Probabilistic seismic slope stability assessment of geostructures

Typically, seismic analysis of large-scale geostructures, such as embankments, is performed by means of deterministic pseudostatic slope stability methods, where a safety factor based approach is adopted. However, probabilistic seismic fragility analysis can be a more efficient and realistic approach for interpreting more accurately the seismic performance and the vulnerability assessment of an earth structure. There are two major approaches for performing vulnerability analysis: either approximately assuming that the demand values follow a lognormal distribution or numerically most frequently using the Monte Carlo simulation (MCS) method, where the probability of exceedance for every limit state is obtained by performing MCS analyses for various intensity levels. The MCS technique is considered to be the most consistent reliability analysis method, with no limitations on its applicability range. The objective of this work is to present the efficiency of the MCS-based numerical approach versus the commonly used lognormal empirical approach for developing fragility curves of embankments.