Finite Element Analysis On Large Deformation Consolidation Of Soft Soil Based On The Biot's Theory

In this paper,the large deformation consolidation problem of the recent deposition of soil and blowing fill soft soil with high water content is studied, based on the basic principles of continuum mechanics and Biot consolidation theory. Control equations are established and used to solve the non-linear numerical solution with finite element method, ABAQUS software is used to compute and analyse the results described in different methods, the results are compared with the results of small deformation consolidation.There are total Lagrangian description (referred to as TL), updated Lagrangian description (referred to as UL), Eulerian (referred to as E) and Arbitrary Lagrangian Eulerian description (referred to as ALE) derived from above in Continuum mechanics descripting the movement of objects.This paper reflects the different large deformation consolidation problem of soil with different discription method.Referring to the derivation of Biot small deformation process, consolidation equilibrium equation and the flow continuity condition equation is solved, which is described such as in increments with stress and strain and increment rate expression and the use of stress and strain rate rate-based representation,while in the derivation of balance control equation process, the Galerkin weighted parameter method and variational method of virtual work principle are used. On the use of rate-balance equation, time domain with difference format is discreted;On the control equation of continuous flow conditions, space and time domain is discreted by Garlerkin weighted residual method and the finite difference scheme, thereby the large deformation finite element equations of consolidation is established.In the ALE method, the basic equations, mesh update program, and the variable convection problem are discrussed.The specific consolidation problem using different description and the constitute theroy of soil is analysed by ABAQUS software.The result is compared with small deformation consolidation and the settlement of foundation,lateral displacement distribution,pore water pressure dissipation solved by different method are discussed.