Mandel–Cryer Effect in Vacuum Consolidation—a Numerical Study

Abstract

Dissipation of pore water pressure during vacuum consolidation is a complex phenomenon and is not uniform about the soil stratum. It is rapid near the drainage boundaries and becomes gradual with the distance away from the drainage boundary. However, it is observed from coupled deformation studies that pore water pressure undergoes an initial rise between the two drainage boundaries before they finally decrease. This excess rise in pore water pressure due to the application of external load is called as Mandel–Cryer effect. Because of possible experimental errors and ramp nature of loading in the field, this effect is difficult to be captured in situ. Besides, the dependency of this effect on Poisson’s ratio (v) of soil mass has been cited in the literature. To have a better understanding of this behaviour under vacuum pressure, a 2D numerical study has been conducted and the influence of Poisson’s ratio on the change in pore water pressure and horizontal displacements under vacuum pressure is discussed in this paper.