Seismic mitigation performance evaluation of linked buildings with a vibration-suppression layer

Abstract

Linked buildings (LBs) have been widely used in urban areas because of their aesthetic quality and versatility. As LBs are vulnerable to damage under earthquake excitation, undesired vibrations should be suppressed. The use of weak connections is an effective approach to improve the seismic performance of LBs; however, they are inapplicable to LBs with inherently strong connections. In this study, a novel control system—a LB with a vibration-suppression layer (LBVSL)—is proposed to reduce the seismic responses of the LBs with strong connections. The LBVSL system is implemented by introducing a vibration-suppression system into one of the buildings. To extensively investigate the seismic mitigation performance of the LBVSL, a parametric study is conducted to evaluate the trends of its mean vibration energy with the control and structural parameters based on a simplified calculation model. The control parameters include the equivalent stiffness and damping of the vibration-suppression system, and the structural parameters include the stiffness and mass of the LBs. To understand the damping effect of the LBVSL, several numerical examples are studied. The analytical results suggest that the LBVSL has substantially reduced vibration energy and responses compared to the plain LBs. For instance, the LBVSL with the optimal parameters achieves a vibration energy reduction of 69% and a stochastic seismic response decrease of 30–50% relative to those of plain LBs. Additionally, the LBVSL achieves better damping performance and robustness when the vibration-suppression layer is placed on a lower floor. Furthermore, the simplified model provides an alternative for effectively optimizing critical parameters in the preliminary design stage.