Shear stress fluctuation and force chain structure in the granular flow

Abstract

The force chain structure formed in granular flow has a great effect on shear stress of the granular. In this paper, we studied on the fluctuation of shear stress and formation of the force chain structures in the granular with slow flow using concentric cylinder method. The experimental results show that the frequency and amplitude of the shear stress fluctuation change obviously at different shearing velocity and granular size, and the frequency distribution of the stress fluctuation has an inverse “S” shape. At the same time, the carbon paper depression approach was used to record the quantity and distribution of the stress points, which act on the cylinder wall due to the high pressure caused by the force chain structure. The results also verify that the shear velocity and the particle size influence the formation of the force chain at the critical formation conditions, leading to different distribution of the high pressure points.