Italian accelerometric archive: geological, geophysical and geotechnical investigations at strong-motion stations

Abstract

Geological, geophysical and geotechnical investigations, for the characterization of the strong-motion recording sites managed by the Italian Civil Protection, have been carried out in the framework of the project "Italian strong-motion database in the period 1972-2004". The project aimed at creating an updated database of strong-motion data acquired in Italy by different institutions in the time span 1972-2004, and at improving the quality of disseminated data. This article illustrates the state of the recording site characterization before the beginning of the project, explains the criteria adopted to select the sites where geophysical/geotechnical investigation have been performed and describes the results of the promoted field surveys

The recording stations of the Italian strong motion network: geological information and site classification

“…The information for the RAN stations comes from different sources and was mainly collected during the Project S6 (Luzi et al 2010). Geologic 1:100,000 scale maps were made available for most of the ITACA stations, in order to have a minimum and uniform level of geologic information, since the standardization of information for all stations was one of the primary objective.…”

“…Among them, 7 stations that recorded the 1976 Friuli earthquake (Fontanive et al 1985) and 16 stations of the 1980 Irpinia event (Irpinia Project: Palazzo 1991a,b) have been deeply investigated by geological and geotechnical data, including laboratory and in situ tests; for the 1980 Irpinia event ENEL forms, as well as geologic maps at 1:5,000 scale with corresponding geologic cross-sections were also provided; • seismic velocity profiles obtained by using the controlled source spectral analysis of surface waves (SASW) for 18 sites that recorded the 1997-1998 Umbria Marche earthquake sequence (Kayen et al 2008); • stratigraphies, versus profiles, seismic refraction profiles and geotechnical parameters for about ten digital stations come from the Project S6 (Luzi et al 2010). …”

“…Profiles for a total of 52 sites were extracted from literature (e.g., Luzi et al 2010), all investigated by means of down-hole or cross-hole tests. The information from literature derives from: (1) investigations at selected instrument sites that recorded the 1976 Friuli and 1980 Irpinia earthquakes; (2) microzonation and other studies for local municipalities or regions; and (3) site studies by consulting engineers and geologists.…”

“…it), which this issue of the Bulletin of Earthquake Engineering is devoted to. Referring to Pacor et al (2011) for details about the development of ITACA within two projects, S6 and S4, funded by the Italian Department of Civil Protection (DPC), from 2006 to 2010, we will illustrate in this paper the studies made in the latter project (S4) to improve the previous catalogue of geological, geotechnical and geophysical information of strong motion stations, prepared within Project S6 (Luzi et al 2008(Luzi et al , 2010.…”

Extensive characterization of Italian accelerometric stations from single-station ambient-vibration measurements

“…9 Comparison between f 0 from microtremor and from 1D modeling at accelerometric stations for which a noise measurement and an independent shear wave velocity profile down to the bedrock are available. The following geophysical tests were conducted for each station: CLF, down-hole (Di Giulio et al 2006); SELE, down-hole (Capilleri et al 2005); AQV, MASW and cross-hole (Luzi et al 2010 (Bozzano et al 2000); ARN and BGI, cross-hole (ISMES, 1992; Progetto Irpinia, Allegato 6; NERIES Project, http://www.neries-eu.org/)…”