Towards the 3D cadastre: GIS-BIM integration for 3D information management of the city of Cehegín

Nowadays, the zero land consumption European directives and the ever-increasing multi-story building construction due to urbanisation activities are highlighting the limitations of the bidimensional cadastre. From this context, the 3D cadastre could make a key contribution to managing the future built environment and cities. In this framework, the thesis aims to understand the potentialities of the 3D cadastre and proposes a methodology to ease its generation through rapid mapping techniques. Italy and Spain have been analysed as case studies, and it emerged that they have yet to develop their own and complete 3D cadastres. A deep investigation and study of one of the most advanced in Europe, the Netherlands, has been therefore carried out. Nevertheless, it is important to consider that the transition from 2D to 3D cadastre will increasingly be based on the BIM-GIS integration, in which the main data are usually derived from high-resolution 3D data of the urban scenarios, through photogrammetry and LiDAR techniques. Due to the compelling necessity for the public administration to update the land register, the following thesis will thus present a methodology focused on the development of a flowing 3D model of a building block located in a historical city centre of Spain: Cehegín. This is achieved by the BIM-GIS integration and using the iPad Pro low-cost LiDAR sensor combined with UAV (Unmanned Aerial Vehicle) point cloud data to create a geometrical model. The outcome is then combined with survey data gathered from a visual analysis conducted during the site survey and cadastral data that was retrieved from the official website to create an informative model. Levels of detail also ensure a faithful representation of the case study; as a consequence, the methodology has been divided into different phases based on them. A further goal of this research is to step from the 2D to the 3D cadastre in a time-effective manner. The solution of using the iPad Pro has been investigated since it can produce rapid 3D scanning with reduced time and costs of the operations during the site survey. The results prove that the iPad Pro produced a highly detailed point cloud but up to a certain height and without georeferencing, which has leaded to a necessary integration and georeferencing respect to the point cloud derived from the drone. Moreover, the level of detail obtained during the process it is equal to LOD3. However, some interoperability problems were found during the integration of cadastral data in the BIM model imported in GIS software. The causes of these criticalities, which led to a partial inclusion of the cadastral data in the BIM model, can be found within the exchange formats and the limitations of multipatch in GIS software. Our hope is that these results and considerations will establish the groundwork for future investigations.