Phase segregation and avalanches in multispecies sandpiles

A stochastic lattice model for the simulation of sandpiles is presented. The model allows for the numerical investigation of the phase segregation phenomenon occurring when different granular species are initially mixed together before deposition. The model includes the collective motion of grains along the pile surface and produces the so-called landslides. The parameters of the model are discussed. The distribution of avalanche sizes is found to broaden when the number of grain types increases. This result raises new questions about previously reported experimental observations of avalanche size distributions.