IFC 4.3.x development

7.11.3.2 IfcRelConnectsStructuralMember

7.11.3.2.1 Semantic definitions at the entity

The entity IfcRelConnectsStructuralMember defines all needed properties describing the connection between structural members and structural connection objects (nodes or supports).

HISTORY  New entity in IFC2x2.

Use Definition

Point Connection
Instances of the entity IfcRelConnectsStructuralMember shall be used to describe a connection between an instance of IfcStructuralPointConnection and either an instance of IfcStructuralCurveMember or IfcStructuralSurfaceMember. The RelatedStructuralConnection for point connections has to be of type IfcStructuralPointConnection.

Curve Connection
Instances of the entity IfcRelConnectsStructuralMember shall be used to describe a connection between an instance of IfcStructuralCurveConnection and an instance of either IfcStructuralCurveMember or IfcStructuralSurfaceMember. The RelatedStructuralConnection for curve connections has to be of type IfcStructuralCurveConnection.

Surface Connection
Instances of the entity IfcRelConnectsStructuralMember shall be used to describe a connection between an instance of IfcStructuralSurfaceConnection and an instance of IfcStructuralSurfaceMember. The RelatedStructuralConnection for curve connections has to be of type IfcStructuralSurfaceConnection.

Coordinate System for Applied Conditions
All values defined by AppliedCondition or AdditionalConditions are given within the coordinate system provided by ConditionCoordinateSystem, which is defined relative to the local coordinate system of the structural member. If the ConditionCoordinateSystem is not defined, the local coordinate system of the structural member is used instead.

Supported Length
Optionally a supported length can be given, which specifies the length (or width) of the physical connection along a curve connection.

Figure 1 illustrates the appropriate definition of support lengths.

supported length

Figure 1 — Structural member support lengths

7.11.3.2.1 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.

7.11.3.2.2 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

7.11.3.2.3 Definitions applying to General Usage

7.11.3.2.3.1 Identity

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

7.11.3.2.3.2 Revision Control

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

7.11.3.2.4 Formal representations

ENTITY IfcRelConnectsStructuralMember
 SUPERTYPE OF (ONEOF
	(IfcRelConnectsWithEccentricity))
 SUBTYPE OF (IfcRelConnects);
	RelatingStructuralMember : IfcStructuralMember;
	RelatedStructuralConnection : IfcStructuralConnection;
	AppliedCondition : OPTIONAL IfcBoundaryCondition;
	AdditionalConditions : OPTIONAL IfcStructuralConnectionCondition;
	SupportedLength : OPTIONAL IfcLengthMeasure;
	ConditionCoordinateSystem : OPTIONAL IfcAxis2Placement3D;
END_ENTITY;