Experimental Investigation on Energy‐Based Semi‐Active Response Control Strategy for Base‐Isolated Structures

ABSTRACT An experimental investigation on the semi‐active response control of a smart base‐isolated structure equipped with a magnetorheological (MR) damper is presented. The experiment is conducted considering a single‐story superstructure, whereas the isolation system comprises a sliding mechanism and linear springs used as restoring devices. Importantly, the base‐isolated structure is equipped with an MR damper installed at the isolation level. The force‐deformation behavior of the MR damper is characterized experimentally, and the modified Bouc‐Wen model is used to represent the behavior numerically. The energy‐based predictive (EBP) algorithm is used as a control law to dictate/modulate the control action effected by the MR damper. The smart base‐isolated structure is mounted on a unidirectional shake table and studied under earthquake ground motions. The results of the shake table tests conducted on the smart base‐isolated structure are presented and compared with those of the numerical simulations. The results of the fixed‐base and passively‐isolated models are also presented. The findings of the study validate the practicability of the proposed semi‐active control strategy to mitigate the dynamic response of base‐isolated buildings. Moreover, the results of the experimental investigation demonstrate the merits of the EBP algorithm in mitigating excessive peak isolator displacement and residual isolator displacement under earthquakes.