from buildingSMART: The IfcRelAssociatesProfileProperties
is an objectified relationship between non geometric profile properties
(subtypes of IfcProfileProperties)
and elements to which these properties apply, e.g. building elements
and building element types as used within the structural engineering
domain for steel, timber or concrete structures.
If the ProfileSectionLocation
attribute is given, it points to a shape aspect of the geometric or
topological representation of the structural member. This allows the
assignment of several profile properties (by many instances of IfcRelAssociatesProfileProperties)
to accommodate varying profiles and members with different profile
If the ProfileOrientation
attribute is given, it provides an orientation of the profile.
- For IfcStructuralCurveMember
it is a rotation about the longitudinal axis of the underlying curve,
the x axis is determined by a line from the start vertex to the end
- If the longitudinal axis
is not parallel to the structural z axis of the structural coordinate
system of the analysis model, i.e. the curve member is a beam (or
non-vertical member), the ProfileOrientation
defaults to [0.,0.,1.] (if the z axis is not orthogonal to the x axis,
an adjustment is made to maintain orthogonality, see function IfcBuildAxes
for an algorithm). The β angle is then measured from the
structural z axis to determine the location of the structural z axis of
- If the longitudinal axis
is parallel to the structural z axis of the structural
system of the analysis model, i.e. the curve member is a column, the ProfileOrientation
defaults to [1.,0.,0.]. The β angle is then measured from the
axis to determine the location of the structural z axis of the profile.
- If the ProfileOrientation
attribute is given as an IfcDirection,
it would default to:
- For 'beams' as [0.,
sinβ, cosβ ]
- For 'columns' as
[cosβ, -sinβ, 0.]
HISTORY New entity
in Release IFC2x Edition 2.
Addendum 1 CHANGE The entity IfcRelAssociatesProfileProperties
has been made a subtype of IfcRelAssociates.
Edition 3 CHANGE The entity IfcRelAssociatesProfileProperties
has changed by adding the attributeProfileOrientation.
|| Profile property definition assigned to the instances.
|| Reference to a shape aspect with a single member of the ShapeRepresentations list. This member holds
the location at which the profile properties apply.
|| The provision of an plane angle or a direction as the measure to orientate the profile definition within the elements coordinate system.
- For IfcStructuralCurveMember the IfcPlaneAngleMeasure defines the β angle, for columns the derivation from the structural x axis and for beams the derivation from the structural z axis. The IfcDirection precisely defines the orientation of the profile's structural z axis within the structural coordinate system of the analysis model.
IFC2x Edition 3 CHANGE The attribute ProfileOrientation is a new attribute.
||SET [1:?] OF IfcRoot;