assigned.
IfcPlate used for all other occurrences of plates, particularly for plates with changing thickness, or plates with non planar surfaces, and plates having only 'SurfaceModel' or 'Brep' geometry.

HISTORY New entity in IFC2x2

Attribute definitions

#	Attribute	Type	Cardinality	Description	B
9	PredefinedType	IfcPlateTypeEnum	[0:1]	Predefined generic type for a plate that is specified in an enumeration. There may be a property set given specificly for the predefined types. NOTE The PredefinedType shall only be used, if no IfcPlateType is assigned, providing its own IfcPlateType.PredefinedType.	X

Formal Propositions

Rule	Description
CorrectPredefinedType	Either the PredefinedType attribute is unset (e.g. because an IfcPlateType is associated), or the inherited attribute ObjectType shall be provided, if the PredefinedType is set to USERDEFINED.
CorrectTypeAssigned	Either there is no plate type object associated, i.e. the IsTypedBy inverse relationship is not provided, or the associated type object has to be of type IfcPlateType.

Inherited definitions from supertypes

Entity inheritance

Attribute inheritance

#	Attribute	Type	Cardinality	Description	B
IfcRoot
1	GlobalId	IfcGloballyUniqueId	[1:1]	Assignment of a globally unique identifier within the entire software world.	X
2	OwnerHistory	IfcOwnerHistory	[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
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
IfcObjectDefinition
	HasAssignments	IfcRelAssigns @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
	Nests	IfcRelNests @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).
	IsNestedBy	IfcRelNests @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
	HasContext	IfcRelDeclares @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.
	IsDecomposedBy	IfcRelAggregates @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
	Decomposes	IfcRelAggregates @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
	HasAssociations	IfcRelAssociates @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
IfcObject
5	ObjectType	-		This attribute is out of scope for this model view definition and shall not be set.
	IsTypedBy	IfcRelDefinesByType @RelatedObjects	S[0:1]	Set of relationships to the object type that provides the type definitions for this object occurrence. The then associated IfcTypeObject, or its subtypes, contains the specific information (or type, or style), that is common to all instances of IfcObject, or its subtypes, referring to the same type.	X
	IsDefinedBy	IfcRelDefinesByProperties @RelatedObjects	S[0:?]	Set of relationships to property set definitions attached to this object. Those statically or dynamically defined properties contain alphanumeric information content that further defines the object.	X
IfcProduct
6	ObjectPlacement	IfcObjectPlacement	[0:1]	Placement of the product in space, the placement can either be absolute (relative to the world coordinate system), relative (relative to the object placement of another product), or constraint (e.g. relative to grid axes). It is determined by the various subtypes of IfcObjectPlacement, which includes the axis placement information to determine the transformation for the object coordinate system.	X
7	Representation	IfcProductRepresentation	[0:1]	Reference to the representations of the product, being either a representation (IfcProductRepresentation) or as a special case a shape representations (IfcProductDefinitionShape). The product definition shape provides for multiple geometric representations of the shape property of the object within the same object coordinate system, defined by the object placement.	X
	ReferencedBy	IfcRelAssignsToProduct @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.	X
IfcElement
8	Tag	IfcIdentifier	[0:1]	The tag (or label) identifier at the particular instance of a product, e.g. the serial number, or the position number. It is the identifier at the occurrence level.	X
	ConnectedTo	IfcRelConnectsElements @RelatingElement	S[0:?]	Reference to the element connection relationship. The relationship then refers to the other element to which this element is connected to.
	HasOpenings	IfcRelVoidsElement @RelatingBuildingElement	S[0:?]	Reference to the IfcRelVoidsElement relationship that creates an opening in an element. An element can incorporate zero-to-many openings. For each opening, that voids the element, a new relationship IfcRelVoidsElement is generated.	X
	ConnectedFrom	IfcRelConnectsElements @RelatedElement	S[0:?]	Reference to the element connection relationship. The relationship then refers to the other element that is connected to this element.	X
	ContainedInStructure	IfcRelContainedInSpatialStructure @RelatedElements	S[0:1]	Containment relationship to the spatial structure element, to which the element is primarily associated. This containment relationship has to be hierachical, i.e. an element may only be assigned directly to zero or one spatial structure.
	PositionedFrom	IfcRelPositions @RelatingElement	S[0:1]	Indicates a constrained placement, where the ObjectPosition must match positioning defined according to the referenced positioning element.	X
IfcBuildingElement
IfcPlate
9	PredefinedType	IfcPlateTypeEnum	[0:1]	Predefined generic type for a plate that is specified in an enumeration. There may be a property set given specificly for the predefined types. NOTE The PredefinedType shall only be used, if no IfcPlateType is assigned, providing its own IfcPlateType.PredefinedType.	X

Definitions applying to Bridge View

Instance diagram

Plates are used to represent planar surfaces with primary function of resisting bending such as stiffeners or gusset plates. The general definition IfcPlate defines a fixed shape, while the subtype IfcPlateStandardCase allows for parametric resizing.

Concept usage

Object Typing

The Object Typing concept applies to this entity as shown in Table 39.

Type
IfcPlateType

Table 39 — IfcPlate Object Typing

Exchange
Import		O
Export		O

Quantity Sets

The Quantity Sets concept applies to this entity as shown in Table 40.

Name
Qto_PlateBaseQuantities

Table 40 — IfcPlate Quantity Sets

Exchange
Import		O
Export		O

Surface Connectivity

The Surface Connectivity concept applies to this entity as shown in Table 41.

Type	Description
IfcBeam	Plates may be attached to beams, functioning as stiffeners or gusset plates.

Table 41 — IfcPlate Surface Connectivity

This relationship is used to indicate connections between plates and other elements such as beams (girders). The intersecting surface may be provided to indicate precisely where the member is attached, and to assist fabrication for indicating contour marking and/or weld locations.

Exchange
Import		R		R
Export		R		R

Body SweptSolid Extruded Arbitrary Geometry

The Body SweptSolid Extruded Arbitrary Geometry concept applies to this entity.

Exchange
Import		O		O
Export		O		O

Annotation 2D Geometry

The Annotation 2D Geometry concept applies to this entity as shown in Table 42.

Identifier	Type	Items	Description
		IfcTextLiteralWithExtent	Piece marks.
		IfcCartesianPoint	Pop marks.
		IfcIndexedPolyCurve	Contour marks.

Table 42 — IfcPlate Annotation 2D Geometry

Piece marks, pop marks, and contour marks may be designated using the 'Annotation' representation.

Exchange
Import				O
Export				O

Product Assignment

The Product Assignment concept applies to this entity as shown in Table 43.

Type	Description
IfcStructuralSurfaceMember	Idealized structural representation of plate.
IfcTask	Tasks assigned to bridge components indicating applicable construction phases

Table 43 — IfcPlate Product Assignment

Exchange
Import		O
Export		O

Element Nesting

The Element Nesting concept applies to this entity as shown in Table 44.

Type	PredefinedType
IfcPlate

Table 44 — IfcPlate Element Nesting

The nesting relationship may be used to indicate nesting of plates onto sheets of material.

Exchange
Import				R
Export				R

Concept inheritance

#	Concept	Model View
IfcRoot
	Software Identity	Bridge View
	User Identity	Bridge View
	Object Ownership	Bridge View
IfcObject
	Property Sets for Objects	Bridge View
IfcElement
	Element Occurrence Attributes	Bridge View
	Product Local Placement	Bridge View
IfcPlate
	Object Typing	Bridge View
	Quantity Sets	Bridge View
	Surface Connectivity	Bridge View
	Body SweptSolid Extruded Arbitrary Geometry	Bridge View
	Annotation 2D Geometry	Bridge View
	Product Assignment	Bridge View
	Element Nesting	Bridge View

Formal representations

XSD Specification

 <xs:element name="IfcPlate" type="ifc:IfcPlate" substitutionGroup="ifc:IfcBuildingElement" nillable="true"/>

 <xs:complexType name="IfcPlate">

  <xs:complexContent>

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

    <xs:attribute name="PredefinedType" type="ifc:IfcPlateTypeEnum" use="optional"/>

   </xs:extension>

  </xs:complexContent>

 </xs:complexType>

EXPRESS Specification


ENTITY IfcPlate

 SUPERTYPE OF(IfcPlateStandardCase)

 SUBTYPE OF (IfcBuildingElement);

  PredefinedType : OPTIONAL IfcPlateTypeEnum;

 WHERE

  CorrectPredefinedType : NOT(EXISTS(PredefinedType)) OR
 (PredefinedType <> IfcPlateTypeEnum.USERDEFINED) OR
 ((PredefinedType = IfcPlateTypeEnum.USERDEFINED) AND EXISTS (SELF\IfcObject.ObjectType));
  CorrectTypeAssigned : (SIZEOF(IsTypedBy) = 0) OR
  ('IFCSHAREDBLDGELEMENTS.IFCPLATETYPE' IN TYPEOF(SELF\IfcObject.IsTypedBy[1].RelatingType));
END_ENTITY;

 EXPRESS-G diagram

Link to this page

Item	Change	Description
IFC2x3 to IFC4
IfcPlate
OwnerHistory	MODIFIED	Instantiation changed to OPTIONAL.
PredefinedType	ADDED
IFC4x1 to IFC4x2
IfcPlate
PositionedFrom	ADDED

	Platte / Paneel
	Plate
	Plaque