Effects of Spatial Variability on Consolidation of Soft Soil Stabilized by Prefabricated Vertical Drains

Abstract

The conventional deterministic approaches for analysis of soil consolidation by prefabricated vertical drains (PVDs) assume a single best estimate of the degree of consolidation based on "average" soil properties used to define an "equivalent" homogeneous soil, leading to unreliable and uneconomical solutions. In this study, a stochastic approach is proposed to investigate the effects of soil spatial variability on the consolidation of a soft soil stabilized by PVDs. The approach uses the random field theory and Monte Carlo technique to generate thousands of random fields of spatial permeability coefficients that have the same underlying statistics. Each random field is then used to perform finite element analysis for the calculations of soil consolidation by PVDs, and the statistics related to the obtained degrees of consolidation are used to develop probabilistic analyses. The observations made from this study provide insight into the uncertainty associated with soil spatial variability and its impacts on the consolidation process.