Beam

Definition

Geometry

Geometry type	Extrusion	Profile	Segments	Clipped	Slanted
BoundingBox
Extruded solid	Linear	Rectangular	1	No	No
Extruded solid	Linear	Arbitrary	1	No	No
Extruded solid	Linear	Curved	1	No	No
Extruded solid	Linear	Rectangular	1	Yes	No
Extruded solid	Linear	Arbitrary	1	Yes	No
Extruded solid	Linear	Curved	1	Yes	No
Extruded solid	Linear	Rectangular	1	No	Yes
Extruded solid	Linear	Arbitrary	1	No	Yes
Extruded solid	Linear	Curved	1	No	Yes
Extruded solid	Linear	Rectangular	1	Yes	Yes
Extruded solid	Linear	Arbitrary	1	Yes	Yes
Extruded solid	Linear	Curved	1	Yes	Yes
Brep

• Not slanted in the context of beams means, that the extrusion is horizontal relative to the direction of the global Z-axis
• As the basic representation beams should always have a bounding box. The bounding box can be used as a place holder for beams with complex geometry in programs that are not able to support the given geometry. This could be the case e.g. in programs that don't support slanted beams, beams with an arbitrary profile or Brep representation.
• Beams that are horizontal or slanted and have a constant profile along the entire length of the beam are transferred using an extruded solid
  • The extrusion profile may be rectangular, arbitrary or curved.
• Beams may be clipped, but they should not be clipped to change the profile of the beam.
• Beams may not have holes in them, not even using the opening element.
• As a further restriction round (with a circular profile) beams are not supported using solids. Round beams appear mostly in steel constructions as part of a more complex grid of beams and this kind of beams is best represented using Brep geometry.
• There is no specific support for steel profiles in IFC R2.0. Steel profiles can be represented using a arbitrary profile (polyline) and by specifying the type of the steel profile as a string.
• When solids are used for the beam geometry the exchange files are more compact and it is easier to derive quantities from the beam geometry. It is also easier to map to the most common beam types (e.g. rectangular beam) used in programs.
• In all other cases the representation is made using Brep geometry
  • Beams with a round profile
  • Curved beams
  • Beams with a varying profile
  • Beams with a profile that can't be expressed by IfcCompositeCurve. The vocabulary of the composite curve contains the following elements: straight segment, circular arc and elliptical arc
  • Beams with holes

View considerations

• Arch. design >> Quantities take off / cost estimating
  • Beam quantities (length / profile) from geometry

Used by views

• Arch. design >> Quantities take off
• Arch. design >> Thermal load calculations / HVAC system design
• CAD / visualization

Data structure

IfcBeam
GlobalId
OwnerHistory
Owner history [all]
Label
UserDefinedType
PartOfGroups
Grouping [1,2]
IsContainedBy
Containment [all]
RelatingObject
Building storey [all]
IsDefinedBy
Dynamic property assignment [all]
RelatingPropertyDefinition
PropertySet system [all]
HasProperties
Common beam properties [1,3]
LocalPlacement
Relative placement [all]
PlacementRelTo
Building storey [all]
Representations
Geometric representation [all]
Items
Bounding box geometry [all]
Extruded solid: rectangular [1,3,5]
Extruded solid: arbitrary [all]
Extruded solid: curved [1,2,3,5]
Extruded solid: rectangular, clipped [3,5]
Extruded solid: arbitrary, clipped [3,5]
Extruded solid: curved, clipped [3,5]
Extruded solid: rectangular, slanted [3,5]
Extruded solid: arbitrary, slanted [3,5]
Extruded solid: curved, slanted [3,5]
Extruded solid: rectangular, clipped, slanted [3,5]
Extruded solid: arbitrary, clipped, slanted [3,5]
Extruded solid: curved, clipped, slanted [3,5]
Brep geometry [3,5]
Classification
Classification assignment [none]
Classifications
Classification [none]
calcBeamSectionArea
calcBeamVolume

Uses concepts

Bounding box geometry [all]
Brep geometry [3,5]
Building storey [all]
Classification [none]
Classification assignment [none]
Common beam properties [1,3]
Containment [all]
Dynamic property assignment [all]
Extruded solid: arbitrary [all]
Extruded solid: arbitrary, clipped [3,5]
Extruded solid: arbitrary, clipped, slanted [3,5]
Extruded solid: arbitrary, slanted [3,5]
Extruded solid: curved [1,2,3,5]
Extruded solid: curved, clipped [3,5]
Extruded solid: curved, clipped, slanted [3,5]
Extruded solid: curved, slanted [3,5]
Extruded solid: rectangular [1,3,5]
Extruded solid: rectangular, clipped [3,5]
Extruded solid: rectangular, clipped, slanted [3,5]
Extruded solid: rectangular, slanted [3,5]
Geometric representation [all]
Grouping [1,2]
Owner history [all]
PropertySet system [all]
Relative placement [all]

Used by concepts

Building storey

Copyright © 2000-2002 BLIS-Project [BLIS, Registered Organization]
Author: Jiri Hietanen (jiri@blis-project.org)
All rights reserved.