Stochastic Response of Hybrid Base Isolation Systems based on Energy Measures

In this work, we extend a previously developed numerical model for the seismic response of a base isolation system comprising rubber dampers and friction sliders, to include stochastic energy measures. The said model is a trilinear, five-parameter hysteretic model in conjunction with a single-parameter Coulomb slider that has been calibrated using experimental evidence. More specifically, we now employ Monte-Carlo simulations to investigate the effect of variations in the numerical values of the six-parameter model on the response of the hybrid base isolation system. The calibrated parameters values from the experiments are used as mean values, while the standard deviation for each parameter is deduced from the identification tests employing best-fit optimization for each experiment separately. TheMonte-Carlo simulations show that material parameter variations produce a non-stationary effect in the response of the base isolation system thatcan be traced by the time evolution of the standard deviation of various energy measures computed at different time intervals.