From data to 3D digital archive: a GIS-BIM spatial database for the historical centre of Pavia (Italy)

摘要

Historical city centres are called to be witnesses of the past while supporting modern life. The competing needs for conservation and transformation involved in their development introduce a complex and multidisciplinary problem, which can be handled only by using proper tools. In this framework, the definition of shared digital archives able to collect and organize heterogenous data is believed to be the first step for the creation of an effective knowledge base, capable of activating analyses and supporting decision-making processes. The study presented here starts from the discussion of the requirements that an information system on historical centres should meet, and proposes a workflow based on the interoperability between GIS (Geographic Information System) and BIM (Building Information Modeling) aimed at the realization of a spatial relational database founded on CityGML. The OGC (Open Geospatial Consortium) standard was chosen in view of its capacity of representing the objects with their geometrical, topological and semantic properties, by specifying their relationships in a hierarchical environment. With the idea of introducing a repeatable model, the whole process starts from easily retrievable data on the city and makes use of standard data models, classification systems, programming languages and, as much as possible, of open software and contents. In order to test and validate the process the case study of the historical centre of Pavia (Italy) is presented as an experiment at the urban scale, while a single historical building complex is modelled for the assessment of the compliance to higher Levels of Detail. The workflow used to manage and display the information employs Visual Programming Language (VPL) and follows a four stages process: the retrieval of the input data, the informative modelling (GIS or BIM), the conversion in CityGML and the inclusion in the relational database. As a result, a three-dimensional spatial relational database in a standard data model is defined, capable of harmonizing, storing and organizing building information on historical city centres.