Probabilistic analysis of gyttja undrained strength from CPTU data for slope stability analysis

Abstract

The design of an artificial peninsula near Copenhagen led to an extensive experimental campaign where a significant number of CPTU tests were performed. The CPTU data presented a significant dispersion due to material heterogeneity, which motivated a probabilistic analysis of the soft soil undrained strength. For that purpose, a probabilistic density function of the undrained strength ratio was estimated and introduced as input in a limit equilibrium slope stability analysis. This enables the evaluation of the probabilistic density function of the factor of safety, the probability of failure and the reliability index instead of a single deterministic factor of safety. This information can be used by the designer or project owner to choose between different solutions based on the required level of risk. (c) 2022 the Author(s).