IfcTendon

Definition from IAI: A steel element such as a wire, cable, bar, rod, or strand used to impart prestress to concrete when the element is tensioned.

> HISTORY New entity in IFC Release 2x2

Geometry Use Definitions:

The geometric representation of IfcTendon is given by the IfcProductDefinitionShape, allowing multiple geometric representations. Included are:

Local Placement
The use of local placement is defined at the supertype IfcBuildingElementComponent.

Standard Geometric Representation using Swept Solid Representation
The standard geometric representation of IfcTendon is defined using the swept solid representation. The RepresentationType attribute of IfcShapeRepresentation should have the value 'SweptSolid'. The solid is formed from a cross section approximated as a circular disk swept along any arbitrary curve. Given this, the following constraints apply to the standard representation:

- Solid: IfcSweptDiskSolid introduced in IFC Release 2x2 shall be supported.
- Profile: The circular disk cross section approximation is defined by the Radius attribute of IfcSweptDiskSolid.
- Extrusion: The extrusion along any arbitrary curve is defined by the Directrix attribute of IfcSweptDiskSolid.

Simplified Geometric Representation
Simplified geometric representations may be used based on local agreements.

EXPRESS specification:

ENTITY IfcTendon
SUBTYPE OF ( | IfcReinforcingElement);
PredefinedType | : | IfcTendonTypeEnum;
NominalDiameter | : | IfcPositiveLengthMeasure;
CrossSectionArea | : | IfcAreaMeasure;
TensionForce | : | OPTIONAL IfcForceMeasure;
PreStress | : | OPTIONAL IfcPressureMeasure;
FrictionCoefficient | : | OPTIONAL IfcNormalisedRatioMeasure;
AnchorageSlip | : | OPTIONAL IfcPositiveLengthMeasure;
MinCurvatureRadius | : | OPTIONAL IfcPositiveLengthMeasure;
WHERE
WR1 | : | (PredefinedType <> IfcTendonTypeEnum.USERDEFINED) OR ((PredefinedType = IfcTendonTypeEnum.USERDEFINED) AND EXISTS(SELF\IfcObject.ObjectType)) ;
END_ENTITY;

Attribute definitions:

PredefinedType | : | Predefined generic types for a tendon.
NominalDiameter | : | The nominal diameter defining the cross-section size of the tendon.
CrossSectionArea | : | The effective cross-section area of the tendon.
TensionForce | : | The maximum allowed tension force that can be applied on the tendon.
PreStress | : | The prestress to be applied on the tendon.
FrictionCoefficient | : | The friction coefficient for the bond between the tendon and the surrounding concrete.
AnchorageSlip | : | The deformation of an anchor or slippage of tendons when the prestressing device is released.
MinCurvatureRadius | : | The smallest curvature radius calculated on the whole effective length of the tendon where the tension properties are still valid.

Formal Propositions:

WR1 | : | The attribute ObjectType shall be given, if the predefined type is set to USERDEFINED.

Inheritance graph

ENTITY IfcTendon;
ENTITY IfcRoot;
GlobalId | : | IfcGloballyUniqueId;
OwnerHistory | : | IfcOwnerHistory;
Name | : | OPTIONAL IfcLabel;
Description | : | OPTIONAL IfcText;
ENTITY IfcObjectDefinition;
INVERSE
HasAssignments | : | SET OF IfcRelAssigns FOR RelatedObjects;
IsDecomposedBy | : | SET OF IfcRelDecomposes FOR RelatingObject;
Decomposes | : | SET [0:1] OF IfcRelDecomposes FOR RelatedObjects;
HasAssociations | : | SET OF IfcRelAssociates FOR RelatedObjects;
ENTITY IfcObject;
ObjectType | : | OPTIONAL IfcLabel;
INVERSE
IsDefinedBy | : | SET OF IfcRelDefines FOR RelatedObjects;
ENTITY IfcProduct;
ObjectPlacement | : | OPTIONAL IfcObjectPlacement;
Representation | : | OPTIONAL IfcProductRepresentation;
INVERSE
ReferencedBy | : | SET OF IfcRelAssignsToProduct FOR RelatingProduct;
ENTITY IfcElement;
Tag | : | OPTIONAL IfcIdentifier;
INVERSE
HasStructuralMember | : | SET OF IfcRelConnectsStructuralElement FOR RelatingElement;
FillsVoids | : | SET [0:1] OF IfcRelFillsElement FOR RelatedBuildingElement;
ConnectedTo | : | SET OF IfcRelConnectsElements FOR RelatingElement;
HasCoverings | : | SET OF IfcRelCoversBldgElements FOR RelatingBuildingElement;
HasProjections | : | SET OF IfcRelProjectsElement FOR RelatingElement;
ReferencedInStructures | : | SET OF IfcRelReferencedInSpatialStructure FOR RelatedElements;
HasPorts | : | SET OF IfcRelConnectsPortToElement FOR RelatedElement;
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;
ENTITY IfcBuildingElementComponent;
ENTITY IfcReinforcingElement;
SteelGrade | : | OPTIONAL IfcLabel;
ENTITY IfcTendon;
PredefinedType | : | IfcTendonTypeEnum;
NominalDiameter | : | IfcPositiveLengthMeasure;
CrossSectionArea | : | IfcAreaMeasure;
TensionForce | : | OPTIONAL IfcForceMeasure;
PreStress | : | OPTIONAL IfcPressureMeasure;
FrictionCoefficient | : | OPTIONAL IfcNormalisedRatioMeasure;
AnchorageSlip | : | OPTIONAL IfcPositiveLengthMeasure;
MinCurvatureRadius | : | OPTIONAL IfcPositiveLengthMeasure;
END_ENTITY;