Geotechnical Parameters of Landslide-Prone Laflamme Sea Deposits, Canada: Uncertainties and Correlations

Abstract

Due to inherent variability arising from unpredictable geological depositional and post-depositional processes, the geotechnical parameters of Laflamme sea clay deposits remain highly uncertain. This study aims to develop and apply a methodology to assess the uncertainties of geotechnical parameters using statistical distributions for a landslide-prone Saguenay Lac-Saint-Jean (SLSJ) region. We used the measured physical and mechanical parameters of Laflamme Sea clays of various locations in the SLSJ region to characterize the geotechnical parameters in a representative manner. Goodness-of-fit tests assign each physical and mechanical parameter a distribution function for their descriptive analysis. We found that the quality of these tests is significantly influenced by outliers. The detected outliers in the dataset considerably impact the distribution type and the uncertainties of the specific geotechnical parameter. Subsequently, appropriate distribution functions for each parameter were assigned after treating the outliers. The derived coefficient of variability values for the SLSJ region were significantly high in comparison to the literature with cone penetration test data being only the exception. Finally, the results indicated that the uncertainties of geotechnical parameters of the Saguenay-Lac-Saint-Jean region marine clays are high as compared to Scandinavian clays and are relatively comparable to other eastern Canadian clays.