Investigation of the grain breakage behaviour of 2D granular materials with disordered pore distribution

Granular materials have been widely used in the field of geotechnical engineering. Being one of the intrinsic properties of granular materials, the internal grain porosity greatly affects their mechanical properties, grain crushing in particular. In this article, the single porous grains with different degrees of disordered pore distribution were generated and fully investigated with discrete element method (DEM). The degree of disorder of pore distribution is characterized by parameter Iv. The DEM results demonstrate that both number of pore and the disorder of pore distribution have great effects on crushing strength. A more disordered pore distribution could lead to higher stress concentration and the heterogeneity of stress distribution, which results in a lower crushing strength. The shape of remaining fragments after grain crushing shows that the cracking path becomes more irregular with increasing disorder of pore distribution. For the three studied porosity, the crushing strength complies with an exponential-law diminution with the increase in disorder degree of pore distribution. The grain crushing strength was also statistically analysed by Weibull distribution. Similar to crushing strength, the Weibull modulus, m, of grain crushing strength follows an exponential law, in other words, m decreases with the disorder degree of porous texture. These results deepen our understanding of the effect of pore disorder over crushing behaviour of granular matter.