On the Importance of a Complete Characterization of Site Investigation Data Uncertainty: A Computational Example

Abstract

This paper studies the effect of (not) accounting for the systematic uncertainty in the characterization of soil parameters in spatially variable soils and the influence this has on the calculated probability of failure. Not fully accounting for systematic uncertainty is considered as an incomplete characterization of the uncertainty in site investigation. An example slope in a spatially variable soil is modeled, using a combination of subset simulation with the random finite element method. The relationship between uncertainty in the mean shear strength and probability of slope failure is then used to demonstrate that even small levels of systematic uncertainty can have a significant effect on the calculated probability of failure, which potentially increases by several orders of magnitude