Nonlinear consolidation model of composite foundation with partially penetrated stone column: Fid-Bau Portal

Nonlinear consolidation model of composite foundation with partially penetrated stone column

Ya-dong, Zhou / Qi-dan, Zheng / Shuai-jie, Guo

Abstract A nonlinear consolidation model for composite foundation with partially penetrated stone column is established based on the piece-linear finite difference method. This model allows for consolidation analysis of composite foundation with partially penetrated stone column under both free strain and equal strain conditions, while accounting for self-weight of stone column and soil layer, smear zone, well resistance effect, attenuation of additional stress along the depth direction, and the nonlinear variation of compressibility and permeability during the consolidation process. A calculation program was developed in Fortran, and the model was validated. The numerical solution of the average degree of consolidation obtained from the present model under equal strain condition is slightly smaller than the existing analytical solution, but overall it agrees well with the FEM result and the simplifying solution. Under both free strain and equal strain conditions, the numerical solutions of the excess pore water pressure obtained from this model and the FEM results are in good agreement. The nonlinear consolidation characteristics of composite foundation under different strain conditions were investigated, and the influence of penetration ratio, C c/C k and column diameter ratio on the average degree of consolidation and average settlement were further analyzed through numerical examples.