| Large deformation consolidation theory is complicated because of its material, geometry and seepage nonlinearity. Some analytical solutions were got on the basis of many hypothesizes, which might result in misunderstanding of the essence of consolidation. With the development of technology and needs of understanding of consolidation, it is necessary to do more researches on the mechanism of nonlinear consolidation. Based on the large number of data of compression test and triaxial test, analytical and numerical work of consolidation of large deformation were carried out considering the effect of complicated nonlinear characteristics, and the parameters analysis of the consolidation equation were also presented. At the same time, considering soil damage and failure mechanisms, the process of stone column formation under dynamic loading was analyzed by virtue of finite element software such as ABAQUS and PLEXPDE, growth and dissipation of excess pore pressure were simulated during the stone column invaded into soft soil layers. These main contents are included in this paper.(1) Different coordinate system results in different expressions of stress and strain definitions. The expression of strain is different between Eulerian coordinate system and lagrangian coordinate system, which would affect calculatinr results of settlement and consolidation degree during consolidation of soil, and furthermore affect accuracy of prediction. The paper analyzed the nonlinear relationship between effective stress and void ratio in different coordinate system. Continuity condition of large deformation consolidation theory was studied. The material derivation of strain rate of eulerian description for large deformation consolidation theory was compared with the strain rate defined in small deformation consolidation theory, the result showed that there existed differences in these two description systems.(2) Based on the test data of Ningbo soft soil, differences were studied between one dimensional large deformation consolidation and small deformation consolidation fordifferent ratio of compression index and permeability index C_c /C_k. It was found that it's convinient to get an analytical solution when C_c/C_k is 1.0, but in other cases, the gonverment equation can only be soluted numerically. Self weight may affect the consolidation characteristics obviously.(3) The consolidation coefficient and permeability coefficient were investigated, the monotonicity of consolidation coefficient with the void ratio and other factors also studied, variation law of hydraulic gradient was introduced during the consolidation process. Consolidation process can be divided into four stages in the view of variability of hydraulic gradient. The effects of poisson's ration, boundary condition, compression modulus and permeability coefficient were studied by using of FEM.(4) Soil particles sedimentation was a part of consolidation process, under the assumption that the effective stress is zero on the deposition layer, the variation law of interface between water and suspension and interface between suspension and deposition was analyzed, the density and void ratio change with form of shock wave, which can be explained by using shock model theory.(5) Dynamic consolidation of large deformation was a more complicated dynamic phenomenon, which was lack of comprehensive theoretical and numerical studies. However, it's necessary to give a quantitative analysis result with the growth of dynamic compaction engineering in coastal areas. Soil would be damaged, softened and failure under impact loading, then the stone column invaded into these area. The soil characteristics was discribed by using of damage mechanism, the process of stone column invaded into soft soil layers was simulated using dynamic explicit method. The excess pore pressure changed drasticly when the stone column invaded into soft soil layers, variation law of the excess pore pressure was simulated with pseudo-static method during the formation of stone column.
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