Evolution of particle breakage process of coarse-grained soil under impact load

The particle breakage of coarse-grained soil occurs under impact load, and it may have a greater impact on its engineering characteristics. In order to investigate the particle breakage and evolutions of particle size distribution of coarse-grained soil under impact load, the impact test was carried out for two groups of typical graded coarse-grained soil by YX-30 electric heavy compaction, and the granulometric composition of moisture content, impact times and gradation were discussed. To further describe the intermediate process of particle breakage evolution, a new gradation equation was put forward in particle contents and relative particle size coordinate system, which could be used to describe continuous gradation of coarse-grained soil, and its adaptability was validated. A new particle breakage index was presented based on relative coordinate system, and then the mathematic expression was presented, the index was used to study the evolution law of particle breakage of coarse-grained soil under impact load. The results show that evolution of particle breakage process of coarse-grained soil under impact load can be described by the index presented in the paper. The particle breakage index increase and then decrease with the increase of moisture content, and the relation between the index and compaction work can be approximated by a hyperbola. © 2020, Central South University Press. All rights reserved.