Quasi-Static and Dynamic Confined Compressive Behavior of Glass Beads by In-Situ X-Ray Micro-Computed Tomography

Abstract

Abstract Granular materials are one of the most important materials in several industries such as civil engineering, agriculture, and energy production. They are a collection of distinct macroscopic particles. Although these materials appear very simple to be described, they exhibit highly different mechanical behavior under quasi-static and dynamic loading conditions. Traditionally, glass beads have been considered as a benchmark granular material for the fundamental understanding of the mechanics of granular materials under complex mechanical loadings. In this study, we intend to characterize the compressive behavior of glass beads under confinement using in-situ X-ray micro-computed tomography at low (quasi-static) and high strain (dynamic) rates. At high strain rates, samples with similar bulk densities to the quasi-static samples are compressed using a long split Hopkinson pressure bar and later imaged with the tomography system to acquire their volumetric images. In the case of low strain rates, a similar sample is compressed, and subsequently, its volumetric images are captured at the same strain level as the dynamically compressed samples using the long split Hopkinson pressure bar. The volumetric images for each case are then analyzed to determine three-dimensional morphologies and to investigate and compare the damage and crushing characteristics of the glass beads at quasi-static and dynamic loading conditions.