Probabilistic and fuzzy reliability analysis of a slope in Aliano (Basilicata, Italy)

Stability assessment is a geotechnical problem characterized by many sources of uncertainties. Some of them are the variability and the uncertainties in soil parameters determination. Coming from a correct geotechnical site characterization, only a complete approach to the subject lead to perform a significant stability analysis. The purpose of the present paper is to demonstrate how to correctly model data uncertainty in order to perform stability analysis with a good significance degree. Once determined input data, a probabilistic stability assessment (FOSM and Monte Carlo analysis) is performed to obtain the variation of failure probability with correlation coefficient between soil parameters varying. A first result is the demonstration of stability of FOSM (normal and lognormal distributions) and MC solutions, combing from a correct uncertainty modelling. Secondary the paper presents a simple algorithm (FFOSM), which use a fuzzy based analysis applied to data processing