The sub-regional scale: Garfagnana, Italy
Garfagnana is a mountain area in Toscana; with its own administrative and political powers corresponding to the sub-regional authority of the Comunità Montana della Garfagnana.
At the sub-regional scale, it is necessary to determine how the global system will face earthquakes and how, and if it will be able to overcome the crisis in its immediate aftermath. Therefore the analysis should not be limited to the performance of single buildings, but it should take into account also the behaviour of the economic system, infrastructures, and public facilities.
The prototype was used to produce three kinds of results:
Risk maps and scenarios have been produced, representing the expected damage to buildings in the area combining the seismic hazard, the induced physical hazard of landslides and the vulnerability of residential buildings and public facilities.
Vulnerability of residential buildings has been assessed adopting a mixed sampling-statistical method, as some settlements (Minucciano, San Romano, Castelnuovo and Piazza al Serchio) had been extensively surveyed in previous field work, and could be used as test sites.
As far as landslides are concerned, information on more than 1,300 mass movements had been collected by IRRS-CNR under a grant from Regione Toscana. The code to calculate slope stability was run to assess the number and the location of landslides that may be triggered by any earthquake with a predetermined value of PGA. On some slopes, where geometric, geological and geotechnical data were available at a greater level of detail and accuracy, a single slope analysis has been carried out. In this case, also groundwater conditions were accounted for more accurately, after extensive surveys and mathematical modelling. The generated scenarios forecast how an earthquake of given severity might trigger landslides, collapsing on settlements or on lifelines (or dragging them down the slope).
A demonstration of performance of social systems facing a damaging earthquake has been performed analysing the function of the health care system, according to the method that has been developed within the project. In order to assess the vulnerability of the health care system, the analysis has to be performed on a spatial basis, confronting the capacity for curing victims provided by each single hospital with the geographical basin from which it attracts patients in ordinary times and from which it could receive victims during extraordinary emergencies.
A first attempt to assess the vulnerability of the health care system has been carried out. Using the Network Analysis GIS function it was possible to estimate the time needed for injured to be taken to the closest hospital in Garfagnana.
SERGISAI - Contract Number: ENV4-CT96-0279 (DG 12 DTEE)
Project Coordinator: Gaetano Zonno
zonno@irrs.mi.cnr.it