Una scheda “geologica” per la valutazione degli effetti sismici locali nei siti di ubicazione di edifici: primi risultati della sperimentazione

Abstract

The seismic response to an earthquake depends on the genesis and propagation of the seismic waves and on the local lithologic and morphologic characteristics. To understand the influence of the geology on the seismic shaking, it is necessary to characterize the site in a standard and easy way, performing a field surveys and collecting bibliographic information. Therefore, a specific geologic form has been carried out, being able to storage the geologic, geomorphologic, geophysical and geotechnical information of the site. This data allow to have a quantification of the expected amplification effects through the introduction of the amplification factor. This geologic form can be integrated considering the different knowledge level of the recent regional and national seismic codes. Its use gives evaluations of the first level, using the qualitative data; evaluations of the second level using all the data and the relative amplification factor; these collected data can represent a base knowledge for the study of the third level. A first test has been performed on 72 sites, characterized by the presence of churches damaged by the earthquakes of Irpinia-Basilicata (1980), Abruzzo-Molise (1984) and Molise (2002).