Analytical solutions for one-dimensional nonlinear large strain consolidation of soft soils with high compressibility under a multi-stage loading

At present, many achievements have been made in the analytical theory of large strain consolidation. However, the consideration of nonlinearity of compression and permeability is not yet sufficient. In this study, a large number of compressibility and permeability test data have been investigated to verify the advantages of log-log relationships in describing nonlinear characteristics of compressibility and permeability of soft soils under both large strain and small strain, and the variation range of parameters in log-log relationships are also presented. Also, based on the log-log relationships, a one-dimensional nonlinear large strain consolidation model of thin soft soil layer is established by considering excess pore pressure as a variable, and the analytical solutions of the consolidation model are obtained under three conditions, respectively. Then, the reliability of analytical solutions is verified by comparing with the results observed in the field and degenerate solution, respectively. Finally, the influence of loading method, final load, compressibility and permeability parameters on consolidation behavior are analyzed. This study provides theoretical supports for the calculation of nonlinear large strain consolidation of actual soft soil layer.