IfcCenterLineProfileDef

BACnet MVD

#### IfcCenterLineProfileDef

Natural language names

| Profildefinition mit Hilfe Mittellinie
| Center Line Profile Def

##### Semantic definitions at the entity

Entity definition

The profile IfcCenterLineProfileDef defines an arbitrary two-dimensional open, not self intersecting profile for the use within the swept solid geometry. It is given by an area defined by applying a constant thickness to a centerline, generating an area from which the solid can be constructed.

Among else, IfcCenterLineProfileDef is used to model cold-formed steel or aluminium sections (Sigma, Zeta, Omega, and similar sections which are not covered by subtypes of IfcParameterizedProfileDef). However, since IfcCenterLineProfileDef does not provide shape parameters except for the thickness, there is generally a need to further specify the profile definition by means of

- the name,
- external reference to a document or library,
- profile properties,

or a combination of them. See IfcProfileDef for guidance on external references for profiles.

> HISTORY New entity in IFC2x3.

Informal Propositions:

1. The Curve has to be an open curve.
2. The Curve has to be a non-intersecting curve.

Figure 359 illustrates the center line profile definition. The Curve is defined in the underlying coordinate system. The underlying coordinate system is defined by the swept surface that uses the profile definition. It is the xy plane of:

- IfcSweptSurface.Position

The Curve attribute defines a two dimensional open bounded curve. The Thickness attribute defines a constant thickness along the curve.

Figure 359 — Centerline profile

Attribute definitions

# | Attribute | Type | Cardinality | Description | B
--- | --- | --- | --- | --- | ---
4 | Thickness | IfcPositiveLengthMeasure |  | Constant thickness applied along the center line. |  | X

##### 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

IfcArbitraryOpenProfileDef
3 | Curve | IfcBoundedCurve |  | Open bounded curve defining the profile. |  | X
IfcCenterLineProfileDef
4 | Thickness | IfcPositiveLengthMeasure |  | Constant thickness applied along the center line. |  | X

##### Formal representations

XML Specification
`<xs:element name="IfcCenterLineProfileDef" type="ifc:IfcCenterLineProfileDef" substitutionGroup="ifc:IfcArbitraryOpenProfileDef" nillable="true"/>
<xs:complexType name="IfcCenterLineProfileDef">
<xs:complexContent>
<xs:extension base="ifc:IfcArbitraryOpenProfileDef">
<xs:attribute name="Thickness" type="ifc:IfcPositiveLengthMeasure" use="optional"/>
</xs:extension>
</xs:complexContent>
</xs:complexType>
`
EXPRESS Specification
`ENTITY IfcCenterLineProfileDef
SUBTYPE OF (IfcArbitraryOpenProfileDef);
Thickness : IfcPositiveLengthMeasure;
END_ENTITY;

EXPRESS-G diagram

`

Link to this page