Influence of interactions between topographic and soil layer amplification on seismic response of sliding mass and slope displacement

Abstract

In the conventional evaluation of earthquake-induced displacement of slopes, the two-dimensional (2D) full-slope amplification as a result of the interaction of topography, soil layer and seismic ground motion is commonly neglected. To investigate this coupling effect on the evaluation of sliding displacements of earth slopes, linear and non-linear seismic response analyses are conducted on slope models with different inclinations and potential sliding mechanisms, subjected to simplified wavelets and recorded earthquake ground motions with various frequencies and amplitudes. The equivalent acceleration time histories of the sliding masses and the induced sliding displacements are derived. The results indicate that the soil layer amplification generally dominates the overall seismic response of the sliding mass. The controlling factors include the fundamental natural period of the soil deposit, the geometry of the sliding mass, the slope inclination, and the normalized depth of the sliding mass. Predictive models for the equivalent seismic ground motions of sliding masses are developed by including the 2D full-slope responses. Finally, an example application is presented to estimate the seismic response of the sliding mass and the slope displacements by using the proposed model.