IfcStructuralPointReaction

Definition from IAI: Instances of the entity IfcStructuralPointReaction are used to define point reactions. IfcStructuralPointReaction inherits all needed attributes from its superclass IfcStructuralReaction.

The structural load, defining the point reaction is given by the attribute AppliedLoad at the supertype IfcStructuralActivity. The coordinate system, in which the AppliedLoad is defined is given by the attribute ObjectPlacement at the supertype IfcProduct.

> HISTORY: New entity in Release IFC2x Edition 2.

Topology Use Definition

Instances of IfcStructuralPointReaction shall have a topology representation. It includes a placement and a product representation. The IfcProductRepresentation shall be given by an item of Representations being of type "IfcTopologyRepresentation".

Placement

The placement for IfcStructuralPointReaction is determined at its supertype IfcProduct. It is defined by the optional IfcObjectPlacement, referenced by ObjectPlacement at IfcProduct, which establishes, if given, the object coordinate system that is referenced by the applied load.

- Ifc the ObjectPlacement attribute is omitted, then all topological representations are given directly in world coordinates.
- Ifc the ObjectPlacement attribute is provided, then it establishes an object coordinate system for all topological representations which are given object coordinates.
  - If the PlacementRelTo relationship of IfcLocalPlacement is omitted, the object coordinate system is established within the world coordinate system.
  - If the PlacementRelTo relationship of IfcLocalPlacement is given, it shall point to the local placement of the same IfcSpatialStructureElement, which is used in the ContainedInStructure inverse attribute, or to a spatial structure element at a higher level, referenced by that.

Topology Representation

Instances of IfcStructuralPointReaction may have a topology representation given by a vertex with an optional additional geometric representation by a Cartesian point. It can be provided by either

- IfcVertex
- IfcVertexPoint

which should be the single item of IfcTopologyRepresentation.Items. If no topology representation is given, the location of the placement is taken as the vertex at which the point reaction takes place.

EXPRESS specification:

ENTITY IfcStructuralPointReaction
SUBTYPE OF ( | IfcStructuralReaction);
WHERE
WR61 | : | SIZEOF(['IFCSTRUCTURALLOADRESOURCE.IFCSTRUCTURALLOADSINGLEFORCE', 'IFCSTRUCTURALLOADRESOURCE.IFCSTRUCTURALLOADSINGLEDISPLACEMENT'] * TYPEOF(SELF\IfcStructuralActivity.AppliedLoad)) = 1;
END_ENTITY;

Formal Propositions:

WR61 | : | A structural point reaction should have as a result either a single force, or a single displacement.

Inheritance graph

ENTITY IfcStructuralPointReaction;
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 IfcStructuralActivity;
AppliedLoad | : | IfcStructuralLoad;
GlobalOrLocal | : | IfcGlobalOrLocalEnum;
INVERSE
AssignedToStructuralItem | : | IfcRelConnectsStructuralActivity FOR RelatedStructuralActivity;
ENTITY IfcStructuralReaction;
INVERSE
Causes | : | SET OF IfcStructuralAction FOR CausedBy;
ENTITY IfcStructuralPointReaction;
END_ENTITY;