Abstract: The dynamic compaction method is widely used in high fill reinforcement, but there are few methods to determine the reinforcement range based on the theoretical calculation, furthermore, there are fewer methods to describe the transverse reinforcement width. However, the reinforcement depth and width are the key to the dynamic compaction design. On this basis, the method for calculating the internal settlement of dynamic compaction based on the random medium theory is established. The model only contains two parameters, i.e., the influence angle β and the compression coefficient η. The field tests on dynamic compaction of earth and stone in Chengde Airport shows that the model can be used to calculate the internal settlement of soils. The concept of the critical settlement is put forward, and the critical settlement of cohesionless earth rock materials is determined to be 0.04 m. Finally, the fast chart results of dynamic consolidation range based on the depth of ramming pit are given. The proposed method realizes the innovation and rapid application of dynamic consolidation theory and method, and provides direct reference results for the related projects.