Significance of spatial variability of strength properties of deep cement mixed columns on the stability of embankments

Abstract

The research work presented in this thesis begins with a study on the post-yield strain-softening behaviour of isolated DCM soil specimens. The consolidation behaviour of DCM soil specimens was numerically simulated using a strain-softening incorporated constitutive model. The results indicated that the numerical model can accurately predict the performance of DCM soil beyond yielding. Then the behaviour of highway embankments improved using DCM technique and loaded in the post-yield region was simulated using 3D and 2D numerical models. The conversion into a plane-strain model based on the equivalent area approach was identified as the best approach to simplify a 3D problem when DCM columns experience post-yield softening. Next, the efficiency of different DCM column configurations on preventing post-yield softening and improving the performance of embankments constructed on soft soil deposits was investigated. DCM wall type improvement, individual DCM columns arranged in a square pattern, individual DCM columns arranged in a triangular pattern, T-shaped DCM columns and application of geosynthetic reinforcement were evaluated under this section.

Date of Award	2018
Original language	English