Mechanical behavior of stored bulk deformable particles

The paper discusses the interest of conventional triaxial tests for a better understanding of both the mechanical behavior and flow properties of stored bulk particles. It proposes a rheological characterization of granular food-stuffs on diverse types of stress path. The characteristic state concept or disaggregation threshold of the particulate structure reveals to be quite suitable and even indispensable for examining the mechanical behavior and the flow ability of the stored bulk materials. The experimental results readily suggest, as an indicator of arching effect, a rheological index that characterizes the particle interlocking breakdown and the flow ability in silos. A double shear tester has been devised to examine dilatancy effects on wall friction measurement.