6.1.3.20 IfcMemberStandardCase

Stab / Stabträger - Standard
Membre standard

The standard member, IfcMemberStandardCase, defines a member with certain constraints for the provision of material usage, parameters and with certain constraints for the geometric representation. The IfcMemberStandardCase handles all cases of members, that:

NOTE  View definitions and implementer agreements may further constrain the applicable geometry types, such as by excluding tapering from an IfcMemberStandardCase implementation.
HISTORY  New entity in IFC4.

Common Use Definitions

The following concepts are inherited at supertypes:

 Instance diagram

Object Typing

The Object Typing concept applies to this entity as shown in Table 132.
Type
IfcMemberType

Table 132 — IfcMemberStandardCase Object Typing

The IfcMemberStandardCase defines in addition that the IfcMemberType should have a unique IfcMaterialProfileSet, that is referenced by the IfcMaterialProfileSetUsage assigned to all occurrences of this IfcMemberType.



Material Profile Set Usage

The Material Profile Set Usage concept applies to this entity.

Figure 190 illustrates assignment of IfcMaterialProfileSetUsage and IfcMaterialProfileSet to the IfcMemberStandardCase as the member occurrence and to the IfcMemberType. The same IfcMaterialProfileSet shall be shared by many occurrences of IfcMaterialProfileSetUsage. This relationship shall be consistent to the relationship between the IfcMemberType and the IfcMemberStandardCase.

Material profile set and usage

Figure 190 — Member profile usage

Figure 191 illustrates assignment of a composite profile by using IfcCompositeProfile for geometric representation and several IfcMaterialProfile's within the IfcMaterialProfileSet. The number of IfcMaterialProfile's within the IfcMaterialProfileSet is restricted to maximal 2 and requires the use of IfcExtrudedAreaSolidTapered, or IfcRevolvedAreaSolidTapered for the correct 'Body' shape representation.

Material profile set and usage

Figure 191 — Member composite profiles

The material of the IfcMemberStandardCase is defined by IfcMaterialProfileSetUsage and attached by the IfcRelAssociatesMaterial.RelatingMaterial. It is accessible by the inverse HasAssociations relationship. Composite profile members can be represented by refering to several IfcMaterialProfile's within the IfcMaterialProfileSet that is referenced from the IfcMaterialProfileSetUsage.

Material information can also be given at the IfcMemberType, defining the common attribute data for all occurrences of the same type. It is then accessible by the inverse IsDefinedBy relationship pointing to IfcMemberType.HasAssociations and via IfcRelAssociatesMaterial.RelatingMaterial. See Type Use Definition for additional agreements for standard members.



Product Placement

The Product Placement concept applies to this entity as shown in Table 133.
TypeRelativeDescription
IfcLocalPlacementIfcLocalPlacementRelative placement according to position and rotation relative to container.
IfcLocalPlacement Absolute placement according to position and rotation of world coordinate system.
IfcGridPlacement Placement according to grid intersection.

Table 133 — IfcMemberStandardCase Product Placement

The following restriction is imposed:



Axis 3D Geometry

The Axis 3D Geometry concept applies to this entity as shown in Table 134.
IdentifierTypeItemsDescription
AxisCurve3DIfcBoundedCurveThree-dimensional reference curve for the member.

Table 134 — IfcMemberStandardCase Axis 3D Geometry

The following additional constraints apply to the 'Axis' representation, if the 'Body' shape representation has the RepresentationType : 'SweptSolid':

 

Axis
EXAMPLE  As shown in Figure 101, the axis representation can be used to represent the system length of a member that may extent the body length of the member.

Figure 192 — Member axis representation

 
Axis
EXAMPLE  As shown in Figure 102, the axis representation shall be used to represent the cardinal point as the offset between the 'Axis' and the extrusion path of the member. The extrusion path is provided as IfcExtrudedAreaSolid.ExtrudedDirection and should be parallel to the 'Axis'. It has to be guaranteed that the value provided by IfcMaterialProfileSetUsage.CardinalPoint is consistent to the IfcExtrudedAreaSolid.Position.

Figure 193 — Member axis cardinal point

 


Body SweptSolid Geometry

The Body SweptSolid Geometry concept applies to this entity.

The following additional constraints apply to the 'SweptSolid' representation:

Figure 194 illustrates a 'SweptSolid' geometric representation with cardinal point applied as 1 (bottom left).

The following interpretation of dimension parameter applies for rectangular members:

The following interpretation of dimension parameter applies for circular members:

standard member

Figure 194 — Member body extrusion



Body AdvancedSweptSolid Geometry

The Body AdvancedSweptSolid Geometry concept applies to this entity.

The following additional constraints apply to the 'AdvancedSweptSolid' representation type:



Body Clipping Geometry

The Body Clipping Geometry concept applies to this entity.

The following constraints apply to the advanced representation:

Figure 195 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 195 — Member body clipping




XSD Specification:

 <xs:element name="IfcMemberStandardCase" type="ifc:IfcMemberStandardCase" substitutionGroup="ifc:IfcMember" nillable="true"/>
 <xs:complexType name="IfcMemberStandardCase">
  <xs:complexContent>
   <xs:extension base="ifc:IfcMember"/>
  </xs:complexContent>
 </xs:complexType>

EXPRESS Specification:

ENTITY IfcMemberStandardCase
SUBTYPE OF IfcMember;
WHERE
HasMaterialProfileSetUsage : SIZEOF (QUERY(temp <* USEDIN(SELF, 'IFCKERNEL.IFCRELASSOCIATES.RELATEDOBJECTS') | ('IFCPRODUCTEXTENSION.IFCRELASSOCIATESMATERIAL' IN TYPEOF(temp)) AND ('IFCMATERIALRESOURCE.IFCMATERIALPROFILESETUSAGE' IN TYPEOF(temp.RelatingMaterial)) )) = 1;
END_ENTITY;

Link to EXPRESS-G diagram EXPRESS-G diagram

Formal Propositions:

HasMaterialProfileSetUsage : A valid instance of IfcMemberStandardCase relies on the provision of an IfcMaterialProfileSetUsage.

Inheritance Graph:

ENTITY IfcMemberStandardCase
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 IfcBuildingElement
INVERSE
HasCoverings : SET OF IfcRelCoversBldgElements FOR RelatingBuildingElement;
ENTITY IfcMember
PredefinedType : OPTIONAL IfcMemberTypeEnum;
ENTITY IfcMemberStandardCase
END_ENTITY;

Link to this page  Link to this page