Influences of loading rate and preloading on the mechanical properties of dry elasto-plastic granules under compression

To ensure high quality of granular products post-industrial operations, it is necessary to precisely define their micro-macro mechanical properties. However, such an endeavor is arduous, owing to their highly inhomogeneous, anisotropic and history-dependent nature. In this article, we present the distributed granular micromechanical and macromechanical, energetic and breakage characteristics using statistical distributions. We describe the material behavior of elastoplastic zeolite 4AK granules under uniaxial compressive loading until primary breakage, and localized cyclic loading up to different maximum force levels, at different displacement-controlled loading rates. The observed force-displacement behavior had been approximated and further evaluated using well-known contact models. The results provide the basis for a detailed analysis of the viscous behavior of zeolite 4AK granules in the moist and wet states, indicating that higher compressive loads are required at higher displacement-controlled loading rates to realize equivalent deformation and breakage probability achieved by loads at lower displacement-controlled loading rates.