Reliability-Based Stability Assessment of Natural Slopes

Slope failures are catastrophic in nature, resulting in widespread loss of lives and infrastructure. Consequently, stability analysis of slopes has gathered considerable attention by the research community across the globe. In practice, limit equilibrium approach forms the underlying principle for majority of the conventional slope stability analysis methods. One of the major limitations of the limit equilibrium methods is that they fail to account for inherent variability of in situ soil and its influence on the assessment of slope stability. As a contribution to this important aspect, the current study presents a reliability-based slope stability analysis of a natural slope of an infinite extent. The slope is analyzed in the following four states of the natural slope, namely, dry state, fully submerged state, with steady seepage, and under seismic loading. The reliability analysis is performed using Hasofer–Lind first-order reliability method. The in situ soil properties considered as variables include in situ soil cohesion, angle of internal friction, and unit weight. The analyses results are presented with respect to different levels of in situ soil variability, slope angles, depths of potential failure plane, and magnitude (and its variability) of seismic loading. Evidently, the study provided a better insight and different perspective into the stability analysis of infinite slopes.