An IFC-based database schema for mapping BIM data into a 3D spatially enabled land administration database

There are different processes in 3D urban land administration in which spatial analysis plays an underpinning role. Among 3D data models, Industry Foundation Class (IFC) provides the potential capabilities for modelling legal and physical dimensions of urban properties. However, performing spatial analysis using IFC files cannot address the on-demand spatial analysis requirements of 3D urban land administration. In response to this limitation, 3D data needs to be stored in a spatial database to enable spatial analyses required by different stakeholders. Therefore, in this paper, by considering spatial analysis requirements in 3D-enabled urban land administration, an IFC-based database schema is designed. Moreover, a methodology for transforming Building Information Modelling (BIM) data into the proposed schema is provided. This methodology includes seven steps: designing the architectural model and adding legal data, georeferencing, IFC data validation and cleaning, mapping process, database data validation and cleaning, spatial analysis, and visualisation. To demonstrate the feasibility of the proposed database, three datasets are implemented in the database. Moreover, a new method for modelling legal spaces with oblique structures and two applications of spatial analysis in 3D urban land administration are provided.