Robustness of 3D base-isolated R.C. systems with FPS

This study evaluates the seismic robustness of 3D r.c. structures isolated with single-concave friction pendulum sys-tem (FPS) devices by computing the seismic reliability of different models related to different malfunction cases of the seismic iso-lators. Considering the elastic response pseudo-acceleration as the relevant random variable, the input data have been defined by means of the Latin Hypercube Sampling technique in order to develop 3D inelastic time-history analyses. In this way, bivariate structural performance curves at each level of the r.c. structural systems as well as seismic reliability-based design abacuses for the FP devices have been computed and compared in order to evaluate the robustness of the r.c. system considering different failure cases of the FP bearings. Moreover, the seismic robustness is examined by considering both a configuration equipped with beams connecting the substructure columns and a configuration without these connecting beams in order to demonstrate their effectiveness and provide useful design recommendations for base-isolated structural systems equipped with FPS.