Particle mechanics modeling of the effect of aggregate shape on creep of durable rockfills

The role of aggregate shapes in creep of durable rockfills is investigated using particle mechanics method. Both one-dimensional compressional creep and direct shear creep tests are performed on numerical rockfills consisting of rounded or irregular aggregates. Under one-dimensional compression, the creep displacements of irregular samples were greater than rounded samples. Under direct shear, the creep displacements of rounded samples could be the same magnitudes of or even larger than irregular samples. A concept of key aggregates is proposed to explain the evolution of force chains in rockfills. The different creep behavior of wet rounded and irregular aggregates is briefly discussed.