Model Exchange between Revit and Allplan using IFC: a Case Study for a Bridge Model

This report presents the process of exchanging BIM models between Allplan and Revit, in particular emphasizing the limitations of the modifiability of geometry. The report is based on two BIM models of a bridge at two different design stages provided by professional engineering consultancies. For the analyzed models, the desired design-to-design exchange using the IFC4 Design Transfer View which allows geometric modifications of a model after its hand-over to another design application could not be tested due to a number of reasons. Instead, in the Revit-to-Allplan exchange, the “IFC 2x3 Coordination 2.0 View” can be used. The exchange has shown that all the elements imported into Allplan could be made modifiable via control points. The exchange in the opposite direction (Allplan-to-Revit) shows that the piles modelled in Allplan as cylinders have proved to be the only objects which could be modifiable by control points in Revit. The other elements could not be modified because either Revit did not provide this possibility (in case of tessellated elements) or they were unable to maintain their shape while any attempt of geometric modification (in case of non-tessellated beams).