A new powder tester to investigate the anisotropic consolidation behaviour

The anisotropic behaviour is significant for many applications in the handling of bulk solids, for instance pelleting or silo design. A new powder tester has been developed to measure the unconfined yield strength in uniaxial direction, which means consolidation and collapse stresses in the same direction, as well as to measure the anisotropic unconfined yield strength in biaxial direction, which means consolidation and collapse stresses are in orthogonal directions. The ratio between the anisotropic and the uniaxial unconfined yield strength yields the intensity of the anisotropic consolidation behaviour. The development of the tester and the development of the measurement procedures as well as first experimental results are presented in this paper.