Development of an IFC-based data schema for the design information representation of the NATM tunnel

A tunnel data schema employing the New Austrian Tunneling Method (NATM) is proposed to efficiently manage and exchange the design information of road tunnels between different computer environments. The data schema was developed by extending the Industry Foundation Classes (IFC) used as standards in Building Information Modeling/Model (BIM) projects. The design guidelines and tunnel drawings were analyzed in order to apply the design information of the NATM road tunnels. From the analysis results, the applicable IFC elements were identified through a comparative analysis with the existing IFC data schema, and new items were defined for the additional necessary elements. The newly defined elements were classified into the parts representing the information of the space occupied by the tunnel and that representing the information on components such as shotcrete, steel ribs, and concrete linings. The applicability of the developed schema was examined by using it to construct an experimental environment, in which information modeling was possible.