How positions are given along a linear project: the distance along a named alignment (chainage or stationing) and the offset from it.
Stationing and chainage are two names for the same idea: locating a point on a road, railway or pipeline by its distance along a named alignment from a defined start, plus its offset to the left or right. North American projects call it stationing and write it in hundreds of feet; metric projects call it chainage and write it in kilometres and metres.
Chainage is how designers, surveyors and site teams talk about locations on linear works: a culvert at Ch 2+340, a signal at 12 m 40 ch, a pier at Sta. 5+10. Drainage schedules, earthworks quantities, possession plans and asset registers are organised by it. In IFC 4.3, positions can be referenced to an IfcAlignment, so models carry the same referencing.
Read the full entry on BIMpedia →
