Numerical Stability Analyses of Embankments Supported on Deep Mixed Columns

Abstract

Deep mixed columns are used to support rapidly constructed embankments that would otherwise experience instability or excessive settlement. Column design is based, in part, on considerations of embankment stability, but limit equilibrium methods of slope stability analysis are not adequate because they only address composite shearing and not other failure modes, such as bending and tilting, that can be more critical. Numerical methods are necessary to address these failure modes. An example embankment was analyzed using limit equilibrium procedures and numerical methods. Both two- and three-dimensional numerical analyses were performed. The results demonstrate that limit equilibrium methods are not safe and that two-dimensional numerical analyses closely approximate the three-dimensional numerical analyses of the example embankment.