Impact of Particle Shape on Crushing Behaviour of Rock Particles Using X-ray Micro-CT Testing and DEM Modelling

Particle crushing is a fundamental issue in the analysis of the deformation and failure behaviour of rockfill materials. The impact of morphology on the crushing behaviour of granite particles is investigated via a series of in-situ X-ray micro-CT tests and DEM simulations. Single-particle crushing tests are performed on rock particles of three different sizes. During mechanical loading, four in-situ CT scans are performed on each grain using an innovative loading apparatus. The CT test images reveal that the shape of the particle and its heterogeneous structure are crucial factors in determining failure patterns. Additionally, various shape indexes of rock particles change progressively and tend to stabilize, while their fragments follow a fractal distribution, seemingly independent of their initial size. Based on CT images, numerical particles with realistic shapes and internal flaws are generated using a proposed numerical method. It is observed that an increase in elongation index EI or flatness index FI results in a decrease in characteristic strength sigma 0\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\sigma _0$$\end{document} and an increase in Weibull modulus m. A novel loading apparatus has been developed for the realization of in-situ mu\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\mu$$\end{document}CT scans during single-particle crushing tests.CT test images reveal that particle shape and its heterogeneous structure are crucial factors in determining the failure pattern of rockfill particles.A new numerical method is proposed for generating particles, including both particle shape and microstructure.For particle shape, increasing the elongation index and flatness index of particle results in a decrease in characteristic strength sigma 0\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\sigma _0$$\end{document} and an increase in Weibull modulus .