Experimental and 3D Numerical Study on Time-Dependent Behavior of Stone Column–Supported Embankments

Abstract

In this study, laboratory model tests and three-dimensional (3D) numerical analysis were carried out on stone column–improved ground under embankment loading. In the experimental study, the time-dependent change in stress on the stone column and clay (at the embankment–ground interface) was measured for different spacing-to-diameter ratios. Finite-difference software was used for further investigation to measure the change in settlements, stresses, and pore pressures with time. In the numerical analysis, the stone column and the sand embankment were represented with the Mohr-Coulomb model, whereas the modified Cam-clay model was used for the soft clay. It was observed that to ensure no differential settlement on the embankment surface, a minimum embankment height of 2 times the clear spacing between the stone columns is necessary. The maximum lateral deformation of the stone column was observed at approximately 2.5 times the diameter of the column from the top.