8.15.3.13 IfcLShapeProfileDef

8.15.3.13.1 Semantic definition

IfcLShapeProfileDef defines a section profile that provides the defining parameters of an L-shaped section (equilateral L profiles are also covered by this entity) to be used by the swept area solid. Its parameters and orientation relative to the position coordinate system are according to the following illustration. The shorter leg has the same direction as the positive Position.P[1]-axis, the longer or equal leg the same as the positive Position.P[2]-axis. The centre of the position coordinate system is in the profiles centre of the bounding box.

Figure 8.15.3.13.A and Figure 8.15.3.13.B illustrates parameters of equal-sided and non-equal sided L-shaped section definitions.

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.

In the illustrated example, the 'CentreOfGravityInX' and 'CentreOfGravityInY' properties in IfcProfileProperties, if provided, are both negative.

equal sided L-shape — Figure 8.15.3.13.B — Equal L-shape profile

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 gravity) the attribute values of IfcAxis2Placement2D are:

 Location = IfcCartesianPoint(+|CentreOfGravityInX|, +|CentreOfGravityInY|)
RefDirection = NIL (defaults to 1.,0.)

In the illustrated example, the x and y value of Position.Location, i.e. the measures |CentreOfGravityInX| and |CentreOfGravityInY| are both positive. On the other hand, the properties named 'CentreOfGravityInX' and 'CentreOfGravityInY' in IfcProfileProperties, if provided, must both be set to 0 now because the centre of gravity of the resulting profile definition is located in the coordinate origin.

8.15.3.13.2 Entity inheritance

- IfcProfileDef

8.15.3.13.3 Attributes

#	Attribute	Type	Description
IfcProfileDef (4)
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.
2	ProfileName	OPTIONAL 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.
	HasExternalReference	SET [0:?] OF IfcExternalReferenceRelationship FOR RelatedResourceObjects	Reference to external information, e.g. library, classification, or document information, which is associated with the profile. IFC4-CHANGE New inverse attribute
	HasProperties	SET [0:?] OF IfcProfileProperties FOR ProfileDefinition	Additional properties of the profile, for example mechanical properties. IFC4-CHANGE New inverse attribute
IfcParameterizedProfileDef (1)
3	Position	OPTIONAL IfcAxis2Placement2D	Position coordinate system of the parameterized profile definition. If unspecified, no translation and no rotation is applied.
Click to show 5 hidden inherited attributes
IfcLShapeProfileDef (6)
4	Depth	IfcPositiveLengthMeasure	Leg length, see illustration above (= h). Same as the overall depth.
5	Width	OPTIONAL IfcPositiveLengthMeasure	Leg length, see illustration above (= b). Same as the overall width. This attribute is formally optional for historic reasons only. Whenever the width is known, it shall be provided by value.
6	Thickness	IfcPositiveLengthMeasure	Constant wall thickness of profile, see illustration above (= ts).
7	FilletRadius	OPTIONAL IfcNonNegativeLengthMeasure	Fillet radius according the above illustration (= r1).
8	EdgeRadius	OPTIONAL IfcNonNegativeLengthMeasure	Edge radius according the above illustration (= r2).
9	LegSlope	OPTIONAL IfcPlaneAngleMeasure	Slope of the inner face of each leg of the profile.

Table 8.15.3.13.C

8.15.3.13.4 Formal propositions

Name	Description
ValidThickness	The thickness shall be smaller than the depth and width.
`(Thickness < Depth) AND (NOT(EXISTS(Width)) OR (Thickness < Width))`

Table 8.15.3.13.D

8.15.3.13.5 Property sets

Pset_ProfileMechanical
- MassPerLength
- CrossSectionArea
- Perimeter
- MinimumPlateThickness
- MaximumPlateThickness
- CentreOfGravityInX
- CentreOfGravityInY
- ShearCentreZ
- ShearCentreY
- MomentOfInertiaY
- MomentOfInertiaZ
- MomentOfInertiaYZ
- TorsionalConstantX
- WarpingConstant
- ShearDeformationAreaZ
- ShearDeformationAreaY
- MaximumSectionModulusY
- MinimumSectionModulusY
- MaximumSectionModulusZ
- MinimumSectionModulusZ
- TorsionalSectionModulus
- ShearAreaZ
- ShearAreaY
- PlasticShapeFactorY
- PlasticShapeFactorZ

8.15.3.13.6 Concept usage

Concept	Usage	Description
IfcProfileDef (1)
Property Sets for Profiles	General	This concept can be applied to the following resources: Pset_ProfileMechanical
Click to show 1 hidden inherited concepts

Concept

Usage

Description

IfcProfileDef (1)

Click to show 1 hidden inherited concepts

Table 8.15.3.13.E

8.15.3.13.7 Formal representation

 ENTITY IfcLShapeProfileDef
 SUBTYPE OF (IfcParameterizedProfileDef);
	Depth : IfcPositiveLengthMeasure;
	Width : OPTIONAL IfcPositiveLengthMeasure;
	Thickness : IfcPositiveLengthMeasure;
	FilletRadius : OPTIONAL IfcNonNegativeLengthMeasure;
	EdgeRadius : OPTIONAL IfcNonNegativeLengthMeasure;
	LegSlope : OPTIONAL IfcPlaneAngleMeasure;
 WHERE
	ValidThickness : (Thickness < Depth) AND (NOT(EXISTS(Width)) OR (Thickness < Width));
END_ENTITY;

8.15.3.13.8 References

IfcParameterizedProfileDef