Definition from IAI: A vertical structural member which often is
aligned with a structural grid intersection. It represents a vertical, or
nearly vertical structural member designed to transfer loads to its base.
The quantities relating to the column are defined by the
IfcElementQuantity and attached by the
IfcRelDefinedsByProperties. The following quantities are foreseen, but
will be subjected to the local standard of measurement:
| Name |
Description |
Value
Type |
| CrossSectionArea |
Total area of
the cross section (or profile) of the column. The exact definition and
calculation rules depend on the method of measurement used. |
IfcAreaQuantity |
| ColumnVolume |
Total volume
of the column. The exact definition and calculation rules depend on the method
of measurement used. |
IfcVolumeQuantity |
HISTORY New entity in IFC
Release 1.0
ISSUE See issue log for changes made in IFC Release 1.5.1. See
issue and change log for changes made in IFC Release 2x.
Geometry Use Definitions:
The geometric representation of IfcColumn is given by the
IfcProductDefinitionShape, allowing multiple geometric representation.
Included are:
Local Placement
The local placement for IfcColumn is defined in its supertype
IfcProduct. It is defined by the IfcLocalPlacement, which defines the local
coordinate system that is referenced by all geometric representations.
- The PlacementRelTo relationship of IfcLocalPlacement shall point (if
given) to the local placement of the same IfcSpatialStructureElement, which is
used in the ContainedInStructure inverse attribute, or to a spatial structure
element at a higher level, referenced by that.
- If the relative placement is not used, the absolute placement is
defined within the world coordinate system.
Standard Geometric Representation using Swept Solid
Representation
The standard geometric representation of IfcColumn is defined using the
swept solid representation. The RepresentationType attribute of
IfcShapeRepresentation should have the value 'SweptSolid'. The following
constraints apply to the standard representation:
- Solid: IfcExtrudedAreaSolid shall be supported
- Profile: IfcRectangleProfileDef and IfcCircleProfileDef shall
be supported
- Extrusion: The profile shall be extruded vertically, i.e., in
the direction of the z-axis of the co-ordinate system of the referred spatial
structure element. It might be further constraint to be in the direction of the
global z-axis in implementers agreements. The extrusion axis shall be
perpendicular to the swept profile, i.e. pointing into the direction of the
z-axis of the Position of the IfcExtrudedAreaSolid.
EXAMPLE for standard geometric representation.
 |
The following interpretation of dimension parameter applies for
rectangular columns:
- IfcRectangleProfileDef.YDim interpreted as column width
- IfcRectangleProfileDef.XDim interpreted as column
height.
The following interpretation of dimension parameter applies
for round colums:
- IfcCircleProfileDef.Radius interpreted as column radius
|
Advanced Geometric Representation using CSG Representation
The advanced geometric representation of IfcColumn is defined using the
Swept Solid or CSG representation. The RepresentationType attribute of
IfcShapeRepresentation should have the value 'SweptSolid' or 'CSG'. The
following additional constraints apply to the advanced representation:
- Solid: see standard geometric representation,
- Profile: IfcRectangleProfileDef, IfcCircleProfileDef,
IfcIshapeProfileDef and IfcArbitraryProfileDef shall be supported.
- Extrusion: All extrusion directions shall be supported
- Boolean result: The IfcBooleanClippingResult shall be
supported, allowing for Boolean differences between the swept solid (here
IfcExtrudedAreaSolid) and one or several IfcHalfSpaceSolid.
EXAMPLE for advanced geometric representation.
 |
Use of a special profile type (here
IfcIshapeProfileDef) for the definition of the IfcExtrudedAreaSolid. |