Evaluation of topography site effect in slope stability under dynamic loading

Abstract : The slope topography site effect is a phenomenon in which the seismic ground motion is amplified at the crest of the slope. This effect can damage structures and can even cause slope instabilities. The aim of this study is to explore the impact of slope geomorphology parameters on topographic site effects. A dimensionless factor, the ratio of the slope height to the seismic wavelength is identified as a critical parameter. Numerical simulations resulting in the seismic response of a uniform slope in an elastic material to excitation of vertically propagating SV waves, allowed defining the effects of these parameters to amplification factors and extension of the affected zones. In civil engineering, the knowledge of zones which will experience amplified excitation is important and essential for the structural design. In particular, the vicinity of the crest is a zone frequently affected by strong amplifications, and in some cases, earthquake-induced landslides may occur. For this reason, graphs derived from the results of numerous numerical analyses, can be useful to predicting the maximum amplification factors, the area as well as the dimension of the amplified zone in the vicinity of the crest.