A vehicle-track-subgrade coupling dynamics vertical model was applied to study the probability distribution characteristics of dynamic influence coefficients φ_i of ballast track subgrade with vertical profile irregularity. According to the relationship between cumulative deformation state characteristics and loading levels revealed by model test of typical coarse-grained soil filler of subgrade under cyclic loading, it is found that the embankment below subgrade is in a time-independent deformation state, and subgrade filler is in weak-time effect state. Using the dynamic strength of subgrade structure, long-term dynamic stability and cyclic deformation as design control indicators, the technical conditions of the high-speed railway ballast track subgrade structure were analyzed. The study shows that:lg φ_i which characterize the degree of subgrade bearing the dynamic effect of the train along the line longitudinal direction, obeys the normal distribution; the cumulative deformation state of each structural layer of the subgrade under train load is closely related to the nature of the filler; the subgrade structure's long-term dynamic stability is the main design control factor. Accordingly the technical standards for 350km/h high-speed rail double-layer subgrade structure of ballast track was proposed.