Simplified evaluation of seismic vulnerability of Lisbon Heritage City Centre based on a 3DGIS-based methodology

The seismic characterization of buildings plays a fundamental role in Portugal since a considerable percentage of the building stock is vulnerable to this phenomenon. It provides reasonable measures which helps to minimize and mitigate the consequences of an eventual seismic event. The paper presents a 3DGIS-based methodology to assess the building seismic vulnerability, based on geometric, structural and material properties for each building, with a focus on the Pombalino buildings. For that purpose, in the first step the data provided by national institutions were organized and stored in a GIS database and applied to build the 3D model, in a procedural modelling approach, and then a simplified seismic risk evaluation methodology was developed and applied to the heritage Lisbon city centre. The followed methodology proved to be very efficient at an urban scale, allowing an easy identification of the vulnerable buildings and the viewing of the surrounding geometries, assisting the interpretation of their spatial distribution. A more detailed study will imply the in situ data collection to calibrate the estimative of fundamental period and to identify structural changes against the officially registered, which are crucial to develop the real assessment of the seismic vulnerability.