BIM/IFC-files As Input For 3D Land Administration Systems

Abstract

The growth of cities and the pressure on land worldwide leads to more complex and multilevel structures with different space interrelations. For the registration of complex spaces mostly 2D Land Administration Systems (LAS) are used, while a representation of space in 3D could provide a clearer insight. Concurrently, technological advancements rapidly improve methods to collect, create, visualise, register, store and disseminate 3D data. In this context, much research is now being carried out at the sources and data used as input in 3D LAS and the various methods for their collection. In this scene, the approach to reuse data from the design phase is gaining ground. Specifically existing Building Information Models (BIMs), usually encoded in the non-proprietary Industry Foundation Classes (IFC) format (ISO 16739-1:2018, 2018) are considered a promising source for 3D LAS. Previous research has shown promising results using BIMs as input for 3D LAS. However, the use of IFC-models from practice has not yet been tested adequately. This research investigates the technical issues that are encountered when using real-world IFC-models as input for the registration of apartment rights in a 3D LAS and how that process can be improved. In the context of this thesis, IFC-models are iteratively being validating against technical requirements. Five real-world IFC-models are collected. They are validated on the existence of IfcSpace, the ability to relate the IFC-model to the LAS, the validity of geometries, spatial relations i.e. overlap, and the ability to georeference the IFC-models. The results of these validation show that the collected IFC-models lack the ability to be georeferenced. Additionally most IFC-models did not contain IfcSpace, or a relation to essential attributes for identifying legal units in the Dutch 3D LAS. Recommendations and guidelines are formulated to address these issues. The IFC-models are placed in a 3D LAS at a conceptual level, in which the legal spaces are enriched with information of the Rights, Restrictions and Responsibilities (RRR's) to those spaces in line with the Land Administration Domain Model LADM)(ISO 19152:2012, 2012). For this a mapping between IFC and LADM is made. The results of this thesis include the set of validations and its derived recommendations and guidelines. Additionally a conceptual 3D LAS is made, which consists of a PostgreSQL database, which is LADM compliant, and is visualised in 3D tiles using a Cesium web viewer.