Discrete element analysis of the effect of manual tamping operation on the mechanical properties of ballast bed

Abstract

At present, the theoretical analysis of manual tamping of ballast track has not been systematically carried out. The daily maintenance and repair is mainly based on experience. This paper uses the DEM-MBD co-simulation method to establish the ballast bed-sleeper-tamping machine model, simulates the manual tamping process under specific working conditions, and analyzes the influence of manual tamping on the movement trend, the compactness and the contact state of ballast. The results show that: a) The effect of filling the instantaneous “gap” at the bottom of the sleeper is mainly realized in the stage of inserting, b) The stage of withdrawing from the ballast bed will not cause secondary disturbance to the ballast bed area at the bottom of the sleeper, c) The compactness of the ballast bed in the shallow area at the bottom of the sleeper is improved after tamping, d) The bearing capacity of the ballast bed is guaranteed, e) The difference of contact state between ballast is significantly reduced after tamping and finally, f) The load transmission path inside the ballast bed can be improved after tamping.