Remote sensing as a tool for vulnerability assessment

In this paper it will be presented how the use of remotely sensed images can be of substantial help in evaluating the seismic vulnerability of sites for which in-situ data are scarce and not easy to collect. In the case under consideration a vulnerability study was started over a large industrial plant in the gulf of Siracusa, Sicily, southern Italy. A number of issues hindered collection of constructive information on structures and infrastructures found in the site (tanks, ducts, pipes, chimneys, streets, other structures), necessary to complete the assessment. Remote sensing was chosen as an alternate way to derive the missing information. QuickBird images at 0,61 m Ground Sampling Distance (GSD) were purchased over the area of interest and processed using dedicated software formerly developed within the Remote Sensing Group at Pavia. The software is a growing suite of general-purpose routines, integrated with new, specific features on the occasion of this work. It has allowed determining location, footprint, height of critical structures (such as tanks and chimneys), directly providing results in a format compatible with standard GIS formats. Such compatibility allowed remarkable savings on the time required to develop a GIS of the analysed area, which is a very useful tool for vulnerability and risk analysis.