Seismic Performance of Slopes: Do the Dynamic Features of the Landslide Matter?

Simplified methodologies for the seismic assessment of natural slopes are still in fervent development by virtue of their utility in large-scale assessment, that would be practically unfeasible through a more demanding advanced modelling. In this context, the present study describes a practice-oriented model, in which the Newmark displacement method is extended to include the following novel aspects: namely, considering the salient features of the multi-directional dynamic response of the landslide and the presence of a multi-component seismic excitation. The interpretative model is used for an extensive parametric study of the effect of the dynamic properties of the unstable mass on the slope performance, considering a variety of seismic scenarios and subsoil conditions. As a result, indications of practical relevance are pointed out, such as the correlation of the slope performance with some parameters characterising the ground motion and the importance of the frequency-dependent effects.