IFC 4.3.x development

7.11.3.3 IfcRelConnectsWithEccentricity

7.11.3.3.1 Semantic definitions at the entity

The entity IfcRelConnectsWithEccentricity adds the definition of eccentricity to the connection between a structural member and a structural connection (representing either a node or support).

NOTE  Another eccentricity model is available independently of eccentric connection specification: The section profile of a curve member may be inserted eccentrically with respect to the member's reference curve, see definitions at IfcStructuralCurveMember. Whether one or the other or both eccentricity models may be used is subject to information requirements and local agreements.

HISTORY  New entity in IFC2x3.

IFC4 CHANGE  Use definitions changed to always require two topology items.

Use Definition

Point Connection
ConnectionConstraint shall be of type IfcConnectionPointGeometry and shall refer to two instances of IfcVertexPoint.

Curve Connection
ConnectionConstraint shall be of type IfcConnectionCurveGeometry and shall refer to two instances of IfcEdge or subtypes.

Surface Connection
ConnectionConstraint shall be of type IfcConnectionSurfaceGeometry and shall refer to two instances of IfcFaceSurface.

7.11.3.3.1 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
IfcRelConnectsStructuralMember
5RelatingStructuralMember IfcStructuralMember Reference to an instance of IfcStructuralMember (or its subclasses) which is connected to the specified structural connection.
6RelatedStructuralConnectionIfcStructuralConnection Reference to an instance of IfcStructuralConnection (or its subclasses) which is connected to the specified structural member.
7AppliedCondition OPTIONAL IfcBoundaryCondition Conditions which define the connections properties. Connection conditions are often called "release" but are not only used to define mechanisms like hinges but also rigid, elastic, and other conditions.
8AdditionalConditions OPTIONAL IfcStructuralConnectionConditionDescribes additional connection properties.
9SupportedLength OPTIONAL IfcLengthMeasure Defines the 'supported length' of this structural connection. See Fig. for more detail.
10ConditionCoordinateSystem OPTIONAL IfcAxis2Placement3D Defines a coordinate system used for the description of the connection properties in ConnectionCondition relative to the local coordinate system of RelatingStructuralMember. If left unspecified, the placement IfcAxis2Placement3D((x,y,z), ?, ?) is implied with x,y,z being the local member coordinates where the connection is made and the default axes directions being in parallel with the local axes of RelatingStructuralMember.
IfcRelConnectsWithEccentricity
11ConnectionConstraint IfcConnectionGeometry The connection constraint explicitly states the eccentricity between a structural member and a structural connection by means of two topological objects (vertex and vertex, or edge and edge, or face and face).

7.11.3.3.2 Entity inheritance

dot_inheritance IfcRelConnectsWithEccentricity IfcRelConnectsWithEccentricity IfcRelConnectsStructuralMember IfcRelConnectsStructuralMember IfcRelConnectsWithEccentricity->IfcRelConnectsStructuralMember IfcRelConnects IfcRelConnects IfcRelConnectsStructuralMember->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

7.11.3.3.3 Definitions applying to General Usage

7.11.3.3.3.1 Identity

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

7.11.3.3.3.2 Revision Control

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

7.11.3.3.4 Formal representations

ENTITY IfcRelConnectsWithEccentricity
 SUBTYPE OF (IfcRelConnectsStructuralMember);
	ConnectionConstraint : IfcConnectionGeometry;
END_ENTITY;