Failure behavior analysis of embankment built on soft subgrade

The need to build embankments on soft clay deposits is widespread, including railway and expressway embankments. The difficulties in constructing embankments on these deposits are well known. The permeability of soft subgrade is usually low, so that construction is generally performed under undrained conditions, as a consequence of the low undrained shear strength of soft clay. The classical design of an embankment is often based on a limit equilibrium approach, in which the deformation factor can not be taken into account, so that the finite element method which can take deformation and stability into account becomes an effective method. Based on the in situ test data of Lianyungang railway embankment built on soft subgrade, the failure behavior and limit height of embankment are analyzed under the plane strain condition by using large deformation finite element method and Mohr-Coulomb model. And the numerical results analyzed by finite element method are compared carefully with the in situ test data. The results show that the limit height and failure behavior of embankment can be obtained by using the large deformation finite element method.