IfcIShapeProfileDef

BACnet MVD

#### IfcIShapeProfileDef

Natural language names

| I-Profil - parametrische Definition
| IShape Profile Def
| Définition de section d'un profil en I

Change log

Item | SPF | XML | Change | Description
--- | --- | --- | --- | ---
IFC2x3 to IFC4
IfcIShapeProfileDef |  |  |  |
Position |  |  | MODIFIED | Instantiation changed to OPTIONAL.
FilletRadius |  |  | MODIFIED | Type changed from IfcPositiveLengthMeasure to IfcNonNegativeLengthMeasure.
FlangeEdgeRadius |  |  | ADDED |
FlangeSlope |  |  | ADDED |

##### Semantic definitions at the entity

Entity definition

IfcIShapeProfileDef defines a section profile that provides the defining parameters of an 'I' or 'H' section. The I-shape profile has values for its overall depth, width and its web and flange thicknesses. Additionally a fillet radius, flange edge radius, and flange slope may be given. This profile definition represents an I-section which is symmetrical about its major and minor axes; top and bottom flanges are equal and centred on the web.

> HISTORY New entity in IFC2x.

> IFC4 CHANGE Type of FilletRadius relaxed to allow for zero radius. Attributes FlangeEdgeRadius and FlangeSlope added.

Figure 365 illustrates parameters of the I-shape profile definition.

Position
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. Explicit coordinate offsets are used to define cardinal points (e.g. upper-left bound).

Parameter
The parameterized profile is defined by a set of parameter attributes, see attribute definition below.

Note: The black coordinate axes show the underlying coordinate system of the swept surface or swept area solid

Position
The profile is inserted into the underlying coordinate system of the swept area solid by using the Position attribute. In this example (cardinal point of lower left corner) the attribute values of IfcAxis2Placement2D are:

> `Location = IfcCartesianPoint(<1/2 OverallWidth>,<1/2 OverallDepth>)
> RefDirection = NIL (defaults to 1.,0.)`

Parameter
If the FilletRadius is given, it is equally applied to all four corners created by the web and flanges.

Figure 365 — I-shape profile

Attribute definitions

# | Attribute | Type | Cardinality | Description | B
--- | --- | --- | --- | --- | ---
4 | OverallWidth | IfcPositiveLengthMeasure |  | Total extent of the width, defined parallel to the x axis of the position coordinate system. | X | X
5 | OverallDepth | IfcPositiveLengthMeasure |  | Total extent of the depth, defined parallel to the y axis of the position coordinate system. | X | X
6 | WebThickness | IfcPositiveLengthMeasure |  | Thickness of the web of the I-shape. The web is centred on the x-axis and the y-axis of the position coordinate system. | X | X
7 | FlangeThickness | IfcPositiveLengthMeasure |  | Flange thickness of the I-shape. Both, the upper and the lower flanges have the same thickness and they are centred on the y-axis of the position coordinate system. | X | X
8 | FilletRadius | IfcNonNegativeLengthMeasure | ? | The fillet between the web and the flange. 0 if sharp-edged, omitted if unknown. | X | X
9 | FlangeEdgeRadius | IfcNonNegativeLengthMeasure | ? | Radius of the lower edges of the top flange and the upper edges of the bottom flange. 0 if sharp-edged, omitted if unknown. | X | X
10 | FlangeSlope | IfcPlaneAngleMeasure | ? | Slope of the lower faces of the top flange and of the upper faces of the bottom flange. Non-zero in case of tapered flanges, 0 in case of parallel flanges, omitted if unknown. | X | X

Formal Propositions

Rule | Description
--- | ---
ValidFlangeThickness | The sum of flange thicknesses shall be less than the overall depth.
ValidWebThickness | The web thickness shall be less then the flange width.
ValidFilletRadius | The FilletRadius, if given, shall be within the range of allowed values.

##### 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
IfcIShapeProfileDef
4 | OverallWidth | IfcPositiveLengthMeasure |  | Total extent of the width, defined parallel to the x axis of the position coordinate system. | X | X
5 | OverallDepth | IfcPositiveLengthMeasure |  | Total extent of the depth, defined parallel to the y axis of the position coordinate system. | X | X
6 | WebThickness | IfcPositiveLengthMeasure |  | Thickness of the web of the I-shape. The web is centred on the x-axis and the y-axis of the position coordinate system. | X | X
7 | FlangeThickness | IfcPositiveLengthMeasure |  | Flange thickness of the I-shape. Both, the upper and the lower flanges have the same thickness and they are centred on the y-axis of the position coordinate system. | X | X
8 | FilletRadius | IfcNonNegativeLengthMeasure | ? | The fillet between the web and the flange. 0 if sharp-edged, omitted if unknown. | X | X
9 | FlangeEdgeRadius | IfcNonNegativeLengthMeasure | ? | Radius of the lower edges of the top flange and the upper edges of the bottom flange. 0 if sharp-edged, omitted if unknown. | X | X
10 | FlangeSlope | IfcPlaneAngleMeasure | ? | Slope of the lower faces of the top flange and of the upper faces of the bottom flange. Non-zero in case of tapered flanges, 0 in case of parallel flanges, omitted if unknown. | X | X

##### Examples

- Beam standard case
- Beam extruded solid
- Beam revolved solid
- Column extruded solid
- Beam varying profiles

##### Formal representations

XML Specification
`<xs:element name="IfcIShapeProfileDef" type="ifc:IfcIShapeProfileDef" substitutionGroup="ifc:IfcParameterizedProfileDef" nillable="true"/>
<xs:complexType name="IfcIShapeProfileDef">
<xs:complexContent>
<xs:extension base="ifc:IfcParameterizedProfileDef">
<xs:attribute name="OverallWidth" type="ifc:IfcPositiveLengthMeasure" use="optional"/>
<xs:attribute name="OverallDepth" type="ifc:IfcPositiveLengthMeasure" use="optional"/>
<xs:attribute name="WebThickness" type="ifc:IfcPositiveLengthMeasure" use="optional"/>
<xs:attribute name="FlangeThickness" type="ifc:IfcPositiveLengthMeasure" use="optional"/>
<xs:attribute name="FilletRadius" type="ifc:IfcNonNegativeLengthMeasure" use="optional"/>
<xs:attribute name="FlangeEdgeRadius" type="ifc:IfcNonNegativeLengthMeasure" use="optional"/>
<xs:attribute name="FlangeSlope" type="ifc:IfcPlaneAngleMeasure" use="optional"/>
</xs:extension>
</xs:complexContent>
</xs:complexType>
`
EXPRESS Specification
`ENTITY IfcIShapeProfileDef
SUBTYPE OF (IfcParameterizedProfileDef);
OverallWidth : IfcPositiveLengthMeasure;
OverallDepth : IfcPositiveLengthMeasure;
WebThickness : IfcPositiveLengthMeasure;
FlangeThickness : IfcPositiveLengthMeasure;
FilletRadius : OPTIONAL IfcNonNegativeLengthMeasure;
FlangeEdgeRadius : OPTIONAL IfcNonNegativeLengthMeasure;
FlangeSlope : OPTIONAL IfcPlaneAngleMeasure;
WHERE
ValidFlangeThickness : (2. * FlangeThickness) < OverallDepth;
ValidWebThickness : WebThickness < OverallWidth;
ValidFilletRadius : NOT(EXISTS(FilletRadius)) OR
((FilletRadius <= (OverallWidth - WebThickness)/2.) AND
(FilletRadius <= (OverallDepth - (2. * FlangeThickness))/2.));
END_ENTITY;

EXPRESS-G diagram

`

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