Analytical Solution for the Consolidation Behavior of Deep Cement Mixed Column–Improved Ground

Abstract

This paper presents an analytical solution for the consolidation behavior of deep cement mixed (DCM) column–improved ground on the basis of the equal strain condition. The proposed analytical solution accounted for the vertical permeability and rigidity of DCM columns and natural soil, stress transfer, and radial drainage. The solution was based on the theory of one-dimensional consolidation along with the equivalent vertical permeability and coefficient of consolidation. The analytical solution was first derived assuming equal permeability in both DCM columns and surrounding soil and then modified to include the radial drainage effects for the case with different permeabilities in DCM columns and natural soil. The performance of the proposed analytical solution was compared with the numerical simulations on the basis of FEM and an analytical solution found in the literature for the DCM column–improved ground. The proposed analytical model was also verified using physical model test results found in the literature for DCM column–improved soft Bangkok clay. The composite coefficient of consolidation of DCM column–improved ground can be predicted within approximately 5% error using the present analytical model.