Updated Lagrangian large deformation analysis of consolidation settlement with finite element method for a case study in Iran

Settlement of fine-grained soils is often governed by a consolidation process which involves quite large strains. The classic, one-dimensional consolidation formula is based on the small strain theory, although it is still practically useful. Since strains are relatively large during the consolidation process, the overall behavior of the medium is geometrically nonlinear. In this paper, a coupled consolidation analysis was carried out to predict the consolidation settlement of ground beneath an embankment, as a case study, representing the feasibility of large strain consolidation analysis. It was followed by the development of a code in the MATLAB environment to solve the required equations, with further application to a case study in Iran. In addition, analyses were performed by one-dimensional conventional methods and compared with the results obtained by the finite element procedure. Predictions made by large deformation finite element analysis, in comparison to those obtained based on small strain assumptions and conventional methods, appeared to be more accurate, although the required computational effort was much higher, owing to frequent recomputation of the stiffness matrix.