adaptive curved surface slider for improved seismic protection

The new adaptive curved surface slider sip®-adaptive is a curved base isolator with two primary sliding surfaces and an articulated slider whereby the relative motions on both primary sliding surfaces are decoupled. this allows designing the two primary sliding surfaces with different friction coefficients and curvatures. one primary sliding surface is designed with lower friction to provide best structural isolation for the design basis earthquake and more frequent earthquakes with lower shaking level. the other primary sliding surface is designed with greater friction coefficient to provide high damping and increasing isolator stiffness at shaking levels of the maximum considered earthquake which reduces the total isolator displacement at this maximum shaking level. the sip®-adaptive is characterized by steady-state force displacement trajectories at different amplitudes and its isolation performance is assessed by non-linear time history analysis. the optimized double friction pendulum is used as benchmark isolator. the comparative study demonstrates that the sip®-adaptive improves the structural safety for all ground shaking levels without getting larger maximum isolator displacements. the experimental validation of the sip®-adaptive confirms its envisaged dynamic behaviour.