caa a22 4500 445846984 CHVBK 20180317145402.0 cr unu---uuuuu 170323e20110601xx s 000 0 eng 10.1007/s10518-011-9263-5 doi (NATIONALLICENCE)springer-10.1007/s10518-011-9263-5 Site effects "on the rock”: the case of Castelvecchio Subequo (L'Aquila, central Italy) [Elektronische Daten] [S. Marzorati, C. Ladina, E. Falcucci, S. Gori, M. Saroli, G. Ameri, F. Galadini] The April 6, 2009 L'Aquila earthquake was responsible for an "anomalous”, relatively high degree of damage (i.e. Is 7 MCS scale) at Castelvecchio Subequo (CS). Indeed, the village is located at source-to-site distance of about 40km, and it is surrounded by other inhabited centres to which considerably lower intensities, i.e. Is 5-6, have been attributed. Moreover, the damage was irregularly distributed within CS, being mainly concentrated in the uppermost portion of the old village. Geophysical investigations (ambient seismic noise and weak ground motions analyses) revealed that site effects occurred at CS. Amplifications of the ground motion, mainly striking NE-SW, have been detected at the uppermost portion of the carbonate ridge on which the village is built. Geological/structural and geomechanical field surveys defined that the CS ridge is affected by sets of fractures, joints and shear planes—mainly roughly NW-SE and N-S trending—that are related to the deformation zone of the Subequana valley fault system and to transfer faults linking northward the mentioned tectonic feature with the Middle Aterno Valley fault system. In particular, our investigations highlight that seismic amplifications occur where joints set NW-SE trending are open. On the other hand, no amplification is seen in portions of the ridge where the bedrock is densely fractured but no open joints occur. The fracture opening seems related to the toppling tendency of the bedrock slabs, owing to the local geomorphic setting. These investigations suggest that the detected amplification of the ground motion is probably related to the polarization of the seismic waves along the Castelvecchio Subequo ridge, with the consequent oscillation of the rock slabs perpendicularly to the fractures azimuth. Springer Science+Business Media B.V., 2011 Site effects nationallicence Rock sites nationallicence Spectral ratios nationallicence Ambient seismic noise nationallicence Structural characteristics nationallicence Jointing conditions nationallicence Geomechanical analysis nationallicence 2009 L'Aquila earthquake nationallicence Central Italy nationallicence Marzorati S. Centro Nazionale Terremoti Sede di Ancona, Istituto Nazionale di Geofisica e Vulcanologia, Strada Cameranense 1, 60131, Passo Varano, AN, Italy aut Ladina C. Centro Nazionale Terremoti Sede di Ancona, Istituto Nazionale di Geofisica e Vulcanologia, Strada Cameranense 1, 60131, Passo Varano, AN, Italy aut Falcucci E. Sezione di Roma1, Istituto Nazionale di Geofisica e Vulcanologia, Rome, Italy aut Gori S. Sezione di Roma1, Istituto Nazionale di Geofisica e Vulcanologia, Rome, Italy aut Saroli M. Dipartimento di Meccanica, Strutture, Ambiente e Territorio, Università di Cassino, Cassino, Italy aut Ameri G. Sezione di Milano-Pavia, Istituto Nazionale di Geofisica e Vulcanologia, Milan, Italy aut Galadini F. Sezione di Roma1, Istituto Nazionale di Geofisica e Vulcanologia, Rome, Italy aut Bulletin of Earthquake Engineering Springer Netherlands 9/3(2011-06-01), 841-868 1570-761X 9:3<841 2011 9 10518 https://doi.org/10.1007/s10518-011-9263-5 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10518-011-9263-5 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Marzorati S. Centro Nazionale Terremoti Sede di Ancona, Istituto Nazionale di Geofisica e Vulcanologia, Strada Cameranense 1, 60131, Passo Varano, AN, Italy aut NATIONALLICENCE 700 1- Ladina C. Centro Nazionale Terremoti Sede di Ancona, Istituto Nazionale di Geofisica e Vulcanologia, Strada Cameranense 1, 60131, Passo Varano, AN, Italy aut NATIONALLICENCE 700 1- Falcucci E. Sezione di Roma1, Istituto Nazionale di Geofisica e Vulcanologia, Rome, Italy aut NATIONALLICENCE 700 1- Gori S. Sezione di Roma1, Istituto Nazionale di Geofisica e Vulcanologia, Rome, Italy aut NATIONALLICENCE 700 1- Saroli M. Dipartimento di Meccanica, Strutture, Ambiente e Territorio, Università di Cassino, Cassino, Italy aut NATIONALLICENCE 700 1- Ameri G. Sezione di Milano-Pavia, Istituto Nazionale di Geofisica e Vulcanologia, Milan, Italy aut NATIONALLICENCE 700 1- Galadini F. Sezione di Roma1, Istituto Nazionale di Geofisica e Vulcanologia, Rome, Italy aut NATIONALLICENCE 773 0- Bulletin of Earthquake Engineering Springer Netherlands 9/3(2011-06-01), 841-868 1570-761X 9:3<841 2011 9 10518 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer