A Multiscale Investigation of the Effects of Water on Grain Crushing

The mechanical behavior of a granular medium is closely related to its saturation state. One of the underlying phenomena controlling this dependence is particle breakage. In the presence of water, the strength of a particle is weakened through various physical–chemical processes, which lead to an increase in the intensity of particle crushing. The acceleration of the particles fracturing results in the distinctive mechanical response usually observed in unsaturated soils. A multiscale experimental study was conducted to establish a causal relationship between the change of saturation and the increased breakage rate. Oedometric tests were used to understand the effects of saturation on the mechanics of the granular packing, while crushing and wedge splitting tests help appreciate the micromechanical origins of this typical behavior.