Seismic Response of Structure Isolated with Quintuple Friction Pendulum Bearing Under Directivity Focusing Earthquakes
Quintuple Friction Pendulum (QTFP) isolator having five effective pendula with nine stage sliding regimes operation is an extended technology of Triple Friction Pendulum (TFP) isolator. Because of its multiple sliding surfaces, Quintuple Friction Pendulum system shows highly adaptive behavior instead of being passive system. The paper describes nonlinear mathematical model and seismic response of a structure isolated with Quintuple friction pendulum bearing. Different configurations depending on displacement capacities, effective time period and effective damping are considered for a design of QTFP bearing. The seismic demand parameters like top floor absolute acceleration, base shear and isolator displacement have been studied. Further, to study a seismic behavior of QTFP bearing under a Directivity Focusing Earthquakes, total nine records including far-field, near-fault ground motion with directivity effect and fling step effect are considered. Depending on the directivity effect and rupture pattern, for a given earthquake event, the near-fault ground motions are highly variable from far-field ground motions. It is found that, due to backward and forward momentum conveyed by the directivity pulse, near-fault directivity effect imposes higher demand compare to fling step having forward momentum only.
KeywordsSeismic isolation Quintuple friction pendulum system Near-fault with forward directivity Fling step
- 8.Lee D, Constantinou MC (2015) Quintuple friction pendulum isolator-behavior, modeling and validation. In: Technical Report MCEER-15-0007, Multidisciplinary Center for Earthquake Engineering Research. University at Buffalo, Buffalo, NYGoogle Scholar
- 9.Galesorkhi R, Gouchon J (2000) Near-source effects and correlation to recent recorded data. In: Proceedings, 6th U.S. National Conference on Earthquake Engineering, Seattle, WashGoogle Scholar