Dynamic responses of non-isolated and base-isolated building structures adjacent to slope under seismic excitation

Abstract

Building structures adjacent to slopes are common in urban and rural areas. These structures face more severe challenges under earthquake excitations, necessitating a study on the dynamic responses of building systems adjacent to slopes. Accounting for soil-structure interaction, viscoelastic artificial boundaries, and soil material nonlinearity, a three-dimensional numerical model of base-isolated structures adjacent to slopes was established. This study investigated the differences in seismic responses between structures at the slope toe and crest, compared the performance of aseismic and base-isolated structures, and analyzed the influence of seismic wave types. Results for the analyzed 10-story frame structure on a 45° slope indicate that structures at the slope crest generally exhibit larger peak floor accelerations, displacements, and inter-story drift ratios (IDRs) than those at the slope toe. Base isolation significantly reduces IDR discrepancies between crest and toe structures for the considered configurations. Near-field ground motions generally induced larger floor acceleration responses in the superstructure, whereas far-field ground motions tended to produce larger soil displacements and more pronounced plastic slip zones within the slope. Base isolation substantially mitigated the structural acceleration and deformation responses in the studied cases. These findings provide case-specific insights into the coupled slope-isolation-seismic mechanisms. Generalization to other structural types, slope geometries, and soil conditions requires further systematic parametric investigations.