Abstract: In order to provide a theoretical basis for the precise quantitative control of solid tamping effect of gangue and promote the maximum utilization of gangue filling technology, the mechanical response such as displacement, crushing and force chain evolution in the process of gangue particle compression and tamping is deeply investigated. The numerical simulation method based on discrete element was used to construct a gangue particle cluster model, and the parameter calibration and model verification were carried out in combination with water overflow test, friction physical test and steel drum compression test. Through simulation, the dynamic force chain evolution of gangue particle clusters under different compression rates (1.0, 0.9, 0.8, 0.7), and the effect of different particle shapes (prismatic, elongated, spherical), particle sizes (0.048, 0.054, 0.060, 0.065 m) and loading speeds (0.2, 0.5, 1.0 mm/s) on the stress-strain curves of gangue particle clusters were analyzed in detail, which reveals the bonding-breaking-contact transformation process and the breaking sequence of particle clusters. The research results showed that: with the progress of compression, the number of bonds between particles in the state of breaking and contacting gradually increased, and the number of bonds in the state of bonding gradually decreased, and the transformation process of bonding-breaking-contact and the breaking sequence of particle cluster tip to whole particle cluster were presented. The formation and extension of the force chain correspond to the breaking, displacement and inset of the block, and the lengthening and penetrating of the high stress force chain correspond to the breaking of the particle cluster, which will lead to the increase of the stress concentration. In the compression test of gangue under different conditions, the influence degree of particle shape, particle size and loading speed on the stress-strain curve ranges from large to small. Spherical particles break late because of their compact structure and large number of bonding bonds, while prismatic and elongated particles break early and disperse because of their many angles.