Effect of rocking ground motions on floor acceleration response in non-isolated and isolated steel frame structures

In this study, the floor acceleration response of non-isolated and isolated steel frame structures to the single rocking component of the ground motion is examined. A shaking table test was conducted, with loading applied to both non-isolated and isolated cases. The results revealed that, under the rocking component, the acceleration of non structural components (NSCs) is related to the floor position. Calculating the response of NSCs with frequencies higher than the primary structure's fundamental frequency based solely on the top floor spectra is not conservative. For NSCs with frequencies above the primary structure's fundamental frequency, it is advisable to increase damping to prevent excessive responses. Additionally, comparisons reveal that seismic isolation technology does not provide effective protection for nonstructural components at all frequencies and may even increase the response of nonstructural components with higher frequencies. Therefore, isolators with higher damping should be chosen to mitigate these effects.