Physical and geometric non-linear analysis using the finite difference method for one-dimensional consolidation problem.

Abstract

This article presents a numerical model based on the finite difference method for the physical and geometric non-linear analysis of a one-dimensional consolidation problem regarding a saturated, homogeneous and isotropic soil layer with low permeability and high compressibility. The problem is formulated by adopting the void ratio as the primary variable, considering a Lagrangian movement description. The physical non linearity is introduced on the formulation by the constitutive law defined as effective stress and permeability void ratio functions. Based on this numerical model, a computational system named AC-3.0 was developed, which has been verified and validated in terms of the temporal variation of the void ratio distribution throughout the soil layer, by comparing the numerical results with analytical and numerical solutions found in literature for some specific scenarios. Knowing the void ration distribution,it is possible to obtain secondary variables such as: superficial settlement, effective stress and excess of pore water pressure.The importance of the non-linear formulation is highlighted for the analysis of problems related to material presenting high compression and a very high initial void ratio.