IfcCShapeProfileDef

Natural language names
C-Profil - parametrische Definition
CShape Profile Def
Définition de section d'un profil en C
Change log
ItemSPFXMLChangeDescription
IFC2x3 to IFC4
    IfcCShapeProfileDef
      PositionMODIFIEDInstantiation changed to OPTIONAL.
      InternalFilletRadiusMODIFIEDType changed from IfcPositiveLengthMeasure to IfcNonNegativeLengthMeasure.
      CentreOfGravityInXXDELETED
Semantic definitions at the entity
Entity definition

IfcCShapeProfileDef defines a section profile that provides the defining parameters of a C-shaped section to be used by the swept area solid. This section is typically produced by cold forming steel. Its parameters and orientation relative to the position coordinate system are according to the following illustration. The centre of the position coordinate system is in the profile's centre of the bounding box.

HISTORY  New entity in IFC2x2.
IFC2x3 CHANGE  All profile origins are now in the center of the bounding box.
IFC4 CHANGE  Type of InternalFilletRadius relaxed to allow for zero radius. Trailing attribute CentreOfGravityInX deleted, use respective property in IfcExtendedProfileProperties instead.

Figure 419 illustrates parameters of the C-shape profile definition. The parameterized profile defines its own position coordinate system. The underlying coordinate system is defined by the swept area solid that uses the profile definition. It is the xy plane of:

By using offsets of the position location, the parameterized profile can be positioned centric (using x,y offsets = 0.), or at any position relative to the profile. The parameterized profile is defined by a set of parameter attributes. In the illustrated example, the 'CentreOfGravityInX' property in IfcExtendedProfileProperties, if provided, is negative.

C-shape profile

Figure 419 — C-shape profile

Attribute definitions
#AttributeTypeCardinalityDescription G
4DepthIfcPositiveLengthMeasure Profile depth, see illustration above (= h). X
5WidthIfcPositiveLengthMeasure Profile width, see illustration above (= b).X
6WallThicknessIfcPositiveLengthMeasure Constant wall thickness of profile (= ts).X
7GirthIfcPositiveLengthMeasure Lengths of girth, see illustration above (= c). X
8InternalFilletRadiusIfcNonNegativeLengthMeasure? Internal fillet radius according the above illustration (= r1).X
Formal Propositions
RuleDescription
ValidGirthThe girth shall be smaller than half of the depth.
ValidInternalFilletRadiusIf the value for InternalFilletRadius is given, it shall be small enough to fit into the inner space.
ValidWallThicknessThe WallThickness shall be smaller than half of the Width and half of the Depth.
Inherited definitions from supertypes
Entity inheritance IfcParameterizedProfileDef IfcProfileDef
Attribute inheritance
#AttributeTypeCardinalityDescriptionG
IfcProfileDef
1ProfileTypeIfcProfileTypeEnum Defines the type of geometry into which this profile definition shall be resolved, either a curve or a surface area. In case of curve the profile should be referenced by a swept surface, in case of area the profile should be referenced by a swept area solid.X
2ProfileNameIfcLabel? Human-readable name of the profile, for example according to a standard profile table. As noted above, machine-readable standardized profile designations should be provided in IfcExternalReference.ItemReference. X
HasExternalReferenceIfcExternalReferenceRelationship
@RelatedResourceObjects
S[0:?]Reference to external information, e.g. library, classification, or document information, which is associated with the profile.
IFC4 CHANGE New inverse attribute
X
HasPropertiesIfcProfileProperties
@ProfileDefinition
S[0:?]Additional properties of the profile, for example mechanical properties.
IFC4 CHANGE New inverse attribute
X
IfcParameterizedProfileDef
3PositionIfcAxis2Placement2D? Position coordinate system of the parameterized profile definition. If unspecified, no translation and no rotation is applied. X
IfcCShapeProfileDef
4DepthIfcPositiveLengthMeasure Profile depth, see illustration above (= h). X
5WidthIfcPositiveLengthMeasure Profile width, see illustration above (= b).X
6WallThicknessIfcPositiveLengthMeasure Constant wall thickness of profile (= ts).X
7GirthIfcPositiveLengthMeasure Lengths of girth, see illustration above (= c). X
8InternalFilletRadiusIfcNonNegativeLengthMeasure? Internal fillet radius according the above illustration (= r1).X
Definitions applying to General Usage

Concept inheritance

#ConceptTemplateModel View
IfcProfileDef
Property Sets for ObjectsProperty Sets for ObjectsGeneral Usage
Formal representations
XML Specification
 <xs:element name="IfcCShapeProfileDef" type="ifc:IfcCShapeProfileDef" substitutionGroup="ifc:IfcParameterizedProfileDef" nillable="true"/>
 <xs:complexType name="IfcCShapeProfileDef">
  <xs:complexContent>
   <xs:extension base="ifc:IfcParameterizedProfileDef">
    <xs:attribute name="Depth" type="ifc:IfcPositiveLengthMeasure" use="optional"/>
    <xs:attribute name="Width" type="ifc:IfcPositiveLengthMeasure" use="optional"/>
    <xs:attribute name="WallThickness" type="ifc:IfcPositiveLengthMeasure" use="optional"/>
    <xs:attribute name="Girth" type="ifc:IfcPositiveLengthMeasure" use="optional"/>
    <xs:attribute name="InternalFilletRadius" type="ifc:IfcNonNegativeLengthMeasure" use="optional"/>
   </xs:extension>
  </xs:complexContent>
 </xs:complexType>
EXPRESS Specification
ENTITY IfcCShapeProfileDef
 SUBTYPE OF (IfcParameterizedProfileDef);
  Depth : IfcPositiveLengthMeasure;
  Width : IfcPositiveLengthMeasure;
  WallThickness : IfcPositiveLengthMeasure;
  Girth : IfcPositiveLengthMeasure;
  InternalFilletRadius : OPTIONAL IfcNonNegativeLengthMeasure;
 WHERE
  ValidGirth : Girth < (Depth / 2.);
  ValidInternalFilletRadius : NOT(EXISTS(InternalFilletRadius)) OR
((InternalFilletRadius <= Width/2. - WallThickness) AND (InternalFilletRadius <= Depth/2. - WallThickness));
  ValidWallThickness : (WallThickness < Width/2.) AND (WallThickness < Depth/2.);
END_ENTITY;

Link to EXPRESS-G diagram EXPRESS-G diagram

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