PSI - Issue 44

Marco Furinghetti et al. / Procedia Structural Integrity 44 (2023) 1490–1497 Marco Furinghetti / Structural Integrity Procedia 00 (2022) 000 – 000

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according to a recent research work on the topic (Furinghetti 2022); the aim of the present work is to apply such design procedure and to validate results through the analysis of the experimental outcomes of hybrid earthquake simulations, with an additional comparison to the peak response returned by purely numerical Non-Linear Time History Analyses. As a first step, the minimum considerable design period has been evaluated, by computing the period value which corresponds to the intersection point between the damped response spectrum of the isolated system and the capacity curve of the fixed-base building, normalized with respect to the building mass, as shown in Fig. 2.

Fig. 2. Minimum design period for the base-isolated building

A minimum value of 2.0 sec for the design period has been detected, by adopting a significantly high value of equivalent viscous damping, aiming at considering high frictional properties. More specifically, experimental hybrid tests have been performed by considering a full-scale device as a physical substructure, tested at the EUCENTRE Laboratory in Pavia (Italy),and therefore the reference performance point of the isolation system has been calibrated, in order to obtain the actual friction coefficient and equivalent radius of curvature of the physical device itself. In Fig. 3 the tested device is shown as picture (left) and 3D rendering section (right).

Fig. 3. Tested full-scale device: picture (left) and 3D rendering section (right)

The full-scale physical isolator consists of a Double Curved Surface Slider isolator (Constantinou et al. 1990, Constantinou et al. 1999, Dolce et al. 2005, Kumar et al 2015), with an internal non-articulated slider (Fenz and Constantinou 2006, Castaldo and Amendola 2021a, Castaldo and Amendola 2021b). Both the sliding surfaces have the same radius of curvature (1600mm), with the inner slider height equal to 120mm: the resulting value of