A Constitutive Model Allowing for Particle Size-Shape Coevolution

Abstract

This paper presents a constitutive model developed within the Continuum Breakage Mechanics (CBM) framework. The proposed model explicitly accounts for particle shape evolution during the compression of crushable granular materials. Most importantly, the proposed formulation includes a novel expression of the dissipation function that enables a versatile definition of the rate of particle shape evolution during crushing. It is shown that this approach overcomes the limitations of previous formulations by relaxing the constraints that restricted the viable range of the coevolution constants, thus allowing for better alignment with the shape evolution trends observed in crushable granular materials. Additionally, the framework extends its capability to simulate more general loading conditions beyond isotropic compression, thus broadening its practical applicability. The model is validated against synthetic data obtained with a level set discrete element model (LS-DEM) able to resolve complex particle shapes and their evolution. The results demonstrate the promising performance of the model in capturing the compression behavior of crushable granular materials.