Abstract: It's more prone to bending damage for the embankment supported with rigid pile composite foundation in soft soil areas under the action of seismic loads, even leading to serious damage and other serious consequences. The pile-soil interaction and the subgrade failure under the action of seismic loads were simulated by the discontinuous layout optimization (DLO) method. Also, the characteristics of deformation and load transfer between piles and soil and failure mechanisms of the piles and embankment were studied with different quantities and embeded depths of piles, and different quantities or distribution of higher stiffness piles. The results showed that the numerical results were similar to the ones of the model test. Under the action of the same seismic loads, the closer the piles to the center of the embankment was, the lower the bending moment of piles was. The bending failure of piles appeared more easily than shear failure. Under the seismic action, progressive failure would occur more easily between piles below embankments.