7.10.3.16 IfcStructuralLoadGroup
7.10.3.16.1 Semantic definition
The entity IfcStructuralLoadGroup is used to structure the physical impacts. By using the grouping features inherited from IfcGroup, instances of IfcStructuralAction (or its subclasses) and of IfcStructuralLoadGroup can be used to define load groups, load cases and load combinations. (See also IfcLoadGroupTypeEnum.)
Informal Propositions:
- Load groups of type LOAD_GROUP shall only contain instances of IfcStructuralAction.
- Load groups of type LOAD_CASE shall always be instantiated from the subtype IfcStructuralLoadCase, not directly from the generic type IfcStructuralLoadGroup itself.
- Instances of IfcStructuralLoadCase shall only contain instances of IfcStructuralAction or/ and instances of IfcStructuralLoadGroup of type LOAD_GROUP.
- Load groups of type LOAD_COMBINATION shall only contain instances of IfcStructuralLoadCase.
7.10.3.16.2 Entity inheritance
7.10.3.16.3 Attributes
| # | Attribute | Type | Description |
|---|---|---|---|
| IfcRoot (4) | |||
| 1 | GlobalId | IfcGloballyUniqueId |
Assignment of a globally unique identifier within the entire software world. |
| 2 | OwnerHistory | 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, |
| 3 | Name | 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. |
| 4 | Description | OPTIONAL IfcText |
Optional description, provided for exchanging informative comments. |
| IfcObjectDefinition (7) | |||
| HasAssignments | SET [0:?] OF IfcRelAssigns FOR RelatedObjects |
Reference to the relationship objects, that assign (by an association relationship) other subtypes of IfcObject to this object instance. Examples are the association to products, processes, controls, resources or groups. |
|
| Nests | SET [0:1] OF IfcRelNests FOR RelatedObjects |
References to the decomposition relationship being a nesting. It determines that this object definition is a part within an ordered whole/part decomposition relationship. An object occurrence or type can only be part of a single decomposition (to allow hierarchical strutures only). |
|
| IsNestedBy | SET [0:?] OF IfcRelNests FOR RelatingObject |
References to the decomposition relationship being a nesting. It determines that this object definition is the whole within an ordered whole/part decomposition relationship. An object or object type can be nested by several other objects (occurrences or types). |
|
| HasContext | SET [0:1] OF IfcRelDeclares FOR RelatedDefinitions |
References to the context providing context information such as project unit or representation context. It should only be asserted for the uppermost non-spatial object. |
|
| IsDecomposedBy | SET [0:?] OF IfcRelAggregates FOR RelatingObject |
References to the decomposition relationship being an aggregation. It determines that this object definition is whole within an unordered whole/part decomposition relationship. An object definitions can be aggregated by several other objects (occurrences or parts). |
|
| Decomposes | SET [0:1] OF IfcRelAggregates FOR RelatedObjects |
References to the decomposition relationship being an aggregation. It determines that this object definition is a part within an unordered whole/part decomposition relationship. An object definitions can only be part of a single decomposition (to allow hierarchical strutures only). |
|
| HasAssociations | SET [0:?] OF IfcRelAssociates FOR RelatedObjects |
Reference to the relationship objects, that associates external references or other resource definitions to the object.. Examples are the association to library, documentation or classification. |
|
| IfcObject (5) | |||
| 5 | ObjectType | OPTIONAL IfcLabel |
The type denotes a particular type that indicates the object further. The use has to be established at the level of instantiable subtypes. In particular it holds the user defined type, if the enumeration of the attribute PredefinedType is set to USERDEFINED. |
| IsDeclaredBy | SET [0:1] OF IfcRelDefinesByObject FOR RelatedObjects |
Link to the relationship object pointing to the declaring object that provides the object definitions for this object occurrence. The declaring object has to be part of an object type decomposition. The associated IfcObject, or its subtypes, contains the specific information (as part of a type, or style, definition), that is common to all reflected instances of the declaring IfcObject, or its subtypes. |
|
| Declares | SET [0:?] OF IfcRelDefinesByObject FOR RelatingObject |
Link to the relationship object pointing to the reflected object(s) that receives the object definitions. The reflected object has to be part of an object occurrence decomposition. The associated IfcObject, or its subtypes, provides the specific information (as part of a type, or style, definition), that is common to all reflected instances of the declaring IfcObject, or its subtypes. |
|
| IsTypedBy | SET [0:1] OF IfcRelDefinesByType FOR RelatedObjects |
Set of relationships to the object type that provides the type definitions for this object occurrence. The then associated IfcTypeObject, or its subtypes, contains the specific information (or type, or style), that is common to all instances of IfcObject, or its subtypes, referring to the same type. |
|
| IsDefinedBy | SET [0:?] OF IfcRelDefinesByProperties FOR RelatedObjects |
Set of relationships to property set definitions attached to this object. Those statically or dynamically defined properties contain alphanumeric information content that further defines the object. |
|
| IfcGroup (2) | |||
| IsGroupedBy | SET [0:?] OF IfcRelAssignsToGroup FOR RelatingGroup |
Reference to the relationship IfcRelAssignsToGroup that assigns the one to many group members to the IfcGroup object. |
|
| ReferencedInStructures | SET [0:?] OF IfcRelReferencedInSpatialStructure FOR RelatedElements |
No description available. |
|
| Click to show 18 hidden inherited attributes Click to hide 18 inherited attributes | |||
| IfcStructuralLoadGroup (7) | |||
| 6 | PredefinedType | IfcLoadGroupTypeEnum |
Selects a predefined type for the load group. It can be differentiated between load groups, load cases, load combinations, or userdefined grouping levels. |
| 7 | ActionType | IfcActionTypeEnum |
Type of actions in the group. Normally needed if 'PredefinedType' specifies a LOAD_CASE. |
| 8 | ActionSource | IfcActionSourceTypeEnum |
Source of actions in the group. Normally needed if 'PredefinedType' specifies a LOAD_CASE. |
| 9 | Coefficient | OPTIONAL IfcRatioMeasure |
Load factor. If omitted, a factor is not yet known or not specified. A load factor of 1.0 shall be explicitly exported as Coefficient = 1.0. |
| 10 | Purpose | OPTIONAL IfcLabel |
Description of the purpose of this instance. Among else, possible values of the Purpose of load combinations are 'SLS', 'ULS', 'ALS' to indicate serviceability, ultimate, or accidental limit state. |
| SourceOfResultGroup | SET [0:1] OF IfcStructuralResultGroup FOR ResultForLoadGroup |
Results which were computed using this load group. |
|
| LoadGroupFor | SET [0:?] OF IfcStructuralAnalysisModel FOR LoadedBy |
Analysis models in which this load group is used. |
|
7.10.3.16.4 Formal propositions
| Name | Description |
|---|---|
| HasObjectType |
The attribute ObjectType shall be given if the predefined type, action type, or action source is set to USERDEFINED. |
|
|
7.10.3.16.5 Property sets
-
Pset_Risk
- RiskName
- RiskType
- NatureOfRisk
- RiskAssessmentMethodology
- UnmitigatedRiskLikelihood
- UnmitigatedRiskConsequence
- UnmitigatedRiskSignificance
- MitigationPlanned
- MitigatedRiskLikelihood
- MitigatedRiskConsequence
- MitigatedRiskSignificance
- MitigationProposed
- AssociatedProduct
- AssociatedActivity
- AssociatedLocation
7.10.3.16.6 Concept usage
| Concept | Usage | Description | |
|---|---|---|---|
| IfcRoot (2) | |||
| Revision Control | General |
Ownership, history, and merge state is captured using IfcOwnerHistory. |
|
| Software Identity | General |
IfcRoot assigns the globally unique ID. In addition it may provide for a name and a description about the concept. |
|
| IfcObjectDefinition (9) | |||
| Aggregation | General |
No description available. |
|
| Approval Association | General |
No description available. |
|
| Classification Association | General |
Any object occurrence or object type can have a reference to a specific classification reference, i.e. to a particular facet within a classification system. |
|
| Constraint Association | General |
No description available. |
|
| Document Association | General |
No description available. |
|
| Library Association | General |
No description available. |
|
| Material Association | General |
No description available. |
|
| Material Single | General |
No description available. |
|
| Nesting | General |
No description available. |
|
| IfcObject (5) | |||
| Assignment to Group | General |
No description available. |
|
| Object Predefined Type | General |
No description available. |
|
| Object Typing | General |
Any object occurrence can be typed by being assigned to a common object type utilizing this concept. A particular rule, restricting the applicable subtypes of IfcTypeObject that can be assigned, is introduced by overriding this concept at the level of subtypes of IfcObject. This concept can be applied to the following resources: |
|
| Object User Identity | General |
An attribute Name and optionally Description can be used for all subypes of IfcObject. For those subtypes, that have an object type definition, such as ifcBeam - IfcBeamType, the common Name and optionally Description is associated with the object type. |
|
| Property Sets with Override | General |
Any object occurrence can hold property sets, either directly at the object occurrence as element specific property sets, or at the object type, as type property sets. In this case, the properties that are provided to the object occurrence are the combinations of element specific and type properties. In case, that the same property (within the same property set, is defined both, in occurrence and type properties, the property value of the occurrence property overrides the property value of the type property. |
|
| IfcGroup (2) | |||
| Group Assignment | General |
The IfcGroup establishes an arbitrary collection of objects through utilizing this concept. |
|
| Property Sets for Objects | General |
This concept can be applied to the following resources: |
|
| Click to show 18 hidden inherited concepts Click to hide 18 inherited concepts | |||
7.10.3.16.7 Formal representation
ENTITY IfcStructuralLoadGroup
SUPERTYPE OF (ONEOF
(IfcStructuralLoadCase))
SUBTYPE OF (IfcGroup);
PredefinedType : IfcLoadGroupTypeEnum;
ActionType : IfcActionTypeEnum;
ActionSource : IfcActionSourceTypeEnum;
Coefficient : OPTIONAL IfcRatioMeasure;
Purpose : OPTIONAL IfcLabel;
INVERSE
SourceOfResultGroup : SET [0:1] OF IfcStructuralResultGroup FOR ResultForLoadGroup;
LoadGroupFor : SET [0:?] OF IfcStructuralAnalysisModel FOR LoadedBy;
WHERE
HasObjectType : (
(PredefinedType <> IfcLoadGroupTypeEnum.USERDEFINED) AND
(ActionType <> IfcActionTypeEnum.USERDEFINED) AND
(ActionSource <> IfcActionSourceTypeEnum.USERDEFINED)
) OR EXISTS(SELF\IfcObject.ObjectType);
END_ENTITY;