Dynamic testing of variable friction seismic isolation devices and isolated systems

Within the scope of the SERA project (Seismology and Earthquake Engineering Research Infrastructure Alliance for Europe), at the EUCENTRE Foundation laboratories, component testing of innovative variable friction seismic isolation devices was performed through the dynamic hybrid testing technique and the EUCENTRE Bearing Testing System.

The main focus of the project is to observe the dynamic response of the isolated system under uniaxial seismic excitation as well as inherently varying axial loads on the variable friction devices. The validation of the proposed concept was performed through preliminary characterization tests following an EN15129-like type testing protocol, then moving to seismic tests once satisfactory preliminary results were obtained. In parallel, an improved definition of ground motion intensity measures (IMs), particularly in near-fault conditions and corresponding hazard-compatible record selection procedures for friction based isolation devices was discussed. Finally, numerical models have been calibrated based on the tests results to predict the single isolator and the whole system response.

The research leading to these results has received funding from the European Community’s HORIZON 2020 Framework Programme [H2020-INFRAIA-2016–2017/H2020-INFRAIA-2016–1] for access to EUCENTRE Laboratories under grant agreement n° 730900-SERA project and from the Italian Ministry of Education, University and Research (MIUR) in the framework of the “Departments of Excellence” (grant L 232/2016).