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A two-dimensional analogue material formed of rod cylinders of chalk is tested under onedimensional oedometric loading conditions. Passive non-destructive Acoustic Emission (AE) monitoring technique is used to document the occurrence of crushing of individual particles. While the AE activity is recorded by a sensor placed on the sample boundaries, the AE signals are also corroborated with the observations based on video records of the exposed face of the 2D sample, as well as vertical loading and displacement measurements of the global sample. In the process, one-dimensional tests on individual cylindrical rods were also conducted and their AE crushing signatures compared with the AE data recorded at the 2D sample scale. While AE signal features can capture the particle crushing in the 2D granular systems, their occurrence shows high complexities driven by internal crushing particle mechanisms and geometrical position of particles with respect to the AE monitoring device. The frequency content of AE signals shows some evidence of the existence of an AE signature for a typical particle crushing mechanism, which may be a consequence of the dynamic properties of the whole system.

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Granular soils exhibit particle crushing under certain loading circumstances, and it significantly affects their mechanical behaviour. However, the estimation of the particle crushing is extremely challenging. Therefore, new a technic based on passive non-destructive Acoustic Emission (AE) monitoring is explored to infer the extent and evolution of soil's particle size distribution. However, in this paper only individual particles under uniaxial compression are studied and the results should inform the interpretation of the laboratory tests on small scale soil samples. Different material types from rigid to soft and brittle to ductile are used in order to probe the AE characteristics and deduce the AE signature attached to various particle crushing mechanisms. The particle size and material type are the main parameters considered, and clear variation of the AE signal characteristics are detected. These encouraging findings on the use of AE monitoring system offer the possibility to identify the micro crushing event of soil particle in the macro soils.