The constitutive relation uses the linear elastic model for the upper part of the embankment. The calculation parameters set up for the finite element model of embankment mainly involves E, μ and γ. E is the elastic modulus of materials, μ is the Poisson’s ratio, γ is the weight of soil. The subgrade can be divided into two layers. Upper loess layer is Q3 loess, about ten meters. The lower layer is Q2 loess, can be regarded as a relatively stable hard layer, deformation amount is very small. The upper Q3 loess layer basic constitutive relation is the ideal elastic-plasticity model, E is the elastic modulus, μ is Poisson ratio, c is cohesion, φ is internal friction angle. The constitutive relation of the lower part of hard loess layer can be regarded as linear elastic model, calculation parameters reference to the embankment. The calculation parameters of subgrade bottom layer see for Table 1. The calculation parameters of embankment see for Table 2.