ABSTRACT Nonstructural components are instrumental in maintaining the post‐earthquake functionality of buildings. However, many such components behave like freestanding rigid blocks that are highly susceptible to overturning under pulse‐like ground motions, posing the risks of economic losses and casualties. With the growing demand for seismically resilient buildings, the protection of nonstructural components has become a critical concern. Previous studies have primarily focused on translational excitations acting on freestanding blocks, and the influence of high‐rise and multi‐dimensional isolated structures, which exhibit pronounced rotational effects under seismic excitations, on the freestanding blocks has rarely been reported. To address this issue, this study investigated the influence of structural rotation on the overturning of freestanding blocks. Finite element simulations were conducted to quantify the contribution of such rotations; this was followed by the development of a dynamic model of the rocking bodies by incorporating structural rotation. The model was validated using shaking table tests and numerical simulations. Finally, the overturning acceleration spectra under one‐sine pulse excitation were derived. The results indicate that structural rotation increases the overturning limits of a block in the low‐frequency regime. Conversely, at larger frequency ratios ω p / p , it renders the blocks more prone to overturning.
Tang et al. (Fri,) studied this question.