SEISMIC PERFORMANCE OF BRIDGES EQUIPPED WITH FPS

The scope of the present study is focused on the evaluation of the seismic response of bridges iso-lated by single concave sliding pendulum isolators (FPS) for the different structural properties when the presence of the rigid abutment is considered or neglected (i.e., isolated viaducts). In this way, they have been defined two specific multi-degree-of-freedom (mdof) models to simulate the elastic behavior of the reinforced concrete pier in combination to the infinitely rigid presence of the deck and to the presence of the rigid abutment if considered. Both the numerical models also account for the non-linear velocity-dependent behavior of the FPS bearings. Considering the alea-tory uncertainty in the seismic input by means of several natural records with different character-istics, a parametric analysis is developed for several structural properties. The relevant results ex-pressed as the statistics in non-dimensional form with respect to the seismic intensity have permit-ted to study the differences between the two numerical models in relation to the effectiveness of the seismic isolation.