Influential factors on the performance of embankments stabilised on deep-mixed columns

The realistic estimation of the hydromechanical response of embankments on soft clay, stabilised with lime-cement columns, relies heavily on the accurate modelling of both in situ clay and the columns of the three-dimensional (3D) problem. This study simulates the 3D effects using a homogenisation technique, while the quantification of the most influential parameters governing the stress–strain response of the stabilised clay is assessed through the Design of Experiments (DOE). The governing mechanisms in relation to the full range of model parameters for various stabilisation ratios and length configurations, including end-bearing and floating columns, are investigated. Subsequently, to reduce the costs originating from the use of lime and cement and the associated anthropogenic greenhouse gas emissions, the key relationship between column length, stabilisation ratio and relative stiffness between the clay and columns is explored. The proposed systematic approach enables efficient incorporation of sensitivity studies and reduces computational demand in the design phase, enabling optimisation.