IFC 4.3.0.0 (IFC4X3) final

6.1.3.18 IfcMember

6.1.3.18.1 Semantic definition

An IfcMember is a structural member designed to carry loads between or beyond points of support. It is not required to be load bearing. The orientation of the member (being horizontal, vertical or sloped) is not relevant to its definition (in contrary to IfcBeam and IfcColumn). An IfcMember represents a linear structural element from an architectural or structural modeling point of view and shall be used if it cannot be expressed more specifically as either an IfcBeam or an IfcColumn.

There are two main representations for member occurrences:

  • IfcMember with IfcMaterialProfileSetUsage is used for all occurrences of members, that have a profile defined that is swept along a directrix. The profile might be changed uniformly by a taper definition along the directrix. The profile parameter and its cardinal point of insertion can be fully described by the IfcMaterialProfileSetUsage. These members are always represented geometricly by an 'Axis' and a 'SweptSolid' or 'AdvancedSweptSolid' shape representation (or by a 'Clipping' geometry based on the swept solid), if a 3D geometric representation is assigned.
  • IfcMember without IfcMaterialProfileSetUsage is used for all other occurrences of members, particularly for members with changing profile sizes along the extrusion, or members defined by non-linear extrusion, or members having only 'Brep', or 'SurfaceModel' geometry, or if a more parametric representation is not intended.

6.1.3.18.2 Entity inheritance

6.1.3.18.3 Attributes

# Attribute Type Description
IfcRoot (4)
1 GlobalId IfcGloballyUniqueId

Assignment of a globally unique identifier within the entire software world.

2 OwnerHistory 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,

3 Name 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.

4 Description OPTIONAL IfcText

Optional description, provided for exchanging informative comments.

IfcObjectDefinition (7)
HasAssignments SET [0:?] OF IfcRelAssigns FOR RelatedObjects

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.

Nests SET [0:1] OF IfcRelNests FOR RelatedObjects

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 SET [0:?] OF IfcRelNests FOR RelatingObject

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).

HasContext SET [0:1] OF IfcRelDeclares FOR RelatedDefinitions

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 SET [0:?] OF IfcRelAggregates FOR RelatingObject

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).

Decomposes SET [0:1] OF IfcRelAggregates FOR RelatedObjects

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).

HasAssociations SET [0:?] OF IfcRelAssociates FOR RelatedObjects

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.

IfcObject (5)
5 ObjectType OPTIONAL IfcLabel

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.

IsDeclaredBy SET [0:1] OF IfcRelDefinesByObject FOR RelatedObjects

Link to the relationship object pointing to the declaring object that provides the object definitions for this object occurrence. The declaring object has to be part of an object type decomposition. The associated IfcObject, or its subtypes, contains the specific information (as part of a type, or style, definition), that is common to all reflected instances of the declaring IfcObject, or its subtypes.

Declares SET [0:?] OF IfcRelDefinesByObject FOR RelatingObject

Link to the relationship object pointing to the reflected object(s) that receives the object definitions. The reflected object has to be part of an object occurrence decomposition. The associated IfcObject, or its subtypes, provides the specific information (as part of a type, or style, definition), that is common to all reflected instances of the declaring IfcObject, or its subtypes.

IsTypedBy SET [0:1] OF IfcRelDefinesByType FOR RelatedObjects

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.

IsDefinedBy SET [0:?] OF IfcRelDefinesByProperties FOR RelatedObjects

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.

IfcProduct (5)
6 ObjectPlacement OPTIONAL IfcObjectPlacement

This establishes the object coordinate system and 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 constrained (e.g. relative to grid axes, or to a linear positioning element). The type of placement is determined by the various subtypes of IfcObjectPlacement. An object placement must be provided if a representation is present.

7 Representation OPTIONAL IfcProductRepresentation

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.

ReferencedBy SET [0:?] OF IfcRelAssignsToProduct FOR RelatingProduct

Reference to the IfcRelAssignsToProduct relationship, by which other products, processes, controls, resources or actors (as subtypes of IfcObjectDefinition) can be related to this product.

PositionedRelativeTo SET [0:?] OF IfcRelPositions FOR RelatedProducts

No description available.

ReferencedInStructures SET [0:?] OF IfcRelReferencedInSpatialStructure FOR RelatedElements

No description available.

IfcElement (13)
8 Tag OPTIONAL IfcIdentifier

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.

FillsVoids SET [0:1] OF IfcRelFillsElement FOR RelatedBuildingElement

Reference to the IfcRelFillsElement Relationship that puts the element as a filling into the opening created within another element.

ConnectedTo SET [0:?] OF IfcRelConnectsElements FOR RelatingElement

Reference to the element connection relationship. The relationship then refers to the other element to which this element is connected to.

IsInterferedByElements SET [0:?] OF IfcRelInterferesElements FOR RelatedElement

Reference to the interference relationship to indicate the element that is interfered. The relationship, if provided, indicates that this element has an interference with one or many other elements.

InterferesElements SET [0:?] OF IfcRelInterferesElements FOR RelatingElement

Reference to the interference relationship to indicate the element that interferes. The relationship, if provided, indicates that this element has an interference with one or many other elements.

HasProjections SET [0:?] OF IfcRelProjectsElement FOR RelatingElement

Projection relationship that adds a feature (using a Boolean union) to the IfcBuildingElement.

HasOpenings SET [0:?] OF IfcRelVoidsElement FOR RelatingBuildingElement

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.

IsConnectionRealization SET [0:?] OF IfcRelConnectsWithRealizingElements FOR RealizingElements

Reference to the connection relationship with realizing element. The relationship, if provided, assigns this element as the realizing element to the connection, which provides the physical manifestation of the connection relationship.

ProvidesBoundaries SET [0:?] OF IfcRelSpaceBoundary FOR RelatedBuildingElement

Reference to space boundaries by virtue of the objectified relationship IfcRelSpaceBoundary. It defines the concept of an element bounding spaces.

ConnectedFrom SET [0:?] OF IfcRelConnectsElements FOR RelatedElement

Reference to the element connection relationship. The relationship then refers to the other element that is connected to this element.

ContainedInStructure SET [0:1] OF IfcRelContainedInSpatialStructure FOR RelatedElements

Containment relationship to the spatial structure element, to which the element is primarily associated. This containment relationship has to be hierarchical, i.e. an element may only be assigned directly to zero or one spatial structure.

HasCoverings SET [0:?] OF IfcRelCoversBldgElements FOR RelatingBuildingElement

Reference to IfcCovering by virtue of the objectified relationship IfcRelCoversBldgElement. It defines the concept of an element having coverings associated.

HasSurfaceFeatures SET [0:?] OF IfcRelAdheresToElement FOR RelatingElement

Reference to the IfcRelAdheresToElement relationship that adheres a IfcSurfaceFeature to an element. An element can incorporate zero-to-many surface features in one relationship.

Click to show 34 hidden inherited attributes Click to hide 34 inherited attributes
IfcMember (1)
9 PredefinedType OPTIONAL IfcMemberTypeEnum

Predefined generic type for a member that is specified in an enumeration. There may be a property set given for the predefined types.

Table 6.1.3.18.J

6.1.3.18.4 Formal propositions

Name Description
CorrectPredefinedType

Either the PredefinedType attribute is unset (e.g. because an IfcMemberType is associated), or the inherited attribute ObjectType shall be provided, if the PredefinedType is set to USERDEFINED.

NOT(EXISTS(PredefinedType)) OR
 (PredefinedType <> IfcMemberTypeEnum.USERDEFINED) OR
 ((PredefinedType = IfcMemberTypeEnum.USERDEFINED) AND EXISTS (SELF\IfcObject.ObjectType))
CorrectTypeAssigned

Either there is no member type object associated, i.e. the IsTypedBy inverse relationship is not provided, or the associated type object has to be of type IfcMemberType.

(SIZEOF(IsTypedBy) = 0) OR
  ('IFC4X3.IFCMEMBERTYPE' IN TYPEOF(SELF\IfcObject.IsTypedBy[1].RelatingType))
Table 6.1.3.18.K

6.1.3.18.5 Property sets

  • Pset_ConcreteElementGeneral
    • AssemblyPlace
    • CastingMethod
    • StructuralClass
    • StrengthClass
    • ExposureClass
    • ReinforcementVolumeRatio
    • ReinforcementAreaRatio
    • DimensionalAccuracyClass
    • ConstructionToleranceClass
    • ConcreteCover
    • ConcreteCoverAtMainBars
    • ConcreteCoverAtLinks
    • ReinforcementStrengthClass
  • Pset_Condition
    • AssessmentDate
    • AssessmentCondition
    • AssessmentDescription
    • AssessmentType
    • AssessmentMethod
    • LastAssessmentReport
    • NextAssessmentDate
    • AssessmentFrequency
  • Pset_ConstructionAdministration
    • ProcurementMethod
    • SpecificationSectionNumber
    • SubmittalIdentifer
  • Pset_ConstructionOccurance
    • InstallationDate
    • ModelNumber
    • TagNumber
    • AssetIdentifier
  • Pset_ElementKinematics
    • CyclicPath
    • CyclicRange
    • LinearPath
    • LinearRange
    • MaximumAngularVelocity
    • MaximumConstantSpeed
    • MinimumTime
  • Pset_ElementKinematics
    • CyclicPath
    • CyclicRange
    • LinearPath
    • LinearRange
    • MaximumAngularVelocity
    • MaximumConstantSpeed
    • MinimumTime
  • Pset_EnvironmentalCondition
    • ReferenceAirRelativeHumidity
    • ReferenceEnvironmentTemperature
    • MaximumAtmosphericPressure
    • StorageTemperatureRange
    • MaximumWindSpeed
    • OperationalTemperatureRange
    • MaximumRainIntensity
    • SaltMistLevel
    • SeismicResistance
    • SmokeLevel
    • MaximumSolarRadiation
  • Pset_EnvironmentalImpactIndicators
    • Reference
    • FunctionalUnitReference
    • IndicatorsUnit
    • LifeCyclePhase
    • ExpectedServiceLife
    • TotalPrimaryEnergyConsumptionPerUnit
    • WaterConsumptionPerUnit
    • HazardousWastePerUnit
    • NonHazardousWastePerUnit
    • ClimateChangePerUnit
    • AtmosphericAcidificationPerUnit
    • RenewableEnergyConsumptionPerUnit
    • NonRenewableEnergyConsumptionPerUnit
    • ResourceDepletionPerUnit
    • InertWastePerUnit
    • RadioactiveWastePerUnit
    • StratosphericOzoneLayerDestructionPerUnit
    • PhotochemicalOzoneFormationPerUnit
    • EutrophicationPerUnit
  • Pset_EnvironmentalImpactValues
    • TotalPrimaryEnergyConsumption
    • WaterConsumption
    • HazardousWaste
    • NonHazardousWaste
    • ClimateChange
    • AtmosphericAcidification
    • RenewableEnergyConsumption
    • NonRenewableEnergyConsumption
    • ResourceDepletion
    • InertWaste
    • RadioactiveWaste
    • StratosphericOzoneLayerDestruction
    • PhotochemicalOzoneFormation
    • Eutrophication
    • LeadInTime
    • Duration
    • LeadOutTime
  • Pset_InstallationOccurrence
    • InstallationDate
    • AcceptanceDate
    • PutIntoOperationDate
  • Pset_MaintenanceStrategy
    • AssetCriticality
    • AssetFrailty
    • AssetPriority
    • MonitoringType
    • AccidentResponse
  • Pset_MaintenanceTriggerCondition
    • ConditionTargetPerformance
    • ConditionMaintenanceLevel
    • ConditionReplacementLevel
    • ConditionDisposalLevel
  • Pset_MaintenanceTriggerDuration
    • DurationTargetPerformance
    • DurationMaintenanceLevel
    • DurationReplacementLevel
    • DurationDisposalLevel
  • Pset_MaintenanceTriggerPerformance
    • TargetPerformance
    • PerformanceMaintenanceLevel
    • ReplacementLevel
    • DisposalLevel
  • Pset_ManufacturerOccurrence
    • AcquisitionDate
    • BarCode
    • SerialNumber
    • BatchReference
    • AssemblyPlace
    • ManufacturingDate
  • Pset_ManufacturerTypeInformation
    • GlobalTradeItemNumber
    • ArticleNumber
    • ModelReference
    • ModelLabel
    • Manufacturer
    • ProductionYear
    • AssemblyPlace
    • OperationalDocument
    • SafetyDocument
    • PerformanceCertificate
  • Pset_MemberCommon
    • Reference
    • Status
    • Span
    • Slope
    • Roll
    • IsExternal
    • ThermalTransmittance
    • LoadBearing
    • FireRating
  • Pset_MemberTypeAnchoringBar BRACE
    • MechanicalStressType
    • HasLightningRod
  • Pset_MemberTypeCatenaryStay STAY_CABLE
    • AssemblyInstruction
    • NominalLength
    • CatenaryStayType
    • NominalHeight
  • Pset_MemberTypeOCSRigidSupport MEMBER
    • AssemblyInstruction
    • ContactWireStagger
  • Pset_MemberTypePost POST
    • NominalHeight
    • ConicityRatio
    • LoadBearingCapacity
    • WindLoadRating
    • TorsionalStrength
    • BendingStrength
  • Pset_MemberTypeTieBar TIEBAR
    • IsTemporaryInstallation
  • Pset_PrecastConcreteElementFabrication
    • TypeDesignation
    • ProductionLotId
    • SerialNumber
    • PieceMark
    • AsBuiltLocationNumber
    • ActualProductionDate
    • ActualErectionDate
  • Pset_PrecastConcreteElementGeneral
    • TypeDesignation
    • CornerChamfer
    • ManufacturingToleranceClass
    • FormStrippingStrength
    • LiftingStrength
    • ReleaseStrength
    • MinimumAllowableSupportLength
    • InitialTension
    • TendonRelaxation
    • TransportationStrength
    • SupportDuringTransportDescription
    • SupportDuringTransportDocReference
    • HollowCorePlugging
    • CamberAtMidspan
    • BatterAtStart
    • BatterAtEnd
    • Twisting
    • Shortening
    • PieceMark
    • DesignLocationNumber
  • Pset_RepairOccurrence
    • RepairContent
    • RepairDate
    • MeanTimeToRepair
  • Pset_Risk
    • RiskName
    • RiskType
    • NatureOfRisk
    • RiskAssessmentMethodology
    • UnmitigatedRiskLikelihood
    • UnmitigatedRiskConsequence
    • UnmitigatedRiskSignificance
    • MitigationPlanned
    • MitigatedRiskLikelihood
    • MitigatedRiskConsequence
    • MitigatedRiskSignificance
    • MitigationProposed
    • AssociatedProduct
    • AssociatedActivity
    • AssociatedLocation
  • Pset_ServiceLife
    • ServiceLifeDuration
    • MeanTimeBetweenFailure
  • Pset_Tolerance
    • ToleranceDescription
    • ToleranceBasis
    • OverallTolerance
    • HorizontalTolerance
    • OrthogonalTolerance
    • VerticalTolerance
    • PlanarFlatness
    • HorizontalFlatness
    • ElevationalFlatness
    • SideFlatness
    • OverallOrthogonality
    • HorizontalOrthogonality
    • OrthogonalOrthogonality
    • VerticalOrthogonality
    • OverallStraightness
    • HorizontalStraightness
    • OrthogonalStraightness
    • VerticalStraightness
  • Pset_Uncertainty
    • UncertaintyBasis
    • UncertaintyDescription
    • HorizontalUncertainty
    • LinearUncertainty
    • OrthogonalUncertainty
    • VerticalUncertainty
  • Pset_Warranty
    • WarrantyIdentifier
    • WarrantyStartDate
    • IsExtendedWarranty
    • WarrantyPeriod
    • WarrantyContent
    • PointOfContact
    • Exclusions
  • Qto_BodyGeometryValidation
    • GrossSurfaceArea
    • NetSurfaceArea
    • GrossVolume
    • NetVolume
    • SurfaceGenusBeforeFeatures
    • SurfaceGenusAfterFeatures
  • Qto_MemberBaseQuantities
    • Length
    • CrossSectionArea
    • OuterSurfaceArea
    • GrossSurfaceArea
    • NetSurfaceArea
    • GrossVolume
    • NetVolume
    • GrossWeight
    • NetWeight

6.1.3.18.6 Concept usage

Concept Usage Description
IfcRoot (2)
Revision Control General

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

Software Identity General

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

IfcObjectDefinition (9)
Aggregation General

No description available.

Approval Association General

No description available.

Classification Association General

Any object occurrence or object type can have a reference to a specific classification reference, i.e. to a particular facet within a classification system.

Constraint Association General

No description available.

Document Association General

No description available.

Library Association General

No description available.

Material Association General

No description available.

Material Single General

No description available.

Nesting General

No description available.

IfcObject (5)
Assignment to Group General

No description available.

Object Predefined Type General

No description available.

Object Typing General

Any object occurrence can be typed by being assigned to a common object type utilizing this concept. A particular rule, restricting the applicable subtypes of IfcTypeObject that can be assigned, is introduced by overriding this concept at the level of subtypes of IfcObject.

This concept can be applied to the following resources:

Object User Identity General

An attribute Name and optionally Description can be used for all subypes of IfcObject. For those subtypes, that have an object type definition, such as ifcBeam - IfcBeamType, the common Name and optionally Description is associated with the object type.

Property Sets with Override General

Any object occurrence can hold property sets, either directly at the object occurrence as element specific property sets, or at the object type, as type property sets. In this case, the properties that are provided to the object occurrence are the combinations of element specific and type properties. In case, that the same property (within the same property set, is defined both, in occurrence and type properties, the property value of the occurrence property overrides the property value of the type property.

IfcProduct (17)
Body Geometry General

The body or solid model geometric representation of an IfcProduct is typically defined using a Tessellation or Brep. Subtypes may provide recommendations on other representation types that may be used. The following attribute values for the IfcShapeRepresentation holding this geometric representation shall be used:

Box Geometry General

No description available.

CoG Geometry General

No description available.

Mapped Geometry General

No description available.

Product Geometric Representation General

The geometric representation of any IfcProduct is provided by the IfcProductDefinitionShape allowing multiple geometric representations. It uses the Product Placement concept utilizing IfcLocalPlacement to establish an object coordinate system, within all geometric representations are founded.

Product Geometry Colour General

No description available.

Product Geometry Layer General

No description available.

Product Local Placement General

No description available.

Product Relative Positioning General

If the IfcProduct Product Placement is placed relative to an IfcPositioningElement this relationship covers the information on which IfcPositioningElement positions the IfcProduct.

Product Span Positioning General

No description available.

Product Topology Representation General

No description available.

Property Sets for Objects General

This concept can be applied to the following resources:

Quantity Sets General

This concept can be applied to the following resources:

Reference Geometry General

No description available.

Reference SweptSolid Geometry General

No description available.

Reference SweptSolid PolyCurve Geometry General

No description available.

Reference Tessellation Geometry General

No description available.

IfcElement (45)
Body AdvancedBrep Geometry General

An IfcElement (so far no further constraints are defined at the level of its subtypes or by view definitions) may be represented as a single or multiple boundary representation models, which include advanced surfaces, usually refered to as NURBS surfaces. The 'AdvancedBrep' representation allows for the representation of complex free-form element shape.

Body AdvancedSwept Directrix Geometry General

No description available.

Body AdvancedSwept DiskSolid PolyCurve Geometry General

No description available.

Body AdvancedSwept Tapered Geometry General

No description available.

Body AdvancedSweptSolid Geometry General

No description available.

Body Brep Geometry General

Any IfcElement (so far no further constraints are defined at the level of its subtypes) may be represented as a single or multiple Boundary Representation models (which are restricted to be faceted Brep's with or without voids). The Brep representation allows for the representation of complex element shape.

Brep representation
Figure 6.1.3.18.A — Building element body boundary representation
Body CSG Geometry General

Any IfcElement (so far no further constraints are defined at the level of its subtypes) may be represented a CSG primitive or CSG tree. The CSG representation allows for the representation of complex element shape.

Body Clipping Geometry General

No description available.

Body SectionedSolidHorizontal General

No description available.

Body SurfaceModel Geometry General

Any IfcElement (so far no further constraints are defined at the level of its subtypes) may be represented as a single or multiple surface models, based on either shell or face based surface models. It may also include tessellated models.

surface model
Figure 6.1.3.18.B — Element surface model representation
Body SurfaceOrSolidModel Geometry General

Any IfcElement (so far no further constraints are defined at the level of its subtypes) may be represented as a mixed representation, including surface and solid models.

Body SweptSolid Composite Geometry General

No description available.

Body SweptSolid CompositeCurve Geometry General

No description available.

Body SweptSolid Geometry General

No description available.

Body SweptSolid ParameterizedProfile Geometry General

No description available.

Body SweptSolid PolyCurve Geometry General

No description available.

Body Tessellation Geometry Reference View

Any IfcElement (so far no further constraints are defined at the level of its subtypes) may be represented as a single or multiple tessellated surface models, in particular triangulated surface models.

Box Geometry General
bounding box
Figure 6.1.3.18.C — Building element box representation
CoG Geometry General

The 'CoG', Center of Gravity, shape representation is used as a means to verify the correct import by comparing the CoG of the imported geometry with the explicily provided CoG created during export.

Element Covering General

No description available.

Element Interference General

No description available.

Element Nesting General

A host element can nest connected components. This should be used when there is a specific position or form factor to attach specific elements.

Element Occurrence Attributes General

No description available.

Element Openings General

No description available.

Element Projecting General

No description available.

Element Voiding General

No description available.

Element Voiding Features General

No description available.

FootPrint Annotation Geometry General

No description available.

FootPrint GeomSet PolyCurve Geometry General

No description available.

FootPrint Geometry General

No description available.

Lighting Geometry General

No description available.

Mapped Geometry General

Any IfcElement (so far no further constraints are defined at the level of its subtypes) may be represented using the 'MappedRepresentation'. This shall be supported as it allows for reusing the geometry definition of a type at all occurrences of the same type. The results are more compact data sets.

The same constraints, as given for 'SurfaceOrSolidModel', 'SurfaceModel', 'Tessellation', 'Brep', and 'AdvancedBrep' geometric representation, shall apply to the IfcRepresentationMap.

Object Typing General

This concept can be applied to the following resources:

Product Grid Placement General

No description available.

Product Linear Placement General

Product placement with a Product Linear Placement template. It defines the local coordinate system based on the curve which is referenced by IfcLinearPlacement.RelativePlacement which is an IfcAxis2PlacementLinear.Location using an IfcPointByDistanceExpression.BasisCurve. The local coordinate system is based on the tangent of the curve at Location, its normal in the global Z plane and the cross product of the aforementioned vectors.

Product Local Placement General

The object placement for any subtype of IfcElement is defined by the IfcObjectPlacement, either IfcLocalPlacement or IfcGridPlacement, which defines the local object coordinate system that is referenced by all geometric representations of that IfcElement.

Profile 3D Geometry General

No description available.

Profile Geometry General

No description available.

Property Sets for Objects General

This concept can be applied to the following resources:

Spatial Containment General

This concept can be applied to the following resources:

Surface 3D Geometry General

No description available.

Surface Feature Adherence General

No description available.

Surface Geometry General

No description available.

Surface Sectioned Geometry General

No description available.

Surface Tessellation Geometry General

No description available.

IfcBuiltElement (3)
Object Typing General

This concept can be applied to the following resources:

Product Assignment General

This concept can be applied to the following resources:

  • IfcTask - A task for operating on the member.
Surface 3D Geometry General

Some IfcBuildingElement may be represented by an surface as an abstract geometric representation. See each subtype for specific guidance.

Click to show 81 hidden inherited concepts Click to hide 81 inherited concepts
IfcMember (11)
Axis 3D Geometry General

The axis representation can be used to represent the fundamental orientation and extents of a member's body.

If an IfcMaterialProfileSetUsage is used, the axis representation is used to locate the profile. In addition:

As shown in Figure 6.1.3.18.D, the axis representation can be used to represent the system length of a member that may extend past the body length of the member.

Axis
Figure 6.1.3.18.D — Member axis representation

As shown in Figure 6.1.3.18.H, the axis representation must be positioned at the IfcMaterialProfileSetUsage.CardinalPoint, and parallel to the IfcExtrudedAreaSolid.ExtrudedDirection. This offset between the axis line and the IfcExtrudedAreaSolid.Position must correlate with the chosen IfcMaterialProfileSetUsage.CardinalPoint.

Axis
Figure 6.1.3.18.H — Member axis cardinal point
Body AdvancedSweptSolid Geometry General
Body Clipping Geometry General

Figure 6.1.3.18.F illustrates a 'Clipping' geometric representation with use of IfcBooleanClippingResult between an IfcExtrudedAreaSolid and an IfcHalfSpaceSolid to create a clipped body.

clipped member
Figure 6.1.3.18.F — Member clipping

When an IfcMaterialProfileSetUsage is applied, Figure 6.1.3.18.G illustrates an advanced geometric representation with use of IfcBooleanClippingResult between an IfcExtrudedAreaSolid and an IfcHalfSpaceSolid to create a clipped body, with cardinal point applied as 4 (mid-depth left).

clipped beam
Figure 6.1.3.18.G — Member body clipping
Body SweptSolid Geometry General

When an (IfcMaterialProfileSetUsage) is assigned to the IfcMember:

  • For all single profiles, the IfcParameterizedProfileDef.Position shall be NIL, or having Location = 0.,0. and RefDirection = 1.,0.
  • The extrusion shall be perpendicular to the profile direction.
  • The y-axis of the profile, as determined by IfcSweptAreaSolid.Position.P[2] shall point to the Z-Axis. It indicates the "role" of the column, a role=0° means y-axis of profile = Z-axis of reference coordinate system. In the exception of a vertical member, the y-axis shall point to the Y-axis.

Figure 6.1.3.18.H illustrates a 'SweptSolid' geometric representation with cardinal point applied as 1 (bottom left).

If parametric profiles are used, the parameters may be interpreted to be the dimensions of the beam:

standard member
Figure 6.1.3.18.H — Member body extrusion
Material Profile Set Usage General

Figure 211 illustrates assignment of IfcMaterialProfileSetUsage and IfcMaterialProfileSet to the IfcMemberType and the IfcMember occurrence. Both the IfcMaterialProfileSet and IfcProfileDef is shared between all occurrences.

Material profile set and usage
Figure 6.1.3.18.E — Member profile usage

Figure 6.1.3.18.I illustrates assignment of a composite profile by using IfcCompositeProfileDef for geometric representation and several IfcMaterialProfile entities within the IfcMaterialProfileSet.

Material profile set and usage
Figure 6.1.3.18.I — Member composite profiles
Material Set General

This concept can be applied to the following resources:

  • LoadBearing
Object Typing General

This concept can be applied to the following resources:

Product Assignment General

This concept can be applied to the following resources:

Property Sets for Objects General

This concept can be applied to the following resources:

Quantity Sets General

This concept can be applied to the following resources:

Spatial Containment General

The IfcMember, as any subtype of IfcBuildingElement, may participate alternatively in one of the two different containment relationships:

  • the Spatial Containment (defined here), or
  • the Element Composition.
Table 6.1.3.18.L

6.1.3.18.7 Formal representation

ENTITY IfcMember
 SUBTYPE OF (IfcBuiltElement);
	PredefinedType : OPTIONAL IfcMemberTypeEnum;
 WHERE
	CorrectPredefinedType : NOT(EXISTS(PredefinedType)) OR
 (PredefinedType <> IfcMemberTypeEnum.USERDEFINED) OR
 ((PredefinedType = IfcMemberTypeEnum.USERDEFINED) AND EXISTS (SELF\IfcObject.ObjectType));
	CorrectTypeAssigned : (SIZEOF(IsTypedBy) = 0) OR
  ('IFC4X3.IFCMEMBERTYPE' IN TYPEOF(SELF\IfcObject.IsTypedBy[1].RelatingType));
END_ENTITY;

6.1.3.18.8 References

6.1.3.18.9 Changelog

  • attributes, PredefinedType
  • where_rules, CorrectPredefinedType
  • where_rules, CorrectTypeAssigned