Numerical Evaluation of Adaptive Base-Isolated Structures Subjected to Earthquake Ground Motions

In this study, the seismic response of a scale-model, base-isolated, multistory structure is numerically investigated. At the isolation level, the structure is equipped with isolation bearings combined with adaptive (semiactive) fluid dampers. The behavior of the dampers is controlled according to an H∞ optimal feedback control algorithm which utilizes a fuzzy logic approach to establish weighting functions. Numerical simulations are performed to evaluate the dynamic response of the isolated test structure when different damping mechanisms (passive, semiactive, or active) are incorporated within the isolation system. The numerical simulations indicate that, in comparison to an isolation system with high passive damping, an isolation system with semiactive damping can be effective in simultaneously controlling the response of the structure while limiting the isolation system response.