The new approx. 21 km long section between Köstendorf and Salzburg is one of the last major milestones in the upgrading of the Salzburg–Vienna rail corridor to four tracks. The section comprises a multitude of different civil engineering structures, posing high demands on the interdisciplinary design team. The open sections of the alignment require many over‐ and underpasses and road diversions. In addition, the majority of the section runs underground through the Flachgau Tunnel, which has the particular feature of a tunnel bridge. The aim of the BIM project is to provide a software‐independent, integrated model of the whole project. All parties involved in the project collaborate to define the LOD for the terrain, existing building, land use and geological models, as well as the models for the proposed new infrastructure for the open section, tunnels, ventilation control building, bridges, civil structures and drainage. The LoD are defined in parallel with the AIA according to the KISTE infrastructure identification system used by ÖBB (Austrian Federal Railways). At the same time, the BIM execution plans are generated by the team and adapted to the new BIM processes. The opportunities provided by the element‐based display and evaluation are anticipated to lead to considerable improvements in the field of interdisciplinary design and visualisation studies. The present article describes the current state of work and provides a preview of future developments.

An essential part of the Koralmbahn line, the Granitztal tunnel chain with a length of about 6.1 km runs between the Lavanttal and the Jauntal valleys and crosses the Deutsch Grutschen, the Granitztal and the Langer Berg. In early 2016, Austrian Railways ÖBB made a decision for the Granitztal tunnel chain project, which was then already under construction, to test the 3D model‐based Building Information Modelling (BIM) design method in addition to conventional 2D design. One essential precondition for the application of the BIM method on transport infrastructure projects was recognised as the required data structures. In addition to the definition of general project requirements and standards for BIM, work started on the structuring and classification of the construction elements required for the tunnel structure and their properties. Of equal importance are the spatial positioning and location of the construction elements and the definition of topological relationships to each other. The article gives an insight into the current state of development of BIM data structures for tunnel structure and track superstructure at the ÖBB and is intended to make a contribution to initiating the development of such data structures by all the disciplines involved in tunneling and transport infrastructure. The prime intention is to provide the BIM data structures produced in this way as an active contribution to the further development of the open BIM standard IFC (Industry Foundation Classes) in the IFC Underground Construction Group at buildingSMART