Seismic Protection of the Goddess of Morgantina Statue Through an Innovative Base-Isolation Device: Validation by Shake-Table Tests

Abstract

Monuments and historic structures have been extensively damaged by major seismic events that occurred in the Mediterranean area in the last decades. A large research activity has been devoted to the mitigation of seismic effects in historic buildings, but also the museums contents deserves the attention of scholars due to their inestimable values and cultural significance. In particular, statue-like objects revealed a poor dynamic behaviour during past earthquakes and are prone to overturn if seismic excitations overcame an acceleration threshold. In scientific literature a lot of analytical research are present in non-linear dynamic field but experimental works in this area still remain limited. In this research work, the results of an extensive test campaign, aiming at characterizing the dynamical behaviour and assessing the seismic protection level of an innovative bidirectional base-isolation device is presented and commented. The isolator consists in a series of multiple articulated quadrilateral mechanism elements, patented as KSJ (Kinematic Steel Joint), that allows the free movements of a rigid base in both horizontal directions, providing pendulum-like behaviour and re-centring capabilities. Shake-table tests on a full-scale replica of the statue of the Goddess of Morgantina have been carried out at the L.E.D.A. Research Institute at the Kore University of Enna, with varying load conditions, acceleration time-histories and intensities.