Abstract: In order to study the coordinated mechanism of subgrade scattered piles in soft soil subgrade, we put forward the synergistic model of subgrade scattered piles, as the compensation for soft soil foundation. We also clarified slope ratio of boundary load and hard-shell correlation mechanism of critical loading of soft soil foundation by using Mathematica software, and established the checking method of bearing capacity of the synergistic subgrade scattered piles, that based on critical loading of soft soil foundation through theoretical analysis. The instance analysis of the spacing between scattered piles associated with its length-designing verifies the feasibility of the method for checking the bearing capacity of the foundation piles in the soft soil foundation that is compensated by subgrade scattered piles. It further reveals the failure mechanism that the unfavorable terrain at the passive area of the roadbed scattered piles aggravates its destabilization. The results show that the proposed synergistic model and checking method for the bearing capacity of the foundation piles have good applicability in embankment. and the paper also proposes the necessity of overload preloading scheme that should be used with caution, emphasizes the importance of controlling the loading rate of the subgrade filling.