CONSOLIDATION ANALYSIS AROUND A DRIVEN PILE IN SATURATED CLAY

A distribution formula of initial excess pore pressure is proposed with a modified cam-clay model and assumptions of plane strain conditions. This formula is compared with the adequate numerical method proposed by Cao and the formulation by Gibson. The governing equation of consolidation is derived, based on the elastic deformation of soil skeleton and continuity of fluid water. Thus an analytical solution is obtained through a variable separation approach combining established initial and boundary conditions, and this solution can be used as a theoretical foundation of deducing coefficients of consolidation in a pressuremeter test. A parametric study of dissipation of excess pore pressure is made, considering the effect of stress history and rigidity index. The results indicate that the normalized plastic radius and excess pore pressure decrease as the increasing of overconsolidation ratios. The dissipation of excess pore pressure around a pile runs fast at its early stage while slow at its late stage.