Development of Sloped Rolling-Type Isolation Devices for Seismic Protection of Important Equipment and Facilities

Development of Sloped Rolling-Type Isolation Devices for Seismic Protection of Important Equipment and Facilities

In this study, the dynamic behavior and design requirements of the multi-roller isolation devices with an inbuilt sliding friction damping mechanism are theoretically investigated. In addition to having a good potential to control the acceleration response transmitted to the protected object as a steady level, the multi-roller isolation device has a better stability performance and better re-centering capability than the conventional single-roller isolation device. Moreover, the inbuilt sliding friction damping mechanism facilitates to effectively suppress excessive displacement responses and to promptly stop rolling motion after earthquakes. Based on the analytical result, a simplified twin-flag hysteretic model is proposed to represent the hysteresis loop of the multi-roller isolation device.