Spatial Structure for infra models

[evandroAlfieri]

This issue is for tracking agreements and comments on the use of Spatial Structure (SS) for IFC4.3

Here are the questions that triggered the discussion in the IF:

• Is there a fix (standard) spatial structure for infra models, like the one for buildings?
  • No, there is no fix spatial structure
• Does this mean that file federation cannot be based on SS?
  • Probably. Or at least not only on SS

The ones below are all example of legit SS:

Example1

• IfcSite
  • IfcRailway
    • IfcRailwayPart (TRACK1)
    • IfcRailwayPart (TRACK2)
  • IfcBuilding
  • IfcBuilding
  • IfcBridge

Example2

• IfcSite
  • IfcRailway
    • IfcRailwayPart (TRACK1)
    • IfcRailwayPart (TRACK2)
    • IfcBuilding
    • IfcBridge
  • IfcBuilding

Example3

• IfcSite
  • IfcRoad
    • IfcRoadPart
      • IfcRoadPart
    • IfcRoadPart
      • IfcRoadPart
  • IfcBuilding
  • IfcBuilding
• IfcSpazialZone (parcel or lot)

[JanErikHoel]

IR-ROAD-WP3_ConceptualModelReport - Annex I - Example instance diagrams_2_0.docx

I believe this document should be the starting point for the discussion on the spatial breakdown for the road part of an infrastructure project. This is what we use as a guiding here at the Trimble Quadri team in Norway.

[JanErikHoel]

We here in the Quadri team try to build up the correct spatial structure for a infrastructure project consisting of terrain, some roads and some water and sewer systems with their corresponding alignments.

BUT in addition we have existing buildings, existing/planned trees etc. in the model (miscellaneous 2. order stuff).
How should we organize this in the spatial structure?

[SergejMuhic]

• No, there is no fix spatial structure

I cannot help looking at this as an oxymoron. A structure not being fix? Well then it is not a structure and another concept should be used to represent it. The definition of structure:

"Something made up of a number of parts that are held or put together in a particular way."