 | Platte / Scheibe |
 | Structural Surface Member |
| Item | SPF | XML | Change | Description | IFC2x3 to IFC4 |
|---|---|---|---|---|
| IfcStructuralSurfaceMember | ||||
| OwnerHistory | MODIFIED | Instantiation changed to OPTIONAL. | ||
| PredefinedType | MODIFIED | Type changed from IfcStructuralSurfaceTypeEnum to IfcStructuralSurfaceMemberTypeEnum. |
Instances of IfcStructuralSurfaceMember describe face members, that is, structural analysis idealizations of slabs, walls, and shells. Surface members may be planar or curved.
HISTORY New entity in IFC2x2.
IFC4 CHANGE Use definitions changed, WHERE rule added.
Coordinate Systems:
See definitions at IfcStructuralItem. The local coordinate system is established by the reference surface given by topology representation.
Material Use Definition
The material of direct instances IfcStructuralSurfaceMember (in contrast to instances of the subtype IfcStructuralSurfaceMemberVarying) is defined by IfcMaterial and attached by the IfcRelAssociatesMaterial.RelatingMaterial. It is accessible by the inverse HasAssociations relationship.
The material is specified minimally by a name which corresponds with an agreed upon standardized structural material designation. An external reference to the source which specifies the material designation should be provided. Alternatively, structural material properties may be provided by means of IfcMechanicalMaterialProperties and IfcExtendedMaterialProperties.
Direct instances of IfcStructuralSurfaceMember are assumed to be located centrically relative to their reference surface. Their depth is provided in the attribute Thickness.
| # | Attribute | Type | Cardinality | Description | G |
|---|---|---|---|---|---|
| 8 | PredefinedType | IfcStructuralSurfaceMemberTypeEnum | Type of member with respect to its load carrying behavior in this analysis idealization. | X | |
| 9 | Thickness | IfcPositiveLengthMeasure | ? | Defines the typically understood thickness of the structural surface member, measured normal to its reference surface. | X |
| Rule | Description |
|---|---|
| HasObjectType | The attribute ObjectType shall be given if the predefined type is set to USERDEFINED. |
| # | Attribute | Type | Cardinality | Description | G |
|---|---|---|---|---|---|
| IfcRoot | |||||
| 1 | GlobalId | IfcGloballyUniqueId | Assignment of a globally unique identifier within the entire software world. | X | |
| 2 | OwnerHistory | 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. | X |
| 3 | Name | 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. | X |
| 4 | Description | IfcText | ? | Optional description, provided for exchanging informative comments. | X |
| IfcObjectDefinition | |||||
| HasAssignments | IfcRelAssigns @RelatedObjects | S[0:?] | 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. | X | |
| Nests | IfcRelNests @RelatedObjects | S[0:1] | 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).
IFC4 CHANGE The inverse attribute datatype has been added and separated from Decomposes defined at IfcObjectDefinition. | X | |
| IsNestedBy | IfcRelNests @RelatingObject | S[0:?] | 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).
IFC4 CHANGE The inverse attribute datatype has been added and separated from IsDecomposedBy defined at IfcObjectDefinition. | X | |
| HasContext | IfcRelDeclares @RelatedDefinitions | S[0:1] | 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.
IFC4 CHANGE The inverse attribute datatype has been added. | X | |
| IsDecomposedBy | IfcRelAggregates @RelatingObject | S[0:?] | 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).
IFC4 CHANGE The inverse attribute datatype has been changed from the supertype IfcRelDecomposes to subtype IfcRelAggregates. | X | |
| Decomposes | IfcRelAggregates @RelatedObjects | S[0:1] | 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).
IFC4 CHANGE The inverse attribute datatype has been changed from the supertype IfcRelDecomposes to subtype IfcRelAggregates. | X | |
| HasAssociations | IfcRelAssociates @RelatedObjects | S[0:?] | 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. | X | |
| IfcObject | |||||
| 5 | ObjectType | 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.
| X |
| IsDeclaredBy | IfcRelDefinesByObject @RelatedObjects | S[0:1] | 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.
IFC4 CHANGE New inverse relationship, change made with upward compatibility for file based exchange. | X | |
| Declares | IfcRelDefinesByObject @RelatingObject | S[0:?] | 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.
IFC4 CHANGE New inverse relationship, change made with upward compatibility for file based exchange. | X | |
| IsTypedBy | IfcRelDefinesByType @RelatedObjects | S[0:1] | 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.
IFC4 CHANGE New inverse relationship, the link to IfcRelDefinesByType had previously be included in the inverse relationship IfcRelDefines. Change made with upward compatibility for file based exchange. | X | |
| IsDefinedBy | IfcRelDefinesByProperties @RelatedObjects | S[0:?] | 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.
IFC4 CHANGE The data type has been changed from IfcRelDefines to IfcRelDefinesByProperties with upward compatibility for file based exchange. | X | |
| IfcProduct | |||||
| 6 | ObjectPlacement | IfcObjectPlacement | ? | Placement of the product in space, the placement can either be absolute (relative to the world coordinate system), relative (relative to the object placement of another product), or constraint (e.g. relative to grid axes). It is determined by the various subtypes of IfcObjectPlacement, which includes the axis placement information to determine the transformation for the object coordinate system. | X |
| 7 | Representation | IfcProductRepresentation | ? | Reference to the representations of the product, being either a representation (IfcProductRepresentation) or as a special case a shape representations (IfcProductDefinitionShape). The product definition shape provides for multiple geometric representations of the shape property of the object within the same object coordinate system, defined by the object placement. | X |
| ReferencedBy | IfcRelAssignsToProduct @RelatingProduct | S[0:?] | Reference to the IfcRelAssignsToProduct relationship, by which other products, processes, controls, resources or actors (as subtypes of IfcObjectDefinition) can be related to this product. | X | |
| IfcStructuralItem | |||||
| AssignedStructuralActivity | IfcRelConnectsStructuralActivity @RelatingElement | S[0:?] | Inverse relationship to all structural activities (i.e. to actions or reactions) which are assigned to this structural member. | X | |
| IfcStructuralMember | |||||
| ConnectedBy | IfcRelConnectsStructuralMember @RelatingStructuralMember | S[0:?] | Inverse relationship to all structural connections (i.e. to supports or connecting elements) which are defined for this structural member. | X | |
| IfcStructuralSurfaceMember | |||||
| 8 | PredefinedType | IfcStructuralSurfaceMemberTypeEnum | Type of member with respect to its load carrying behavior in this analysis idealization. | X | |
| 9 | Thickness | IfcPositiveLengthMeasure | ? | Defines the typically understood thickness of the structural surface member, measured normal to its reference surface. | X |
Material Layer Set Usage
The Material Layer Set Usage concept applies to this entity.
The material of direct instances IfcStructuralSurfaceMember (in contrast to instances of the subtype IfcStructuralSurfaceMemberVarying) is defined by IfcMaterialLayerSetUsage and attached by the IfcRelAssociatesMaterial.RelatingMaterial. It is accessible by the inverse HasAssociations relationship.
The material is specified minimally by a name which corresponds with an agreed upon standardized structural material designation. An external reference to the source which specifies the material designation should be provided. Alternatively, structural material properties may be provided by means of IfcMaterialProperties.
In the absense of material layer set usage, direct instances of IfcStructuralSurfaceMember are assumed to be located centrically relative to their reference surface. Their depth is provided in the attribute Thickness.
Reference Topology
The Reference Topology concept template applies to this entity as shown in Table 636.
| ||
Table 636 — IfcStructuralSurfaceMember Reference Topology |
Direct instances of IfcStructuralSurfaceMember shall have a topology representation which consists of one IfcFaceSurface, representing the reference surface of the surface member. See definitions at IfcStructuralItem for further specifications.
The local coordinate system is established by the reference surface given by topology representation.
Structural Connectivity
The Structural Connectivity concept template applies to this entity as shown in Table 637.
| ||||||
Table 637 — IfcStructuralSurfaceMember Structural Connectivity |
Instance diagram
<?xml version="1.0"?>
<ConceptRoot xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" uuid="b5b74da7-fec9-4ef9-b5e1-73b7ff050e91" name="IfcStructuralSurfaceMember" status="sample" applicableRootEntity="IfcStructuralSurfaceMember">
<Applicability uuid="00000000-0000-0000-0000-000000000000" status="sample">
<Template ref="95ecd465-4b42-4a00-929a-7c80856ea08b" />
<TemplateRules operator="and" />
</Applicability>
<Concepts>
<Concept uuid="464831c6-2e7f-4a28-a579-f594b7df06a7" name="Material Layer Set Usage" status="sample" override="false">
<Template ref="6d5fb86f-3f2d-49fb-9528-077855ddcc47" />
</Concept>
<Concept uuid="3c54c12b-cd40-4f98-a65f-124b53a0a4f1" name="Reference Topology" status="sample" override="false">
<Template ref="79dd6317-2390-44ca-88c2-70d46cd5b969" />
<TemplateRules operator="and">
<TemplateRule Parameters="Topology[Type]='IfcFaceSurface'" />
</TemplateRules>
</Concept>
<Concept uuid="91437328-4773-43fb-a284-ccf703da116b" name="Structural Connectivity" status="sample" override="false">
<Template ref="f4f75d4f-6d38-4cbe-9efb-dfb58440dfcb" />
<TemplateRules operator="and">
<TemplateRule Description="Connections to curve members along edge(s) of surface." Parameters="StructuralConnection[Type]='IfcStructuralCurveConnection'" />
<TemplateRule Description="Connections to surface members within face(s) of surface." Parameters="StructuralConnection[Type]='IfcStructuralSurfaceConnection'" />
</TemplateRules>
</Concept>
</Concepts>
</ConceptRoot>
| # | Concept | Template | Model View |
|---|---|---|---|
| IfcRoot | |||
| Identity | Software Identity | General Usage | |
| Revision Control | Revision Control | General Usage | |
| IfcObjectDefinition | |||
| Classification Association | Classification Association | General Usage | |
| IfcObject | |||
| Object User Identity | Object User Identity | General Usage | |
| Object Predefined Type | Object Predefined Type | General Usage | |
| Object Typing | Object Typing | General Usage | |
| Property Sets for Objects | Property Sets for Objects | General Usage | |
| Property Sets with Override | Property Sets with Override | General Usage | |
| IfcProduct | |||
| Product Placement | Product Placement | General Usage | |
| Product Geometric Representation | Product Geometric Representation | General Usage | |
| IfcStructuralSurfaceMember | |||
| Material Layer Set Usage | Material Layer Set Usage | General Usage | |
| Reference Topology | Reference Topology | General Usage | |
| Structural Connectivity | Structural Connectivity | General Usage | |
<xs:element name="IfcStructuralSurfaceMember" type="ifc:IfcStructuralSurfaceMember" substitutionGroup="ifc:IfcStructuralMember" nillable="true"/>
<xs:complexType name="IfcStructuralSurfaceMember">
<xs:complexContent>
<xs:extension base="ifc:IfcStructuralMember">
<xs:attribute name="PredefinedType" type="ifc:IfcStructuralSurfaceMemberTypeEnum" use="optional"/>
<xs:attribute name="Thickness" type="ifc:IfcPositiveLengthMeasure" use="optional"/>
</xs:extension>
</xs:complexContent>
</xs:complexType>
ENTITY IfcStructuralSurfaceMember
SUPERTYPE OF(IfcStructuralSurfaceMemberVarying)
SUBTYPE OF (IfcStructuralMember);
PredefinedType : IfcStructuralSurfaceMemberTypeEnum;
Thickness : OPTIONAL IfcPositiveLengthMeasure;
WHERE
HasObjectType : (PredefinedType <> IfcStructuralSurfaceMemberTypeEnum.USERDEFINED) OR EXISTS(SELF\IfcObject.ObjectType);
END_ENTITY;
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