Effects of Changes in Geometry on The Linear Elastic Consolidation Deformation

Abstract

Linear elastic finite consolidation deformation analysis has been made to investigate the effects of changes in geometry on a plane strain embankment problem in a subsiding ground below the water table. A theoretical formulation is presented for the consolidation of a linear elastic soil foundation subject to finite deformations. With the use of the Green-Naghdi effective stress rate in the linear rate type constitutive equation, a finite element solution is obtained based on the Updated Lagrangian scheme. Since the traction boundary is continually modified as the deformation proceeds, the traction force is treated by dividing into two components: the force due to static water pressure and the force due to embankment load. The deformation characteristics, including one dimensional consolidation, are discussed with comparisons of infinitesimal deformation theory. Geometry change affects the ground rigidity, giving stiffened time-settlement response during consolidation and reduced lateral deformations when compared with the infinitesimal deformation theory. The load concentration effects, which come from the changes in traction boundary geometry, can reduce the extent of stiffened time-settlement response even to a lower magnitude than in infinitesimal case. The lateral deformations at the embankment toe are always lower than that the infinitesimal case. Unlike an elasto-plastic material, the deformation behavior for an elastic material is independent of the loading history and dependent only on the magnitude of the load non-linearly.