Implementation and Verification of Real-Time Hybrid Simulation for the Dynamic Performance Assessment of Base-Isolated Structures

Real-time hybrid simulation (RTHS) is an economical and reliable method for the evaluation of structural dynamic performances, and the fixed analytical substructure model is often used in RTHS which may affect the accuracy of results. In this study, a real-time hybrid simulation platform (RTHSP) developed by configuring a generic National Instruments (NI) controller with hybrid programming strategy is presented in detail. The dynamic performances of a scaled base isolated structure, where the unscented Kalman filter (UKF) was used to update the analytical substructure Bouc–Wen model during the RTHSs was evaluated by presented RTHSP. RTHS of a base-isolated structure was performed where a lead rubber bearing (LRB) was tested physically as the experimental substructure of a part of the isolation layer and the superstructure with the rest of the isolation layer model updated by UKF was considered as the analytical substructure. Under the excitation of three natural earthquakes, the RTHSs with and without UKF updating were compared and analyzed the differences between the two. The results indicated that the displacements of experimental substructure generated by RTHS with UKF updating are the largest, while the relative displacements and acceleration of superstructure are the smallest overall, and the dynamic characteristics of the isolation layer of the analysis substructure updated by UKF are different from that without updated, which reflected the more authentic dynamic mechanical performance of the base-isolated structure under earthquake excitation. In addition, the RTHSP and the hybrid programming strategy are verified to be reliable in tests and experiments, and the components and implementation of a RTHSP for base-isolated structures is described in detail, providing a reference for research on RTHS method.