3D Imaging of particle motion during penetrometer testing

摘要: We present the results of direct observation material rearrangement due to penetration a solid rod (penetrometer) through granular medium. Two different techniques and their advantages are discussed in this paper. investigate motion within bulk around rod. Transparent, polydisperse, irregularly shaped silica particles immersed index matching fluid used for detailed imaging interior pile. Motion is observed by confocal microscopy from bottom boundary up 100 particle diameters height. Image analysis indicates that rearrangements spread furthest not directly under penetrometer but ring penetrometer. In addition, direction preformed stress chains influences rearrangements. Material compressed one side exhibits anisotropic testing. Laser sheet scanning allows individual with greater accuracy, works best spherical only.