On the Response of Seismically Isolated Buildings Equipped with Quasi‐Zero Stiffness Device and Tuned Inerter Dampers

This study demonstrates that s eismically isolated buildings incorporating a q uasi‐zero stiffness device and t uned inerter damper (SQT) system mitigate displacement and acceleration responses, confirming the feasibility and robustness of this passive seismic control strategy. We propose design equations for the tuned inerter damper in an SQT system. To gain fundamental insights, we model the SQT system as a two‐degree‐of‐freedom system and examine it from both theoretical and experimental perspectives. A theoretical solution for sinusoidal excitation is derived to provide a general understanding. A shaking table test validates the theoretical solution and confirms the SQT system's effectiveness in damping the earthquake response. Close agreement between the numerical and experimental results indicates that the theoretical model accurately predicts amplitude‐frequency curves. The test results show that the SQT system limits the displacement response to be within the criterion and reduces the acceleration response to levels comparable to conventional seismic isolation under sinusoidal and earthquake excitations.