IfcCShapeProfileDef

BACnet MVD

#### IfcCShapeProfileDef

Natural language names

| C-Profil - parametrische Definition
| CShape Profile Def
| Définition de section d'un profil en C

Change log

Item | SPF | XML | Change | Description
--- | --- | --- | --- | ---
IFC2x3 to IFC4
IfcCShapeProfileDef |  |  |  |
Position |  |  | MODIFIED | Instantiation changed to OPTIONAL.
InternalFilletRadius |  |  | MODIFIED | Type changed from IfcPositiveLengthMeasure to IfcNonNegativeLengthMeasure.
CentreOfGravityInX | X |  | DELETED |

##### 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 362 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:

- IfcSweptAreaSolid.Position

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.

Figure 362 — C-shape profile

Attribute definitions

# | Attribute | Type | Cardinality | Description | B
--- | --- | --- | --- | --- | ---
4 | Depth | IfcPositiveLengthMeasure |  | Profile depth, see illustration above (= h). | X | X
5 | Width | IfcPositiveLengthMeasure |  | Profile width, see illustration above (= b). | X | X
6 | WallThickness | IfcPositiveLengthMeasure |  | Constant wall thickness of profile (= ts). | X | X
7 | Girth | IfcPositiveLengthMeasure |  | Lengths of girth, see illustration above (= c). | X | X
8 | InternalFilletRadius | IfcNonNegativeLengthMeasure | ? | Internal fillet radius according the above illustration (= r1). | X | X

Formal Propositions

Rule | Description
--- | ---
ValidGirth | The girth shall be smaller than half of the depth.
ValidInternalFilletRadius | If the value for InternalFilletRadius is given, it shall be small enough to fit into the inner space.
ValidWallThickness | The WallThickness shall be smaller than half of the Width and half of the Depth.

##### Inherited definitions from supertypes

Entity inheritance
Attribute inheritance

# | Attribute | Type | Cardinality | Description | B
--- | --- | --- | --- | --- | ---
IfcProfileDef
1 | ProfileType | IfcProfileTypeEnum |  | 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 | X
2 | ProfileName | IfcLabel | ? | 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 | X

HasExternalReference

IfcExternalReferenceRelationship
@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

HasProperties

IfcProfileProperties
@ProfileDefinition

S[0:?]

Additional properties of the profile, for example mechanical properties.

> IFC4 CHANGE New inverse attribute

X

IfcParameterizedProfileDef
3 | Position | IfcAxis2Placement2D | ? | Position coordinate system of the parameterized profile definition. If unspecified, no translation and no rotation is applied. | X | X
IfcCShapeProfileDef
4 | Depth | IfcPositiveLengthMeasure |  | Profile depth, see illustration above (= h). | X | X
5 | Width | IfcPositiveLengthMeasure |  | Profile width, see illustration above (= b). | X | X
6 | WallThickness | IfcPositiveLengthMeasure |  | Constant wall thickness of profile (= ts). | X | X
7 | Girth | IfcPositiveLengthMeasure |  | Lengths of girth, see illustration above (= c). | X | X
8 | InternalFilletRadius | IfcNonNegativeLengthMeasure | ? | Internal fillet radius according the above illustration (= r1). | X | X

##### 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;

EXPRESS-G diagram

`

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