Abstract
Cliff-attached constructions are buildings that are directly connected to and aligned with the vertical faces of mountains. The building is built with its backs on the cliff. Due to its complex grounding relationship, structural stress and deformation characteristics differ from conventional structures, so the SSI effect must be considered. Long periods, extended durations, and rich low-frequency components relative to ordinary ground vibration characterize long-period ground vibration in the far field. For a seismic isolation-type structure with a long period, it is especially complicated to consider the SSI (soil-structure interaction) effect, which needs to be explored in depth. On this basis, two structural configurations are established for analysis: the cliff-attached inter-story isolated structure and the double-story isolated structure. A comparison of these arrangements is conducted both with and without considering the impacts of soil-structure interaction. An examination of the extent of influence from regular earthquakes and far-field long-period earthquakes on the cliff isolation structure is performed under three-dimensional ground motion stimulation. The results suggest that the seismic reaction of cliff isolation structures to far-field long-period earthquakes exceeds that of conventional earthquakes. Particularly evident under three-dimensional ground motion conditions, notably during far-field harmonic-like seismic events, and the response is particularly significant. When factoring in the Soil-Structure Interaction (SSI) effect, it becomes apparent that the response of the cliff-attached structure is most pronounced when situated atop a soft soil foundation. As the soil stiffens, the damping efficacy of the double-story isolated structure decreases, though it continues to outperform the inter-story isolated structure. In addition, accounting for the SSI effect enhances the seismic response of cliff-attached isolation structures, especially in part connected to a mountain body that experiences obvious stress concentration and deformation, which should be thoroughly addressed during the structural design process. The improved stability of the double-story isolated structure's isolation bearings enables effective mitigation of tensile stress within the bearings, thus alleviating the problem of excessive tensile stress, and at the same time reducing the risk of the high-rise structure toppling under rare earthquakes.