FEM Analysis Of Soil Anisotropy On Behaviours Of Road Embankment

The real soil is anisotropic soil, there are two kinds anisotropic soils. One is inherent anisotropy, the other is induced anisotropy. The former was mainly due to the particles arrayed differently between the horizontal and vertical direction in deposition. The latter mainly due to soil in all directions on the stress suffered different, resulting in soil particles are different in space. How to reflect the soil anisotropy on the behaviour of embankment is a focal problem.At first, the author study the compression of the shanghai soft soil, analysis the impaction of soil mechanical behavior resulting from the soil fabric anisotropy. The conclusions are that the shanghai soft soil has obvious anisotropy and the compression is different in different directions. Secondly, by using the elastic cross-anisotropic FEM, this paper systematically analyzes the influence of the horizontal parameters' values on the consolidation behavior of subgrade under embankment loading. Again, this paper introduce three kinds of elasto-plastic constitutive models. They are Modified Cam Clay (MCC), Three-dimensional Modified Cam Clay (3DMCC) and Anisotropic Three-dimensional Modified Cam Clay (ANISOTROPIC). And compose the FEM procedures, verify the procedures which are feasible by using the drained and undrained condition. Then use the procedures in calculating on the behaviour of embankments, get a series of conclusions, and compare the elastic analysis and elasto-plastic analysis on the behaviour of embankments. At last, with the MOMIS database, analysis the method of FEM in selection, and focus on the soil anisotropy on the behaviour of embankments.At the end of this paper, the problems concerned in this dissertation requiring further studies are discussed.