Research on the effectiveness of a new-type bearing for structural seismic and vibration dual control

Abstract

The burgeoning expansion of subway systems has heightened the significance of subway-induced vibrations and their impact on nearby structures. Addressing the dual challenges of mitigating subway-induced vibrations and ensuring structural seismic safety is garnering increasing attention. This study introduces a new-type seismic and vibration dual control isolation bearing that leverages the deformability of rubber. This bearing consists of a thick rubber bearing and a traditional horizontal rubber bearing, which are decoupled in motion and responsible for vertical vibration isolation and horizontal seismic isolation, respectively. A scaled model was constructed of an actual structure to assess the effectiveness of this bearing, conducting shaking table tests with inputs simulating typical subway-induced vibrations and seismic motions. Our findings reveal that the bearing successfully meets predefined isolation and vibration control objectives. Regarding subway-induced vibration loads, it markedly diminishes peak vertical acceleration responses. Frequency-wise, it effectively attenuates high-frequency responses while amplifying low-frequency ones. Notably, increasing damping does not significantly improve vertical vibration isolation. Regarding seismic loads, by aptly configuring the horizontal seismic isolation parameters, the bearing achieves targeted seismic isolation objectives. Furthermore, this new bearing demonstrates certain vertical isolation capabilities, distinguishing it from traditional horizontal rubber isolation bearings.