Valutazione degli effetti sismici locali in siti associati a singoli edifici: un nuovo strumento schedografico “geologico”

Abstract

The seismic response to an earthquake is correlated to the seismic source, to the propagation of the seismic waves and to the local lithologic and morphologic characteristics. To better understand the role of the geologic and morphologic conditions affecting the seismic shaking, it is necessary to perform a simple and standard characterization of the site, through the knowledge of the “on site” and bibliographic data. A new geological form has been performed, finalized to obtain a collection of the geologic, geomorphologic, geotechnical and geophysical characteristics of the studied sites. This form, if enough data are available, allows a quantification of the expected amplification effects, using the simplified methodologies of the recent national and regional codes (NTC, 2008; Conferenza delle Regioni e delle Province Autonome – Presidenza del Consiglio dei Ministri, 2008; Regione Lombardia, 2008). These evaluations permit to synthesize the qualitative and quantitative “geologic” information of the form in an unique parameter used in civil engineering. The new “geologic” form can be used during an earthquake, considering the three different phases: prevention, emergency and reconstruction, to support the vulnerability and damage forms performed for the different structural typology of the buildings. The “geologic” form can be considered as a basic tool for seismic risk studies.