Influence of Particle-Scale Properties on Fracture Behavior of Silica Sand

Abstract

The distribution of stresses within individual granular particles subjected to one-dimensional (1D) confined compression is affected by various particle-scale properties, such as morphology, kinematics, position, crystal structure, and the interaction of the particles (i.e., the local contact network). A thorough examination of the effects of particle-scale properties on the variation of stresses within individual particles and the fracture of particles in granular materials is essential for the theoretical analysis and modeling of the engineering behavior of granular materials. In this study, three-dimensional (3D) synchrotron microcomputed tomography (SMT) and 3D X-ray diffraction microscopy (3DXRD) that are nondestructive techniques will be concurrently used to quantify the variation of internal particle stresses, as well as the particle-scale properties of a specimen composed of Ottawa sand that will be subjected to a 1D confined compression. The effects of the particle properties on the variation of the particles internal stresses and the fracture of particles will be studied in detail. The importance of the particle-scale properties based on their effect on the variation of particle stress will be ranked using a feature selection algorithm called RReliefF. The significant particle properties (kinematics, contact number, the relative orientation of the local contact network for the loading direction, and position) by the feature selection algorithm will be investigated further to uncover their influence on the internal particle stresses. In addition, the effects of the particle-scale properties on the fracture of the particles will be examined. The fracture of the sand particles proved to be a complex phenomenon that was controlled by particle-scale properties and by the interaction between the particles. The relative orientation of the fracture surface in the fractured particles was examined to assess the effect particle shape and local contact network of the particles on the fracture of the particles.