Particle Breakage Characteristics of Coarse-Grained Filler under Heavy-Haul Train Load

ABSTRACT This article presents a series of cyclic triaxial tests to investigate the particle breakage characteristics of coarse-grained filler under heavy-haul train load. The results show that the main patterns of particle breakage for large-sized particles (the particle size between 22.4 and 31.5 mm) are fracture and abrasion, and the particle breakage makes the outer contour of the particle closer to the sphere. The particle breakage is found in the process of vibratory compaction of specimens, and the particle breakage caused by isotropic consolidation under low confining pressure (no more than 300 kPa) can be ignored. It is also found that significant particle breakage occurs during cyclic loading, characterized by the reduction of the large-sized particles (the particle size between 16 and 31.5 mm) and the increase of fines content. In addition, further particle breakage is caused by the increase in the cyclic stress ratio. Based on the test results, a power function equation of Marsal’s breakage factors and cyclic stress ratio is proposed.