Effect of uncertainties in soil data on settlement of soft columnar inclusions

This paper deals with the assessment of settlements of soft columnar inclusions when uncertainties in soil properties and geometric features are considered. Two common design methods, the analytical homogenisation method and the finite element method, are then combined with Monte Carlo simulations in order to find, using probability distributions of soil and geometrical characteristics, the probability of settlements exceeding a given value. The results show that length and modulus of granular piles are the two major sources of uncertainty and that the model uncertainty obtained from the interpretation of relevant sensitivities is smaller with the finite element model. From the outcome, this paper demonstrates that when geotechnical uncertainties and their effects on soil responses are appropriately accounted for, they can lead to an improved understanding and modelling of a practical geotechnical problem such as the ground improvement by columnar inclusions.

► Soil settlement with inclusions is analysed following an uncertainty approach.
► Statistical analysis of soil data of a real site is used to characterise uncertainty.
► Two design methods, the analytical homogenisation and the FEM, are used.
► Granular piles modulus and length are two most significant sources of uncertainty.
► Simple uncertainty approach can be useful in providing convincing risk evaluation.