Quantum mechanics

Algorithm

Hardening (computing)

Engineering

Breakage

Metallurgy

Materials science

Layer (electronics)

Particle size

Computer science

Chemical engineering

Classical mechanics

Geology

Oceanography

Fractal

Physics

Contact force

Granular material

Mathematics

Particle-size distribution

Mathematical analysis

Comminution

Particle (ecology)

Composite material

Fragment (logic)

Structural engineering

Hydrostatic equilibrium

Discrete element method

Mechanics

Powder Technology

Granular breakage is a common phenomenon among rockfill dams, mineral engineering, and geological phenomenon. In this work, we perform one-dimensional compression tests using the discrete element method to study the influences of fragmentation patterns during comminution. Our results show that small fragments increase the coordination number of larger particles and create “hydrostatic” confinement. The combined effect of size hardening law of particle strength (i.e., smaller is stronger) and increasing hydrostatic confinement result in the stagnation of particle size reduction. When more and more small fragments participate in the force transmission, particle contact force evolves from exponential distribution to fractal distribution. With the increasing applied stress, breakage events become more spatially localized. Our findings indicate that particle breakage and size hardening law of particle strength would be reasons for the robust fractal structure in granular materials, i.e., both particle size and particle contact force are distributed in a fractal manner.

Discrete element modeling of particle breakage considering different fragment replacement modes