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Novel self-lubricating materials are currently being proposed to be used in sliding isolation systems such as the curved surface sliding isolator system, or pendulum bearing system, for the protection of buildings and structures. The current codes for anti-seismic devices are focused on the evaluation of the performance of the whole isolation system; as a consequence, a reliable procedure for the pre-assessment of the material combinations of sliding interfaces is currently missing. Therefore in this paper, an experimental methodology is proposed for the characterization of self-lubricating materials through tests on small-scale specimens performed using customized equipment able to reproduce the operational conditions\ud of real isolation systems as per contact pressure, sliding velocity, temperature and slide path. The testing sequence has been designed in order to evaluate the sliding properties of the material in terms of static and dynamic coefficient of friction and wear resistance. Examples are reported for the assessment of two self-lubricating materials with different sliding characteristics.\ud In order to validate the method and to confirm the reliability of extrapolating the results to real working conditions, prototypes of pendulum isolation systems incorporating the assessed materials have been tested according to North American specifications and the relevant dynamic properties assessed from the Horizontal Load—Displacement loops. The experimental outcomes confirmed\ud that the frictional characteristics provided by the proposed procedure can be reliably used in the design of seismically isolated structure

The re-centring capability is recognized as a fundamental function of the isolation system, because it is intended to\ud prevent substantial permanent deformation at the end of the earthquake that may affect the serviceability of the\ud structure and eventually limit the capability of the isolators to withstand aftershocks and future earthquakes. In this\ud study, the re-centring behaviour of isolation systems composed of sliding bearings with curved surfaces is investigated\ud in shake-table tests carried out on a one-storey steel frame with rectangular plan, scaled at one third-length\ud scale and isolated with four bearings. The coefficient of friction of the bearings is varied by changing the material\ud or lubrication condition of the pads, providing different equivalent damping ratios to the isolation system. The\ud response of the base isolated structure to selected natural ground motion waveforms is assessed in terms of the\ud residual displacement after a single event and the accrual of displacements during a sequence of quakes, and\ud considerations on the influence of the coefficient of friction on the re-centring behaviour, as well as on the effect\ud of an initial displacement offset are drawn. The re-centring provision of the current European design code is\ud eventually checked against the experimental data

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