ROTATIONAL EFFECTS PRODUCED BY THE Mw 6.3 2009 L’AQUILA EARTHQUAKE. A review on how the seismological, geological, topographical and geomorphological factors can influence the occurrence of earthquake-induced rotations

Abstract

The Mw 6.3 2009 L’Aquila earthquake produced an impressive number of rotational effects on vertically organized objects such as chimneys, pillars, capitals and gravestones. The complete dataset of such effects consists of 120 observations at 39 different sites and represents a compendium of earthquake-induced istances of rotational effects that is unprecedented in recent times. In this work we focus on 49 objects that rest directly on the ground and are not affected by rotational modes of the underlying structure, and can be more reliably considered as representative of pure rotational ground motion. We look for possible relationships between the distribution of the observed rotations and the macroseismic effects of the earthquake, and try to recognize and evaluate which geological and seismological parameters can be significant contributors to local rotations.